aboutsummaryrefslogtreecommitdiffstats
path: root/arch/s390/include
diff options
context:
space:
mode:
authorMartin Schwidefsky <schwidefsky@de.ibm.com>2016-01-26 14:10:34 +0100
committerMartin Schwidefsky <schwidefsky@de.ibm.com>2017-03-22 08:14:25 +0100
commit916cda1aa1b412d7cf2991c3af7479544942d121 (patch)
tree51e373acacf962c1635899f1567484be0baed745 /arch/s390/include
parent093b995e3b55a0ae0670226ddfcb05bfbf0099ae (diff)
s390: add a system call for guarded storage
This adds a new system call to enable the use of guarded storage for user space processes. The system call takes two arguments, a command and pointer to a guarded storage control block: s390_guarded_storage(int command, struct gs_cb *gs_cb); The second argument is relevant only for the GS_SET_BC_CB command. The commands in detail: 0 - GS_ENABLE Enable the guarded storage facility for the current task. The initial content of the guarded storage control block will be all zeros. After the enablement the user space code can use load-guarded-storage-controls instruction (LGSC) to load an arbitrary control block. While a task is enabled the kernel will save and restore the current content of the guarded storage registers on context switch. 1 - GS_DISABLE Disables the use of the guarded storage facility for the current task. The kernel will cease to save and restore the content of the guarded storage registers, the task specific content of these registers is lost. 2 - GS_SET_BC_CB Set a broadcast guarded storage control block. This is called per thread and stores a specific guarded storage control block in the task struct of the current task. This control block will be used for the broadcast event GS_BROADCAST. 3 - GS_CLEAR_BC_CB Clears the broadcast guarded storage control block. The guarded- storage control block is removed from the task struct that was established by GS_SET_BC_CB. 4 - GS_BROADCAST Sends a broadcast to all thread siblings of the current task. Every sibling that has established a broadcast guarded storage control block will load this control block and will be enabled for guarded storage. The broadcast guarded storage control block is used up, a second broadcast without a refresh of the stored control block with GS_SET_BC_CB will not have any effect. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/include')
-rw-r--r--arch/s390/include/asm/elf.h1
-rw-r--r--arch/s390/include/asm/lowcore.h9
-rw-r--r--arch/s390/include/asm/nmi.h12
-rw-r--r--arch/s390/include/asm/processor.h5
-rw-r--r--arch/s390/include/asm/setup.h2
-rw-r--r--arch/s390/include/asm/switch_to.h3
-rw-r--r--arch/s390/include/asm/thread_info.h12
-rw-r--r--arch/s390/include/uapi/asm/Kbuild1
-rw-r--r--arch/s390/include/uapi/asm/guarded_storage.h77
-rw-r--r--arch/s390/include/uapi/asm/unistd.h2
10 files changed, 111 insertions, 13 deletions
diff --git a/arch/s390/include/asm/elf.h b/arch/s390/include/asm/elf.h
index 1d48880b3cc1..e8f623041769 100644
--- a/arch/s390/include/asm/elf.h
+++ b/arch/s390/include/asm/elf.h
@@ -105,6 +105,7 @@
#define HWCAP_S390_VXRS 2048
#define HWCAP_S390_VXRS_BCD 4096
#define HWCAP_S390_VXRS_EXT 8192
+#define HWCAP_S390_GS 16384
/* Internal bits, not exposed via elf */
#define HWCAP_INT_SIE 1UL
diff --git a/arch/s390/include/asm/lowcore.h b/arch/s390/include/asm/lowcore.h
index 61261e0e95c0..8a5b082797f8 100644
--- a/arch/s390/include/asm/lowcore.h
+++ b/arch/s390/include/asm/lowcore.h
@@ -157,8 +157,8 @@ struct lowcore {
__u64 stfle_fac_list[32]; /* 0x0f00 */
__u8 pad_0x1000[0x11b0-0x1000]; /* 0x1000 */
- /* Pointer to vector register save area */
- __u64 vector_save_area_addr; /* 0x11b0 */
+ /* Pointer to the machine check extended save area */
+ __u64 mcesad; /* 0x11b0 */
/* 64 bit extparam used for pfault/diag 250: defined by architecture */
__u64 ext_params2; /* 0x11B8 */
@@ -182,10 +182,7 @@ struct lowcore {
