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authorLinus Torvalds <torvalds@linux-foundation.org>2009-06-24 10:26:54 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2009-06-24 10:26:54 -0700
commitc3cb5e193937c7aa50c323e7933507020bd26340 (patch)
treeea36213ccd29dc4caf2f729fd51b2d489b591a31
parentea94b5034bbebc964115f119d6cd330757fce7f9 (diff)
parentf40c67f0f7e2767f80f7cbcbc1ab86c4113c202e (diff)
Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm
* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm: (48 commits) dm mpath: change to be request based dm: disable interrupt when taking map_lock dm: do not set QUEUE_ORDERED_DRAIN if request based dm: enable request based option dm: prepare for request based option dm raid1: add userspace log dm: calculate queue limits during resume not load dm log: fix create_log_context to use logical_block_size of log device dm target:s introduce iterate devices fn dm table: establish queue limits by copying table limits dm table: replace struct io_restrictions with struct queue_limits dm table: validate device logical_block_size dm table: ensure targets are aligned to logical_block_size dm ioctl: support cookies for udev dm: sysfs add suspended attribute dm table: improve warning message when devices not freed before destruction dm mpath: add service time load balancer dm mpath: add queue length load balancer dm mpath: add start_io and nr_bytes to path selectors dm snapshot: use barrier when writing exception store ...
-rw-r--r--Documentation/device-mapper/dm-log.txt54
-rw-r--r--Documentation/device-mapper/dm-queue-length.txt39
-rw-r--r--Documentation/device-mapper/dm-service-time.txt91
-rw-r--r--drivers/md/Kconfig30
-rw-r--r--drivers/md/Makefile5
-rw-r--r--drivers/md/dm-crypt.c19
-rw-r--r--drivers/md/dm-delay.c26
-rw-r--r--drivers/md/dm-exception-store.c2
-rw-r--r--drivers/md/dm-exception-store.h2
-rw-r--r--drivers/md/dm-io.c14
-rw-r--r--drivers/md/dm-ioctl.c27
-rw-r--r--drivers/md/dm-linear.c15
-rw-r--r--drivers/md/dm-log-userspace-base.c696
-rw-r--r--drivers/md/dm-log-userspace-transfer.c276
-rw-r--r--drivers/md/dm-log-userspace-transfer.h18
-rw-r--r--drivers/md/dm-log.c9
-rw-r--r--drivers/md/dm-mpath.c334
-rw-r--r--drivers/md/dm-path-selector.h8
-rw-r--r--drivers/md/dm-queue-length.c263
-rw-r--r--drivers/md/dm-raid1.c17
-rw-r--r--drivers/md/dm-region-hash.c2
-rw-r--r--drivers/md/dm-round-robin.c2
-rw-r--r--drivers/md/dm-service-time.c339
-rw-r--r--drivers/md/dm-snap-persistent.c2
-rw-r--r--drivers/md/dm-snap.c11
-rw-r--r--drivers/md/dm-stripe.c33
-rw-r--r--drivers/md/dm-sysfs.c9
-rw-r--r--drivers/md/dm-table.c465
-rw-r--r--drivers/md/dm.c1133
-rw-r--r--drivers/md/dm.h35
-rw-r--r--include/linux/Kbuild1
-rw-r--r--include/linux/connector.h4
-rw-r--r--include/linux/device-mapper.h47
-rw-r--r--include/linux/dm-ioctl.h14
-rw-r--r--include/linux/dm-log-userspace.h386
35 files changed, 3993 insertions, 435 deletions
diff --git a/Documentation/device-mapper/dm-log.txt b/Documentation/device-mapper/dm-log.txt
new file mode 100644
index 000000000000..994dd75475a6
--- /dev/null
+++ b/Documentation/device-mapper/dm-log.txt
@@ -0,0 +1,54 @@
+Device-Mapper Logging
+=====================
+The device-mapper logging code is used by some of the device-mapper
+RAID targets to track regions of the disk that are not consistent.
+A region (or portion of the address space) of the disk may be
+inconsistent because a RAID stripe is currently being operated on or
+a machine died while the region was being altered. In the case of
+mirrors, a region would be considered dirty/inconsistent while you
+are writing to it because the writes need to be replicated for all
+the legs of the mirror and may not reach the legs at the same time.
+Once all writes are complete, the region is considered clean again.
+
+There is a generic logging interface that the device-mapper RAID
+implementations use to perform logging operations (see
+dm_dirty_log_type in include/linux/dm-dirty-log.h). Various different
+logging implementations are available and provide different
+capabilities. The list includes:
+
+Type Files
+==== =====
+disk drivers/md/dm-log.c
+core drivers/md/dm-log.c
+userspace drivers/md/dm-log-userspace* include/linux/dm-log-userspace.h
+
+The "disk" log type
+-------------------
+This log implementation commits the log state to disk. This way, the
+logging state survives reboots/crashes.
+
+The "core" log type
+-------------------
+This log implementation keeps the log state in memory. The log state
+will not survive a reboot or crash, but there may be a small boost in
+performance. This method can also be used if no storage device is
+available for storing log state.
+
+The "userspace" log type
+------------------------
+This log type simply provides a way to export the log API to userspace,
+so log implementations can be done there. This is done by forwarding most
+logging requests to userspace, where a daemon receives and processes the
+request.
+
+The structure used for communication between kernel and userspace are
+located in include/linux/dm-log-userspace.h. Due to the frequency,
+diversity, and 2-way communication nature of the exchanges between
+kernel and userspace, 'connector' is used as the interface for
+communication.
+
+There are currently two userspace log implementations that leverage this
+framework - "clustered_disk" and "clustered_core". These implementations
+provide a cluster-coherent log for shared-storage. Device-mapper mirroring
+can be used in a shared-storage environment when the cluster log implementations
+are employed.
diff --git a/Documentation/device-mapper/dm-queue-length.txt b/Documentation/device-mapper/dm-queue-length.txt
new file mode 100644
index 000000000000..f4db2562175c
--- /dev/null
+++ b/Documentation/device-mapper/dm-queue-length.txt
@@ -0,0 +1,39 @@
+dm-queue-length
+===============
+
+dm-queue-length is a path selector module for device-mapper targets,
+which selects a path with the least number of in-flight I/Os.
+The path selector name is 'queue-length'.
+
+Table parameters for each path: [<repeat_count>]
+ <repeat_count>: The number of I/Os to dispatch using the selected
+ path before switching to the next path.
+ If not given, internal default is used. To check
+ the default value, see the activated table.
+
+Status for each path: <status> <fail-count> <in-flight>
+ <status>: 'A' if the path is active, 'F' if the path is failed.
+ <fail-count>: The number of path failures.
+ <in-flight>: The number of in-flight I/Os on the path.
+
+
+Algorithm
+=========
+
+dm-queue-length increments/decrements 'in-flight' when an I/O is
+dispatched/completed respectively.
+dm-queue-length selects a path with the minimum 'in-flight'.
+
+
+Examples
+========
+In case that 2 paths (sda and sdb) are used with repeat_count == 128.
+
+# echo "0 10 multipath 0 0 1 1 queue-length 0 2 1 8:0 128 8:16 128" \
+ dmsetup create test
+#
+# dmsetup table
+test: 0 10 multipath 0 0 1 1 queue-length 0 2 1 8:0 128 8:16 128
+#
+# dmsetup status
+test: 0 10 multipath 2 0 0 0 1 1 E 0 2 1 8:0 A 0 0 8:16 A 0 0
diff --git a/Documentation/device-mapper/dm-service-time.txt b/Documentation/device-mapper/dm-service-time.txt
new file mode 100644
index 000000000000..7d00668e97bb
--- /dev/null
+++ b/Documentation/device-mapper/dm-service-time.txt
@@ -0,0 +1,91 @@
+dm-service-time
+===============
+
+dm-service-time is a path selector module for device-mapper targets,
+which selects a path with the shortest estimated service time for
+the incoming I/O.
+
+The service time for each path is estimated by dividing the total size
+of in-flight I/Os on a path with the performance value of the path.
+The performance value is a relative throughput value among all paths
+in a path-group, and it can be specified as a table argument.
+
+The path selector name is 'service-time'.
+
+Table parameters for each path: [<repeat_count> [<relative_throughput>]]
+ <repeat_count>: The number of I/Os to dispatch using the selected
+ path before switching to the next path.
+ If not given, internal default is used. To check
+ the default value, see the activated table.
+ <relative_throughput>: The relative throughput value of the path
+ among all paths in the path-group.
+ The valid range is 0-100.
+ If not given, minimum value '1' is used.
+ If '0' is given, the path isn't selected while
+ other paths having a positive value are available.
+
+Status for each path: <status> <fail-count> <in-flight-size> \
+ <relative_throughput>
+ <status>: 'A' if the path is active, 'F' if the path is failed.
+ <fail-count>: The number of path failures.
+ <in-flight-size>: The size of in-flight I/Os on the path.
+ <relative_throughput>: The relative throughput value of the path
+ among all paths in the path-group.
+
+
+Algorithm
+=========
+
+dm-service-time adds the I/O size to 'in-flight-size' when the I/O is
+dispatched and substracts when completed.
+Basically, dm-service-time selects a path having minimum service time
+which is calculated by:
+
+ ('in-flight-size' + 'size-of-incoming-io') / 'relative_throughput'
+
+However, some optimizations below are used to reduce the calculation
+as much as possible.
+
+ 1. If the paths have the same 'relative_throughput', skip
+ the division and just compare the 'in-flight-size'.
+
+ 2. If the paths have the same 'in-flight-size', skip the division
+ and just compare the 'relative_throughput'.
+
+ 3. If some paths have non-zero 'relative_throughput' and others
+ have zero 'relative_throughput', ignore those paths with zero
+ 'relative_throughput'.
+
+If such optimizations can't be applied, calculate service time, and
+compare service time.
+If calculated service time is equal, the path having maximum
+'relative_throughput' may be better. So compare 'relative_throughput'
+then.
+
+
+Examples
+========
+In case that 2 paths (sda and sdb) are used with repeat_count == 128
+and sda has an average throughput 1GB/s and sdb has 4GB/s,
+'relative_throughput' value may be '1' for sda and '4' for sdb.
+
+# echo "0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 1 8:16 128 4" \
+ dmsetup create test
+#
+# dmsetup table
+test: 0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 1 8:16 128 4
+#
+# dmsetup status
+test: 0 10 multipath 2 0 0 0 1 1 E 0 2 2 8:0 A 0 0 1 8:16 A 0 0 4
+
+
+Or '2' for sda and '8' for sdb would be also true.
+
+# echo "0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 2 8:16 128 8" \
+ dmsetup create test
+#
+# dmsetup table
+test: 0 10 multipath 0 0 1 1 service-time 0 2 2 8:0 128 2 8:16 128 8
+#
+# dmsetup status
+test: 0 10 multipath 2 0 0 0 1 1 E 0 2 2 8:0 A 0 0 2 8:16 A 0 0 8
diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig
index 36e0675be9f7..020f9573fd82 100644
--- a/drivers/md/Kconfig
+++ b/drivers/md/Kconfig
@@ -231,6 +231,17 @@ config DM_MIRROR
Allow volume managers to mirror logical volumes, also
needed for live data migration tools such as 'pvmove'.
+config DM_LOG_USERSPACE
+ tristate "Mirror userspace logging (EXPERIMENTAL)"
+ depends on DM_MIRROR && EXPERIMENTAL && NET
+ select CONNECTOR
+ ---help---
+ The userspace logging module provides a mechanism for
+ relaying the dm-dirty-log API to userspace. Log designs
+ which are more suited to userspace implementation (e.g.
+ shared storage logs) or experimental logs can be implemented
+ by leveraging this framework.
+
config DM_ZERO
tristate "Zero target"
depends on BLK_DEV_DM
@@ -249,6 +260,25 @@ config DM_MULTIPATH
---help---
Allow volume managers to support multipath hardware.
+config DM_MULTIPATH_QL
+ tristate "I/O Path Selector based on the number of in-flight I/Os"
+ depends on DM_MULTIPATH
+ ---help---
+ This path selector is a dynamic load balancer which selects
+ the path with the least number of in-flight I/Os.
+
+ If unsure, say N.
+
+config DM_MULTIPATH_ST
+ tristate "I/O Path Selector based on the service time"
+ depends on DM_MULTIPATH
+ ---help---
+ This path selector is a dynamic load balancer which selects
+ the path expected to complete the incoming I/O in the shortest
+ time.
+
+ If unsure, say N.
+
config DM_DELAY
tristate "I/O delaying target (EXPERIMENTAL)"
depends on BLK_DEV_DM && EXPERIMENTAL
diff --git a/drivers/md/Makefile b/drivers/md/Makefile
index 45cc5951d928..1dc4185bd781 100644
--- a/drivers/md/Makefile
+++ b/drivers/md/Makefile
@@ -8,6 +8,8 @@ dm-multipath-y += dm-path-selector.o dm-mpath.o
dm-snapshot-y += dm-snap.o dm-exception-store.o dm-snap-transient.o \
dm-snap-persistent.o
dm-mirror-y += dm-raid1.o
+dm-log-userspace-y \
+ += dm-log-userspace-base.o dm-log-userspace-transfer.o
md-mod-y += md.o bitmap.o
raid456-y += raid5.o
raid6_pq-y += raid6algos.o raid6recov.o raid6tables.o \
@@ -36,8 +38,11 @@ obj-$(CONFIG_BLK_DEV_DM) += dm-mod.o
obj-$(CONFIG_DM_CRYPT) += dm-crypt.o
obj-$(CONFIG_DM_DELAY) += dm-delay.o
obj-$(CONFIG_DM_MULTIPATH) += dm-multipath.o dm-round-robin.o
+obj-$(CONFIG_DM_MULTIPATH_QL) += dm-queue-length.o
+obj-$(CONFIG_DM_MULTIPATH_ST) += dm-service-time.o
obj-$(CONFIG_DM_SNAPSHOT) += dm-snapshot.o
obj-$(CONFIG_DM_MIRROR) += dm-mirror.o dm-log.o dm-region-hash.o
+obj-$(CONFIG_DM_LOG_USERSPACE) += dm-log-userspace.o
obj-$(CONFIG_DM_ZERO) += dm-zero.o
quiet_cmd_unroll = UNROLL $@
diff --git a/drivers/md/dm-crypt.c b/drivers/md/dm-crypt.c
index 53394e863c74..9933eb861c71 100644
--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -1132,6 +1132,7 @@ static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
goto bad_crypt_queue;
}
+ ti->num_flush_requests = 1;
ti->private = cc;
return 0;
@@ -1189,6 +1190,13 @@ static int crypt_map(struct dm_target *ti, struct bio *bio,
union map_info *map_context)
{
struct dm_crypt_io *io;
+ struct crypt_config *cc;
+
+ if (unlikely(bio_empty_barrier(bio))) {
+ cc = ti->private;
+ bio->bi_bdev = cc->dev->bdev;
+ return DM_MAPIO_REMAPPED;
+ }
io = crypt_io_alloc(ti, bio, bio->bi_sector - ti->begin);
@@ -1305,9 +1313,17 @@ static int crypt_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
}
+static int crypt_iterate_devices(struct dm_target *ti,
+ iterate_devices_callout_fn fn, void *data)
+{
+ struct crypt_config *cc = ti->private;
+
+ return fn(ti, cc->dev, cc->start, data);
+}
+
static struct target_type crypt_target = {
.name = "crypt",
- .version= {1, 6, 0},
+ .version = {1, 7, 0},
.module = THIS_MODULE,
.ctr = crypt_ctr,
.dtr = crypt_dtr,
@@ -1318,6 +1334,7 @@ static struct target_type crypt_target = {
.resume = crypt_resume,
.message = crypt_message,
.merge = crypt_merge,
+ .iterate_devices = crypt_iterate_devices,
};
static int __init dm_crypt_init(void)
diff --git a/drivers/md/dm-delay.c b/drivers/md/dm-delay.c
index 559dbb52bc85..4e5b843cd4d7 100644
--- a/drivers/md/dm-delay.c
+++ b/drivers/md/dm-delay.c
@@ -197,6 +197,7 @@ out:
mutex_init(&dc->timer_lock);
atomic_set(&dc->may_delay, 1);
+ ti->num_flush_requests = 1;
ti->private = dc;
return 0;
@@ -278,8 +279,9 @@ static int delay_map(struct dm_target *ti, struct bio *bio,
if ((bio_data_dir(bio) == WRITE) && (dc->dev_write)) {
bio->bi_bdev = dc->dev_write->bdev;
- bio->bi_sector = dc->start_write +
- (bio->bi_sector - ti->begin);
+ if (bio_sectors(bio))
+ bio->bi_sector = dc->start_write +
+ (bio->bi_sector - ti->begin);
return delay_bio(dc, dc->write_delay, bio);
}
@@ -316,9 +318,26 @@ static int delay_status(struct dm_target *ti, status_type_t type,
return 0;
}
+static int delay_iterate_devices(struct dm_target *ti,
+ iterate_devices_callout_fn fn, void *data)
+{
+ struct delay_c *dc = ti->private;
+ int ret = 0;
+
+ ret = fn(ti, dc->dev_read, dc->start_read, data);
+ if (ret)
+ goto out;
+
+ if (dc->dev_write)
+ ret = fn(ti, dc->dev_write, dc->start_write, data);
+
+out:
+ return ret;
+}
+
static struct target_type delay_target = {
.name = "delay",
- .version = {1, 0, 2},
+ .version = {1, 1, 0},
.module = THIS_MODULE,
.ctr = delay_ctr,
.dtr = delay_dtr,
@@ -326,6 +345,7 @@ static struct target_type delay_target = {
.presuspend = delay_presuspend,
.resume = delay_resume,
.status = delay_status,
+ .iterate_devices = delay_iterate_devices,
};
static int __init dm_delay_init(void)
diff --git a/drivers/md/dm-exception-store.c b/drivers/md/dm-exception-store.c
index 75d8081a9041..c3ae51584b12 100644
--- a/drivers/md/dm-exception-store.c
+++ b/drivers/md/dm-exception-store.c
@@ -216,7 +216,7 @@ int dm_exception_store_create(struct dm_target *ti, int argc, char **argv,
return -EINVAL;
}
- type = get_type(argv[1]);
+ type = get_type(&persistent);
if (!type) {
ti->error = "Exception store type not recognised";
r = -EINVAL;
diff --git a/drivers/md/dm-exception-store.h b/drivers/md/dm-exception-store.h
index c92701dc5001..2442c8c07898 100644
--- a/drivers/md/dm-exception-store.h
+++ b/drivers/md/dm-exception-store.h
@@ -156,7 +156,7 @@ static inline void dm_consecutive_chunk_count_inc(struct dm_snap_exception *e)
*/
static inline sector_t get_dev_size(struct block_device *bdev)
{
- return bdev->bd_inode->i_size >> SECTOR_SHIFT;
+ return i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
}
static inline chunk_t sector_to_chunk(struct dm_exception_store *store,
diff --git a/drivers/md/dm-io.c b/drivers/md/dm-io.c
index e73aabd61cd7..3a2e6a2f8bdd 100644
--- a/drivers/md/dm-io.c
+++ b/drivers/md/dm-io.c
@@ -22,6 +22,7 @@ struct dm_io_client {
/* FIXME: can we shrink this ? */
struct io {
unsigned long error_bits;
+ unsigned long eopnotsupp_bits;
atomic_t count;
struct task_struct *sleeper;
struct dm_io_client *client;
@@ -107,8 +108,11 @@ static inline unsigned bio_get_region(struct bio *bio)
*---------------------------------------------------------------*/
static void dec_count(struct io *io, unsigned int region, int error)
{
- if (error)
+ if (error) {
set_bit(region, &io->error_bits);
+ if (error == -EOPNOTSUPP)
+ set_bit(region, &io->eopnotsupp_bits);
+ }
if (atomic_dec_and_test(&io->count)) {
if (io->sleeper)
@@ -360,7 +364,9 @@ static int sync_io(struct dm_io_client *client, unsigned int num_regions,
return -EIO;
}
+retry:
io.error_bits = 0;
+ io.eopnotsupp_bits = 0;
atomic_set(&io.count, 1); /* see dispatch_io() */
io.sleeper = current;
io.client = client;
@@ -377,6 +383,11 @@ static int sync_io(struct dm_io_client *client, unsigned int num_regions,
}
set_current_state(TASK_RUNNING);
+ if (io.eopnotsupp_bits && (rw & (1 << BIO_RW_BARRIER))) {
+ rw &= ~(1 << BIO_RW_BARRIER);
+ goto retry;
+ }
+
if (error_bits)
*error_bits = io.error_bits;
@@ -397,6 +408,7 @@ static int async_io(struct dm_io_client *client, unsigned int num_regions,
io = mempool_alloc(client->pool, GFP_NOIO);
io->error_bits = 0;
+ io->eopnotsupp_bits = 0;
atomic_set(&io->count, 1); /* see dispatch_io() */
io->sleeper = NULL;
io->client = client;
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c
index 1128d3fba797..7f77f18fcafa 100644
--- a/drivers/md/dm-ioctl.c
+++ b/drivers/md/dm-ioctl.c
@@ -276,7 +276,7 @@ retry:
up_write(&_hash_lock);
}
-static int dm_hash_rename(const char *old, const char *new)
+static int dm_hash_rename(uint32_t cookie, const char *old, const char *new)
{
char *new_name, *old_name;
struct hash_cell *hc;
@@ -333,7 +333,7 @@ static int dm_hash_rename(const char *old, const char *new)
dm_table_put(table);
}
- dm_kobject_uevent(hc->md);
+ dm_kobject_uevent(hc->md, KOBJ_CHANGE, cookie);
dm_put(hc->md);
up_write(&_hash_lock);
@@ -680,6 +680,9 @@ static int dev_remove(struct dm_ioctl *param, size_t param_size)
__hash_remove(hc);
up_write(&_hash_lock);
+
+ dm_kobject_uevent(md, KOBJ_REMOVE, param->event_nr);
+
dm_put(md);
param->data_size = 0;
return 0;
@@ -715,7 +718,7 @@ static int dev_rename(struct dm_ioctl *param, size_t param_size)
return r;
param->data_size = 0;
- return dm_hash_rename(param->name, new_name);
+ return dm_hash_rename(param->event_nr, param->name, new_name);
}
static int dev_set_geometry(struct dm_ioctl *param, size_t param_size)
@@ -842,8 +845,11 @@ static int do_resume(struct dm_ioctl *param)
if (dm_suspended(md))
r = dm_resume(md);
- if (!r)
+
+ if (!r) {
+ dm_kobject_uevent(md, KOBJ_CHANGE, param->event_nr);
r = __dev_status(md, param);
+ }
dm_put(md);
return r;
@@ -1044,6 +1050,12 @@ static int populate_table(struct dm_table *table,
next = spec->next;
}
+ r = dm_table_set_type(table);
+ if (r) {
+ DMWARN("unable to set table type");
+ return r;
+ }
+
return dm_table_complete(table);
}
@@ -1089,6 +1101,13 @@ static int table_load(struct dm_ioctl *param, size_t param_size)
goto out;
}
+ r = dm_table_alloc_md_mempools(t);
+ if (r) {
+ DMWARN("unable to allocate mempools for this table");
+ dm_table_destroy(t);
+ goto out;
+ }
+
down_write(&_hash_lock);
hc = dm_get_mdptr(md);
if (!hc || hc->md != md) {
diff --git a/drivers/md/dm-linear.c b/drivers/md/dm-linear.c
index 79fb53e51c70..9184b6deb868 100644
--- a/drivers/md/dm-linear.c
+++ b/drivers/md/dm-linear.c
@@ -53,6 +53,7 @@ static int linear_ctr(struct dm_target *ti, unsigned int argc, char **argv)
goto bad;
}
+ ti->num_flush_requests = 1;
ti->private = lc;
return 0;
@@ -81,7 +82,8 @@ static void linear_map_bio(struct dm_target *ti, struct bio *bio)
struct linear_c *lc = ti->private;
bio->bi_bdev = lc->dev->bdev;
- bio->bi_sector = linear_map_sector(ti, bio->bi_sector);
+ if (bio_sectors(bio))
+ bio->bi_sector = linear_map_sector(ti, bio->bi_sector);
}
static int linear_map(struct dm_target *ti, struct bio *bio,
@@ -132,9 +134,17 @@ static int linear_merge(struct dm_target *ti, struct bvec_merge_data *bvm,
return min(max_size, q->merge_bvec_fn(q, bvm, biovec));
}
+static int linear_iterate_devices(struct dm_target *ti,
+ iterate_devices_callout_fn fn, void *data)
+{
+ struct linear_c *lc = ti->private;
+
+ return fn(ti, lc->dev, lc->start, data);
+}
+
static struct target_type linear_target = {
.name = "linear",
- .version= {1, 0, 3},
+ .version = {1, 1, 0},
.module = THIS_MODULE,
.ctr = linear_ctr,
.dtr = linear_dtr,
@@ -142,6 +152,7 @@ static struct target_type linear_target = {
.status = linear_status,
.ioctl = linear_ioctl,
.merge = linear_merge,
+ .iterate_devices = linear_iterate_devices,
};
int __init dm_linear_init(void)
diff --git a/drivers/md/dm-log-userspace-base.c b/drivers/md/dm-log-userspace-base.c
new file mode 100644
index 000000000000..e69b96560997
--- /dev/null
+++ b/drivers/md/dm-log-userspace-base.c
@@ -0,0 +1,696 @@
+/*
+ * Copyright (C) 2006-2009 Red Hat, Inc.
