aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/staging/octeon/ethernet-mem.c
diff options
context:
space:
mode:
authorDavid Daney <ddaney@caviumnetworks.com>2010-01-27 13:22:53 -0800
committerRalf Baechle <ralf@linux-mips.org>2010-02-27 12:53:07 +0100
commit166bdaa9aad9903bf4330ef68feb37f220c9eac8 (patch)
tree2afbf9f99ff30c7276fe3ceb54477216e482bf0b /drivers/staging/octeon/ethernet-mem.c
parent6568a234363978e1aebb5b7c9840ed87eed20362 (diff)
Staging: Octeon Ethernet: Fix memory allocation.
After aligning the blocks returned by kmalloc, we need to save the original pointer so they can be correctly freed. There are no guarantees about the alignment of SKB data, so we need to handle worst case alignment. Since right shifts over subtraction have no distributive property, we need to fix the back pointer calculation. Signed-off-by: David Daney <ddaney@caviumnetworks.com> To: linux-mips@linux-mips.org Patchwork: http://patchwork.linux-mips.org/patch/884/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'drivers/staging/octeon/ethernet-mem.c')
-rw-r--r--drivers/staging/octeon/ethernet-mem.c45
1 files changed, 28 insertions, 17 deletions
diff --git a/drivers/staging/octeon/ethernet-mem.c b/drivers/staging/octeon/ethernet-mem.c
index 7090521471b2..53ed2f7ffdfd 100644
--- a/drivers/staging/octeon/ethernet-mem.c
+++ b/drivers/staging/octeon/ethernet-mem.c
@@ -4,7 +4,7 @@
* Contact: support@caviumnetworks.com
* This file is part of the OCTEON SDK
*
- * Copyright (c) 2003-2007 Cavium Networks
+ * Copyright (c) 2003-2010 Cavium Networks
*
* This file is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License, Version 2, as
@@ -45,7 +45,7 @@ static int cvm_oct_fill_hw_skbuff(int pool, int size, int elements)
int freed = elements;
while (freed) {
- struct sk_buff *skb = dev_alloc_skb(size + 128);
+ struct sk_buff *skb = dev_alloc_skb(size + 256);
if (unlikely(skb == NULL)) {
pr_warning
("Failed to allocate skb for hardware pool %d\n",
@@ -53,7 +53,7 @@ static int cvm_oct_fill_hw_skbuff(int pool, int size, int elements)
break;
}
- skb_reserve(skb, 128 - (((unsigned long)skb->data) & 0x7f));
+ skb_reserve(skb, 256 - (((unsigned long)skb->data) & 0x7f));
*(struct sk_buff **)(skb->data - sizeof(void *)) = skb;
cvmx_fpa_free(skb->data, pool, DONT_WRITEBACK(size / 128));
freed--;
@@ -91,10 +91,7 @@ static void cvm_oct_free_hw_skbuff(int pool, int size, int elements)
}
/**
- * This function fills a hardware pool with memory. Depending
- * on the config defines, this memory might come from the
- * kernel or global 32bit memory allocated with
- * cvmx_bootmem_alloc.
+ * This function fills a hardware pool with memory.
*
* @pool: Pool to populate
* @size: Size of each buffer in the pool
@@ -103,18 +100,29 @@ static void cvm_oct_free_hw_skbuff(int pool, int size, int elements)
static int cvm_oct_fill_hw_memory(int pool, int size, int elements)
{
char *memory;
+ char *fpa;
int freed = elements;
while (freed) {
- /* We need to force alignment to 128 bytes here */
- memory = kmalloc(size + 127, GFP_ATOMIC);
+ /*
+ * FPA memory must be 128 byte aligned. Since we are
+ * aligning we need to save the original pointer so we
+ * can feed it to kfree when the memory is returned to
+ * the kernel.
+ *
+ * We allocate an extra 256 bytes to allow for
+ * alignment and space for the original pointer saved
+ * just before the block.
+ */
+ memory = kmalloc(size + 256, GFP_ATOMIC);
if (unlikely(memory == NULL)) {
pr_warning("Unable to allocate %u bytes for FPA pool %d\n",
elements * size, pool);
break;
}
- memory = (char *)(((unsigned long)memory + 127) & -128);
- cvmx_fpa_free(memory, pool, 0);
+ fpa = (char *)(((unsigned long)memory + 256) & ~0x7fUL);
+ *((char **)fpa - 1) = memory;
+ cvmx_fpa_free(fpa, pool, 0);
freed--;
}
return elements - freed;
@@ -130,13 +138,16 @@ static int cvm_oct_fill_hw_memory(int pool, int size, int elements)
static void cvm_oct_free_hw_memory(int pool, int size, int elements)
{
char *memory;
+ char *fpa;
do {
- memory = cvmx_fpa_alloc(pool);
- if (memory) {
+ fpa = cvmx_fpa_alloc(pool);
+ if (fpa) {
elements--;
- kfree(phys_to_virt(cvmx_ptr_to_phys(memory)));
+ fpa = (char *)phys_to_virt(cvmx_ptr_to_phys(fpa));
+ memory = *((char **)fpa - 1);
+ kfree(memory);
}
- } while (memory);
+ } while (fpa);
if (elements < 0)
pr_warning("Freeing of pool %u had too many buffers (%d)\n",
@@ -149,7 +160,7 @@ static void cvm_oct_free_hw_memory(int pool, int size, int elements)
int cvm_oct_mem_fill_fpa(int pool, int size, int elements)
{
int freed;
- if (USE_SKBUFFS_IN_HW)
+ if (USE_SKBUFFS_IN_HW && pool == CVMX_FPA_PACKET_POOL)
freed = cvm_oct_fill_hw_skbuff(pool, size, elements);
else
freed = cvm_oct_fill_hw_memory(pool, size, elements);
@@ -158,7 +169,7 @@ int cvm_oct_mem_fill_fpa(int pool, int size, int elements)
void cvm_oct_mem_empty_fpa(int pool, int size, int elements)
{
- if (USE_SKBUFFS_IN_HW)
+ if (USE_SKBUFFS_IN_HW && pool == CVMX_FPA_PACKET_POOL)
cvm_oct_free_hw_skbuff(pool, size, elements);
else
cvm_oct_free_hw_memory(pool, size, elements);

Privacy Policy