/* Transaction abort diagnostic block */
__u8 pgm_tdb[256]; /* 0x1800 */
- __u8 pad_0x1900[0x1c00-0x1900]; /* 0x1900 */
-
- /* Software defined save area for vector registers */
- __u8 vector_save_area[1024]; /* 0x1c00 */
+ __u8 pad_0x1900[0x2000-0x1900]; /* 0x1900 */
} __packed;
#define S390_lowcore (*((struct lowcore *) 0))
diff --git a/arch/s390/include/asm/nmi.h b/arch/s390/include/asm/nmi.h
index b75fd910386a..e3e8895f5d3e 100644
--- a/arch/s390/include/asm/nmi.h
+++ b/arch/s390/include/asm/nmi.h
@@ -58,7 +58,9 @@ union mci {
u64 ie : 1; /* 32 indirect storage error */
u64 ar : 1; /* 33 access register validity */
u64 da : 1; /* 34 delayed access exception */
- u64 : 7; /* 35-41 */
+ u64 : 1; /* 35 */
+ u64 gs : 1; /* 36 guarded storage registers */
+ u64 : 5; /* 37-41 */
u64 pr : 1; /* 42 tod programmable register validity */
u64 fc : 1; /* 43 fp control register validity */
u64 ap : 1; /* 44 ancillary report */
@@ -69,6 +71,14 @@ union mci {
};
};
+#define MCESA_ORIGIN_MASK (~0x3ffUL)
+#define MCESA_LC_MASK (0xfUL)
+
+struct mcesa {
+ u8 vector_save_area[1024];
+ u8 guarded_storage_save_area[32];
+};
+
struct pt_regs;
extern void s390_handle_mcck(void);
diff --git a/arch/s390/include/asm/processor.h b/arch/s390/include/asm/processor.h
index e4988710aa86..cc101f9371cb 100644
--- a/arch/s390/include/asm/processor.h
+++ b/arch/s390/include/asm/processor.h
@@ -135,6 +135,8 @@ struct thread_struct {
struct list_head list;
/* cpu runtime instrumentation */
struct runtime_instr_cb *ri_cb;
+ struct gs_cb *gs_cb; /* Current guarded storage cb */
+ struct gs_cb *gs_bc_cb; /* Broadcast guarded storage cb */
unsigned char trap_tdb[256]; /* Transaction abort diagnose block */
/*
* Warning: 'fpu' is dynamically-sized. It *MUST* be at
@@ -215,6 +217,9 @@ void show_cacheinfo(struct seq_file *m);
/* Free all resources held by a thread. */
extern void release_thread(struct task_struct *);
+/* Free guarded storage control block for current */
+void exit_thread_gs(void);
+
/*
* Return saved PC of a blocked thread.
*/
diff --git a/arch/s390/include/asm/setup.h b/arch/s390/include/asm/setup.h
index 30bdb5a027f3..383bd8358a8c 100644
--- a/arch/s390/include/asm/setup.h
+++ b/arch/s390/include/asm/setup.h
@@ -31,6 +31,7 @@
#define MACHINE_FLAG_VX _BITUL(13)
#define MACHINE_FLAG_CAD _BITUL(14)
#define MACHINE_FLAG_NX _BITUL(15)
+#define MACHINE_FLAG_GS _BITUL(16)
#define LPP_MAGIC _BITUL(31)
#define LPP_PFAULT_PID_MASK _AC(0xffffffff, UL)
@@ -70,6 +71,7 @@ extern void detect_memory_memblock(void);
#define MACHINE_HAS_VX (S390_lowcore.machine_flags & MACHINE_FLAG_VX)
#define MACHINE_HAS_CAD (S390_lowcore.machine_flags & MACHINE_FLAG_CAD)
#define MACHINE_HAS_NX (S390_lowcore.machine_flags & MACHINE_FLAG_NX)
+#define MACHINE_HAS_GS (S390_lowcore.machine_flags & MACHINE_FLAG_GS)
/*
* Console mode. Override with conmode=
diff --git a/arch/s390/include/asm/switch_to.h b/arch/s390/include/asm/switch_to.h
index 12d45f0cfdd9..f6c2b5814ab0 100644
--- a/arch/s390/include/asm/switch_to.h
+++ b/arch/s390/include/asm/switch_to.h
@@ -10,6 +10,7 @@
#include <linux/thread_info.h>
#include <asm/fpu/api.h>
#include <asm/ptrace.h>
+#include <asm/guarded_storage.h>
extern struct task_struct *__switch_to(void *, void *);
extern void update_cr_regs(struct task_struct *task);
@@ -33,12 +34,14 @@ static inline void restore_access_regs(unsigned int *acrs)
save_fpu_regs(); \
save_access_regs(&prev->thread.acrs[0]); \
save_ri_cb(prev->thread.ri_cb); \
+ save_gs_cb(prev->thread.gs_cb); \
} \
if (next->mm) { \
update_cr_regs(next); \
set_cpu_flag(CIF_FPU); \
restore_access_regs(&next->thread.acrs[0]); \
restore_ri_cb(next->thread.ri_cb, prev->thread.ri_cb); \
+ restore_gs_cb(next->thread.gs_cb); \
} \
prev = __switch_to(prev,next); \
} while (0)