+ *
+ * This file is released under the LGPL.
+ */
+
+#include <linux/bio.h>
+#include <linux/dm-dirty-log.h>
+#include <linux/device-mapper.h>
+#include <linux/dm-log-userspace.h>
+
+#include "dm-log-userspace-transfer.h"
+
+struct flush_entry {
+ int type;
+ region_t region;
+ struct list_head list;
+};
+
+struct log_c {
+ struct dm_target *ti;
+ uint32_t region_size;
+ region_t region_count;
+ char uuid[DM_UUID_LEN];
+
+ char *usr_argv_str;
+ uint32_t usr_argc;
+
+ /*
+ * in_sync_hint gets set when doing is_remote_recovering. It
+ * represents the first region that needs recovery. IOW, the
+ * first zero bit of sync_bits. This can be useful for to limit
+ * traffic for calls like is_remote_recovering and get_resync_work,
+ * but be take care in its use for anything else.
+ */
+ uint64_t in_sync_hint;
+
+ spinlock_t flush_lock;
+ struct list_head flush_list; /* only for clear and mark requests */
+};
+
+static mempool_t *flush_entry_pool;
+
+static void *flush_entry_alloc(gfp_t gfp_mask, void *pool_data)
+{
+ return kmalloc(sizeof(struct flush_entry), gfp_mask);
+}
+
+static void flush_entry_free(void *element, void *pool_data)
+{
+ kfree(element);
+}
+
+static int userspace_do_request(struct log_c *lc, const char *uuid,
+ int request_type, char *data, size_t data_size,
+ char *rdata, size_t *rdata_size)
+{
+ int r;
+
+ /*
+ * If the server isn't there, -ESRCH is returned,
+ * and we must keep trying until the server is
+ * restored.
+ */
+retry:
+ r = dm_consult_userspace(uuid, request_type, data,
+ data_size, rdata, rdata_size);
+
+ if (r != -ESRCH)
+ return r;
+
+ DMERR(" Userspace log server not found.");
+ while (1) {
+ set_current_state(TASK_INTERRUPTIBLE);
+ schedule_timeout(2*HZ);
+ DMWARN("Attempting to contact userspace log server...");
+ r = dm_consult_userspace(uuid, DM_ULOG_CTR, lc->usr_argv_str,
+ strlen(lc->usr_argv_str) + 1,
+ NULL, NULL);
+ if (!r)
+ break;
+ }
+ DMINFO("Reconnected to userspace log server... DM_ULOG_CTR complete");
+ r = dm_consult_userspace(uuid, DM_ULOG_RESUME, NULL,
+ 0, NULL, NULL);
+ if (!r)
+ goto retry;
+
+ DMERR("Error trying to resume userspace log: %d", r);
+
+ return -ESRCH;
+}
+
+static int build_constructor_string(struct dm_target *ti,
+ unsigned argc, char **argv,
+ char **ctr_str)
+{
+ int i, str_size;
+ char *str = NULL;
+
+ *ctr_str = NULL;
+
+ for (i = 0, str_size = 0; i < argc; i++)
+ str_size += strlen(argv[i]) + 1; /* +1 for space between args */
+
+ str_size += 20; /* Max number of chars in a printed u64 number */
+
+ str = kzalloc(str_size, GFP_KERNEL);
+ if (!str) {
+ DMWARN("Unable to allocate memory for constructor string");
+ return -ENOMEM;
+ }
+
+ for (i = 0, str_size = 0; i < argc; i++)
+ str_size += sprintf(str + str_size, "%s ", argv[i]);
+ str_size += sprintf(str + str_size, "%llu",
+ (unsigned long long)ti->len);
+
+ *ctr_str = str;
+ return str_size;
+}
+
+/*
+ * userspace_ctr
+ *
+ * argv contains:
+ * <UUID> <other args>
+ * Where 'other args' is the userspace implementation specific log
+ * arguments. An example might be:
+ * <UUID> clustered_disk <arg count> <log dev> <region_size> [[no]sync]
+ *
+ * So, this module will strip off the <UUID> for identification purposes
+ * when communicating with userspace about a log; but will pass on everything
+ * else.
+ */
+static int userspace_ctr(struct dm_dirty_log *log, struct dm_target *ti,
+ unsigned argc, char **argv)
+{
+ int r = 0;
+ int str_size;
+ char *ctr_str = NULL;
+ struct log_c *lc = NULL;
+ uint64_t rdata;
+ size_t rdata_size = sizeof(rdata);
+
+ if (argc < 3) {
+ DMWARN("Too few arguments to userspace dirty log");
+ return -EINVAL;
+ }
+
+ lc = kmalloc(sizeof(*lc), GFP_KERNEL);
+ if (!lc) {
+ DMWARN("Unable to allocate userspace log context.");
+ return -ENOMEM;
+ }
+
+ lc->ti = ti;
+
+ if (strlen(argv[0]) > (DM_UUID_LEN - 1)) {
+ DMWARN("UUID argument too long.");
+ kfree(lc);
+ return -EINVAL;
+ }
+
+ strncpy(lc->uuid, argv[0], DM_UUID_LEN);
+ spin_lock_init(&lc->flush_lock);
+ INIT_LIST_HEAD(&lc->flush_list);
+
+ str_size = build_constructor_string(ti, argc - 1, argv + 1, &ctr_str);
+ if (str_size < 0) {
+ kfree(lc);
+ return str_size;
+ }
+
+ /* Send table string */
+ r = dm_consult_userspace(lc->uuid, DM_ULOG_CTR,
+ ctr_str, str_size, NULL, NULL);
+
+ if (r == -ESRCH) {
+ DMERR("Userspace log server not found");
+ goto out;
+ }
+
+ /* Since the region size does not change, get it now */
+ rdata_size = sizeof(rdata);
+ r = dm_consult_userspace(lc->uuid, DM_ULOG_GET_REGION_SIZE,
+ NULL, 0, (char *)&rdata, &rdata_size);
+
+ if (r) {
+ DMERR("Failed to get region size of dirty log");
+ goto out;
+ }
+
+ lc->region_size = (uint32_t)rdata;
+ lc->region_count = dm_sector_div_up(ti->len, lc->region_size);
+
+out:
+ if (r) {
+ kfree(lc);
+ kfree(ctr_str);
+ } else {
+ lc->usr_argv_str = ctr_str;
+ lc->usr_argc = argc;
+ log->context = lc;
+ }
+
+ return r;
+}
+
+static void userspace_dtr(struct dm_dirty_log *log)
+{
+ int r;
+ struct log_c *lc = log->context;
+
+ r = dm_consult_userspace(lc->uuid, DM_ULOG_DTR,
+ NULL, 0,
+ NULL, NULL);
+
+ kfree(lc->usr_argv_str);
+ kfree(lc);
+
+ return;
+}
+
+static int userspace_presuspend(struct dm_dirty_log *log)
+{
+ int r;
+ struct log_c *lc = log->context;
+
+ r = dm_consult_userspace(lc->uuid, DM_ULOG_PRESUSPEND,
+ NULL, 0,
+ NULL, NULL);
+
+ return r;
+}
+
+static int userspace_postsuspend(struct dm_dirty_log *log)
+{
+ int r;
+ struct log_c *lc = log->context;
+
+ r = dm_consult_userspace(lc->uuid, DM_ULOG_POSTSUSPEND,
+ NULL, 0,
+ NULL, NULL);
+
+ return r;
+}
+
+static int userspace_resume(struct dm_dirty_log *log)
+{
+ int r;
+ struct log_c *lc = log->context;
+
+ lc->in_sync_hint = 0;
+ r = dm_consult_userspace(lc->uuid, DM_ULOG_RESUME,
+ NULL, 0,
+ NULL, NULL);
+
+ return r;
+}
+
+static uint32_t userspace_get_region_size(struct dm_dirty_log *log)
+{
+ struct log_c *lc = log->context;
+
+ return lc->region_size;
+}
+
+/*
+ * userspace_is_clean
+ *
+ * Check whether a region is clean. If there is any sort of
+ * failure when consulting the server, we return not clean.
+ *
+ * Returns: 1 if clean, 0 otherwise
+ */
+static int userspace_is_clean(struct dm_dirty_log *log, region_t region)
+{
+ int r;
+ uint64_t region64 = (uint64_t)region;
+ int64_t is_clean;
+ size_t rdata_size;
+ struct log_c *lc = log->context;
+
+ rdata_size = sizeof(is_clean);
+ r = userspace_do_request(lc, lc->uuid, DM_ULOG_IS_CLEAN,
+ (char *)&region64, sizeof(region64),
+ (char *)&is_clean, &rdata_size);
+
+ return (r) ? 0 : (int)is_clean;
+}
+
+/*
+ * userspace_in_sync
+ *
+ * Check if the region is in-sync. If there is any sort
+ * of failure when consulting the server, we assume that
+ * the region is not in sync.
+ *
+ * If 'can_block' is set, return immediately
+ *
+ * Returns: 1 if in-sync, 0 if not-in-sync, -EWOULDBLOCK
+ */
+static int userspace_in_sync(struct dm_dirty_log *log, region_t region,
+ int can_block)
+{
+ int r;
+ uint64_t region64 = region;
+ int64_t in_sync;
+ size_t rdata_size;
+ struct log_c *lc = log->context;
+
+ /*
+ * We can never respond directly - even if in_sync_hint is
+ * set. This is because another machine could see a device
+ * failure and mark the region out-of-sync. If we don't go
+ * to userspace to ask, we might think the region is in-sync
+ * and allow a read to pick up data that is stale. (This is
+ * very unlikely if a device actually fails; but it is very
+ * likely if a connection to one device from one machine fails.)
+ *
+ * There still might be a problem if the mirror caches the region
+ * state as in-sync... but then this call would not be made. So,
+ * that is a mirror problem.
+ */
+ if (!can_block)
+ return -EWOULDBLOCK;
+
+ rdata_size = sizeof(in_sync);
+ r = userspace_do_request(lc, lc->uuid, DM_ULOG_IN_SYNC,
+ (char *)&region64, sizeof(region64),
+ (char *)&in_sync, &rdata_size);
+ return (r) ? 0 : (int)in_sync;
+}
+
+/*
+ * userspace_flush
+ *
+ * This function is ok to block.
+ * The flush happens in two stages. First, it sends all
+ * clear/mark requests that are on the list. Then it
+ * tells the server to commit them. This gives the
+ * server a chance to optimise the commit, instead of
+ * doing it for every request.
+ *
+ * Additionally, we could implement another thread that
+ * sends the requests up to the server - reducing the
+ * load on flush. Then the flush would have less in
+ * the list and be responsible for the finishing commit.
+ *
+ * Returns: 0 on success, < 0 on failure
+ */
+static int userspace_flush(struct dm_dirty_log *log)
+{
+ int r = 0;
+ unsigned long flags;
+ struct log_c *lc = log->context;
+ LIST_HEAD(flush_list);
+ struct flush_entry *fe, *tmp_fe;
+
+ spin_lock_irqsave(&lc->flush_lock, flags);
+ list_splice_init(&lc->flush_list, &flush_list);
+ spin_unlock_irqrestore(&lc->flush_lock, flags);
+
+ if (list_empty(&flush_list))
+ return 0;
+
+ /*
+ * FIXME: Count up requests, group request types,
+ * allocate memory to stick all requests in and
+ * send to server in one go. Failing the allocation,
+ * do it one by one.
+ */
+
+ list_for_each_entry(fe, &flush_list, list) {
+ r = userspace_do_request(lc, lc->uuid, fe->type,
+ (char *)&fe->region,
+ sizeof(fe->region),
+ NULL, NULL);
+ if (r)
+ goto fail;
+ }
+
+ r = userspace_do_request(lc, lc->uuid, DM_ULOG_FLUSH,
+ NULL, 0, NULL, NULL);
+
+fail:
+ /*
+ * We can safely remove these entries, even if failure.
+ * Calling code will receive an error and will know that
+ * the log facility has failed.
+ */
+ list_for_each_entry_safe(fe, tmp_fe, &flush_list, list) {
+ list_del(&fe->list);
+ mempool_free(fe, flush_entry_pool);
+ }
+
+ if (r)
+ dm_table_event(lc->ti->table);
+
+ return r;
+}
+
+/*
+ * userspace_mark_region
+ *
+ * This function should avoid blocking unless absolutely required.
+ * (Memory allocation is valid for blocking.)
+ */
+static void userspace_mark_region(struct dm_dirty_log *log, region_t region)
+{
+ unsigned long flags;
+ struct log_c *lc = log->context;
+ struct flush_entry *fe;
+
+ /* Wait for an allocation, but _never_ fail */
+ fe = mempool_alloc(flush_entry_pool, GFP_NOIO);
+ BUG_ON(!fe);
+
+ spin_lock_irqsave(&lc->flush_lock, flags);
+ fe->type = DM_ULOG_MARK_REGION;
+ fe->region = region;
+ list_add(&fe->list, &lc->flush_list);
+ spin_unlock_irqrestore(&lc->flush_lock, flags);
+
+ return;
+}
+
+/*
+ * userspace_clear_region
+ *
+ * This function must not block.
+ * So, the alloc can't block. In the worst case, it is ok to
+ * fail. It would simply mean we can't clear the region.
+ * Does nothing to current sync context, but does mean
+ * the region will be re-sync'ed on a reload of the mirror
+ * even though it is in-sync.
+ */
+static void userspace_clear_region(struct dm_dirty_log *log, region_t region)
+{
+ unsigned long flags;
+ struct log_c *lc = log->context;
+ struct flush_entry *fe;
+
+ /*
+ * If we fail to allocate, we skip the clearing of
+ * the region. This doesn't hurt us in any way, except
+ * to cause the region to be resync'ed when the
+ * device is activated next time.
+ */
+ fe = mempool_alloc(flush_entry_pool, GFP_ATOMIC);
+ if (!fe) {
+ DMERR("Failed to allocate memory to clear region.");
+ return;
+ }
+
+ spin_lock_irqsave(&lc->flush_lock, flags);
+ fe->type = DM_ULOG_CLEAR_REGION;
+ fe->region = region;
+ list_add(&fe->list, &lc->flush_list);
+ spin_unlock_irqrestore(&lc->flush_lock, flags);
+
+ return;
+}
+
+/*
+ * userspace_get_resync_work
+ *
+ * Get a region that needs recovery. It is valid to return
+ * an error for this function.
+ *
+ * Returns: 1 if region filled, 0 if no work, <0 on error
+ */
+static int userspace_get_resync_work(struct dm_dirty_log *log, region_t *region)
+{
+ int r;
+ size_t rdata_size;
+ struct log_c *lc = log->context;
+ struct {
+ int64_t i; /* 64-bit for mix arch compatibility */
+ region_t r;
+ } pkg;
+
+ if (lc->in_sync_hint >= lc->region_count)
+ return 0;
+
+ rdata_size = sizeof(pkg);
+ r = userspace_do_request(lc, lc->uuid, DM_ULOG_GET_RESYNC_WORK,
+ NULL, 0,
+ (char *)&pkg, &rdata_size);
+
+ *region = pkg.r;
+ return (r) ? r : (int)pkg.i;
+}
+
+/*
+ * userspace_set_region_sync
+ *
+ * Set the sync status of a given region. This function
+ * must not fail.
+ */
+static void userspace_set_region_sync(struct dm_dirty_log *log,
+ region_t region, int in_sync)
+{
+ int r;
+ struct log_c *lc = log->context;
+ struct {
+ region_t r;
+ int64_t i;
+ } pkg;
+
+ pkg.r = region;
+ pkg.i = (int64_t)in_sync;
+
+ r = userspace_do_request(lc, lc->uuid, DM_ULOG_SET_REGION_SYNC,
+ (char *)&pkg, sizeof(pkg),
+ NULL, NULL);
+
+ /*
+ * It would be nice to be able to report failures.
+ * However, it is easy emough to detect and resolve.
+ */
+ return;
+}
+
+/*
+ * userspace_get_sync_count
+ *
+ * If there is any sort of failure when consulting the server,
+ * we assume that the sync count is zero.
+ *
+ * Returns: sync count on success, 0 on failure
+ */
+static region_t userspace_get_sync_count(struct dm_dirty_log *log)
+{
+ int r;
+ size_t rdata_size;
+ uint64_t sync_count;
+ struct log_c *lc = log->context;
+
+ rdata_size = sizeof(sync_count);
+ r = userspace_do_request(lc, lc->uuid, DM_ULOG_GET_SYNC_COUNT,
+ NULL, 0,
+ (char *)&sync_count, &rdata_size);
+
+ if (r)
+ return 0;
+
+ if (sync_count >= lc->region_count)
+ lc->in_sync_hint = lc->region_count;
+
+ return (region_t)sync_count;
+}
+
+/*
+ * userspace_status
+ *
+ * Returns: amount of space consumed
+ */
+static int userspace_status(struct dm_dirty_log *log, status_type_t status_type,
+ char *result, unsigned maxlen)
+{
+ int r = 0;
+ size_t sz = (size_t)maxlen;
+ struct log_c *lc = log->context;
+
+ switch (status_type) {
+ case STATUSTYPE_INFO:
+ r = userspace_do_request(lc, lc->uuid, DM_ULOG_STATUS_INFO,
+ NULL, 0,
+ result, &sz);
+
+ if (r) {
+ sz = 0;
+ DMEMIT("%s 1 COM_FAILURE", log->type->name);
+ }
+ break;
+ case STATUSTYPE_TABLE:
+ sz = 0;
+ DMEMIT("%s %u %s %s", log->type->name, lc->usr_argc + 1,
+ lc->uuid, lc->usr_argv_str);
+ break;
+ }
+ return (r) ? 0 : (int)sz;
+}
+
+/*
+ * userspace_is_remote_recovering
+ *
+ * Returns: 1 if region recovering, 0 otherwise
+ */
+static int userspace_is_remote_recovering(struct dm_dirty_log *log,
+ region_t region)
+{
+ int r;
+ uint64_t region64 = region;
+ struct log_c *lc = log->context;
+ static unsigned long long limit;
+ struct {
+ int64_t is_recovering;
+ uint64_t in_sync_hint;
+ } pkg;
+ size_t rdata_size = sizeof(pkg);
+
+ /*
+ * Once the mirror has been reported to be in-sync,
+ * it will never again ask for recovery work. So,
+ * we can safely say there is not a remote machine
+ * recovering if the device is in-sync. (in_sync_hint
+ * must be reset at resume time.)
+ */
+ if (region < lc->in_sync_hint)
+ return 0;
+ else if (jiffies < limit)
+ return 1;
+
+ limit = jiffies + (HZ / 4);
+ r = userspace_do_request(lc, lc->uuid, DM_ULOG_IS_REMOTE_RECOVERING,
+ (char *)&region64, sizeof(region64),
+ (char *)&pkg, &rdata_size);
+ if (r)
+ return 1;
+
+ lc->in_sync_hint = pkg.in_sync_hint;
+
+ return (int)pkg.is_recovering;
+}
+
+static struct dm_dirty_log_type _userspace_type = {
+ .name = "userspace",
+ .module = THIS_MODULE,
+ .ctr = userspace_ctr,
+ .dtr = userspace_dtr,
+ .presuspend = userspace_presuspend,
+ .postsuspend = userspace_postsuspend,
+ .resume = userspace_resume,
+ .get_region_size = userspace_get_region_size,
+ .is_clean = userspace_is_clean,
+ .in_sync = userspace_in_sync,
+ .flush = userspace_flush,
+ .mark_region = userspace_mark_region,
+ .clear_region = userspace_clear_region,
+ .get_resync_work = userspace_get_resync_work,
+ .set_region_sync = userspace_set_region_sync,
+ .get_sync_count = userspace_get_sync_count,
+ .status = userspace_status,
+ .is_remote_recovering = userspace_is_remote_recovering,
+};
+
+static int __init userspace_dirty_log_init(void)
+{
+ int r = 0;
+
+ flush_entry_pool = mempool_create(100, flush_entry_alloc,
+ flush_entry_free, NULL);
+
+ if (!flush_entry_pool) {
+ DMWARN("Unable to create flush_entry_pool: No memory.");
+ return -ENOMEM;
+ }
+
+ r = dm_ulog_tfr_init();
+ if (r) {
+ DMWARN("Unable to initialize userspace log communications");
+ mempool_destroy(flush_entry_pool);
+ return r;
+ }
+
+ r = dm_dirty_log_type_register(&_userspace_type);
+ if (r) {
+ DMWARN("Couldn't register userspace dirty log type");
+ dm_ulog_tfr_exit();
+ mempool_destroy(flush_entry_pool);
+ return r;
+ }
+
+ DMINFO("version 1.0.0 loaded");
+ return 0;
+}
+
+static void __exit userspace_dirty_log_exit(void)
+{
+ dm_dirty_log_type_unregister(&_userspace_type);
+ dm_ulog_tfr_exit();
+ mempool_destroy(flush_entry_pool);
+
+ DMINFO("version 1.0.0 unloaded");
+ return;
+}
+
+module_init(userspace_dirty_log_init);
+module_exit(userspace_dirty_log_exit);
+
+MODULE_DESCRIPTION(DM_NAME " userspace dirty log link");
+MODULE_AUTHOR("Jonathan Brassow <dm-devel@redhat.com>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/md/dm-log-userspace-transfer.c b/drivers/md/dm-log-userspace-transfer.c
new file mode 100644
index 000000000000..0ca1ee768a1f
--- /dev/null
+++ b/drivers/md/dm-log-userspace-transfer.c
@@ -0,0 +1,276 @@
+/*
+ * Copyright (C) 2006-2009 Red Hat, Inc.
+ *
+ * This file is released under the LGPL.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <net/sock.h>
+#include <linux/workqueue.h>
+#include <linux/connector.h>
+#include <linux/device-mapper.h>
+#include <linux/dm-log-userspace.h>
+
+#include "dm-log-userspace-transfer.h"
+
+static uint32_t dm_ulog_seq;
+
+/*
+ * Netlink/Connector is an unreliable protocol. How long should
+ * we wait for a response before assuming it was lost and retrying?
+ * (If we do receive a response after this time, it will be discarded
+ * and the response to the resent request will be waited for.
+ */
+#define DM_ULOG_RETRY_TIMEOUT (15 * HZ)
+
+/*
+ * Pre-allocated space for speed
+ */
+#define DM_ULOG_PREALLOCED_SIZE 512
+static struct cn_msg *prealloced_cn_msg;
+static struct dm_ulog_request *prealloced_ulog_tfr;
+
+static struct cb_id ulog_cn_id = {
+ .idx = CN_IDX_DM,
+ .val = CN_VAL_DM_USERSPACE_LOG
+};
+
+static DEFINE_MUTEX(dm_ulog_lock);
+
+struct receiving_pkg {
+ struct list_head list;
+ struct completion complete;
+
+ uint32_t seq;
+
+ int error;
+ size_t *data_size;
+ char *data;
+};
+
+static DEFINE_SPINLOCK(receiving_list_lock);
+static struct list_head receiving_list;
+
+static int dm_ulog_sendto_server(struct dm_ulog_request *tfr)
+{
+ int r;
+ struct cn_msg *msg = prealloced_cn_msg;
+
+ memset(msg, 0, sizeof(struct cn_msg));
+
+ msg->id.idx = ulog_cn_id.idx;
+ msg->id.val = ulog_cn_id.val;
+ msg->ack = 0;
+ msg->seq = tfr->seq;
+ msg->len = sizeof(struct dm_ulog_request) + tfr->data_size;
+
+ r = cn_netlink_send(msg, 0, gfp_any());
+
+ return r;
+}
+
+/*
+ * Parameters for this function can be either msg or tfr, but not
+ * both. This function fills in the reply for a waiting request.
+ * If just msg is given, then the reply is simply an ACK from userspace
+ * that the request was received.
+ *
+ * Returns: 0 on success, -ENOENT on failure
+ */
+static int fill_pkg(struct cn_msg *msg, struct dm_ulog_request *tfr)
+{
+ uint32_t rtn_seq = (msg) ? msg->seq : (tfr) ? tfr->seq : 0;
+ struct receiving_pkg *pkg;
+
+ /*
+ * The 'receiving_pkg' entries in this list are statically
+ * allocated on the stack in 'dm_consult_userspace'.
+ * Each process that is waiting for a reply from the user
+ * space server will have an entry in this list.
+ *
+ * We are safe to do it this way because the stack space
+ * is unique to each process, but still addressable by
+ * other processes.
+ */
+ list_for_each_entry(pkg, &receiving_list, list) {
+ if (rtn_seq != pkg->seq)
+ continue;
+
+ if (msg) {
+ pkg->error = -msg->ack;
+ /*
+ * If we are trying again, we will need to know our
+ * storage capacity. Otherwise, along with the
+ * error code, we make explicit that we have no data.
+ */
+ if (pkg->error != -EAGAIN)
+ *(pkg->data_size) = 0;
+ } else if (tfr->data_size > *(pkg->data_size)) {
+ DMERR("Insufficient space to receive package [%u] "
+ "(%u vs %lu)", tfr->request_type,
+ tfr->data_size, *(pkg->data_size));
+
+ *(pkg->data_size) = 0;
+ pkg->error = -ENOSPC;
+ } else {
+ pkg->error = tfr->error;
+ memcpy(pkg->data, tfr->data, tfr->data_size);
+ *(pkg->data_size) = tfr->data_size;
+ }
+ complete(&pkg->complete);
+ return 0;
+ }
+
+ return -ENOENT;
+}
+
+/*
+ * This is the connector callback that delivers data
+ * that was sent from userspace.
+ */
+static void cn_ulog_callback(void *data)
+{
+ struct cn_msg *msg = (struct cn_msg *)data;
+ struct dm_ulog_request *tfr = (struct dm_ulog_request *)(msg + 1);
+
+ spin_lock(&receiving_list_lock);
+ if (msg->len == 0)
+ fill_pkg(msg, NULL);
+ else if (msg->len < sizeof(*tfr))
+ DMERR("Incomplete message received (expected %u, got %u): [%u]",
+ (unsigned)sizeof(*tfr), msg->len, msg->seq);
+ else
+ fill_pkg(NULL, tfr);
+ spin_unlock(&receiving_list_lock);
+}
+
+/**
+ * dm_consult_userspace
+ * @uuid: log's uuid (must be DM_UUID_LEN in size)
+ * @request_type: found in include/linux/dm-log-userspace.h
+ * @data: data to tx to the server
+ * @data_size: size of data in bytes
+ * @rdata: place to put return data from server
+ * @rdata_size: value-result (amount of space given/amount of space used)
+ *
+ * rdata_size is undefined on failure.
+ *
+ * Memory used to communicate with userspace is zero'ed
+ * before populating to ensure that no unwanted bits leak
+ * from kernel space to user-space. All userspace log communications
+ * between kernel and user space go through this function.
+ *
+ * Returns: 0 on success, -EXXX on failure
+ **/
+int dm_consult_userspace(const char *uuid, int request_type,
+ char *data, size_t data_size,
+ char *rdata, size_t *rdata_size)
+{
+ int r = 0;
+ size_t dummy = 0;
+ int overhead_size =
+ sizeof(struct dm_ulog_request *) + sizeof(struct cn_msg);
+ struct dm_ulog_request *tfr = prealloced_ulog_tfr;
+ struct receiving_pkg pkg;
+
+ if (data_size > (DM_ULOG_PREALLOCED_SIZE - overhead_size)) {
+ DMINFO("Size of tfr exceeds preallocated size");
+ return -EINVAL;
+ }
+
+ if (!rdata_size)
+ rdata_size = &dummy;
+resend:
+ /*
+ * We serialize the sending of requests so we can
+ * use the preallocated space.
+ */
+ mutex_lock(&dm_ulog_lock);
+
+ memset(tfr, 0, DM_ULOG_PREALLOCED_SIZE - overhead_size);
+ memcpy(tfr->uuid, uuid, DM_UUID_LEN);
+ tfr->seq = dm_ulog_seq++;
+
+ /*
+ * Must be valid request type (all other bits set to
+ * zero). This reserves other bits for possible future
+ * use.
+ */
+ tfr->request_type = request_type & DM_ULOG_REQUEST_MASK;
+
+ tfr->data_size = data_size;
+ if (data && data_size)
+ memcpy(tfr->data, data, data_size);
+
+ memset(&pkg, 0, sizeof(pkg));
+ init_completion(&pkg.complete);
+ pkg.seq = tfr->seq;
+ pkg.data_size = rdata_size;
+ pkg.data = rdata;
+ spin_lock(&receiving_list_lock);
+ list_add(&(pkg.list), &receiving_list);
+ spin_unlock(&receiving_list_lock);
+
+ r = dm_ulog_sendto_server(tfr);
+
+ mutex_unlock(&dm_ulog_lock);
+
+ if (r) {
+ DMERR("Unable to send log request [%u] to userspace: %d",
+ request_type, r);
+ spin_lock(&receiving_list_lock);
+ list_del_init(&(pkg.list));
+ spin_unlock(&receiving_list_lock);
+
+ goto out;
+ }
+
+ r = wait_for_completion_timeout(&(pkg.complete), DM_ULOG_RETRY_TIMEOUT);
+ spin_lock(&receiving_list_lock);
+ list_del_init(&(pkg.list));
+ spin_unlock(&receiving_list_lock);
+ if (!r) {
+ DMWARN("[%s] Request timed out: [%u/%u] - retrying",
+ (strlen(uuid) > 8) ?
+ (uuid + (strlen(uuid) - 8)) : (uuid),
+ request_type, pkg.seq);
+ goto resend;
+ }
+
+ r = pkg.error;
+ if (r == -EAGAIN)
+ goto resend;
+
+out:
+ return r;
+}
+
+int dm_ulog_tfr_init(void)
+{
+ int r;
+ void *prealloced;
+
+ INIT_LIST_HEAD(&receiving_list);
+
+ prealloced = kmalloc(DM_ULOG_PREALLOCED_SIZE, GFP_KERNEL);
+ if (!prealloced)
+ return -ENOMEM;
+
+ prealloced_cn_msg = prealloced;
+ prealloced_ulog_tfr = prealloced + sizeof(struct cn_msg);
+
+ r = cn_add_callback(&ulog_cn_id, "dmlogusr", cn_ulog_callback);
+ if (r) {
+ cn_del_callback(&ulog_cn_id);
+ return r;
+ }
+
+ return 0;
+}
+
+void dm_ulog_tfr_exit(void)
+{
+ cn_del_callback(&ulog_cn_id);
+ kfree(prealloced_cn_msg);
+}
diff --git a/drivers/md/dm-log-userspace-transfer.h b/drivers/md/dm-log-userspace-transfer.h
new file mode 100644
index 000000000000..c26d8e4e2710
--- /dev/null
+++ b/drivers/md/dm-log-userspace-transfer.h
@@ -0,0 +1,18 @@
+/*
+ * Copyright (C) 2006-2009 Red Hat, Inc.
+ *
+ * This file is released under the LGPL.
+ */
+
+#ifndef __DM_LOG_USERSPACE_TRANSFER_H__
+#define __DM_LOG_USERSPACE_TRANSFER_H__
+
+#define DM_MSG_PREFIX "dm-log-userspace"
+
+int dm_ulog_tfr_init(void);
+void dm_ulog_tfr_exit(void);
+int dm_consult_userspace(const char *uuid, int request_type,
+ char *data, size_t data_size,
+ char *rdata, size_t *rdata_size);
+
+#endif /* __DM_LOG_USERSPACE_TRANSFER_H__ */
diff --git a/drivers/md/dm-log.c b/drivers/md/dm-log.c
index 6fa8ccf91c70..9443896ede07 100644
--- a/drivers/md/dm-log.c
+++ b/drivers/md/dm-log.c
@@ -412,11 +412,12 @@ static int create_log_context(struct dm_dirty_log *log, struct dm_target *ti,
/*
* Buffer holds both header and bitset.
*/
- buf_size = dm_round_up((LOG_OFFSET << SECTOR_SHIFT) +
- bitset_size,
- ti->limits.logical_block_size);
+ buf_size =
+ dm_round_up((LOG_OFFSET << SECTOR_SHIFT) + bitset_size,
+ bdev_logical_block_size(lc->header_location.
+ bdev));
- if (buf_size > dev->bdev->bd_inode->i_size) {
+ if (buf_size > i_size_read(dev->bdev->bd_inode)) {
DMWARN("log device %s too small: need %llu bytes",
dev->name, (unsigned long long)buf_size);
kfree(lc);
diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 6a386ab4f7eb..c70604a20897 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -8,7 +8,6 @@
#include <linux/device-mapper.h>
#include "dm-path-selector.h"
-#include "dm-bio-record.h"
#include "dm-uevent.h"
#include <linux/ctype.h>
@@ -35,6 +34,7 @@ struct pgpath {
struct dm_path path;
struct work_struct deactivate_path;
+ struct work_struct activate_path;
};
#define path_to_pgpath(__pgp) container_of((__pgp), struct pgpath, path)
@@ -64,8 +64,6 @@ struct multipath {
spinlock_t lock;
const char *hw_handler_name;
- struct work_struct activate_path;
- struct pgpath *pgpath_to_activate;
unsigned nr_priority_groups;
struct list_head priority_groups;
unsigned pg_init_required; /* pg_init needs calling? */
@@ -84,7 +82,7 @@ struct multipath {
unsigned pg_init_count; /* Number of times pg_init called */
struct work_struct process_queued_ios;
- struct bio_list queued_ios;
+ struct list_head queued_ios;
unsigned queue_size;
struct work_struct trigger_event;
@@ -101,7 +99,7 @@ struct multipath {
*/
struct dm_mpath_io {
struct pgpath *pgpath;
- struct dm_bio_details details;
+ size_t nr_bytes;
};
typedef int (*action_fn) (struct pgpath *pgpath);
@@ -128,6 +126,7 @@ static struct pgpath *alloc_pgpath(void)
if (pgpath) {
pgpath->is_active = 1;
INIT_WORK(&pgpath->deactivate_path, deactivate_path);
+ INIT_WORK(&pgpath->activate_path, activate_path);
}
return pgpath;
@@ -160,7 +159,6 @@ static struct priority_group *alloc_priority_group(void)
static void free_pgpaths(struct list_head *pgpaths, struct dm_target *ti)
{
- unsigned long flags;
struct pgpath *pgpath, *tmp;
struct multipath *m = ti->private;
@@ -169,10 +167,6 @@ static void free_pgpaths(struct list_head *pgpaths, struct dm_target *ti)
if (m->hw_handler_name)
scsi_dh_detach(bdev_get_queue(pgpath->path.dev->bdev));
dm_put_device(ti, pgpath->path.dev);
- spin_lock_irqsave(&m->lock, flags);
- if (m->pgpath_to_activate == pgpath)
- m->pgpath_to_activate = NULL;
- spin_unlock_irqrestore(&m->lock, flags);
free_pgpath(pgpath);
}
}
@@ -198,11 +192,11 @@ static struct multipath *alloc_multipath(struct dm_target *ti)
m = kzalloc(sizeof(*m), GFP_KERNEL);
if (m) {
INIT_LIST_HEAD(&m->priority_groups);
+ INIT_LIST_HEAD(&m->queued_ios);
spin_lock_init(&m->lock);
m->queue_io = 1;
INIT_WORK(&m->process_queued_ios, process_queued_ios);
INIT_WORK(&m->trigger_event, trigger_event);
- INIT_WORK(&m->activate_path, activate_path);
m->mpio_pool = mempool_create_slab_pool(MIN_IOS, _mpio_cache);
if (!m->mpio_pool) {
kfree(m);
@@ -250,11 +244,12 @@ static void __switch_pg(struct multipath *m, struct pgpath *pgpath)
m->pg_init_count = 0;
}
-static int __choose_path_in_pg(struct multipath *m, struct priority_group *pg)
+static int __choose_path_in_pg(struct multipath *m, struct priority_group *pg,
+ size_t nr_bytes)
{
struct dm_path *path;
- path = pg->ps.type->select_path(&pg->ps, &m->repeat_count);
+ path = pg->ps.type->select_path(&pg->ps, &m->repeat_count, nr_bytes);
if (!path)
return -ENXIO;
@@ -266,7 +261,7 @@ static int __choose_path_in_pg(struct multipath *m, struct priority_group *pg)
return 0;
}
-static void __choose_pgpath(struct multipath *m)
+static void __choose_pgpath(struct multipath *m, size_t nr_bytes)
{
struct priority_group *pg;
unsigned bypassed = 1;
@@ -278,12 +273,12 @@ static void __choose_pgpath(struct multipath *m)
if (m->next_pg) {
pg = m->next_pg;
m->next_pg = NULL;
- if (!__choose_path_in_pg(m, pg))
+ if (!__choose_path_in_pg(m, pg, nr_bytes))
return;
}
/* Don't change PG until it has no remaining paths */
- if (m->current_pg && !__choose_path_in_pg(m, m->current_pg))
+ if (m->current_pg && !__choose_path_in_pg(m, m->current_pg, nr_bytes))
return;
/*
@@ -295,7 +290,7 @@ static void __choose_pgpath(struct multipath *m)
list_for_each_entry(pg, &m->priority_groups, list) {
if (pg->bypassed == bypassed)
continue;
- if (!__choose_path_in_pg(m, pg))
+ if (!__choose_path_in_pg(m, pg, nr_bytes))
return;
}
} while (bypassed--);
@@ -322,19 +317,21 @@ static int __must_push_back(struct multipath *m)
dm_noflush_suspending(m->ti));
}
-static int map_io(struct multipath *m, struct bio *bio,
+static int map_io(struct multipath *m, struct request *clone,
struct dm_mpath_io *mpio, unsigned was_queued)
{
int r = DM_MAPIO_REMAPPED;
+ size_t nr_bytes = blk_rq_bytes(clone);
unsigned long flags;
struct pgpath *pgpath;
+ struct block_device *bdev;
spin_lock_irqsave(&m->lock, flags);
/* Do we need to select a new pgpath? */
if (!m->current_pgpath ||
(!m->queue_io && (m->repeat_count && --m->repeat_count == 0)))
- __choose_pgpath(m);
+ __choose_pgpath(m, nr_bytes);
pgpath = m->current_pgpath;
@@ -344,21 +341,28 @@ static int map_io(struct multipath *m, struct bio *bio,
if ((pgpath && m->queue_io) ||
(!pgpath && m->queue_if_no_path)) {
/* Queue for the daemon to resubmit */
- bio_list_add(&m->queued_ios, bio);
+ list_add_tail(&clone->queuelist, &m->queued_ios);
m->queue_size++;
if ((m->pg_init_required && !m->pg_init_in_progress) ||
!m->queue_io)
queue_work(kmultipathd, &m->process_queued_ios);
pgpath = NULL;
r = DM_MAPIO_SUBMITTED;
- } else if (pgpath)
- bio->bi_bdev = pgpath->path.dev->bdev;
- else if (__must_push_back(m))
+ } else if (pgpath) {
+ bdev = pgpath->path.dev->bdev;
+ clone->q = bdev_get_queue(bdev);
+ clone->rq_disk = bdev->bd_disk;
+ } else if (__must_push_back(m))
r = DM_MAPIO_REQUEUE;
else
r = -EIO; /* Failed */
mpio->pgpath = pgpath;
+ mpio->nr_bytes = nr_bytes;
+
+ if (r == DM_MAPIO_REMAPPED && pgpath->pg->ps.type->start_io)
+ pgpath->pg->ps.type->start_io(&pgpath->pg->ps, &pgpath->path,
+ nr_bytes);
spin_unlock_irqrestore(&m->lock, flags);
@@ -396,30 +400,31 @@ static void dispatch_queued_ios(struct multipath *m)
{
int r;
unsigned long flags;
- struct bio *bio = NULL, *next;
struct dm_mpath_io *mpio;
union map_info *info;
+ struct request *clone, *n;
+ LIST_HEAD(cl);
spin_lock_irqsave(&m->lock, flags);
- bio = bio_list_get(&m->queued_ios);
+ list_splice_init(&m->queued_ios, &cl);
spin_unlock_irqrestore(&m->lock, flags);
- while (bio) {
- next = bio->bi_next;
- bio->bi_next = NULL;
+ list_for_each_entry_safe(clone, n, &cl, queuelist) {
+ list_del_init(&clone->queuelist);
- info = dm_get_mapinfo(bio);
+ info = dm_get_rq_mapinfo(clone);
mpio = info->ptr;
- r = map_io(m, bio, mpio, 1);
- if (r < 0)
- bio_endio(bio, r);
- else if (r == DM_MAPIO_REMAPPED)
- generic_make_request(bio);
- else if (r == DM_MAPIO_REQUEUE)
- bio_endio(bio, -EIO);
-
- bio = next;
+ r = map_io(m, clone, mpio, 1);
+ if (r < 0) {
+ mempool_free(mpio, m->mpio_pool);
+ dm_kill_unmapped_request(clone, r);
+ } else if (r == DM_MAPIO_REMAPPED)
+ dm_dispatch_request(clone);
+ else if (r == DM_MAPIO_REQUEUE) {
+ mempool_free(mpio, m->mpio_pool);
+ dm_requeue_unmapped_request(clone);
+ }
}
}
@@ -427,8 +432,8 @@ static void process_queued_ios(struct work_struct *work)
{
struct multipath *m =
container_of(work, struct multipath, process_queued_ios);
- struct pgpath *pgpath = NULL;
- unsigned init_required = 0, must_queue = 1;
+ struct pgpath *pgpath = NULL, *tmp;
+ unsigned must_queue = 1;
unsigned long flags;
spin_lock_irqsave(&m->lock, flags);
@@ -437,7 +442,7 @@ static void process_queued_ios(struct work_struct *work)
goto out;
if (!m->current_pgpath)
- __choose_pgpath(m);
+ __choose_pgpath(m, 0);
pgpath = m->current_pgpath;
@@ -446,19 +451,15 @@ static void process_queued_ios(struct work_struct *work)
must_queue = 0;
if (m->pg_init_required && !m->pg_init_in_progress && pgpath) {
- m->pgpath_to_activate = pgpath;
m->pg_init_count++;
m->pg_init_required = 0;
- m->pg_init_in_progress = 1;
- init_required = 1;
+ list_for_each_entry(tmp, &pgpath->pg->pgpaths, list) {
+ if (queue_work(kmpath_handlerd, &tmp->activate_path))
+ m->pg_init_in_progress++;
+ }
}
-
out:
spin_unlock_irqrestore(&m->lock, flags);
-
- if (init_required)
- queue_work(kmpath_handlerd, &m->activate_path);
-
if (!must_queue)
dispatch_queued_ios(m);
}
@@ -553,6 +554,12 @@ static int parse_path_selector(struct arg_set *as, struct priority_group *pg,
return -EINVAL;
}
+ if (ps_argc > as->argc) {
+ dm_put_path_selector(pst);
+ ti->error = "not enough arguments for path selector";
+ return -EINVAL;
+ }
+
r = pst->create(&pg->ps, ps_argc, as->argv);
if (r) {
dm_put_path_selector(pst);
@@ -591,9 +598,20 @@ static struct pgpath *parse_path(struct arg_set *as, struct path_selector *ps,
}
if (m->hw_handler_name) {
- r = scsi_dh_attach(bdev_get_queue(p->path.dev->bdev),
- m->hw_handler_name);
+ struct request_queue *q = bdev_get_queue(p->path.dev->bdev);
+
+ r = scsi_dh_attach(q, m->hw_handler_name);
+ if (r == -EBUSY) {
+ /*
+ * Already attached to different hw_handler,
+ * try to reattach with correct one.
+ */
+ scsi_dh_detach(q);
+ r = scsi_dh_attach(q, m->hw_handler_name);
+ }
+
if (r < 0) {
+ ti->error = "error attaching hardware handler";
dm_put_device(ti, p->path.dev);
goto bad;
}
@@ -699,6 +717,11 @@ static int parse_hw_handler(struct arg_set *as, struct multipath *m)
if (!hw_argc)
return 0;
+ if (hw_argc > as->argc) {
+ ti->error = "not enough arguments for hardware handler";
+ return -EINVAL;
+ }
+
m->hw_handler_name = kstrdup(shift(as), GFP_KERNEL);
request_module("scsi_dh_%s", m->hw_handler_name);
if (scsi_dh_handler_exist(m->hw_handler_name) == 0) {
@@ -823,6 +846,8 @@ static int multipath_ctr(struct dm_target *ti, unsigned int argc,
goto bad;
}
+ ti->num_flush_requests = 1;
+
return 0;
bad:
@@ -836,25 +861,29 @@ static void multipath_dtr(struct dm_target *ti)
flush_workqueue(kmpath_handlerd);
flush_workqueue(kmultipathd);
+ flush_scheduled_work();
free_multipath(m);
}
/*
- * Map bios, recording original fields for later in case we have to resubmit
+ * Map cloned requests
*/
-static int multipath_map(struct dm_target *ti, struct bio *bio,
+static int multipath_map(struct dm_target *ti, struct request *clone,
union map_info *map_context)
{
int r;
struct dm_mpath_io *mpio;
struct multipath *m = (struct multipath *) ti->private;
- mpio = mempool_alloc(m->mpio_pool, GFP_NOIO);
- dm_bio_record(&mpio->details, bio);
+ mpio = mempool_alloc(m->mpio_pool, GFP_ATOMIC);
+ if (!mpio)
+ /* ENOMEM, requeue */
+ return DM_MAPIO_REQUEUE;
+ memset(mpio, 0, sizeof(*mpio));
map_context->ptr = mpio;
- bio->bi_rw |= (1 << BIO_RW_FAILFAST_TRANSPORT);
- r = map_io(m, bio, mpio, 0);
+ clone->cmd_flags |= REQ_FAILFAST_TRANSPORT;
+ r = map_io(m, clone, mpio, 0);
if (r < 0 || r == DM_MAPIO_REQUEUE)
mempool_free(mpio, m->mpio_pool);
@@ -924,9 +953,13 @@ static int reinstate_path(struct pgpath *pgpath)
pgpath->is_active = 1;
- m->current_pgpath = NULL;
- if (!m->nr_valid_paths++ && m->queue_size)
+ if (!m->nr_valid_paths++ && m->queue_size) {
+ m->current_pgpath = NULL;
queue_work(kmultipathd, &m->process_queued_ios);
+ } else if (m->hw_handler_name && (m->current_pg == pgpath->pg)) {
+ if (queue_work(kmpath_handlerd, &pgpath->activate_path))
+ m->pg_init_in_progress++;
+ }
dm_path_uevent(DM_UEVENT_PATH_REINSTATED, m->ti,
pgpath->path.dev->name, m->nr_valid_paths);
@@ -1102,87 +1135,70 @@ static void pg_init_done(struct dm_path *path, int errors)
spin_lock_irqsave(&m->lock, flags);
if (errors) {
- DMERR("Could not failover device. Error %d.", errors);
- m->current_pgpath = NULL;
- m->current_pg = NULL;
+ if (pgpath == m->current_pgpath) {
+ DMERR("Could not failover device. Error %d.", errors);
+ m->current_pgpath = NULL;
+ m->current_pg = NULL;
+ }
} else if (!m->pg_init_required) {
m->queue_io = 0;
pg->bypassed = 0;
}
- m->pg_init_in_progress = 0;
- queue_work(kmultipathd, &m->process_queued_ios);
+ m->pg_init_in_progress--;
+ if (!m->pg_init_in_progress)
+ queue_work(kmultipathd, &m->process_queued_ios);
spin_unlock_irqrestore(&m->lock, flags);
}
static void activate_path(struct work_struct *work)
{
int ret;
- struct multipath *m =
- container_of(work, struct multipath, activate_path);
- struct dm_path *path;
- unsigned long flags;
+ struct pgpath *pgpath =
+ container_of(work, struct pgpath, activate_path);
- spin_lock_irqsave(&m->lock, flags);
- path = &m->pgpath_to_activate->path;
- m->pgpath_to_activate = NULL;
- spin_unlock_irqrestore(&m->lock, flags);
- if (!path)
- return;
- ret = scsi_dh_activate(bdev_get_queue(path->dev->bdev));
- pg_init_done(path, ret);
+ ret = scsi_dh_activate(bdev_get_queue(pgpath->path.dev->bdev));
+ pg_init_done(&pgpath->path, ret);
}
/*
* end_io handling
*/
-static int do_end_io(struct multipath *m, struct bio *bio,
+static int do_end_io(struct multipath *m, struct request *clone,
int error, struct dm_mpath_io *mpio)
{
+ /*
+ * We don't queue any clone request inside the multipath target
+ * during end I/O handling, since those clone requests don't have
+ * bio clones. If we queue them inside the multipath target,
+ * we need to make bio clones, that requires memory allocation.
+ * (See drivers/md/dm.c:end_clone_bio() about why the clone requests
+ * don't have bio clones.)
+ * Instead of queueing the clone request here, we queue the original
+ * request into dm core, which will remake a clone request and
+ * clone bios for it and resubmit it later.