diff --git a/arch/s390/include/asm/thread_info.h b/arch/s390/include/asm/thread_info.h
index a5b54a445eb8..f36e6e2b73f0 100644
--- a/arch/s390/include/asm/thread_info.h
+++ b/arch/s390/include/asm/thread_info.h
@@ -54,11 +54,12 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
#define TIF_NOTIFY_RESUME 0 /* callback before returning to user */
#define TIF_SIGPENDING 1 /* signal pending */
#define TIF_NEED_RESCHED 2 /* rescheduling necessary */
-#define TIF_SYSCALL_TRACE 3 /* syscall trace active */
-#define TIF_SYSCALL_AUDIT 4 /* syscall auditing active */
-#define TIF_SECCOMP 5 /* secure computing */
-#define TIF_SYSCALL_TRACEPOINT 6 /* syscall tracepoint instrumentation */
-#define TIF_UPROBE 7 /* breakpointed or single-stepping */
+#define TIF_UPROBE 3 /* breakpointed or single-stepping */
+#define TIF_GUARDED_STORAGE 4 /* load guarded storage control block */
+#define TIF_SYSCALL_TRACE 8 /* syscall trace active */
+#define TIF_SYSCALL_AUDIT 9 /* syscall auditing active */
+#define TIF_SECCOMP 10 /* secure computing */
+#define TIF_SYSCALL_TRACEPOINT 11 /* syscall tracepoint instrumentation */
#define TIF_31BIT 16 /* 32bit process */
#define TIF_MEMDIE 17 /* is terminating due to OOM killer */
#define TIF_RESTORE_SIGMASK 18 /* restore signal mask in do_signal() */
@@ -76,5 +77,6 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src);
#define _TIF_UPROBE _BITUL(TIF_UPROBE)
#define _TIF_31BIT _BITUL(TIF_31BIT)
#define _TIF_SINGLE_STEP _BITUL(TIF_SINGLE_STEP)
+#define _TIF_GUARDED_STORAGE _BITUL(TIF_GUARDED_STORAGE)
#endif /* _ASM_THREAD_INFO_H */
diff --git a/arch/s390/include/uapi/asm/Kbuild b/arch/s390/include/uapi/asm/Kbuild
index 6848ba5c1454..86b761e583e3 100644
--- a/arch/s390/include/uapi/asm/Kbuild
+++ b/arch/s390/include/uapi/asm/Kbuild
@@ -12,6 +12,7 @@ header-y += dasd.h
header-y += debug.h
header-y += errno.h
header-y += fcntl.h
+header-y += guarded_storage.h
header-y += hypfs.h
header-y += ioctl.h
header-y += ioctls.h
diff --git a/arch/s390/include/uapi/asm/guarded_storage.h b/arch/s390/include/uapi/asm/guarded_storage.h
new file mode 100644
index 000000000000..852850e8e17e
--- /dev/null
+++ b/arch/s390/include/uapi/asm/guarded_storage.h
@@ -0,0 +1,77 @@
+#ifndef _GUARDED_STORAGE_H
+#define _GUARDED_STORAGE_H
+
+#include <linux/types.h>
+
+struct gs_cb {
+ __u64 reserved;
+ __u64 gsd;
+ __u64 gssm;
+ __u64 gs_epl_a;
+};
+
+struct gs_epl {
+ __u8 pad1;
+ union {
+ __u8 gs_eam;
+ struct {
+ __u8 : 6;
+ __u8 e : 1;
+ __u8 b : 1;
+ };
+ };
+ union {
+ __u8 gs_eci;
+ struct {
+ __u8 tx : 1;
+ __u8 cx : 1;
+ __u8 : 5;
+ __u8 in : 1;
+ };
+ };
+ union {
+ __u8 gs_eai;
+ struct {
+ __u8 : 1;
+ __u8 t : 1;
+ __u8 as : 2;
+ __u8 ar : 4;
+ };
+ };
+ __u32 pad2;
+ __u64 gs_eha;
+ __u64 gs_eia;
+ __u64 gs_eoa;
+ __u64 gs_eir;
+ __u64 gs_era;
+};
+
+#define GS_ENABLE 0
+#define GS_DISABLE 1
+#define GS_SET_BC_CB 2
+#define GS_CLEAR_BC_CB 3
+#define GS_BROADCAST 4
+
+static inline void load_gs_cb(struct gs_cb *gs_cb)
+{
+ asm volatile(".insn rxy,0xe3000000004d,0,%0" : : "Q" (*gs_cb));
+}
+
+static inline void store_gs_cb(struct gs_cb *gs_cb)
+{
+ asm volatile(".insn rxy,0xe30000000049,0,%0" : : "Q" (*gs_cb));
+}
+
+static inline void save_gs_cb(struct gs_cb *gs_cb)
+{
+ if (gs_cb)
+ store_gs_cb(gs_cb);
+}
+
+static inline void restore_gs_cb(struct gs_cb *gs_cb)
+{
+ if (gs_cb)
+ load_gs_cb(gs_cb);
+}
+
+#endif /* _GUARDED_STORAGE_H */
diff --git a/arch/s390/include/uapi/asm/unistd.h b/arch/s390/include/uapi/asm/unistd.h
index 152de9b796e1..ea42290e7d51 100644
--- a/arch/s390/include/uapi/asm/unistd.h
+++ b/arch/s390/include/uapi/asm/unistd.h
@@ -313,7 +313,7 @@
#define __NR_copy_file_range 375
#define __NR_preadv2 376
#define __NR_pwritev2 377
-/* Number 378 is reserved for guarded storage */
+#define __NR_s390_guarded_storage 378
#define __NR_statx 379
#define NR_syscalls 380

Privacy Policy