+ */
+ int r = DM_ENDIO_REQUEUE;
unsigned long flags;
- if (!error)
+ if (!error && !clone->errors)
return 0; /* I/O complete */
- if ((error == -EWOULDBLOCK) && bio_rw_ahead(bio))
- return error;
-
if (error == -EOPNOTSUPP)
return error;
- spin_lock_irqsave(&m->lock, flags);
- if (!m->nr_valid_paths) {
- if (__must_push_back(m)) {
- spin_unlock_irqrestore(&m->lock, flags);
- return DM_ENDIO_REQUEUE;
- } else if (!m->queue_if_no_path) {
- spin_unlock_irqrestore(&m->lock, flags);
- return -EIO;
- } else {
- spin_unlock_irqrestore(&m->lock, flags);
- goto requeue;
- }
- }
- spin_unlock_irqrestore(&m->lock, flags);
-
if (mpio->pgpath)
fail_path(mpio->pgpath);
- requeue:
- dm_bio_restore(&mpio->details, bio);
-
- /* queue for the daemon to resubmit or fail */
spin_lock_irqsave(&m->lock, flags);
- bio_list_add(&m->queued_ios, bio);
- m->queue_size++;
- if (!m->queue_io)
- queue_work(kmultipathd, &m->process_queued_ios);
+ if (!m->nr_valid_paths && !m->queue_if_no_path && !__must_push_back(m))
+ r = -EIO;
spin_unlock_irqrestore(&m->lock, flags);
- return DM_ENDIO_INCOMPLETE; /* io not complete */
+ return r;
}
-static int multipath_end_io(struct dm_target *ti, struct bio *bio,
+static int multipath_end_io(struct dm_target *ti, struct request *clone,
int error, union map_info *map_context)
{
struct multipath *m = ti->private;
@@ -1191,14 +1207,13 @@ static int multipath_end_io(struct dm_target *ti, struct bio *bio,
struct path_selector *ps;
int r;
- r = do_end_io(m, bio, error, mpio);
+ r = do_end_io(m, clone, error, mpio);
if (pgpath) {
ps = &pgpath->pg->ps;
if (ps->type->end_io)
- ps->type->end_io(ps, &pgpath->path);
+ ps->type->end_io(ps, &pgpath->path, mpio->nr_bytes);
}
- if (r != DM_ENDIO_INCOMPLETE)
- mempool_free(mpio, m->mpio_pool);
+ mempool_free(mpio, m->mpio_pool);
return r;
}
@@ -1411,7 +1426,7 @@ static int multipath_ioctl(struct dm_target *ti, unsigned int cmd,
spin_lock_irqsave(&m->lock, flags);
if (!m->current_pgpath)
- __choose_pgpath(m);
+ __choose_pgpath(m, 0);
if (m->current_pgpath) {
bdev = m->current_pgpath->path.dev->bdev;
@@ -1428,22 +1443,113 @@ static int multipath_ioctl(struct dm_target *ti, unsigned int cmd,
return r ? : __blkdev_driver_ioctl(bdev, mode, cmd, arg);
}
+static int multipath_iterate_devices(struct dm_target *ti,
+ iterate_devices_callout_fn fn, void *data)
+{
+ struct multipath *m = ti->private;
+ struct priority_group *pg;
+ struct pgpath *p;
+ int ret = 0;
+
+ list_for_each_entry(pg, &m->priority_groups, list) {
+ list_for_each_entry(p, &pg->pgpaths, list) {
+ ret = fn(ti, p->path.dev, ti->begin, data);
+ if (ret)
+ goto out;
+ }
+ }
+
+out:
+ return ret;
+}
+
+static int __pgpath_busy(struct pgpath *pgpath)
+{
+ struct request_queue *q = bdev_get_queue(pgpath->path.dev->bdev);
+
+ return dm_underlying_device_busy(q);
+}
+
+/*
+ * We return "busy", only when we can map I/Os but underlying devices
+ * are busy (so even if we map I/Os now, the I/Os will wait on
+ * the underlying queue).
+ * In other words, if we want to kill I/Os or queue them inside us
+ * due to map unavailability, we don't return "busy". Otherwise,
+ * dm core won't give us the I/Os and we can't do what we want.
+ */
+static int multipath_busy(struct dm_target *ti)
+{
+ int busy = 0, has_active = 0;
+ struct multipath *m = ti->private;
+ struct priority_group *pg;
+ struct pgpath *pgpath;
+ unsigned long flags;
+
+ spin_lock_irqsave(&m->lock, flags);
+
+ /* Guess which priority_group will be used at next mapping time */
+ if (unlikely(!m->current_pgpath && m->next_pg))
+ pg = m->next_pg;
+ else if (likely(m->current_pg))
+ pg = m->current_pg;
+ else
+ /*
+ * We don't know which pg will be used at next mapping time.
+ * We don't call __choose_pgpath() here to avoid to trigger
+ * pg_init just by busy checking.
+ * So we don't know whether underlying devices we will be using
+ * at next mapping time are busy or not. Just try mapping.
+ */
+ goto out;
+
+ /*
+ * If there is one non-busy active path at least, the path selector
+ * will be able to select it. So we consider such a pg as not busy.
+ */
+ busy = 1;
+ list_for_each_entry(pgpath, &pg->pgpaths, list)
+ if (pgpath->is_active) {
+ has_active = 1;
+
+ if (!__pgpath_busy(pgpath)) {
+ busy = 0;
+ break;
+ }
+ }
+
+ if (!has_active)
+ /*
+ * No active path in this pg, so this pg won't be used and
+ * the current_pg will be changed at next mapping time.
+ * We need to try mapping to determine it.
+ */
+ busy = 0;
+
+out:
+ spin_unlock_irqrestore(&m->lock, flags);
+
+ return busy;
+}
+
/*-----------------------------------------------------------------
* Module setup
*---------------------------------------------------------------*/
static struct target_type multipath_target = {
.name = "multipath",
- .version = {1, 0, 5},
+ .version = {1, 1, 0},
.module = THIS_MODULE,
.ctr = multipath_ctr,
.dtr = multipath_dtr,
- .map = multipath_map,
- .end_io = multipath_end_io,
+ .map_rq = multipath_map,
+ .rq_end_io = multipath_end_io,
.presuspend = multipath_presuspend,
.resume = multipath_resume,
.status = multipath_status,
.message = multipath_message,
.ioctl = multipath_ioctl,
+ .iterate_devices = multipath_iterate_devices,
+ .busy = multipath_busy,
};
static int __init dm_multipath_init(void)
diff --git a/drivers/md/dm-path-selector.h b/drivers/md/dm-path-selector.h
index 27357b85d73d..e7d1fa8b0459 100644
--- a/drivers/md/dm-path-selector.h
+++ b/drivers/md/dm-path-selector.h
@@ -56,7 +56,8 @@ struct path_selector_type {
* the path fails.
*/
struct dm_path *(*select_path) (struct path_selector *ps,
- unsigned *repeat_count);
+ unsigned *repeat_count,
+ size_t nr_bytes);
/*
* Notify the selector that a path has failed.
@@ -75,7 +76,10 @@ struct path_selector_type {
int (*status) (struct path_selector *ps, struct dm_path *path,
status_type_t type, char *result, unsigned int maxlen);
- int (*end_io) (struct path_selector *ps, struct dm_path *path);
+ int (*start_io) (struct path_selector *ps, struct dm_path *path,
+ size_t nr_bytes);
+ int (*end_io) (struct path_selector *ps, struct dm_path *path,
+ size_t nr_bytes);
};
/* Register a path selector */
diff --git a/drivers/md/dm-queue-length.c b/drivers/md/dm-queue-length.c
new file mode 100644
index 000000000000..f92b6cea9d9c
--- /dev/null
+++ b/drivers/md/dm-queue-length.c
@@ -0,0 +1,263 @@
+/*
+ * Copyright (C) 2004-2005 IBM Corp. All Rights Reserved.
+ * Copyright (C) 2006-2009 NEC Corporation.
+ *
+ * dm-queue-length.c
+ *
+ * Module Author: Stefan Bader, IBM
+ * Modified by: Kiyoshi Ueda, NEC
+ *
+ * This file is released under the GPL.
+ *
+ * queue-length path selector - choose a path with the least number of
+ * in-flight I/Os.
+ */
+
+#include "dm.h"
+#include "dm-path-selector.h"
+
+#include <linux/slab.h>
+#include <linux/ctype.h>
+#include <linux/errno.h>
+#include <linux/module.h>
+#include <asm/atomic.h>
+
+#define DM_MSG_PREFIX "multipath queue-length"
+#define QL_MIN_IO 128
+#define QL_VERSION "0.1.0"
+
+struct selector {
+ struct list_head valid_paths;
+ struct list_head failed_paths;
+};
+
+struct path_info {
+ struct list_head list;
+ struct dm_path *path;
+ unsigned repeat_count;
+ atomic_t qlen; /* the number of in-flight I/Os */
+};
+
+static struct selector *alloc_selector(void)
+{
+ struct selector *s = kmalloc(sizeof(*s), GFP_KERNEL);
+
+ if (s) {
+ INIT_LIST_HEAD(&s->valid_paths);
+ INIT_LIST_HEAD(&s->failed_paths);
+ }
+
+ return s;
+}
+
+static int ql_create(struct path_selector *ps, unsigned argc, char **argv)
+{
+ struct selector *s = alloc_selector();
+
+ if (!s)
+ return -ENOMEM;
+
+ ps->context = s;
+ return 0;
+}
+
+static void ql_free_paths(struct list_head *paths)
+{
+ struct path_info *pi, *next;
+
+ list_for_each_entry_safe(pi, next, paths, list) {
+ list_del(&pi->list);
+ kfree(pi);
+ }
+}
+
+static void ql_destroy(struct path_selector *ps)
+{
+ struct selector *s = ps->context;
+
+ ql_free_paths(&s->valid_paths);
+ ql_free_paths(&s->failed_paths);
+ kfree(s);
+ ps->context = NULL;
+}
+
+static int ql_status(struct path_selector *ps, struct dm_path *path,
+ status_type_t type, char *result, unsigned maxlen)
+{
+ unsigned sz = 0;
+ struct path_info *pi;
+
+ /* When called with NULL path, return selector status/args. */
+ if (!path)
+ DMEMIT("0 ");
+ else {
+ pi = path->pscontext;
+
+ switch (type) {
+ case STATUSTYPE_INFO:
+ DMEMIT("%d ", atomic_read(&pi->qlen));
+ break;
+ case STATUSTYPE_TABLE:
+ DMEMIT("%u ", pi->repeat_count);
+ break;
+ }
+ }
+
+ return sz;
+}
+
+static int ql_add_path(struct path_selector *ps, struct dm_path *path,
+ int argc, char **argv, char **error)
+{
+ struct selector *s = ps->context;
+ struct path_info *pi;
+ unsigned repeat_count = QL_MIN_IO;
+
+ /*
+ * Arguments: [<repeat_count>]
+ * <repeat_count>: The number of I/Os before switching path.
+ * If not given, default (QL_MIN_IO) is used.
+ */
+ if (argc > 1) {
+ *error = "queue-length ps: incorrect number of arguments";
+ return -EINVAL;
+ }
+
+ if ((argc == 1) && (sscanf(argv[0], "%u", &repeat_count) != 1)) {
+ *error = "queue-length ps: invalid repeat count";
+ return -EINVAL;
+ }
+
+ /* Allocate the path information structure */
+ pi = kmalloc(sizeof(*pi), GFP_KERNEL);
+ if (!pi) {
+ *error = "queue-length ps: Error allocating path information";
+ return -ENOMEM;
+ }
+
+ pi->path = path;
+ pi->repeat_count = repeat_count;
+ atomic_set(&pi->qlen, 0);
+
+ path->pscontext = pi;
+
+ list_add_tail(&pi->list, &s->valid_paths);
+
+ return 0;
+}
+
+static void ql_fail_path(struct path_selector *ps, struct dm_path *path)
+{
+ struct selector *s = ps->context;
+ struct path_info *pi = path->pscontext;
+
+ list_move(&pi->list, &s->failed_paths);
+}
+
+static int ql_reinstate_path(struct path_selector *ps, struct dm_path *path)
+{
+ struct selector *s = ps->context;
+ struct path_info *pi = path->pscontext;
+
+ list_move_tail(&pi->list, &s->valid_paths);
+
+ return 0;
+}
+
+/*
+ * Select a path having the minimum number of in-flight I/Os
+ */
+static struct dm_path *ql_select_path(struct path_selector *ps,
+ unsigned *repeat_count, size_t nr_bytes)
+{
+ struct selector *s = ps->context;
+ struct path_info *pi = NULL, *best = NULL;
+
+ if (list_empty(&s->valid_paths))
+ return NULL;
+
+ /* Change preferred (first in list) path to evenly balance. */
+ list_move_tail(s->valid_paths.next, &s->valid_paths);
+
+ list_for_each_entry(pi, &s->valid_paths, list) {
+ if (!best ||
+ (atomic_read(&pi->qlen) < atomic_read(&best->qlen)))
+ best = pi;
+
+ if (!atomic_read(&best->qlen))
+ break;
+ }
+
+ if (!best)
+ return NULL;
+
+ *repeat_count = best->repeat_count;
+
+ return best->path;
+}
+
+static int ql_start_io(struct path_selector *ps, struct dm_path *path,
+ size_t nr_bytes)
+{
+ struct path_info *pi = path->pscontext;
+
+ atomic_inc(&pi->qlen);
+
+ return 0;
+}
+
+static int ql_end_io(struct path_selector *ps, struct dm_path *path,
+ size_t nr_bytes)
+{
+ struct path_info *pi = path->pscontext;
+
+ atomic_dec(&pi->qlen);
+
+ return 0;
+}
+
+static struct path_selector_type ql_ps = {
+ .name = "queue-length",
+ .module = THIS_MODULE,
+ .table_args = 1,
+ .info_args = 1,
+ .create = ql_create,
+ .destroy = ql_destroy,
+ .status = ql_status,
+ .add_path = ql_add_path,
+ .fail_path = ql_fail_path,
+ .reinstate_path = ql_reinstate_path,
+ .select_path = ql_select_path,
+ .start_io = ql_start_io,
+ .end_io = ql_end_io,
+};
+
+static int __init dm_ql_init(void)
+{
+ int r = dm_register_path_selector(&ql_ps);
+
+ if (r < 0)
+ DMERR("register failed %d", r);
+
+ DMINFO("version " QL_VERSION " loaded");
+
+ return r;
+}
+
+static void __exit dm_ql_exit(void)
+{
+ int r = dm_unregister_path_selector(&ql_ps);
+
+ if (r < 0)
+ DMERR("unregister failed %d", r);
+}
+
+module_init(dm_ql_init);
+module_exit(dm_ql_exit);
+
+MODULE_AUTHOR("Stefan Bader <Stefan.Bader at de.ibm.com>");
+MODULE_DESCRIPTION(
+ "(C) Copyright IBM Corp. 2004,2005 All Rights Reserved.\n"
+ DM_NAME " path selector to balance the number of in-flight I/Os"
+);
+MODULE_LICENSE("GPL");
diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c
index 076fbb4e967a..ce8868c768cc 100644
--- a/drivers/md/dm-raid1.c
+++ b/drivers/md/dm-raid1.c
@@ -1283,9 +1283,23 @@ static int mirror_status(struct dm_target *ti, status_type_t type,
return 0;
}
+static int mirror_iterate_devices(struct dm_target *ti,
+ iterate_devices_callout_fn fn, void *data)
+{
+ struct mirror_set *ms = ti->private;
+ int ret = 0;
+ unsigned i;
+
+ for (i = 0; !ret && i < ms->nr_mirrors; i++)
+ ret = fn(ti, ms->mirror[i].dev,
+ ms->mirror[i].offset, data);
+
+ return ret;
+}
+
static struct target_type mirror_target = {
.name = "mirror",
- .version = {1, 0, 20},
+ .version = {1, 12, 0},
.module = THIS_MODULE,
.ctr = mirror_ctr,
.dtr = mirror_dtr,
@@ -1295,6 +1309,7 @@ static struct target_type mirror_target = {
.postsuspend = mirror_postsuspend,
.resume = mirror_resume,
.status = mirror_status,
+ .iterate_devices = mirror_iterate_devices,
};
static int __init dm_mirror_init(void)
diff --git a/drivers/md/dm-region-hash.c b/drivers/md/dm-region-hash.c
index 7b899be0b087..36dbe29f2fd6 100644
--- a/drivers/md/dm-region-hash.c
+++ b/drivers/md/dm-region-hash.c
@@ -283,7 +283,7 @@ static struct dm_region *__rh_alloc(struct dm_region_hash *rh, region_t region)
nreg = mempool_alloc(rh->region_pool, GFP_ATOMIC);
if (unlikely(!nreg))
- nreg = kmalloc(sizeof(*nreg), GFP_NOIO);
+ nreg = kmalloc(sizeof(*nreg), GFP_NOIO | __GFP_NOFAIL);
nreg->state = rh->log->type->in_sync(rh->log, region, 1) ?
DM_RH_CLEAN : DM_RH_NOSYNC;
diff --git a/drivers/md/dm-round-robin.c b/drivers/md/dm-round-robin.c
index cdfbf65b28cb..24752f449bef 100644
--- a/drivers/md/dm-round-robin.c
+++ b/drivers/md/dm-round-robin.c
@@ -161,7 +161,7 @@ static int rr_reinstate_path(struct path_selector *ps, struct dm_path *p)
}
static struct dm_path *rr_select_path(struct path_selector *ps,
- unsigned *repeat_count)
+ unsigned *repeat_count, size_t nr_bytes)
{
struct selector *s = (struct selector *) ps->context;
struct path_info *pi = NULL;
diff --git a/drivers/md/dm-service-time.c b/drivers/md/dm-service-time.c
new file mode 100644
index 000000000000..cfa668f46c40
--- /dev/null
+++ b/drivers/md/dm-service-time.c
@@ -0,0 +1,339 @@
+/*
+ * Copyright (C) 2007-2009 NEC Corporation. All Rights Reserved.
+ *
+ * Module Author: Kiyoshi Ueda
+ *
+ * This file is released under the GPL.
+ *
+ * Throughput oriented path selector.
+ */
+
+#include "dm.h"
+#include "dm-path-selector.h"
+
+#define DM_MSG_PREFIX "multipath service-time"
+#define ST_MIN_IO 1
+#define ST_MAX_RELATIVE_THROUGHPUT 100
+#define ST_MAX_RELATIVE_THROUGHPUT_SHIFT 7
+#define ST_MAX_INFLIGHT_SIZE ((size_t)-1 >> ST_MAX_RELATIVE_THROUGHPUT_SHIFT)
+#define ST_VERSION "0.2.0"
+
+struct selector {
+ struct list_head valid_paths;
+ struct list_head failed_paths;
+};
+
+struct path_info {
+ struct list_head list;
+ struct dm_path *path;
+ unsigned repeat_count;
+ unsigned relative_throughput;
+ atomic_t in_flight_size; /* Total size of in-flight I/Os */
+};
+
+static struct selector *alloc_selector(void)
+{
+ struct selector *s = kmalloc(sizeof(*s), GFP_KERNEL);
+
+ if (s) {
+ INIT_LIST_HEAD(&s->valid_paths);
+ INIT_LIST_HEAD(&s->failed_paths);
+ }
+
+ return s;
+}
+
+static int st_create(struct path_selector *ps, unsigned argc, char **argv)
+{
+ struct selector *s = alloc_selector();
+
+ if (!s)
+ return -ENOMEM;
+
+ ps->context = s;
+ return 0;
+}
+
+static void free_paths(struct list_head *paths)
+{
+ struct path_info *pi, *next;
+
+ list_for_each_entry_safe(pi, next, paths, list) {
+ list_del(&pi->list);
+ kfree(pi);
+ }
+}
+
+static void st_destroy(struct path_selector *ps)
+{
+ struct selector *s = ps->context;
+
+ free_paths(&s->valid_paths);
+ free_paths(&s->failed_paths);
+ kfree(s);
+ ps->context = NULL;
+}
+
+static int st_status(struct path_selector *ps, struct dm_path *path,
+ status_type_t type, char *result, unsigned maxlen)
+{
+ unsigned sz = 0;
+ struct path_info *pi;
+
+ if (!path)
+ DMEMIT("0 ");
+ else {
+ pi = path->pscontext;
+
+ switch (type) {
+ case STATUSTYPE_INFO:
+ DMEMIT("%d %u ", atomic_read(&pi->in_flight_size),
+ pi->relative_throughput);
+ break;
+ case STATUSTYPE_TABLE:
+ DMEMIT("%u %u ", pi->repeat_count,
+ pi->relative_throughput);
+ break;
+ }
+ }
+
+ return sz;
+}
+
+static int st_add_path(struct path_selector *ps, struct dm_path *path,
+ int argc, char **argv, char **error)
+{
+ struct selector *s = ps->context;
+ struct path_info *pi;
+ unsigned repeat_count = ST_MIN_IO;
+ unsigned relative_throughput = 1;
+
+ /*
+ * Arguments: [<repeat_count> [<relative_throughput>]]
+ * <repeat_count>: The number of I/Os before switching path.
+ * If not given, default (ST_MIN_IO) is used.
+ * <relative_throughput>: The relative throughput value of
+ * the path among all paths in the path-group.
+ * The valid range: 0-<ST_MAX_RELATIVE_THROUGHPUT>
+ * If not given, minimum value '1' is used.
+ * If '0' is given, the path isn't selected while
+ * other paths having a positive value are
+ * available.
+ */
+ if (argc > 2) {
+ *error = "service-time ps: incorrect number of arguments";
+ return -EINVAL;
+ }
+
+ if (argc && (sscanf(argv[0], "%u", &repeat_count) != 1)) {
+ *error = "service-time ps: invalid repeat count";
+ return -EINVAL;
+ }
+
+ if ((argc == 2) &&
+ (sscanf(argv[1], "%u", &relative_throughput) != 1 ||
+ relative_throughput > ST_MAX_RELATIVE_THROUGHPUT)) {
+ *error = "service-time ps: invalid relative_throughput value";
+ return -EINVAL;
+ }
+
+ /* allocate the path */
+ pi = kmalloc(sizeof(*pi), GFP_KERNEL);
+ if (!pi) {
+ *error = "service-time ps: Error allocating path context";
+ return -ENOMEM;
+ }
+
+ pi->path = path;
+ pi->repeat_count = repeat_count;
+ pi->relative_throughput = relative_throughput;
+ atomic_set(&pi->in_flight_size, 0);
+
+ path->pscontext = pi;
+
+ list_add_tail(&pi->list, &s->valid_paths);
+
+ return 0;
+}
+
+static void st_fail_path(struct path_selector *ps, struct dm_path *path)
+{
+ struct selector *s = ps->context;
+ struct path_info *pi = path->pscontext;
+
+ list_move(&pi->list, &s->failed_paths);
+}
+
+static int st_reinstate_path(struct path_selector *ps, struct dm_path *path)
+{
+ struct selector *s = ps->context;
+ struct path_info *pi = path->pscontext;
+
+ list_move_tail(&pi->list, &s->valid_paths);
+
+ return 0;
+}
+
+/*
+ * Compare the estimated service time of 2 paths, pi1 and pi2,
+ * for the incoming I/O.
+ *
+ * Returns:
+ * < 0 : pi1 is better
+ * 0 : no difference between pi1 and pi2
+ * > 0 : pi2 is better
+ *
+ * Description:
+ * Basically, the service time is estimated by:
+ * ('pi->in-flight-size' + 'incoming') / 'pi->relative_throughput'
+ * To reduce the calculation, some optimizations are made.
+ * (See comments inline)
+ */
+static int st_compare_load(struct path_info *pi1, struct path_info *pi2,
+ size_t incoming)
+{
+ size_t sz1, sz2, st1, st2;
+
+ sz1 = atomic_read(&pi1->in_flight_size);
+ sz2 = atomic_read(&pi2->in_flight_size);
+
+ /*
+ * Case 1: Both have same throughput value. Choose less loaded path.
+ */
+ if (pi1->relative_throughput == pi2->relative_throughput)
+ return sz1 - sz2;
+
+ /*
+ * Case 2a: Both have same load. Choose higher throughput path.
+ * Case 2b: One path has no throughput value. Choose the other one.
+ */
+ if (sz1 == sz2 ||
+ !pi1->relative_throughput || !pi2->relative_throughput)
+ return pi2->relative_throughput - pi1->relative_throughput;
+
+ /*
+ * Case 3: Calculate service time. Choose faster path.
+ * Service time using pi1:
+ * st1 = (sz1 + incoming) / pi1->relative_throughput
+ * Service time using pi2:
+ * st2 = (sz2 + incoming) / pi2->relative_throughput
+ *
+ * To avoid the division, transform the expression to use
+ * multiplication.
+ * Because ->relative_throughput > 0 here, if st1 < st2,
+ * the expressions below are the same meaning:
+ * (sz1 + incoming) / pi1->relative_throughput <
+ * (sz2 + incoming) / pi2->relative_throughput
+ * (sz1 + incoming) * pi2->relative_throughput <
+ * (sz2 + incoming) * pi1->relative_throughput
+ * So use the later one.
+ */
+ sz1 += incoming;
+ sz2 += incoming;
+ if (unlikely(sz1 >= ST_MAX_INFLIGHT_SIZE ||
+ sz2 >= ST_MAX_INFLIGHT_SIZE)) {
+ /*
+ * Size may be too big for multiplying pi->relative_throughput
+ * and overflow.
+ * To avoid the overflow and mis-selection, shift down both.
+ */
+ sz1 >>= ST_MAX_RELATIVE_THROUGHPUT_SHIFT;
+ sz2 >>= ST_MAX_RELATIVE_THROUGHPUT_SHIFT;
+ }
+ st1 = sz1 * pi2->relative_throughput;
+ st2 = sz2 * pi1->relative_throughput;
+ if (st1 != st2)
+ return st1 - st2;
+
+ /*
+ * Case 4: Service time is equal. Choose higher throughput path.
+ */
+ return pi2->relative_throughput - pi1->relative_throughput;
+}
+
+static struct dm_path *st_select_path(struct path_selector *ps,
+ unsigned *repeat_count, size_t nr_bytes)
+{
+ struct selector *s = ps->context;
+ struct path_info *pi = NULL, *best = NULL;
+
+ if (list_empty(&s->valid_paths))
+ return NULL;
+
+ /* Change preferred (first in list) path to evenly balance. */
+ list_move_tail(s->valid_paths.next, &s->valid_paths);
+
+ list_for_each_entry(pi, &s->valid_paths, list)
+ if (!best || (st_compare_load(pi, best, nr_bytes) < 0))
+ best = pi;
+
+ if (!best)
+ return NULL;
+
+ *repeat_count = best->repeat_count;
+
+ return best->path;
+}
+
+static int st_start_io(struct path_selector *ps, struct dm_path *path,
+ size_t nr_bytes)
+{
+ struct path_info *pi = path->pscontext;
+
+ atomic_add(nr_bytes, &pi->in_flight_size);
+
+ return 0;
+}
+
+static int st_end_io(struct path_selector *ps, struct dm_path *path,
+ size_t nr_bytes)
+{
+ struct path_info *pi = path->pscontext;
+
+ atomic_sub(nr_bytes, &pi->in_flight_size);
+
+ return 0;
+}
+
+static struct path_selector_type st_ps = {
+ .name = "service-time",
+ .module = THIS_MODULE,
+ .table_args = 2,
+ .info_args = 2,
+ .create = st_create,
+ .destroy = st_destroy,
+ .status = st_status,
+ .add_path = st_add_path,
+ .fail_path = st_fail_path,
+ .reinstate_path = st_reinstate_path,
+ .select_path = st_select_path,
+ .start_io = st_start_io,
+ .end_io = st_end_io,
+};
+
+static int __init dm_st_init(void)
+{
+ int r = dm_register_path_selector(&st_ps);
+
+ if (r < 0)
+ DMERR("register failed %d", r);
+
+ DMINFO("version " ST_VERSION " loaded");
+
+ return r;
+}
+
+static void __exit dm_st_exit(void)
+{
+ int r = dm_unregister_path_selector(&st_ps);
+
+ if (r < 0)
+ DMERR("unregister failed %d", r);
+}
+
+module_init(dm_st_init);
+module_exit(dm_st_exit);
+
+MODULE_DESCRIPTION(DM_NAME " throughput oriented path selector");
+MODULE_AUTHOR("Kiyoshi Ueda <k-ueda@ct.jp.nec.com>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/md/dm-snap-persistent.c b/drivers/md/dm-snap-persistent.c
index 2662a41337e7..6e3fe4f14934 100644
--- a/drivers/md/dm-snap-persistent.c
+++ b/drivers/md/dm-snap-persistent.c
@@ -636,7 +636,7 @@ static void persistent_commit_exception(struct dm_exception_store *store,
/*
* Commit exceptions to disk.
*/
- if (ps->valid && area_io(ps, WRITE))
+ if (ps->valid && area_io(ps, WRITE_BARRIER))
ps->valid = 0;
/*
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index d73f17fc7778..d573165cd2b7 100644
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -678,6 +678,7 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv)
ti->private = s;
ti->split_io = s->store->chunk_size;
+ ti->num_flush_requests = 1;
return 0;
@@ -1030,6 +1031,11 @@ static int snapshot_map(struct dm_target *ti, struct bio *bio,
chunk_t chunk;
struct dm_snap_pending_exception *pe = NULL;
+ if (unlikely(bio_empty_barrier(bio))) {
+ bio->bi_bdev = s->store->cow->bdev;
+ return DM_MAPIO_REMAPPED;
+ }
+
chunk = sector_to_chunk(s->store, bio->bi_sector);
/* Full snapshots are not usable */
@@ -1338,6 +1344,8 @@ static int origin_ctr(struct dm_target *ti, unsigned int argc, char **argv)
}
ti->private = dev;
+ ti->num_flush_requests = 1;
+
return 0;
}
@@ -1353,6 +1361,9 @@ static int origin_map(struct dm_target *ti, struct bio *bio,
struct dm_dev *dev = ti->private;
bio->bi_bdev = dev->bdev;
+ if (unlikely(bio_empty_barrier(bio)))
+ return DM_MAPIO_REMAPPED;
+
/* Only tell snapshots if this is a write */
return (bio_rw(bio) == WRITE) ? do_origin(dev, bio) : DM_MAPIO_REMAPPED;
}
diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index 41569bc60abc..b240e85ae39a 100644
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -167,6 +167,7 @@ static int stripe_ctr(struct dm_target *ti, unsigned int argc, char **argv)
sc->stripes = stripes;
sc->stripe_width = width;
ti->split_io = chunk_size;
+ ti->num_flush_requests = stripes;
sc->chunk_mask = ((sector_t) chunk_size) - 1;
for (sc->chunk_shift = 0; chunk_size; sc->chunk_shift++)
@@ -211,10 +212,18 @@ static int stripe_map(struct dm_target *ti, struct bio *bio,
union map_info *map_context)
{
struct stripe_c *sc = (struct stripe_c *) ti->private;
+ sector_t offset, chunk;
+ uint32_t stripe;
- sector_t offset = bio->bi_sector - ti->begin;
- sector_t chunk = offset >> sc->chunk_shift;
- uint32_t stripe = sector_div(chunk, sc->stripes);
+ if (unlikely(bio_empty_barrier(bio))) {
+ BUG_ON(map_context->flush_request >= sc->stripes);
+ bio->bi_bdev = sc->stripe[map_context->flush_request].dev->bdev;
+ return DM_MAPIO_REMAPPED;
+ }
+
+ offset = bio->bi_sector - ti->begin;
+ chunk = offset >> sc->chunk_shift;
+ stripe = sector_div(chunk, sc->stripes);
bio->bi_bdev = sc->stripe[stripe].dev->bdev;
bio->bi_sector = sc->stripe[stripe].physical_start +
@@ -304,15 +313,31 @@ static int stripe_end_io(struct dm_target *ti, struct bio *bio,
return error;
}
+static int stripe_iterate_devices(struct dm_target *ti,
+ iterate_devices_callout_fn fn, void *data)
+{
+ struct stripe_c *sc = ti->private;
+ int ret = 0;
+ unsigned i = 0;
+
+ do
+ ret = fn(ti, sc->stripe[i].dev,
+ sc->stripe[i].physical_start, data);
+ while (!ret && ++i < sc->stripes);
+
+ return ret;
+}
+
static struct target_type stripe_target = {
.name = "striped",
- .version = {1, 1, 0},
+ .version = {1, 2, 0},
.module = THIS_MODULE,
.ctr = stripe_ctr,
.dtr = stripe_dtr,
.map = stripe_map,
.end_io = stripe_end_io,
.status = stripe_status,
+ .iterate_devices = stripe_iterate_devices,
};
int __init dm_stripe_init(void)
diff --git a/drivers/md/dm-sysfs.c b/drivers/md/dm-sysfs.c
index a2a45e6c7c8b..4b045903a4e2 100644
--- a/drivers/md/dm-sysfs.c
+++ b/drivers/md/dm-sysfs.c
@@ -57,12 +57,21 @@ static ssize_t dm_attr_uuid_show(struct mapped_device *md, char *buf)
return strlen(buf);
}
+static ssize_t dm_attr_suspended_show(struct mapped_device *md, char *buf)
+{
+ sprintf(buf, "%d\n", dm_suspended(md));
+
+ return strlen(buf);
+}
+
static DM_ATTR_RO(name);
static DM_ATTR_RO(uuid);
+static DM_ATTR_RO(suspended);
static struct attribute *dm_attrs[] = {
&dm_attr_name.attr,
&dm_attr_uuid.attr,
+ &dm_attr_suspended.attr,
NULL,
};
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index e9a73bb242b0..4899ebe767c8 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -41,6 +41,7 @@
struct dm_table {
struct mapped_device *md;
atomic_t holders;
+ unsigned type;
/* btree table */
unsigned int depth;
@@ -62,15 +63,11 @@ struct dm_table {
/* a list of devices used by this table */
struct list_head devices;
- /*
- * These are optimistic limits taken from all the
- * targets, some targets will need smaller limits.
- */
- struct io_restrictions limits;
-
/* events get handed up using this callback */
void (*event_fn)(void *);
void *event_context;
+
+ struct dm_md_mempools *mempools;
};
/*
@@ -89,43 +86,6 @@ static unsigned int int_log(unsigned int n, unsigned int base)
}
/*
- * Returns the minimum that is _not_ zero, unless both are zero.
- */
-#define min_not_zero(l, r) (l == 0) ? r : ((r == 0) ? l : min(l, r))
-
-/*
- * Combine two io_restrictions, always taking the lower value.
- */
-static void combine_restrictions_low(struct io_restrictions *lhs,
- struct io_restrictions *rhs)
-{
- lhs->max_sectors =
- min_not_zero(lhs->max_sectors, rhs->max_sectors);
-
- lhs->max_phys_segments =
- min_not_zero(lhs->max_phys_segments, rhs->max_phys_segments);
-
- lhs->max_hw_segments =
- min_not_zero(lhs->max_hw_segments, rhs->max_hw_segments);
-
- lhs->logical_block_size = max(lhs->logical_block_size,
- rhs->logical_block_size);
-
- lhs->max_segment_size =
- min_not_zero(lhs->max_segment_size, rhs->max_segment_size);
-
- lhs->max_hw_sectors =
- min_not_zero(lhs->max_hw_sectors, rhs->max_hw_sectors);
-
- lhs->seg_boundary_mask =
- min_not_zero(lhs->seg_boundary_mask, rhs->seg_boundary_mask);
-
- lhs->bounce_pfn = min_not_zero(lhs->bounce_pfn, rhs->bounce_pfn);
-
- lhs->no_cluster |= rhs->no_cluster;
-}
-
-/*
* Calculate the index of the child node of the n'th node k'th key.
*/
static inline unsigned int get_child(unsigned int n, unsigned int k)
@@ -267,6 +227,8 @@ static void free_devices(struct list_head *devices)
list_for_each_safe(tmp, next, devices) {
struct dm_dev_internal *dd =
list_entry(tmp, struct dm_dev_internal, list);
+ DMWARN("dm_table_destroy: dm_put_device call missing for %s",
+ dd->dm_dev.name);
kfree(dd);
}
}
@@ -296,12 +258,10 @@ void dm_table_destroy(struct dm_table *t)
vfree(t->highs);
/* free the device list */
- if (t->devices.next != &t->devices) {
- DMWARN("devices still present during destroy: "
- "dm_table_remove_device calls missing");
-
+ if (t->devices.next != &t->devices)
free_devices(&t->devices);
- }
+
+ dm_free_md_mempools(t->mempools);
kfree(t);
}
@@ -385,15 +345,48 @@ static void close_dev(struct dm_dev_internal *d, struct mapped_device *md)
/*
* If possible, this checks an area of a destination device is valid.
*/
-static int check_device_area(struct dm_dev_internal *dd, sector_t start,
- sector_t len)
+static int device_area_is_valid(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, void *data)
{
- sector_t dev_size = dd->dm_dev.bdev->bd_inode->i_size >> SECTOR_SHIFT;
+ struct queue_limits *limits = data;
+ struct block_device *bdev = dev->bdev;
+ sector_t dev_size =
+ i_size_read(bdev->bd_inode) >> SECTOR_SHIFT;
+ unsigned short logical_block_size_sectors =
+ limits->logical_block_size >> SECTOR_SHIFT;
+ char b[BDEVNAME_SIZE];
if (!dev_size)
return 1;
- return ((start < dev_size) && (len <= (dev_size - start)));
+ if ((start >= dev_size) || (start + ti->len > dev_size)) {
+ DMWARN("%s: %s too small for target",
+ dm_device_name(ti->table->md), bdevname(bdev, b));
+ return 0;
+ }
+
+ if (logical_block_size_sectors <= 1)
+ return 1;
+
+ if (start & (logical_block_size_sectors - 1)) {
+ DMWARN("%s: start=%llu not aligned to h/w "
+ "logical block size %hu of %s",
+ dm_device_name(ti->table->md),
+ (unsigned long long)start,
+ limits->logical_block_size, bdevname(bdev, b));
+ return 0;
+ }
+
+ if (ti->len & (logical_block_size_sectors - 1)) {
+ DMWARN("%s: len=%llu not aligned to h/w "
+ "logical block size %hu of %s",
+ dm_device_name(ti->table->md),
+ (unsigned long long)ti->len,
+ limits->logical_block_size, bdevname(bdev, b));
+ return 0;
+ }
+
+ return 1;
}
/*
@@ -479,38 +472,32 @@ static int __table_get_device(struct dm_table *t, struct dm_target *ti,
}
atomic_inc(&dd->count);
- if (!check_device_area(dd, start, len)) {
- DMWARN("device %s too small for target", path);
- dm_put_device(ti, &dd->dm_dev);
- return -EINVAL;
- }
-
*result = &dd->dm_dev;
-
return 0;
}
-void dm_set_device_limits(struct dm_target *ti, struct block_device *bdev)
+/*
+ * Returns the minimum that is _not_ zero, unless both are zero.
+ */
+#define min_not_zero(l, r) (l == 0) ? r : ((r == 0) ? l : min(l, r))
+
+int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, void *data)
{
+ struct queue_limits *limits = data;
+ struct block_device *bdev = dev->bdev;
struct request_queue *q = bdev_get_queue(bdev);
- struct io_restrictions *rs = &ti->limits;
char b[BDEVNAME_SIZE];
if (unlikely(!q)) {
DMWARN("%s: Cannot set limits for nonexistent device %s",
dm_device_name(ti->table->md), bdevname(bdev, b));
- return;
+ return 0;
}
- /*
- * Combine the device limits low.
- *
- * FIXME: if we move an io_restriction struct
- * into q this would just be a call to
- * combine_restrictions_low()
- */
- rs->max_sectors =
- min_not_zero(rs->max_sectors, queue_max_sectors(q));
+ if (blk_stack_limits(limits, &q->limits, start) < 0)
+ DMWARN("%s: target device %s is misaligned",
+ dm_device_name(ti->table->md), bdevname(bdev, b));
/*
* Check if merge fn is supported.
@@ -519,48 +506,21 @@ void dm_set_device_limits(struct dm_target *ti, struct block_device *bdev)
*/
if (q->merge_bvec_fn && !ti->type->merge)
- rs->max_sectors =
- min_not_zero(rs->max_sectors,
+ limits->max_sectors =
+ min_not_zero(limits->max_sectors,
(unsigned int) (PAGE_SIZE >> 9));
-
- rs->max_phys_segments =
- min_not_zero(rs->max_phys_segments,
- queue_max_phys_segments(q));
-
- rs->max_hw_segments =
- min_not_zero(rs->max_hw_segments, queue_max_hw_segments(q));
-
- rs->logical_block_size = max(rs->logical_block_size,
- queue_logical_block_size(q));
-
- rs->max_segment_size =
- min_not_zero(rs->max_segment_size, queue_max_segment_size(q));
-
- rs->max_hw_sectors =
- min_not_zero(rs->max_hw_sectors, queue_max_hw_sectors(q));
-
- rs->seg_boundary_mask =
- min_not_zero(rs->seg_boundary_mask,
- queue_segment_boundary(q));
-
- rs->bounce_pfn = min_not_zero(rs->bounce_pfn, queue_bounce_pfn(q));
-
- rs->no_cluster |= !test_bit(QUEUE_FLAG_CLUSTER, &q->queue_flags);
+ return 0;
}
EXPORT_SYMBOL_GPL(dm_set_device_limits);
int dm_get_device(struct dm_target *ti, const char *path, sector_t start,
sector_t len, fmode_t mode, struct dm_dev **result)
{
- int r = __table_get_device(ti->table, ti, path,
- start, len, mode, result);
-
- if (!r)
- dm_set_device_limits(ti, (*result)->bdev);
-
- return r;
+ return __table_get_device(ti->table, ti, path,
+ start, len, mode, result);
}
+
/*
* Decrement a devices use count and remove it if necessary.
*/
@@ -675,24 +635,78 @@ int dm_split_args(int *argc, char ***argvp, char *input)
return 0;
}
-static void check_for_valid_limits(struct io_restrictions *rs)
+/*
+ * Impose necessary and sufficient conditions on a devices's table such
+ * that any incoming bio which respects its logical_block_size can be
+ * processed successfully. If it falls across the boundary between
+ * two or more targets, the size of each piece it gets split into must
+ * be compatible with the logical_block_size of the target processing it.
+ */
+static int validate_hardware_logical_block_alignment(struct dm_table *table,
+ struct queue_limits *limits)
{
- if (!rs->max_sectors)
- rs->max_sectors = SAFE_MAX_SECTORS;
- if (!rs->max_hw_sectors)
- rs->max_hw_sectors = SAFE_MAX_SECTORS;
- if (!rs->max_phys_segments)
- rs->max_phys_segments = MAX_PHYS_SEGMENTS;
- if (!rs->max_hw_segments)
- rs->max_hw_segments = MAX_HW_SEGMENTS;
- if (!rs->logical_block_size)
- rs->logical_block_size = 1 << SECTOR_SHIFT;
- if (!rs->max_segment_size)
- rs->max_segment_size = MAX_SEGMENT_SIZE;
- if (!rs->seg_boundary_mask)
- rs->seg_boundary_mask = BLK_SEG_BOUNDARY_MASK;
- if (!rs->bounce_pfn)
- rs->bounce_pfn = -1;
+ /*
+ * This function uses arithmetic modulo the logical_block_size
+ * (in units of 512-byte sectors).
+ */
+ unsigned short device_logical_block_size_sects =
+ limits->logical_block_size >> SECTOR_SHIFT;
+
+ /*
+ * Offset of the start of the next table entry, mod logical_block_size.
+ */
+ unsigned short next_target_start = 0;
+
+ /*
+ * Given an aligned bio that extends beyond the end of a
+ * target, how many sectors must the next target handle?
+ */
+ unsigned short remaining = 0;
+
+ struct dm_target *uninitialized_var(ti);
+ struct queue_limits ti_limits;
+ unsigned i = 0;
+
+ /*
+ * Check each entry in the table in turn.
+ */
+ while (i < dm_table_get_num_targets(table)) {
+ ti = dm_table_get_target(table, i++);
+
+ blk_set_default_limits(&ti_limits);
+
+ /* combine all target devices' limits */
+ if (ti->type->iterate_devices)
+ ti->type->iterate_devices(ti, dm_set_device_limits,
+ &ti_limits);
+
+ /*
+ * If the remaining sectors fall entirely within this
+ * table entry are they compatible with its logical_block_size?
+ */
+ if (remaining < ti->len &&
+ remaining & ((ti_limits.logical_block_size >>
+ SECTOR_SHIFT) - 1))
+ break; /* Error */
+
+ next_target_start =
+ (unsigned short) ((next_target_start + ti->len) &
+ (device_logical_block_size_sects - 1));
+ remaining = next_target_start ?
+ device_logical_block_size_sects - next_target_start : 0;
+ }
+
+ if (remaining) {
+ DMWARN("%s: table line %u (start sect %llu len %llu) "
+ "not aligned to h/w logical block size %hu",
+ dm_device_name(table->md), i,
+ (unsigned long long) ti->begin,
+ (unsigned long long) ti->len,
+ limits->logical_block_size);
+ return -EINVAL;
+ }
+
+ return 0;
}
int dm_table_add_target(struct dm_table *t, const char *type,
@@ -747,9 +761,6 @@ int dm_table_add_target(struct dm_table *t, const char *type,
t->highs[t->num_targets++] = tgt->begin + tgt->len - 1;
- /* FIXME: the plan is to combine high here and then have
- * the merge fn apply the target level restrictions. */
- combine_restrictions_low(&t->limits, &tgt->limits);
return 0;
bad:
@@ -758,6 +769,104 @@ int dm_table_add_target(struct dm_table *t, const char *type,
return r;
}
+int dm_table_set_type(struct dm_table *t)
+{
+ unsigned i;
+ unsigned bio_based = 0, request_based = 0;
+ struct dm_target *tgt;
+ struct dm_dev_internal *dd;
+ struct list_head *devices;
+
+ for (i = 0; i < t->num_targets; i++) {
+ tgt = t->targets + i;
+ if (dm_target_request_based(tgt))
+ request_based = 1;
+ else
+ bio_based = 1;
+
+ if (bio_based && request_based) {
+ DMWARN("Inconsistent table: different target types"
+ " can't be mixed up");
+ return -EINVAL;
+ }
+ }
+
+ if (bio_based) {
+ /* We must use this table as bio-based */
+ t->type = DM_TYPE_BIO_BASED;
+ return 0;
+ }
+
+ BUG_ON(!request_based); /* No targets in this table */
+
+ /* Non-request-stackable devices can't be used for request-based dm */
+ devices = dm_table_get_devices(t);
+ list_for_each_entry(dd, devices, list) {
+ if (!blk_queue_stackable(bdev_get_queue(dd->dm_dev.bdev))) {
+ DMWARN("table load rejected: including"
+ " non-request-stackable devices");
+ return -EINVAL;
+ }
+ }
+
+ /*
+ * Request-based dm supports only tables that have a single target now.
+ * To support multiple targets, request splitting support is needed,
+ * and that needs lots of changes in the block-layer.
+ * (e.g. request completion process for partial completion.)
+ */
+ if (t->num_targets > 1) {
+ DMWARN("Request-based dm doesn't support multiple targets yet");
+ return -EINVAL;
+ }
+
+ t->type = DM_TYPE_REQUEST_BASED;
+
+ return 0;
+}
+
+unsigned dm_table_get_type(struct dm_table *t)
+{
+ return t->type;
+}
+
+bool dm_table_bio_based(struct dm_table *t)
+{
+ return dm_table_get_type(t) == DM_TYPE_BIO_BASED;
+}
+
+bool dm_table_request_based(struct dm_table *t)
+{
+ return dm_table_get_type(t) == DM_TYPE_REQUEST_BASED;
+}
+
+int dm_table_alloc_md_mempools(struct dm_table *t)
+{
+ unsigned type = dm_table_get_type(t);
+
+ if (unlikely(type == DM_TYPE_NONE)) {
+ DMWARN("no table type is set, can't allocate mempools");
+ return -EINVAL;
+ }
+
+ t->mempools = dm_alloc_md_mempools(type);
+ if (!t->mempools)
+ return -ENOMEM;
+
+ return 0;
+}
+
+void dm_table_free_md_mempools(struct dm_table *t)
+{
+ dm_free_md_mempools(t->mempools);
+ t->mempools = NULL;
+}
+
+struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t)
+{
+ return t->mempools;
+}
+
static int setup_indexes(struct dm_table *t)
{
int i;
@@ -792,8 +901,6 @@ int dm_table_complete(struct dm_table *t)
int r = 0;
unsigned int leaf_nodes;
- check_for_valid_limits(&t->limits);
-
/* how many indexes will the btree have ? */
leaf_nodes = dm_div_up(t->num_targets, KEYS_PER_NODE);
t->depth = 1 + int_log(leaf_nodes, CHILDREN_PER_NODE);
@@ -869,6 +976,57 @@ struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector)
}
/*
+ * Establish the new table's queue_limits and validate them.
+ */
+int dm_calculate_queue_limits(struct dm_table *table,
+ struct queue_limits *limits)
+{
+ struct dm_target *uninitialized_var(ti);
+ struct queue_limits ti_limits;
+ unsigned i = 0;
+
+ blk_set_default_limits(limits);
+
+ while (i < dm_table_get_num_targets(table)) {
+ blk_set_default_limits(&ti_limits);
+
+ ti = dm_table_get_target(table, i++);
+
+ if (!ti->type->iterate_devices)
+ goto combine_limits;
+
+ /*
+ * Combine queue limits of all the devices this target uses.
+ */
+ ti->type->iterate_devices(ti, dm_set_device_limits,
+ &ti_limits);
+
+ /*
+ * Check each device area is consistent with the target's
+ * overall queue limits.
+ */
+ if (!ti->type->iterate_devices(ti, device_area_is_valid,
+ &ti_limits))
+ return -EINVAL;
+
+combine_limits:
+ /*
+ * Merge this target's queue limits into the overall limits
+ * for the table.
+ */
+ if (blk_stack_limits(limits, &ti_limits, 0) < 0)
+ DMWARN("%s: target device "
+ "(start sect %llu len %llu) "
+ "is misaligned",
+ dm_device_name(table->md),
+ (unsigned long long) ti->begin,
+ (unsigned long long) ti->len);
+ }
+
+ return validate_hardware_logical_block_alignment(table, limits);
+}
+
+/*
* Set the integrity profile for this device if all devices used have
* matching profiles.
*/
@@ -907,27 +1065,42 @@ no_integrity:
return;
}
-void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q)
+void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
+ struct queue_limits *limits)
{
/*
- * Make sure we obey the optimistic sub devices
- * restrictions.
+ * Each target device in the table has a data area that should normally
+ * be aligned such that the DM device's alignment_offset is 0.
+ * FIXME: Propagate alignment_offsets up the stack and warn of
+ * sub-optimal or inconsistent settings.
+ */
+ limits->alignment_offset = 0;
+ limits->misaligned = 0;
+
+ /*
+ * Copy table's limits to the DM device's request_queue
*/
- blk_queue_max_sectors(q, t->limits.max_sectors);
- blk_queue_max_phys_segments(q, t->limits.max_phys_segments);
- blk_queue_max_hw_segments(q, t->limits.max_hw_segments);
- blk_queue_logical_block_size(q, t->limits.logical_block_size);
- blk_queue_max_segment_size(q, t->limits.max_segment_size);
- blk_queue_max_hw_sectors(q, t->limits.max_hw_sectors);
- blk_queue_segment_boundary(q, t->limits.seg_boundary_mask);
- blk_queue_bounce_limit(q, t->limits.bounce_pfn);
-
- if (t->limits.no_cluster)
+ q->limits = *limits;
+
+ if (limits->no_cluster)
queue_flag_clear_unlocked(QUEUE_FLAG_CLUSTER, q);
else
queue_flag_set_unlocked(QUEUE_FLAG_CLUSTER, q);
dm_table_set_integrity(t);
+
+ /*
+ * QUEUE_FLAG_STACKABLE must be set after all queue settings are
+ * visible to other CPUs because, once the flag is set, incoming bios
+ * are processed by request-based dm, which refers to the queue
+ * settings.
+ * Until the flag set, bios are passed to bio-based dm and queued to
+ * md->deferred where queue settings are not needed yet.
+ * Those bios are passed to request-based dm at the resume time.
+ */
+ smp_mb();
+ if (dm_table_request_based(t))
+ queue_flag_set_unlocked(QUEUE_FLAG_STACKABLE, q);
}
unsigned int dm_table_get_num_targets(struct dm_table *t)
@@ -1023,6 +1196,20 @@ int dm_table_any_congested(struct dm_table *t, int bdi_bits)
return r;
}
+int dm_table_any_busy_target(struct dm_table *t)
+{
+ unsigned i;
+ struct dm_target *ti;
+
+ for (i = 0; i < t->num_targets; i++) {
+ ti = t->targets + i;
+ if (ti->type->busy && ti->type->busy(ti))
+ return 1;
+ }
+
+ return 0;
+}
+
void dm_table_unplug_all(struct dm_table *t)
{
struct dm_dev_internal *dd;
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 48db308fae67..3c6d4ee8921d 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -24,6 +24,13 @@
#define DM_MSG_PREFIX "core"
+/*
+ * Cookies are numeric values sent with CHANGE and REMOVE
+ * uevents while resuming, removing or renaming the device.
+ */
+#define DM_COOKIE_ENV_VAR_NAME "DM_COOKIE"
+#define DM_COOKIE_LENGTH 24
+
static const char *_name = DM_NAME;
static unsigned int major = 0;
@@ -71,7 +78,7 @@ struct dm_rq_target_io {
*/
struct dm_rq_clone_bio_info {
struct bio *orig;
- struct request *rq;
+ struct dm_rq_target_io *tio;
};
union map_info *dm_get_mapinfo(struct bio *bio)
@@ -81,6 +88,14 @@ union map_info *dm_get_mapinfo(struct bio *bio)
return NULL;
}
+union map_info *dm_get_rq_mapinfo(struct request *rq)
+{
+ if (rq && rq->end_io_data)
+ return &((struct dm_rq_target_io *)rq->end_io_data)->info;
+ return NULL;
+}
+EXPORT_SYMBOL_GPL(dm_get_rq_mapinfo);
+
#define MINOR_ALLOCED ((void *)-1)
/*
@@ -157,13 +172,31 @@ struct mapped_device {
* freeze/thaw support require holding onto a super block
*/
struct super_block *frozen_sb;
- struct block_device *suspended_bdev;
+ struct block_device *bdev;
/* forced geometry settings */
struct hd_geometry geometry;
+ /* marker of flush suspend for request-based dm */
+ struct request suspend_rq;
+
+ /* For saving the address of __make_request for request based dm */
+ make_request_fn *saved_make_request_fn;
+
/* sysfs handle */
struct kobject kobj;
+
+ /* zero-length barrier that will be cloned and submitted to targets */
+ struct bio barrier_bio;
+};
+
+/*
+ * For mempools pre-allocation at the table loading time.
+ */
+struct dm_md_mempools {
+ mempool_t *io_pool;
+ mempool_t *tio_pool;
+ struct bio_set *bs;
};
#define MIN_IOS 256
@@ -391,14 +424,29 @@ static void free_io(struct mapped_device *md, struct dm_io *io)
mempool_free(io, md->io_pool);
}
-static struct dm_target_io *alloc_tio(struct mapped_device *md)
+static void free_tio(struct mapped_device *md, struct dm_target_io *tio)
{
- return mempool_alloc(md->tio_pool, GFP_NOIO);
+ mempool_free(tio, md->tio_pool);
}
-static void free_tio(struct mapped_device *md, struct dm_target_io *tio)
+static struct dm_rq_target_io *alloc_rq_tio(struct mapped_device *md)
{
- mempool_free(tio, md->tio_pool);
+ return mempool_alloc(md->tio_pool, GFP_ATOMIC);
+}
+
+static void free_rq_tio(struct dm_rq_target_io *tio)
+{
+ mempool_free(tio, tio->md->tio_pool);
+}
+
+static struct dm_rq_clone_bio_info *alloc_bio_info(struct mapped_device *md)
+{
+ return mempool_alloc(md->io_pool, GFP_ATOMIC);
+}
+
+static void free_bio_info(struct dm_rq_clone_bio_info *info)
+{
+ mempool_free(info, info->tio->md->io_pool);
}
static void start_io_acct(struct dm_io *io)
@@ -464,12 +512,13 @@ static void queue_io(struct mapped_device *md, struct bio *bio)
struct dm_table *dm_get_table(struct mapped_device *md)
{
struct dm_table *t;
+ unsigned long flags;
- read_lock(&md->map_lock);
+ read_lock_irqsave(&md->map_lock, flags);
t = md->map;
if (t)
dm_table_get(t);
- read_unlock(&md->map_lock);
+ read_unlock_irqrestore(&md->map_lock, flags);
return t;
}
@@ -536,9 +585,11 @@ static void dec_pending(struct dm_io *io, int error)
* Target requested pushing back the I/O.
*/
spin_lock_irqsave(&md->deferred_lock, flags);
- if (__noflush_suspending(md))
- bio_list_add_head(&md->deferred, io->bio);
- else
+ if (__noflush_suspending(md)) {
+ if (!bio_barrier(io->bio))
+ bio_list_add_head(&md->deferred,
+ io->bio);
+ } else
/* noflush suspend was interrupted. */
io->error = -EIO;
spin_unlock_irqrestore(&md->deferred_lock, flags);
@@ -553,7 +604,8 @@ static void dec_pending(struct dm_io *io, int error)
* a per-device variable for error reporting.
* Note that you can't touch the bio after end_io_acct
*/
- md->barrier_error = io_error;
+ if (!md->barrier_error && io_error != -EOPNOTSUPP)
+ md->barrier_error = io_error;
end_io_acct(io);
} else {
end_io_acct(io);
@@ -607,6 +659,262 @@ static void clone_endio(struct bio *bio, int error)
dec_pending(io, error);
}
+/*
+ * Partial completion handling for request-based dm
+ */
+static void end_clone_bio(struct bio *clone, int error)
+{
+ struct dm_rq_clone_bio_info *info = clone->bi_private;
+ struct dm_rq_target_io *tio = info->tio;
+ struct bio *bio = info->orig;
+ unsigned int nr_bytes = info->orig->bi_size;
+
+ bio_put(clone);
+
+ if (tio->error)
+ /*
+ * An error has already been detected on the request.
+ * Once error occurred, just let clone->end_io() handle
+ * the remainder.
+ */
+ return;
+ else if (error) {
+ /*
+ * Don't notice the error to the upper layer yet.
+ * The error handling decision is made by the target driver,
+ * when the request is completed.
+ */
+ tio->error = error;
+ return;
+ }
+
+ /*
+ * I/O for the bio successfully completed.
+ * Notice the data completion to the upper layer.
+ */
+
+ /*
+ * bios are processed from the head of the list.
+ * So the completing bio should always be rq->bio.
+ * If it's not, something wrong is happening.
+ */
+ if (tio->orig->bio != bio)
+ DMERR("bio completion is going in the middle of the request");
+
+ /*
+ * Update the original request.
+ * Do not use blk_end_request() here, because it may complete
+ * the original request before the clone, and break the ordering.
+ */
+ blk_update_request(tio->orig, 0, nr_bytes);
+}
+
+/*
+ * Don't touch any member of the md after calling this function because
+ * the md may be freed in dm_put() at the end of this function.
+ * Or do dm_get() before calling this function and dm_put() later.
+ */
+static void rq_completed(struct mapped_device *md, int run_queue)
+{
+ int wakeup_waiters = 0;
+ struct request_queue *q = md->queue;
+ unsigned long flags;
+
+ spin_lock_irqsave(q->queue_lock, flags);
+ if (!queue_in_flight(q))
+ wakeup_waiters = 1;
+ spin_unlock_irqrestore(q->queue_lock, flags);
+
+ /* nudge anyone waiting on suspend queue */
+ if (wakeup_waiters)
+ wake_up(&md->wait);
+
+ if (run_queue)
+ blk_run_queue(q);
+
+ /*
+ * dm_put() must be at the end of this function. See the comment above
+ */
+ dm_put(md);
+}
+
+static void dm_unprep_request(struct request *rq)
+{
+ struct request *clone = rq->special;
+ struct dm_rq_target_io *tio = clone->end_io_data;
+
+ rq->special = NULL;
+ rq->cmd_flags &= ~REQ_DONTPREP;
+
+ blk_rq_unprep_clone(clone);
+ free_rq_tio(tio);
+}
+
+/*
+ * Requeue the original request of a clone.
+ */
+void dm_requeue_unmapped_request(struct request *clone)
+{
+ struct dm_rq_target_io *tio = clone->end_io_data;
+ struct mapped_device *md = tio->md;
+ struct request *rq = tio->orig;
+ struct request_queue *q = rq->q;
+ unsigned long flags;
+
+ dm_unprep_request(rq);
+
+ spin_lock_irqsave(q->queue_lock, flags);
+ if (elv_queue_empty(q))
+ blk_plug_device(q);
+ blk_requeue_request(q, rq);
+ spin_unlock_irqrestore(q->queue_lock, flags);
+
+ rq_completed(md, 0);
+}
+EXPORT_SYMBOL_GPL(dm_requeue_unmapped_request);
+
+static void __stop_queue(struct request_queue *q)
+{
+ blk_stop_queue(q);
+}
+
+static void stop_queue(struct request_queue *q)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(q->queue_lock, flags);
+ __stop_queue(q);
+ spin_unlock_irqrestore(q->queue_lock, flags);
+}
+
+static void __start_queue(struct request_queue *q)
+{
+ if (blk_queue_stopped(q))
+ blk_start_queue(q);
+}
+
+static void start_queue(struct request_queue *q)
+{
+ unsigned long flags;
+
+ spin_lock_irqsave(q->queue_lock, flags);
+ __start_queue(q);
+ spin_unlock_irqrestore(q->queue_lock, flags);
+}
+
+/*
+ * Complete the clone and the original request.
+ * Must be called without queue lock.
+ */
+static void dm_end_request(struct request *clone, int error)
+{
+ struct dm_rq_target_io *tio = clone->end_io_data;
+ struct mapped_device *md = tio->md;
+ struct request *rq = tio->orig;
+
+ if (blk_pc_request(rq)) {
+ rq->errors = clone->errors;
+ rq->resid_len = clone->resid_len;
+
+ if (rq->sense)
+ /*
+ * We are using the sense buffer of the original
+ * request.
+ * So setting the length of the sense data is enough.
+ */
+ rq->sense_len = clone->sense_len;
+ }
+
+ BUG_ON(clone->bio);
+ free_rq_tio(tio);
+
+ blk_end_request_all(rq, error);
+
+ rq_completed(md, 1);
+}
+
+/*
+ * Request completion handler for request-based dm
+ */
+static void dm_softirq_done(struct request *rq)
+{
+ struct request *clone = rq->completion_data;
+ struct dm_rq_target_io *tio = clone->end_io_data;
+ dm_request_endio_fn rq_end_io = tio->ti->type->rq_end_io;
+ int error = tio->error;
+
+ if (!(rq->cmd_flags & REQ_FAILED) && rq_end_io)
+ error = rq_end_io(tio->ti, clone, error, &tio->info);
+
+ if (error <= 0)
+ /* The target wants to complete the I/O */
+ dm_end_request(clone, error);
+ else if (error == DM_ENDIO_INCOMPLETE)
+ /* The target will handle the I/O */
+ return;
+ else if (error == DM_ENDIO_REQUEUE)
+ /* The target wants to requeue the I/O */
+ dm_requeue_unmapped_request(clone);
+ else {
+ DMWARN("unimplemented target endio return value: %d", error);
+ BUG();
+ }
+}
+
+/*
+ * Complete the clone and the original request with the error status
+ * through softirq context.
+ */
+static void dm_complete_request(struct request *clone, int error)
+{
+ struct dm_rq_target_io *tio = clone->end_io_data;
+ struct request *rq = tio->orig;
+
+ tio->error = error;
+ rq->completion_data = clone;
+ blk_complete_request(rq);
+}
+
+/*
+ * Complete the not-mapped clone and the original request with the error status
+ * through softirq context.
+ * Target's rq_end_io() function isn't called.
+ * This may be used when the target's map_rq() function fails.
+ */
+void dm_kill_unmapped_request(struct request *clone, int error)
+{
+ struct dm_rq_target_io *tio = clone->end_io_data;
+ struct request *rq = tio->orig;
+
+ rq->cmd_flags |= REQ_FAILED;
+ dm_complete_request(clone, error);
+}
+EXPORT_SYMBOL_GPL(dm_kill_unmapped_request);
+
+/*
+ * Called with the queue lock held
+ */
+static void end_clone_request(struct request *clone, int error)
+{
+ /*
+ * For just cleaning up the information of the queue in which
+ * the clone was dispatched.
+ * The clone is *NOT* freed actually here because it is alloced from
+ * dm own mempool and REQ_ALLOCED isn't set in clone->cmd_flags.
+ */
+ __blk_put_request(clone->q, clone);
+
+ /*
+ * Actual request completion is done in a softirq context which doesn't
+ * hold the queue lock. Otherwise, deadlock could occur because:
+ * - another request may be submitted by the upper level driver
+ * of the stacking during the completion
+ * - the submission which requires queue lock may be done
+ * against this queue
+ */
+ dm_complete_request(clone, error);
+}
+
static sector_t max_io_len(struct mapped_device *md,
sector_t sector, struct dm_target *ti)
{
@@ -634,11 +942,6 @@ static void __map_bio(struct dm_target *ti, struct bio *clone,
sector_t sector;
struct mapped_device *md;
- /*
- * Sanity checks.
- */
- BUG_ON(!clone->bi_size);
-
clone->bi_end_io = clone_endio;
clone->bi_private = tio;
@@ -752,6 +1055,48 @@ static struct bio *clone_bio(struct bio *bio, sector_t sector,
return clone;
}
+static struct dm_target_io *alloc_tio(struct clone_info *ci,
+ struct dm_target *ti)
+{
+ struct dm_target_io *tio = mempool_alloc(ci->md->tio_pool, GFP_NOIO);
+
+ tio->io = ci->io;
+ tio->ti = ti;
+ memset(&tio->info, 0, sizeof(tio->info));
+
+ return tio;
+}
+
+static void __flush_target(struct clone_info *ci, struct dm_target *ti,
+ unsigned flush_nr)
+{
+ struct dm_target_io *tio = alloc_tio(ci, ti);
+ struct bio *clone;
+
+ tio->info.flush_request = flush_nr;
+
+ clone = bio_alloc_bioset(GFP_NOIO, 0, ci->md->bs);
+ __bio_clone(clone, ci->bio);
+ clone->bi_destructor = dm_bio_destructor;
+
+ __map_bio(ti, clone, tio);
+}
+
+static int __clone_and_map_empty_barrier(struct clone_info *ci)
+{
+ unsigned target_nr = 0, flush_nr;
+ struct dm_target *ti;
+
+ while ((ti = dm_table_get_target(ci->map, target_nr++)))
+ for (flush_nr = 0; flush_nr < ti->num_flush_requests;
+ flush_nr++)
+ __flush_target(ci, ti, flush_nr);
+
+ ci->sector_count = 0;
+
+ return 0;
+}
+
static int __clone_and_map(struct clone_info *ci)
{
struct bio *clone, *bio = ci->bio;
@@ -759,6 +1104,9 @@ static int __clone_and_map(struct clone_info *ci)
sector_t len = 0, max;
struct dm_target_io *tio;
+ if (unlikely(bio_empty_barrier(bio)))
+ return __clone_and_map_empty_barrier(ci);
+
ti = dm_table_find_target(ci->map, ci->sector);
if (!dm_target_is_valid(ti))
return -EIO;
@@ -768,10 +1116,7 @@ static int __clone_and_map(struct clone_info *ci)
/*
* Allocate a target io object.
*/
- tio = alloc_tio(ci->md);
- tio->io = ci->io;
- tio->ti = ti;
- memset(&tio->info, 0, sizeof(tio->info));
+ tio = alloc_tio(ci, ti);
if (ci->sector_count <= max) {
/*
@@ -827,10 +1172,7 @@ static int __clone_and_map(struct clone_info *ci)
max = max_io_len(ci->md, ci->sector, ti);
- tio = alloc_tio(ci->md);
- tio->io = ci->io;
- tio->ti = ti;
- memset(&tio->info, 0, sizeof(tio->info));
+ tio = alloc_tio(ci, ti);
}
len = min(remaining, max);
@@ -865,7 +1207,8 @@ static void __split_and_process_bio(struct mapped_device *md, struct bio *bio)
if (!bio_barrier(bio))
bio_io_error(bio);
else
- md->barrier_error = -EIO;
+ if (!md->barrier_error)
+ md->barrier_error = -EIO;
return;
}
@@ -878,6 +1221,8 @@ static void __split_and_process_bio(struct mapped_device *md, struct bio *bio)
ci.io->md = md;
ci.sector = bio->bi_sector;
ci.sector_count = bio_sectors(bio);
+ if (unlikely(bio_empty_barrier(bio)))
+ ci.sector_count = 1;
ci.idx = bio->bi_idx;
start_io_acct(ci.io);
@@ -925,6 +1270,16 @@ static int dm_merge_bvec(struct request_queue *q,
*/
if (max_size && ti->type->merge)
max_size = ti->type->merge(ti, bvm, biovec, max_size);
+ /*
+ * If the target doesn't support merge method and some of the devices
+ * provided their merge_bvec method (we know this by looking at
+ * queue_max_hw_sectors), then we can't allow bios with multiple vector
+ * entries. So always set max_size to 0, and the code below allows
+ * just one page.
+ */
+ else if (queue_max_hw_sectors(q) <= PAGE_SIZE >> 9)
+
+ max_size = 0;
out_table:
dm_table_put(map);
@@ -943,7 +1298,7 @@ out:
* The request function that just remaps the bio built up by
* dm_merge_bvec.
*/
-static int dm_request(struct request_queue *q, struct bio *bio)
+static int _dm_request(struct request_queue *q, struct bio *bio)
{
int rw = bio_data_dir(bio);
struct mapped_device *md = q->queuedata;
@@ -980,12 +1335,274 @@ static int dm_request(struct request_queue *q, struct bio *bio)
return 0;
}
+static int dm_make_request(struct request_queue *q, struct bio *bio)
+{
+ struct mapped_device *md = q->queuedata;
+
+ if (unlikely(bio_barrier(bio))) {
+ bio_endio(bio, -EOPNOTSUPP);
+ return 0;
+ }
+
+ return md->saved_make_request_fn(q, bio); /* call __make_request() */
+}
+
+static int dm_request_based(struct mapped_device *md)
+{
+ return blk_queue_stackable(md->queue);
+}
+
+static int dm_request(struct request_queue *q, struct bio *bio)
+{
+ struct mapped_device *md = q->queuedata;
+
+ if (dm_request_based(md))
+ return dm_make_request(q, bio);
+
+ return _dm_request(q, bio);
+}
+
+void dm_dispatch_request(struct request *rq)
+{
+ int r;
+
+ if (blk_queue_io_stat(rq->q))
+ rq->cmd_flags |= REQ_IO_STAT;
+
+ rq->start_time = jiffies;
+ r = blk_insert_cloned_request(rq->q, rq);
+ if (r)
+ dm_complete_request(rq, r);
+}
+EXPORT_SYMBOL_GPL(dm_dispatch_request);
+
+static void dm_rq_bio_destructor(struct bio *bio)
+{
+ struct dm_rq_clone_bio_info *info = bio->bi_private;
+ struct mapped_device *md = info->tio->md;
+
+ free_bio_info(info);
+ bio_free(bio, md->bs);
+}
+
+static int dm_rq_bio_constructor(struct bio *bio, struct bio *bio_orig,
+ void *data)
+{
+ struct dm_rq_target_io *tio = data;
+ struct mapped_device *md = tio->md;
+ struct dm_rq_clone_bio_info *info = alloc_bio_info(md);
+
+ if (!info)
+ return -ENOMEM;
+
+ info->orig = bio_orig;
+ info->tio = tio;
+ bio->bi_end_io = end_clone_bio;
+ bio->bi_private = info;
+ bio->bi_destructor = dm_rq_bio_destructor;
+
+ return 0;
+}
+
+static int setup_clone(struct request *clone, struct request *rq,
+ struct dm_rq_target_io *tio)
+{
+ int r = blk_rq_prep_clone(clone, rq, tio->md->bs, GFP_ATOMIC,
+ dm_rq_bio_constructor, tio);
+
+ if (r)
+ return r;
+
+ clone->cmd = rq->cmd;
+ clone->cmd_len = rq->cmd_len;
+ clone->sense = rq->sense;
+ clone->buffer = rq->buffer;
+ clone->end_io = end_clone_request;
+ clone->end_io_data = tio;
+
+ return 0;
+}
+
+static int dm_rq_flush_suspending(struct mapped_device *md)
+{
+ return !md->suspend_rq.special;
+}
+
+/*
+ * Called with the queue lock held.
+ */
+static int dm_prep_fn(struct request_queue *q, struct request *rq)
+{
+ struct mapped_device *md = q->queuedata;
+ struct dm_rq_target_io *tio;
+ struct request *clone;
+
+ if (unlikely(rq == &md->suspend_rq)) {
+ if (dm_rq_flush_suspending(md))
+ return BLKPREP_OK;
+ else
+ /* The flush suspend was interrupted */
+ return BLKPREP_KILL;
+ }
+
+ if (unlikely(rq->special)) {
+ DMWARN("Already has something in rq->special.");
+ return BLKPREP_KILL;
+ }
+
+ tio = alloc_rq_tio(md); /* Only one for each original request */
+ if (!tio)
+ /* -ENOMEM */
+ return BLKPREP_DEFER;
+
+ tio->md = md;
+ tio->ti = NULL;
+ tio->orig = rq;
+ tio->error = 0;
+ memset(&tio->info, 0, sizeof(tio->info));
+
+ clone = &tio->clone;
+ if (setup_clone(clone, rq, tio)) {
+ /* -ENOMEM */
+ free_rq_tio(tio);
+ return BLKPREP_DEFER;
+ }
+
+ rq->special = clone;
+ rq->cmd_flags |= REQ_DONTPREP;
+
+ return BLKPREP_OK;
+}
+
+static void map_request(struct dm_target *ti, struct request *rq,
+ struct mapped_device *md)
+{
+ int r;
+ struct request *clone = rq->special;
+ struct dm_rq_target_io *tio = clone->end_io_data;
+
+ /*
+ * Hold the md reference here for the in-flight I/O.
+ * We can't rely on the reference count by device opener,
+ * because the device may be closed during the request completion
+ * when all bios are completed.
+ * See the comment in rq_completed() too.
+ */
+ dm_get(md);
+
+ tio->ti = ti;
+ r = ti->type->map_rq(ti, clone, &tio->info);
+ switch (r) {
+ case DM_MAPIO_SUBMITTED:
+ /* The target has taken the I/O to submit by itself later */
+ break;
+ case DM_MAPIO_REMAPPED:
+ /* The target has remapped the I/O so dispatch it */
+ dm_dispatch_request(clone);
+ break;
+ case DM_MAPIO_REQUEUE:
+ /* The target wants to requeue the I/O */
+ dm_requeue_unmapped_request(clone);
+ break;
+ default:
+ if (r > 0) {
+ DMWARN("unimplemented target map return value: %d", r);
+ BUG();
+ }
+
+ /* The target wants to complete the I/O */
+ dm_kill_unmapped_request(clone, r);
+ break;
+ }
+}
+
+/*
+ * q->request_fn for request-based dm.
+ * Called with the queue lock held.
+ */
+static void dm_request_fn(struct request_queue *q)
+{
+ struct mapped_device *md = q->queuedata;
+ struct dm_table *map = dm_get_table(md);
+ struct dm_target *ti;
+ struct request *rq;
+
+ /*
+ * For noflush suspend, check blk_queue_stopped() to immediately
+ * quit I/O dispatching.
+ */
+ while (!blk_queue_plugged(q) && !blk_queue_stopped(q)) {
+ rq = blk_peek_request(q);
+ if (!rq)
+ goto plug_and_out;
+
+ if (unlikely(rq == &md->suspend_rq)) { /* Flush suspend maker */
+ if (queue_in_flight(q))
+ /* Not quiet yet. Wait more */
+ goto plug_and_out;
+
+ /* This device should be quiet now */
+ __stop_queue(q);
+ blk_start_request(rq);
+ __blk_end_request_all(rq, 0);
+ wake_up(&md->wait);
+ goto out;
+ }
+
+ ti = dm_table_find_target(map, blk_rq_pos(rq));
+ if (ti->type->busy && ti->type->busy(ti))
+ goto plug_and_out;
+
+ blk_start_request(rq);
+ spin_unlock(q->queue_lock);
+ map_request(ti, rq, md);
+ spin_lock_irq(q->queue_lock);
+ }
+
+ goto out;
+
+plug_and_out:
+ if (!elv_queue_empty(q))
+ /* Some requests still remain, retry later */
+ blk_plug_device(q);
+
+out:
+ dm_table_put(map);
+
+ return;
+}
+
+int dm_underlying_device_busy(struct request_queue *q)
+{
+ return blk_lld_busy(q);
+}
+EXPORT_SYMBOL_GPL(dm_underlying_device_busy);
+
+static int dm_lld_busy(struct request_queue *q)
+{
+ int r;
+ struct mapped_device *md = q->queuedata;
+ struct dm_table *map = dm_get_table(md);
+
+ if (!map || test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags))
+ r = 1;
+ else
+ r = dm_table_any_busy_target(map);
+
+ dm_table_put(map);
+
+ return r;
+}
+
static void dm_unplug_all(struct request_queue *q)
{
struct mapped_device *md = q->queuedata;
struct dm_table *map = dm_get_table(md);
if (map) {
+ if (dm_request_based(md))
+ generic_unplug_device(q);
+
dm_table_unplug_all(map);
dm_table_put(map);
}
@@ -1000,7 +1617,16 @@ static int dm_any_congested(void *congested_data, int bdi_bits)
if (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) {
map = dm_get_table(md);
if (map) {
- r = dm_table_any_congested(map, bdi_bits);
+ /*
+ * Request-based dm cares about only own queue for
+ * the query about congestion status of request_queue
+ */
+ if (dm_request_based(md))
+ r = md->queue->backing_dev_info.state &
+ bdi_bits;
+ else
+ r = dm_table_any_congested(map, bdi_bits);
+
dm_table_put(map);
}
}
@@ -1123,30 +1749,32 @@ static struct mapped_device *alloc_dev(int minor)
INIT_LIST_HEAD(&md->uevent_list);
spin_lock_init(&md->uevent_lock);
- md->queue = blk_alloc_queue(GFP_KERNEL);
+ md->queue = blk_init_queue(dm_request_fn, NULL);
if (!md->queue)
goto bad_queue;
+ /*
+ * Request-based dm devices cannot be stacked on top of bio-based dm
+ * devices. The type of this dm device has not been decided yet,
+ * although we initialized the queue using blk_init_queue().
+ * The type is decided at the first table loading time.
+ * To prevent problematic device stacking, clear the queue flag
+ * for request stacking support until then.
+ *
+ * This queue is new, so no concurrency on the queue_flags.
+ */
+ queue_flag_clear_unlocked(QUEUE_FLAG_STACKABLE, md->queue);
+ md->saved_make_request_fn = md->queue->make_request_fn;
md->queue->queuedata = md;
md->queue->backing_dev_info.congested_fn = dm_any_congested;
md->queue->backing_dev_info.congested_data = md;
blk_queue_make_request(md->queue, dm_request);
- blk_queue_ordered(md->queue, QUEUE_ORDERED_DRAIN, NULL);
blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY);
md->queue->unplug_fn = dm_unplug_all;
blk_queue_merge_bvec(md->queue, dm_merge_bvec);
-
- md->io_pool = mempool_create_slab_pool(MIN_IOS, _io_cache);
- if (!md->io_pool)
- goto bad_io_pool;
-
- md->tio_pool = mempool_create_slab_pool(MIN_IOS, _tio_cache);
- if (!md->tio_pool)
- goto bad_tio_pool;
-
- md->bs = bioset_create(16, 0);
- if (!md->bs)
- goto bad_no_bioset;
+ blk_queue_softirq_done(md->queue, dm_softirq_done);
+ blk_queue_prep_rq(md->queue, dm_prep_fn);
+ blk_queue_lld_busy(md->queue, dm_lld_busy);
md->disk = alloc_disk(1);
if (!md->disk)
@@ -1170,6 +1798,10 @@ static struct mapped_device *alloc_dev(int minor)
if (!md->wq)
goto bad_thread;
+ md->bdev = bdget_disk(md->disk, 0);
+ if (!md->bdev)
+ goto bad_bdev;
+
/* Populate the mapping, nobody knows we exist yet */
spin_lock(&_minor_lock);
old_md = idr_replace(&_minor_idr, md, minor);
@@ -1179,15 +1811,11 @@ static struct mapped_device *alloc_dev(int minor)
return md;
+bad_bdev:
+ destroy_workqueue(md->wq);
bad_thread:
put_disk(md->disk);
bad_disk:
- bioset_free(md->bs);
-bad_no_bioset:
- mempool_destroy(md->tio_pool);
-bad_tio_pool:
- mempool_destroy(md->io_pool);
-bad_io_pool:
blk_cleanup_queue(md->queue);
bad_queue:
free_minor(minor);
@@ -1204,14 +1832,15 @@ static void free_dev(struct mapped_device *md)
{
int minor = MINOR(disk_devt(md->disk));
- if (md->suspended_bdev) {
- unlock_fs(md);
- bdput(md->suspended_bdev);
- }
+ unlock_fs(md);
+ bdput(md->bdev);
destroy_workqueue(md->wq);
- mempool_destroy(md->tio_pool);
- mempool_destroy(md->io_pool);
- bioset_free(md->bs);
+ if (md->tio_pool)
+ mempool_destroy(md->tio_pool);
+ if (md->io_pool)
+ mempool_destroy(md->io_pool);
+ if (md->bs)
+ bioset_free(md->bs);
blk_integrity_unregister(md->disk);
del_gendisk(md->disk);
free_minor(minor);
@@ -1226,6 +1855,29 @@ static void free_dev(struct mapped_device *md)
kfree(md);
}
+static void __bind_mempools(struct mapped_device *md, struct dm_table *t)
+{
+ struct dm_md_mempools *p;
+
+ if (md->io_pool && md->tio_pool && md->bs)
+ /* the md already has necessary mempools */
+ goto out;
+
+ p = dm_table_get_md_mempools(t);
+ BUG_ON(!p || md->io_pool || md->tio_pool || md->bs);
+
+ md->io_pool = p->io_pool;
+ p->io_pool = NULL;
+ md->tio_pool = p->tio_pool;
+ p->tio_pool = NULL;
+ md->bs = p->bs;
+ p->bs = NULL;
+
+out:
+ /* mempool bind completed, now no need any mempools in the table */
+ dm_table_free_md_mempools(t);
+}
+
/*
* Bind a table to the device.
*/
@@ -1249,15 +1901,17 @@ static void __set_size(struct mapped_device *md, sector_t size)
{
set_capacity(md->disk, size);
- mutex_lock(&md->suspended_bdev->bd_inode->i_mutex);
- i_size_write(md->suspended_bdev->bd_inode, (loff_t)size << SECTOR_SHIFT);
- mutex_unlock(&md->suspended_bdev->bd_inode->i_mutex);
+ mutex_lock(&md->bdev->bd_inode->i_mutex);
+ i_size_write(md->bdev->bd_inode, (loff_t)size << SECTOR_SHIFT);
+ mutex_unlock(&md->bdev->bd_inode->i_mutex);
}
-static int __bind(struct mapped_device *md, struct dm_table *t)
+static int __bind(struct mapped_device *md, struct dm_table *t,
+ struct queue_limits *limits)
{
struct request_queue *q = md->queue;
sector_t size;
+ unsigned long flags;
size = dm_table_get_size(t);
@@ -1267,8 +1921,7 @@ static int __bind(struct mapped_device *md, struct dm_table *t)
if (size != get_capacity(md->disk))
memset(&md->geometry, 0, sizeof(md->geometry));
- if (md->suspended_bdev)
- __set_size(md, size);
+ __set_size(md, size);
if (!size) {
dm_table_destroy(t);
@@ -1277,10 +1930,22 @@ static int __bind(struct mapped_device *md, struct dm_table *t)
dm_table_event_callback(t, event_callback, md);
- write_lock(&md->map_lock);
+ /*
+ * The queue hasn't been stopped yet, if the old table type wasn't
+ * for request-based during suspension. So stop it to prevent
+ * I/O mapping before resume.
+ * This must be done before setting the queue restrictions,
+ * because request-based dm may be run just after the setting.
+ */
+ if (dm_table_request_based(t) && !blk_queue_stopped(q))
+ stop_queue(q);
+
+ __bind_mempools(md, t);
+
+ write_lock_irqsave(&md->map_lock, flags);
md->map = t;
- dm_table_set_restrictions(t, q);
- write_unlock(&md->map_lock);
+ dm_table_set_restrictions(t, q, limits);
+ write_unlock_irqrestore(&md->map_lock, flags);
return 0;
}
@@ -1288,14 +1953,15 @@ static int __bind(struct mapped_device *md, struct dm_table *t)
static void __unbind(struct mapped_device *md)
{
struct dm_table *map = md->map;
+ unsigned long flags;
if (!map)
return;
dm_table_event_callback(map, NULL, NULL);
- write_lock(&md->map_lock);
+ write_lock_irqsave(&md->map_lock, flags);
md->map = NULL;
- write_unlock(&md->map_lock);
+ write_unlock_irqrestore(&md->map_lock, flags);
dm_table_destroy(map);
}
@@ -1399,6 +2065,8 @@ static int dm_wait_for_completion(struct mapped_device *md, int interruptible)
{
int r = 0;
DECLARE_WAITQUEUE(wait, current);
+ struct request_queue *q = md->queue;
+ unsigned long flags;
dm_unplug_all(md->queue);
@@ -1408,7 +2076,14 @@ static int dm_wait_for_completion(struct mapped_device *md, int interruptible)
set_current_state(interruptible);
smp_mb();
- if (!atomic_read(&md->pending))
+ if (dm_request_based(md)) {
+ spin_lock_irqsave(q->queue_lock, flags);
+ if (!queue_in_flight(q) && blk_queue_stopped(q)) {
+ spin_unlock_irqrestore(q->queue_lock, flags);
+ break;
+ }
+ spin_unlock_irqrestore(q->queue_lock, flags);
+ } else if (!atomic_read(&md->pending))
break;
if (interruptible == TASK_INTERRUPTIBLE &&
@@ -1426,34 +2101,36 @@ static int dm_wait_for_completion(struct mapped_device *md, int interruptible)
return r;
}
-static int dm_flush(struct mapped_device *md)
+static void dm_flush(struct mapped_device *md)
{
dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE);
- return 0;
+
+ bio_init(&md->barrier_bio);
+ md->barrier_bio.bi_bdev = md->bdev;
+ md->barrier_bio.bi_rw = WRITE_BARRIER;
+ __split_and_process_bio(md, &md->barrier_bio);
+
+ dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE);
}
static void process_barrier(struct mapped_device *md, struct bio *bio)
{
- int error = dm_flush(md);
-
- if (unlikely(error)) {
- bio_endio(bio, error);
- return;
- }
- if (bio_empty_barrier(bio)) {
- bio_endio(bio, 0);
- return;
- }
-
- __split_and_process_bio(md, bio);
+ md->barrier_error = 0;
- error = dm_flush(md);
+ dm_flush(md);
- if (!error && md->barrier_error)
- error = md->barrier_error;
+ if (!bio_empty_barrier(bio)) {
+ __split_and_process_bio(md, bio);
+ dm_flush(md);
+ }
if (md->barrier_error != DM_ENDIO_REQUEUE)
- bio_endio(bio, error);
+ bio_endio(bio, md->barrier_error);
+ else {
+ spin_lock_irq(&md->deferred_lock);
+ bio_list_add_head(&md->deferred, bio);
+ spin_unlock_irq(&md->deferred_lock);
+ }
}
/*
@@ -1479,10 +2156,14 @@ static void dm_wq_work(struct work_struct *work)
up_write(&md->io_lock);
- if (bio_barrier(c))
- process_barrier(md, c);
- else
- __split_and_process_bio(md, c);
+ if (dm_request_based(md))
+ generic_make_request(c);
+ else {
+ if (bio_barrier(c))
+ process_barrier(md, c);
+ else
+ __split_and_process_bio(md, c);
+ }
down_write(&md->io_lock);
}
@@ -1502,6 +2183,7 @@ static void dm_queue_flush(struct mapped_device *md)
*/
int dm_swap_table(struct mapped_device *md, struct dm_table *table)
{
+ struct queue_limits limits;
int r = -EINVAL;
mutex_lock(&md->suspend_lock);
@@ -1510,19 +2192,96 @@ int dm_swap_table(struct mapped_device *md, struct dm_table *table)
if (!dm_suspended(md))
goto out;
- /* without bdev, the device size cannot be changed */
- if (!md->suspended_bdev)
- if (get_capacity(md->disk) != dm_table_get_size(table))
- goto out;
+ r = dm_calculate_queue_limits(table, &limits);
+ if (r)
+ goto out;
+
+ /* cannot change the device type, once a table is bound */
+ if (md->map &&
+ (dm_table_get_type(md->map) != dm_table_get_type(table))) {
+ DMWARN("can't change the device type after a table is bound");
+ goto out;
+ }
+
+ /*
+ * It is enought that blk_queue_ordered() is called only once when
+ * the first bio-based table is bound.
+ *
+ * This setting should be moved to alloc_dev() when request-based dm
+ * supports barrier.
+ */
+ if (!md->map && dm_table_bio_based(table))
+ blk_queue_ordered(md->queue, QUEUE_ORDERED_DRAIN, NULL);
__unbind(md);
- r = __bind(md, table);
+ r = __bind(md, table, &limits);
out:
mutex_unlock(&md->suspend_lock);
return r;
}
+static void dm_rq_invalidate_suspend_marker(struct mapped_device *md)
+{
+ md->suspend_rq.special = (void *)0x1;
+}
+
+static void dm_rq_abort_suspend(struct mapped_device *md, int noflush)
+{
+ struct request_queue *q = md->queue;
+ unsigned long flags;
+
+ spin_lock_irqsave(q->queue_lock, flags);
+ if (!noflush)
+ dm_rq_invalidate_suspend_marker(md);
+ __start_queue(q);
+ spin_unlock_irqrestore(q->queue_lock, flags);
+}
+
+static void dm_rq_start_suspend(struct mapped_device *md, int noflush)
+{
+ struct request *rq = &md->suspend_rq;
+ struct request_queue *q = md->queue;
+
+ if (noflush)
+ stop_queue(q);
+ else {
+ blk_rq_init(q, rq);
+ blk_insert_request(q, rq, 0, NULL);
+ }
+}
+
+static int dm_rq_suspend_available(struct mapped_device *md, int noflush)
+{
+ int r = 1;
+ struct request *rq = &md->suspend_rq;
+ struct request_queue *q = md->queue;
+ unsigned long flags;
+
+ if (noflush)
+ return r;
+
+ /* The marker must be protected by queue lock if it is in use */
+ spin_lock_irqsave(q->queue_lock, flags);
+ if (unlikely(rq->ref_count)) {
+ /*
+ * This can happen, when the previous flush suspend was
+ * interrupted, the marker is still in the queue and
+ * this flush suspend has been invoked, because we don't
+ * remove the marker at the time of suspend interruption.
+ * We have only one marker per mapped_device, so we can't
+ * start another flush suspend while it is in use.
+ */
+ BUG_ON(!rq->special); /* The marker should be invalidated */
+ DMWARN("Invalidating the previous flush suspend is still in"
+ " progress. Please retry later.");
+ r = 0;
+ }
+ spin_unlock_irqrestore(q->queue_lock, flags);
+
+ return r;
+}
+
/*
* Functions to lock and unlock any filesystem running on the
* device.
@@ -1533,7 +2292,7 @@ static int lock_fs(struct mapped_device *md)
WARN_ON(md->frozen_sb);
- md->frozen_sb = freeze_bdev(md->suspended_bdev);
+ md->frozen_sb = freeze_bdev(md->bdev);
if (IS_ERR(md->frozen_sb)) {
r = PTR_ERR(md->frozen_sb);
md->frozen_sb = NULL;
@@ -1542,9 +2301,6 @@ static int lock_fs(struct mapped_device *md)
set_bit(DMF_FROZEN, &md->flags);
- /* don't bdput right now, we don't want the bdev
- * to go away while it is locked.
- */
return 0;
}
@@ -1553,7 +2309,7 @@ static void unlock_fs(struct mapped_device *md)
if (!test_bit(DMF_FROZEN, &md->flags))
return;
- thaw_bdev(md->suspended_bdev, md->frozen_sb);
+ thaw_bdev(md->bdev, md->frozen_sb);
md->frozen_sb = NULL;
clear_bit(DMF_FROZEN, &md->flags);
}
@@ -1565,6 +2321,53 @@ static void unlock_fs(struct mapped_device *md)
* dm_bind_table, dm_suspend must be called to flush any in
* flight bios and ensure that any further io gets deferred.
*/
+/*
+ * Suspend mechanism in request-based dm.
+ *
+ * After the suspend starts, further incoming requests are kept in
+ * the request_queue and deferred.
+ * Remaining requests in the request_queue at the start of suspend are flushed
+ * if it is flush suspend.
+ * The suspend completes when the following conditions have been satisfied,
+ * so wait for it:
+ * 1. q->in_flight is 0 (which means no in_flight request)
+ * 2. queue has been stopped (which means no request dispatching)
+ *
+ *
+ * Noflush suspend
+ * ---------------
+ * Noflush suspend doesn't need to dispatch remaining requests.
+ * So stop the queue immediately. Then, wait for all in_flight requests
+ * to be completed or requeued.
+ *
+ * To abort noflush suspend, start the queue.
+ *
+ *
+ * Flush suspend
+ * -------------
+ * Flush suspend needs to dispatch remaining requests. So stop the queue
+ * after the remaining requests are completed. (Requeued request must be also
+ * re-dispatched and completed. Until then, we can't stop the queue.)
+ *
+ * During flushing the remaining requests, further incoming requests are also
+ * inserted to the same queue. To distinguish which requests are to be
+ * flushed, we insert a marker request to the queue at the time of starting
+ * flush suspend, like a barrier.
+ * The dispatching is blocked when the marker is found on the top of the queue.
+ * And the queue is stopped when all in_flight requests are completed, since
+ * that means the remaining requests are completely flushed.
+ * Then, the marker is removed from the queue.
+ *
+ * To abort flush suspend, we also need to take care of the marker, not only
+ * starting the queue.
+ * We don't remove the marker forcibly from the queue since it's against
+ * the block-layer manner. Instead, we put a invalidated mark on the marker.
+ * When the invalidated marker is found on the top of the queue, it is
+ * immediately removed from the queue, so it doesn't block dispatching.
+ * Because we have only one marker per mapped_device, we can't start another
+ * flush suspend until the invalidated marker is removed from the queue.
+ * So fail and return with -EBUSY in such a case.
+ */
int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
{
struct dm_table *map = NULL;
@@ -1579,6 +2382,11 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
goto out_unlock;
}
+ if (dm_request_based(md) && !dm_rq_suspend_available(md, noflush)) {
+ r = -EBUSY;
+ goto out_unlock;
+ }
+
map = dm_get_table(md);
/*
@@ -1591,24 +2399,14 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
/* This does not get reverted if there's an error later. */
dm_table_presuspend_targets(map);
- /* bdget() can stall if the pending I/Os are not flushed */
- if (!noflush) {
- md->suspended_bdev = bdget_disk(md->disk, 0);
- if (!md->suspended_bdev) {
- DMWARN("bdget failed in dm_suspend");
- r = -ENOMEM;
+ /*
+ * Flush I/O to the device. noflush supersedes do_lockfs,
+ * because lock_fs() needs to flush I/Os.
+ */
+ if (!noflush && do_lockfs) {
+ r = lock_fs(md);
+ if (r)
goto out;
- }
-
- /*
- * Flush I/O to the device. noflush supersedes do_lockfs,
- * because lock_fs() needs to flush I/Os.
- */
- if (do_lockfs) {
- r = lock_fs(md);
- if (r)
- goto out;
- }
}
/*
@@ -1634,6 +2432,9 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
flush_workqueue(md->wq);
+ if (dm_request_based(md))
+ dm_rq_start_suspend(md, noflush);
+
/*
* At this point no more requests are entering target request routines.
* We call dm_wait_for_completion to wait for all existing requests
@@ -1650,6 +2451,9 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
if (r < 0) {
dm_queue_flush(md);
+ if (dm_request_based(md))
+ dm_rq_abort_suspend(md, noflush);
+
unlock_fs(md);
goto out; /* pushback list is already flushed, so skip flush */
}
@@ -1665,11 +2469,6 @@ int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
set_bit(DMF_SUSPENDED, &md->flags);
out:
- if (r && md->suspended_bdev) {
- bdput(md->suspended_bdev);
- md->suspended_bdev = NULL;
- }
-
dm_table_put(map);
out_unlock:
@@ -1696,21 +2495,20 @@ int dm_resume(struct mapped_device *md)
dm_queue_flush(md);
- unlock_fs(md);
+ /*
+ * Flushing deferred I/Os must be done after targets are resumed
+ * so that mapping of targets can work correctly.
+ * Request-based dm is queueing the deferred I/Os in its request_queue.
+ */
+ if (dm_request_based(md))
+ start_queue(md->queue);
- if (md->suspended_bdev) {
- bdput(md->suspended_bdev);
- md->suspended_bdev = NULL;
- }
+ unlock_fs(md);
clear_bit(DMF_SUSPENDED, &md->flags);
dm_table_unplug_all(map);
-
- dm_kobject_uevent(md);
-
r = 0;
-
out:
dm_table_put(map);
mutex_unlock(&md->suspend_lock);
@@ -1721,9 +2519,19 @@ out:
/*-----------------------------------------------------------------
* Event notification.
*---------------------------------------------------------------*/
-void dm_kobject_uevent(struct mapped_device *md)
-{
- kobject_uevent(&disk_to_dev(md->disk)->kobj, KOBJ_CHANGE);
+void dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
+ unsigned cookie)
+{
+ char udev_cookie[DM_COOKIE_LENGTH];
+ char *envp[] = { udev_cookie, NULL };
+
+ if (!cookie)
+ kobject_uevent(&disk_to_dev(md->disk)->kobj, action);
+ else {
+ snprintf(udev_cookie, DM_COOKIE_LENGTH, "%s=%u",
+ DM_COOKIE_ENV_VAR_NAME, cookie);
+ kobject_uevent_env(&disk_to_dev(md->disk)->kobj, action, envp);
+ }
}
uint32_t dm_next_uevent_seq(struct mapped_device *md)
@@ -1777,6 +2585,10 @@ struct mapped_device *dm_get_from_kobject(struct kobject *kobj)
if (&md->kobj != kobj)
return NULL;
+ if (test_bit(DMF_FREEING, &md->flags) ||
+ test_bit(DMF_DELETING, &md->flags))
+ return NULL;
+
dm_get(md);
return md;
}
@@ -1797,6 +2609,61 @@ int dm_noflush_suspending(struct dm_target *ti)
}
EXPORT_SYMBOL_GPL(dm_noflush_suspending);
+struct dm_md_mempools *dm_alloc_md_mempools(unsigned type)
+{
+ struct dm_md_mempools *pools = kmalloc(sizeof(*pools), GFP_KERNEL);
+
+ if (!pools)
+ return NULL;
+
+ pools->io_pool = (type == DM_TYPE_BIO_BASED) ?
+ mempool_create_slab_pool(MIN_IOS, _io_cache) :
+ mempool_create_slab_pool(MIN_IOS, _rq_bio_info_cache);
+ if (!pools->io_pool)
+ goto free_pools_and_out;
+
+ pools->tio_pool = (type == DM_TYPE_BIO_BASED) ?
+ mempool_create_slab_pool(MIN_IOS, _tio_cache) :
+ mempool_create_slab_pool(MIN_IOS, _rq_tio_cache);
+ if (!pools->tio_pool)
+ goto free_io_pool_and_out;
+
+ pools->bs = (type == DM_TYPE_BIO_BASED) ?
+ bioset_create(16, 0) : bioset_create(MIN_IOS, 0);
+ if (!pools->bs)
+ goto free_tio_pool_and_out;
+
+ return pools;
+
+free_tio_pool_and_out:
+ mempool_destroy(pools->tio_pool);
+
+free_io_pool_and_out:
+ mempool_destroy(pools->io_pool);
+
+free_pools_and_out:
+ kfree(pools);
+
+ return NULL;
+}
+
+void dm_free_md_mempools(struct dm_md_mempools *pools)
+{
+ if (!pools)
+ return;
+
+ if (pools->io_pool)
+ mempool_destroy(pools->io_pool);
+
+ if (pools->tio_pool)
+ mempool_destroy(pools->tio_pool);
+
+ if (pools->bs)
+ bioset_free(pools->bs);
+
+ kfree(pools);
+}
+
static struct block_device_operations dm_blk_dops = {
.open = dm_blk_open,
.release = dm_blk_close,
diff --git a/drivers/md/dm.h b/drivers/md/dm.h
index a31506d93e91..23278ae80f08 100644
--- a/drivers/md/dm.h
+++ b/drivers/md/dm.h
@@ -23,6 +23,13 @@
#define DM_SUSPEND_NOFLUSH_FLAG (1 << 1)
/*
+ * Type of table and mapped_device's mempool
+ */
+#define DM_TYPE_NONE 0
+#define DM_TYPE_BIO_BASED 1
+#define DM_TYPE_REQUEST_BASED 2
+
+/*
* List of devices that a metadevice uses and should open/close.
*/
struct dm_dev_internal {
@@ -32,6 +39,7 @@ struct dm_dev_internal {
};
struct dm_table;
+struct dm_md_mempools;
/*-----------------------------------------------------------------
* Internal table functions.
@@ -41,18 +49,34 @@ void dm_table_event_callback(struct dm_table *t,
void (*fn)(void *), void *context);
struct dm_target *dm_table_get_target(struct dm_table *t, unsigned int index);
struct dm_target *dm_table_find_target(struct dm_table *t, sector_t sector);
-void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q);
+int dm_calculate_queue_limits(struct dm_table *table,
+ struct queue_limits *limits);
+void dm_table_set_restrictions(struct dm_table *t, struct request_queue *q,
+ struct queue_limits *limits);
struct list_head *dm_table_get_devices(struct dm_table *t);
void dm_table_presuspend_targets(struct dm_table *t);
void dm_table_postsuspend_targets(struct dm_table *t);
int dm_table_resume_targets(struct dm_table *t);
int dm_table_any_congested(struct dm_table *t, int bdi_bits);
+int dm_table_any_busy_target(struct dm_table *t);
+int dm_table_set_type(struct dm_table *t);
+unsigned dm_table_get_type(struct dm_table *t);
+bool dm_table_bio_based(struct dm_table *t);
+bool dm_table_request_based(struct dm_table *t);
+int dm_table_alloc_md_mempools(struct dm_table *t);
+void dm_table_free_md_mempools(struct dm_table *t);
+struct dm_md_mempools *dm_table_get_md_mempools(struct dm_table *t);
/*
* To check the return value from dm_table_find_target().
*/
#define dm_target_is_valid(t) ((t)->table)
+/*
+ * To check whether the target type is request-based or not (bio-based).
+ */
+#define dm_target_request_based(t) ((t)->type->map_rq != NULL)
+
/*-----------------------------------------------------------------
* A registry of target types.
*---------------------------------------------------------------*/
@@ -92,9 +116,16 @@ void dm_stripe_exit(void);
int dm_open_count(struct mapped_device *md);
int dm_lock_for_deletion(struct mapped_device *md);
-void dm_kobject_uevent(struct mapped_device *md);
+void dm_kobject_uevent(struct mapped_device *md, enum kobject_action action,
+ unsigned cookie);
int dm_kcopyd_init(void);
void dm_kcopyd_exit(void);
+/*
+ * Mempool operations
+ */
+struct dm_md_mempools *dm_alloc_md_mempools(unsigned type);
+void dm_free_md_mempools(struct dm_md_mempools *pools);
+
#endif
diff --git a/include/linux/Kbuild b/include/linux/Kbuild
index 03f22076381f..334a3593cdfd 100644
--- a/include/linux/Kbuild
+++ b/include/linux/Kbuild
@@ -57,6 +57,7 @@ header-y += dlmconstants.h
header-y += dlm_device.h
header-y += dlm_netlink.h
header-y += dm-ioctl.h
+header-y += dm-log-userspace.h
header-y += dn.h
header-y += dqblk_xfs.h
header-y += efs_fs_sb.h
diff --git a/include/linux/connector.h b/include/linux/connector.h
index b9966e64604e..b68d27850d51 100644
--- a/include/linux/connector.h
+++ b/include/linux/connector.h
@@ -41,8 +41,10 @@
#define CN_IDX_BB 0x5 /* BlackBoard, from the TSP GPL sampling framework */
#define CN_DST_IDX 0x6
#define CN_DST_VAL 0x1
+#define CN_IDX_DM 0x7 /* Device Mapper */
+#define CN_VAL_DM_USERSPACE_LOG 0x1
-#define CN_NETLINK_USERS 7
+#define CN_NETLINK_USERS 8
/*
* Maximum connector's message size.
diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index 49c2362977fd..0d6310657f32 100644
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -11,6 +11,7 @@
#include <linux/bio.h>
#include <linux/blkdev.h>
+struct dm_dev;
struct dm_target;
struct dm_table;
struct mapped_device;
@@ -21,6 +22,7 @@ typedef enum { STATUSTYPE_INFO, STATUSTYPE_TABLE } status_type_t;
union map_info {
void *ptr;
unsigned long long ll;
+ unsigned flush_request;
};
/*
@@ -80,6 +82,15 @@ typedef int (*dm_ioctl_fn) (struct dm_target *ti, unsigned int cmd,
typedef int (*dm_merge_fn) (struct dm_target *ti, struct bvec_merge_data *bvm,
struct bio_vec *biovec, int max_size);
+typedef int (*iterate_devices_callout_fn) (struct dm_target *ti,
+ struct dm_dev *dev,
+ sector_t physical_start,
+ void *data);
+
+typedef int (*dm_iterate_devices_fn) (struct dm_target *ti,
+ iterate_devices_callout_fn fn,
+ void *data);
+
/*
* Returns:
* 0: The target can handle the next I/O immediately.
@@ -92,7 +103,8 @@ void dm_error(const char *message);
/*
* Combine device limits.
*/
-void dm_set_device_limits(struct dm_target *ti, struct block_device *bdev);
+int dm_set_device_limits(struct dm_target *ti, struct dm_dev *dev,
+ sector_t start, void *data);
struct dm_dev {
struct block_device *bdev;
@@ -138,23 +150,12 @@ struct target_type {
dm_ioctl_fn ioctl;
dm_merge_fn merge;
dm_busy_fn busy;
+ dm_iterate_devices_fn iterate_devices;
/* For internal device-mapper use. */
struct list_head list;
};
-struct io_restrictions {
- unsigned long bounce_pfn;
- unsigned long seg_boundary_mask;
- unsigned max_hw_sectors;
- unsigned max_sectors;
- unsigned max_segment_size;
- unsigned short logical_block_size;
- unsigned short max_hw_segments;
- unsigned short max_phys_segments;
- unsigned char no_cluster; /* inverted so that 0 is default */
-};
-
struct dm_target {
struct dm_table *table;
struct target_type *type;
@@ -163,15 +164,18 @@ struct dm_target {
sector_t begin;
sector_t len;
- /* FIXME: turn this into a mask, and merge with io_restrictions */
/* Always a power of 2 */
sector_t split_io;
/*
- * These are automatically filled in by
- * dm_table_get_device.
+ * A number of zero-length barrier requests that will be submitted
+ * to the target for the purpose of flushing cache.
+ *
+ * The request number will be placed in union map_info->flush_request.
+ * It is a responsibility of the target driver to remap these requests
+ * to the real underlying devices.
*/
- struct io_restrictions limits;
+ unsigned num_flush_requests;
/* target specific data */
void *private;
@@ -230,6 +234,7 @@ struct gendisk *dm_disk(struct mapped_device *md);
int dm_suspended(struct mapped_device *md);
int dm_noflush_suspending(struct dm_target *ti);
union map_info *dm_get_mapinfo(struct bio *bio);
+union map_info *dm_get_rq_mapinfo(struct request *rq);
/*
* Geometry functions.
@@ -392,4 +397,12 @@ static inline unsigned long to_bytes(sector_t n)
return (n << SECTOR_SHIFT);
}
+/*-----------------------------------------------------------------
+ * Helper for block layer and dm core operations
+ *---------------------------------------------------------------*/
+void dm_dispatch_request(struct request *rq);
+void dm_requeue_unmapped_request(struct request *rq);
+void dm_kill_unmapped_request(struct request *rq, int error);
+int dm_underlying_device_busy(struct request_queue *q);
+
#endif /* _LINUX_DEVICE_MAPPER_H */
diff --git a/include/linux/dm-ioctl.h b/include/linux/dm-ioctl.h
index 48e44ee2b466..2ab84c83c31a 100644
--- a/include/linux/dm-ioctl.h
+++ b/include/linux/dm-ioctl.h
@@ -123,6 +123,16 @@ struct dm_ioctl {
__u32 target_count; /* in/out */
__s32 open_count; /* out */
__u32 flags; /* in/out */
+
+ /*
+ * event_nr holds either the event number (input and output) or the
+ * udev cookie value (input only).
+ * The DM_DEV_WAIT ioctl takes an event number as input.
+ * The DM_SUSPEND, DM_DEV_REMOVE and DM_DEV_RENAME ioctls
+ * use the field as a cookie to return in the DM_COOKIE
+ * variable with the uevents they issue.
+ * For output, the ioctls return the event number, not the cookie.
+ */
__u32 event_nr; /* in/out */
__u32 padding;
@@ -256,9 +266,9 @@ enum {
#define DM_DEV_SET_GEOMETRY _IOWR(DM_IOCTL, DM_DEV_SET_GEOMETRY_CMD, struct dm_ioctl)
#define DM_VERSION_MAJOR 4
-#define DM_VERSION_MINOR 14
+#define DM_VERSION_MINOR 15
#define DM_VERSION_PATCHLEVEL 0
-#define DM_VERSION_EXTRA "-ioctl (2008-04-23)"
+#define DM_VERSION_EXTRA "-ioctl (2009-04-01)"
/* Status bits */
#define DM_READONLY_FLAG (1 << 0) /* In/Out */
diff --git a/include/linux/dm-log-userspace.h b/include/linux/dm-log-userspace.h
new file mode 100644
index 000000000000..642e3017b51f
--- /dev/null
+++ b/include/linux/dm-log-userspace.h
@@ -0,0 +1,386 @@
+/*
+ * Copyright (C) 2006-2009 Red Hat, Inc.
+ *
+ * This file is released under the LGPL.
+ */
+
+#ifndef __DM_LOG_USERSPACE_H__
+#define __DM_LOG_USERSPACE_H__
+
+#include <linux/dm-ioctl.h> /* For DM_UUID_LEN */
+
+/*
+ * The device-mapper userspace log module consists of a kernel component and
+ * a user-space component. The kernel component implements the API defined
+ * in dm-dirty-log.h. Its purpose is simply to pass the parameters and
+ * return values of those API functions between kernel and user-space.
+ *
+ * Below are defined the 'request_types' - DM_ULOG_CTR, DM_ULOG_DTR, etc.
+ * These request types represent the different functions in the device-mapper
+ * dirty log API. Each of these is described in more detail below.
+ *
+ * The user-space program must listen for requests from the kernel (representing
+ * the various API functions) and process them.
+ *
+ * User-space begins by setting up the communication link (error checking
+ * removed for clarity):
+ * fd = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_CONNECTOR);
+ * addr.nl_family = AF_NETLINK;
+ * addr.nl_groups = CN_IDX_DM;
+ * addr.nl_pid = 0;
+ * r = bind(fd, (struct sockaddr *) &addr, sizeof(addr));
+ * opt = addr.nl_groups;
+ * setsockopt(fd, SOL_NETLINK, NETLINK_ADD_MEMBERSHIP, &opt, sizeof(opt));
+ *
+ * User-space will then wait to receive requests form the kernel, which it
+ * will process as described below. The requests are received in the form,
+ * ((struct dm_ulog_request) + (additional data)). Depending on the request
+ * type, there may or may not be 'additional data'. In the descriptions below,
+ * you will see 'Payload-to-userspace' and 'Payload-to-kernel'. The
+ * 'Payload-to-userspace' is what the kernel sends in 'additional data' as
+ * necessary parameters to complete the request. The 'Payload-to-kernel' is
+ * the 'additional data' returned to the kernel that contains the necessary
+ * results of the request. The 'data_size' field in the dm_ulog_request
+ * structure denotes the availability and amount of payload data.
+ */
+
+/*
+ * DM_ULOG_CTR corresponds to (found in dm-dirty-log.h):
+ * int (*ctr)(struct dm_dirty_log *log, struct dm_target *ti,
+ * unsigned argc, char **argv);
+ *
+ * Payload-to-userspace:
+ * A single string containing all the argv arguments separated by ' 's
+ * Payload-to-kernel:
+ * None. ('data_size' in the dm_ulog_request struct should be 0.)
+ *
+ * The UUID contained in the dm_ulog_request structure is the reference that
+ * will be used by all request types to a specific log. The constructor must
+ * record this assotiation with instance created.
+ *
+ * When the request has been processed, user-space must return the
+ * dm_ulog_request to the kernel - setting the 'error' field and
+ * 'data_size' appropriately.
+ */
+#define DM_ULOG_CTR 1
+
+/*
+ * DM_ULOG_DTR corresponds to (found in dm-dirty-log.h):
+ * void (*dtr)(struct dm_dirty_log *log);
+ *
+ * Payload-to-userspace:
+ * A single string containing all the argv arguments separated by ' 's
+ * Payload-to-kernel:
+ * None. ('data_size' in the dm_ulog_request struct should be 0.)
+ *
+ * The UUID contained in the dm_ulog_request structure is all that is
+ * necessary to identify the log instance being destroyed. There is no
+ * payload data.
+ *
+ * When the request has been processed, user-space must return the
+ * dm_ulog_request to the kernel - setting the 'error' field and clearing
+ * 'data_size' appropriately.
+ */
+#define DM_ULOG_DTR 2
+
+/*
+ * DM_ULOG_PRESUSPEND corresponds to (found in dm-dirty-log.h):
+ * int (*presuspend)(struct dm_dirty_log *log);
+ *
+ * Payload-to-userspace:
+ * None.
+ * Payload-to-kernel:
+ * None.
+ *
+ * The UUID contained in the dm_ulog_request structure is all that is
+ * necessary to identify the log instance being presuspended. There is no
+ * payload data.
+ *
+ * When the request has been processed, user-space must return the
+ * dm_ulog_request to the kernel - setting the 'error' field and
+ * 'data_size' appropriately.
+ */
+#define DM_ULOG_PRESUSPEND 3
+
+/*
+ * DM_ULOG_POSTSUSPEND corresponds to (found in dm-dirty-log.h):
+ * int (*postsuspend)(struct dm_dirty_log *log);
+ *
+ * Payload-to-userspace:
+ * None.
+ * Payload-to-kernel:
+ * None.
+ *
+ * The UUID contained in the dm_ulog_request structure is all that is
+ * necessary to identify the log instance being postsuspended. There is no
+ * payload data.
+ *
+ * When the request has been processed, user-space must return the
+ * dm_ulog_request to the kernel - setting the 'error' field and
+ * 'data_size' appropriately.
+ */
+#define DM_ULOG_POSTSUSPEND 4
+
+/*
+ * DM_ULOG_RESUME corresponds to (found in dm-dirty-log.h):
+ * int (*resume)(struct dm_dirty_log *log);
+ *
+ * Payload-to-userspace:
+ * None.
+ * Payload-to-kernel:
+ * None.
+ *
+ * The UUID contained in the dm_ulog_request structure is all that is
+ * necessary to identify the log instance being resumed. There is no
+ * payload data.
+ *
+ * When the request has been processed, user-space must return the
+ * dm_ulog_request to the kernel - setting the 'error' field and
+ * 'data_size' appropriately.
+ */
+#define DM_ULOG_RESUME 5
+
+/*
+ * DM_ULOG_GET_REGION_SIZE corresponds to (found in dm-dirty-log.h):
+ * uint32_t (*get_region_size)(struct dm_dirty_log *log);
+ *
+ * Payload-to-userspace:
+ * None.
+ * Payload-to-kernel:
+ * uint64_t - contains the region size
+ *
+ * The region size is something that was determined at constructor time.
+ * It is returned in the payload area and 'data_size' is set to
+ * reflect this.
+ *
+ * When the request has been processed, user-space must return the
+ * dm_ulog_request to the kernel - setting the 'error' field appropriately.
+ */
+#define DM_ULOG_GET_REGION_SIZE 6
+
+/*
+ * DM_ULOG_IS_CLEAN corresponds to (found in dm-dirty-log.h):
+ * int (*is_clean)(struct dm_dirty_log *log, region_t region);
+ *
+ * Payload-to-userspace:
+ * uint64_t - the region to get clean status on
+ * Payload-to-kernel:
+ * int64_t - 1 if clean, 0 otherwise
+ *
+ * Payload is sizeof(uint64_t) and contains the region for which the clean
+ * status is being made.
+ *
+ * When the request has been processed, user-space must return the
+ * dm_ulog_request to the kernel - filling the payload with 0 (not clean) or
+ * 1 (clean), setting 'data_size' and 'error' appropriately.
+ */
+#define DM_ULOG_IS_CLEAN 7
+
+/*
+ * DM_ULOG_IN_SYNC corresponds to (found in dm-dirty-log.h):
+ * int (*in_sync)(struct dm_dirty_log *log, region_t region,
+ * int can_block);
+ *
+ * Payload-to-userspace:
+ * uint64_t - the region to get sync status on
+ * Payload-to-kernel:
+ * int64_t - 1 if in-sync, 0 otherwise
+ *
+ * Exactly the same as 'is_clean' above, except this time asking "has the
+ * region been recovered?" vs. "is the region not being modified?"
+ */
+#define DM_ULOG_IN_SYNC 8
+
+/*
+ * DM_ULOG_FLUSH corresponds to (found in dm-dirty-log.h):
+ * int (*flush)(struct dm_dirty_log *log);
+ *
+ * Payload-to-userspace:
+ * None.
+ * Payload-to-kernel:
+ * None.
+ *
+ * No incoming or outgoing payload. Simply flush log state to disk.
+ *
+ * When the request has been processed, user-space must return the
+ * dm_ulog_request to the kernel - setting the 'error' field and clearing
+ * 'data_size' appropriately.
+ */
+#define DM_ULOG_FLUSH 9
+
+/*
+ * DM_ULOG_MARK_REGION corresponds to (found in dm-dirty-log.h):
+ * void (*mark_region)(struct dm_dirty_log *log, region_t region);
+ *
+ * Payload-to-userspace:
+ * uint64_t [] - region(s) to mark
+ * Payload-to-kernel:
+ * None.
+ *
+ * Incoming payload contains the one or more regions to mark dirty.
+ * The number of regions contained in the payload can be determined from
+ * 'data_size/sizeof(uint64_t)'.
+ *
+ * When the request has been processed, user-space must return the
+ * dm_ulog_request to the kernel - setting the 'error' field and clearing
+ * 'data_size' appropriately.
+ */
+#define DM_ULOG_MARK_REGION 10
+
+/*
+ * DM_ULOG_CLEAR_REGION corresponds to (found in dm-dirty-log.h):
+ * void (*clear_region)(struct dm_dirty_log *log, region_t region);
+ *
+ * Payload-to-userspace:
+ * uint64_t [] - region(s) to clear
+ * Payload-to-kernel:
+ * None.
+ *
+ * Incoming payload contains the one or more regions to mark clean.
+ * The number of regions contained in the payload can be determined from
+ * 'data_size/sizeof(uint64_t)'.
+ *
+ * When the request has been processed, user-space must return the
+ * dm_ulog_request to the kernel - setting the 'error' field and clearing
+ * 'data_size' appropriately.
+ */
+#define DM_ULOG_CLEAR_REGION 11
+
+/*
+ * DM_ULOG_GET_RESYNC_WORK corresponds to (found in dm-dirty-log.h):
+ * int (*get_resync_work)(struct dm_dirty_log *log, region_t *region);
+ *
+ * Payload-to-userspace:
+ * None.
+ * Payload-to-kernel:
+ * {
+ * int64_t i; -- 1 if recovery necessary, 0 otherwise
+ * uint64_t r; -- The region to recover if i=1
+ * }
+ * 'data_size' should be set appropriately.
+ *
+ * When the request has been processed, user-space must return the
+ * dm_ulog_request to the kernel - setting the 'error' field appropriately.
+ */
+#define DM_ULOG_GET_RESYNC_WORK 12
+
+/*
+ * DM_ULOG_SET_REGION_SYNC corresponds to (found in dm-dirty-log.h):
+ * void (*set_region_sync)(struct dm_dirty_log *log,
+ * region_t region, int in_sync);
+ *
+ * Payload-to-userspace:
+ * {
+ * uint64_t - region to set sync state on
+ * int64_t - 0 if not-in-sync, 1 if in-sync
+ * }
+ * Payload-to-kernel:
+ * None.
+ *
+ * When the request has been processed, user-space must return the
+ * dm_ulog_request to the kernel - setting the 'error' field and clearing
+ * 'data_size' appropriately.
+ */
+#define DM_ULOG_SET_REGION_SYNC 13
+
+/*
+ * DM_ULOG_GET_SYNC_COUNT corresponds to (found in dm-dirty-log.h):
+ * region_t (*get_sync_count)(struct dm_dirty_log *log);
+ *
+ * Payload-to-userspace:
+ * None.
+ * Payload-to-kernel:
+ * uint64_t - the number of in-sync regions
+ *
+ * No incoming payload. Kernel-bound payload contains the number of
+ * regions that are in-sync (in a size_t).
+ *
+ * When the request has been processed, user-space must return the
+ * dm_ulog_request to the kernel - setting the 'error' field and
+ * 'data_size' appropriately.
+ */
+#define DM_ULOG_GET_SYNC_COUNT 14
+
+/*
+ * DM_ULOG_STATUS_INFO corresponds to (found in dm-dirty-log.h):
+ * int (*status)(struct dm_dirty_log *log, STATUSTYPE_INFO,
+ * char *result, unsigned maxlen);
+ *
+ * Payload-to-userspace:
+ * None.
+ * Payload-to-kernel:
+ * Character string containing STATUSTYPE_INFO
+ *
+ * When the request has been processed, user-space must return the
+ * dm_ulog_request to the kernel - setting the 'error' field and
+ * 'data_size' appropriately.
+ */
+#define DM_ULOG_STATUS_INFO 15
+
+/*
+ * DM_ULOG_STATUS_TABLE corresponds to (found in dm-dirty-log.h):
+ * int (*status)(struct dm_dirty_log *log, STATUSTYPE_TABLE,
+ * char *result, unsigned maxlen);
+ *
+ * Payload-to-userspace:
+ * None.
+ * Payload-to-kernel:
+ * Character string containing STATUSTYPE_TABLE
+ *
+ * When the request has been processed, user-space must return the
+ * dm_ulog_request to the kernel - setting the 'error' field and
+ * 'data_size' appropriately.
+ */
+#define DM_ULOG_STATUS_TABLE 16
+
+/*
+ * DM_ULOG_IS_REMOTE_RECOVERING corresponds to (found in dm-dirty-log.h):
+ * int (*is_remote_recovering)(struct dm_dirty_log *log, region_t region);
+ *
+ * Payload-to-userspace:
+ * uint64_t - region to determine recovery status on
+ * Payload-to-kernel:
+ * {
+ * int64_t is_recovering; -- 0 if no, 1 if yes
+ * uint64_t in_sync_hint; -- lowest region still needing resync
+ * }
+ *
+ * When the request has been processed, user-space must return the
+ * dm_ulog_request to the kernel - setting the 'error' field and
+ * 'data_size' appropriately.
+ */
+#define DM_ULOG_IS_REMOTE_RECOVERING 17
+
+/*
+ * (DM_ULOG_REQUEST_MASK & request_type) to get the request type
+ *
+ * Payload-to-userspace:
+ * A single string containing all the argv arguments separated by ' 's
+ * Payload-to-kernel:
+ * None. ('data_size' in the dm_ulog_request struct should be 0.)
+ *
+ * We are reserving 8 bits of the 32-bit 'request_type' field for the
+ * various request types above. The remaining 24-bits are currently
+ * set to zero and are reserved for future use and compatibility concerns.
+ *
+ * User-space should always use DM_ULOG_REQUEST_TYPE to aquire the
+ * request type from the 'request_type' field to maintain forward compatibility.
+ */
+#define DM_ULOG_REQUEST_MASK 0xFF
+#define DM_ULOG_REQUEST_TYPE(request_type) \
+ (DM_ULOG_REQUEST_MASK & (request_type))
+
+struct dm_ulog_request {
+ char uuid[DM_UUID_LEN]; /* Ties a request to a specific mirror log */
+ char padding[7]; /* Padding because DM_UUID_LEN = 129 */
+
+ int32_t error; /* Used to report back processing errors */
+
+ uint32_t seq; /* Sequence number for request */
+ uint32_t request_type; /* DM_ULOG_* defined above */
+ uint32_t data_size; /* How much data (not including this struct) */
+
+ char data[0];
+};
+
+#endif /* __DM_LOG_USERSPACE_H__ */

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