Instead of using the at/$1 register (which does not form part of the
typical calling convention) to provide the end of the source region to
__copy_user* functions, use the a3/$7 register. This prepares us for
being able to call __copy_user* with a standard function call.
Signed-off-by: Paul Burton <paul.burton@xxxxxxxxxx>
---
arch/mips/cavium-octeon/octeon-memcpy.S | 8 ++++----
arch/mips/include/asm/uaccess.h | 21 ++++++++++++---------
arch/mips/lib/memcpy.S | 8 ++++----
3 files changed, 20 insertions(+), 17 deletions(-)
diff --git a/arch/mips/cavium-octeon/octeon-memcpy.S b/arch/mips/cavium-octeon/octeon-memcpy.S
index db49fca..9316ab1 100644
--- a/arch/mips/cavium-octeon/octeon-memcpy.S
+++ b/arch/mips/cavium-octeon/octeon-memcpy.S
@@ -57,13 +57,13 @@
/*
* The exception handler for loads requires that:
- * 1- AT contain the address of the byte just past the end of the source
+ * 1- a3 contain the address of the byte just past the end of the source
* of the copy,
- * 2- src_entry <= src < AT, and
+ * 2- src_entry <= src < a3, and
* 3- (dst - src) == (dst_entry - src_entry),
* The _entry suffix denotes values when __copy_user was called.
*
- * (1) is set up up by uaccess.h and maintained by not writing AT in copy_user
+ * (1) is set up up by uaccess.h and maintained by not writing a3 in copy_user
* (2) is met by incrementing src by the number of bytes copied
* (3) is met by not doing loads between a pair of increments of dst and src
*
@@ -386,7 +386,7 @@ EXC( lb t1, 0(src), l_exc)
l_exc:
LOAD t0, TI_TASK($28)
LOAD t0, THREAD_BUADDR(t0) # t0 is just past last good address
- SUB len, AT, t0 # len number of uncopied bytes
+ SUB len, a3, t0 # len number of uncopied bytes
bnez ta0, 2f /* Skip the zeroing out part if inatomic */
/*
* Here's where we rely on src and dst being incremented in tandem,
diff --git a/arch/mips/include/asm/uaccess.h b/arch/mips/include/asm/uaccess.h
index 81d632f..562ad49 100644
--- a/arch/mips/include/asm/uaccess.h
+++ b/arch/mips/include/asm/uaccess.h
@@ -809,7 +809,8 @@ extern void __put_user_unaligned_unknown(void);
#define DADDI_SCRATCH "$0"
#endif
-extern size_t __copy_user(void *__to, const void *__from, size_t __n);
+extern size_t __copy_user(void *__to, const void *__from, size_t __n,
+ const void *__from_end);
#ifndef CONFIG_EVA
#define __invoke_copy_to_user(to, from, n) \
@@ -874,7 +875,8 @@ extern size_t __copy_user(void *__to, const void *__from, size_t __n);
__cu_len; \
})
-extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n);
+extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n,
+ const void *__from_end);
#define __copy_to_user_inatomic(to, from, n) \
({ \
@@ -977,7 +979,7 @@ extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n);
".set\tnoreorder\n\t" \
__MODULE_JAL(__copy_user) \
".set\tnoat\n\t" \
- __UA_ADDU "\t$1, %1, %2\n\t" \
+ __UA_ADDU "\t$7, %1, %2\n\t" \
".set\tat\n\t" \
".set\treorder" \
: "=r"(__cu_ret_r), "+r" (__cu_to_r), \
@@ -1013,7 +1015,7 @@ extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n);
".set\tnoreorder\n\t" \
__MODULE_JAL(__copy_user_inatomic) \
".set\tnoat\n\t" \
- __UA_ADDU "\t$1, %1, %2\n\t" \
+ __UA_ADDU "\t$7, %1, %2\n\t" \
".set\tat\n\t" \
".set\treorder" \
: "=r"(__cu_ret_r), "+r" (__cu_to_r), \
@@ -1032,12 +1034,13 @@ extern size_t __copy_user_inatomic(void *__to, const void *__from, size_t __n);
/* EVA specific functions */
extern size_t __copy_user_inatomic_eva(void *__to, const void *__from,
- size_t __n);
+ size_t __n, const void *__from_end);
extern size_t __copy_from_user_eva(void *__to, const void *__from,
- size_t __n);
+ size_t __n, const void *__from_end);
extern size_t __copy_to_user_eva(void *__to, const void *__from,
- size_t __n);
-extern size_t __copy_in_user_eva(void *__to, const void *__from, size_t __n);
+ size_t __n, const void *__from_end);
+extern size_t __copy_in_user_eva(void *__to, const void *__from, size_t __n,
+ const void *__from_end);
#define __invoke_copy_from_user_eva_generic(to, from, n, func_ptr) \
({ \
@@ -1053,7 +1056,7 @@ extern size_t __copy_in_user_eva(void *__to, const void *__from, size_t __n);
".set\tnoreorder\n\t" \
__MODULE_JAL(func_ptr) \
".set\tnoat\n\t" \
- __UA_ADDU "\t$1, %1, %2\n\t" \
+ __UA_ADDU "\t$7, %1, %2\n\t" \
".set\tat\n\t" \
".set\treorder" \
: "=r"(__cu_ret_r), "+r" (__cu_to_r), \
diff --git a/arch/mips/lib/memcpy.S b/arch/mips/lib/memcpy.S
index 48684c4..5af9f03 100644
--- a/arch/mips/lib/memcpy.S
+++ b/arch/mips/lib/memcpy.S
@@ -70,13 +70,13 @@
/*
* The exception handler for loads requires that:
- * 1- AT contain the address of the byte just past the end of the source
+ * 1- a3 contain the address of the byte just past the end of the source
* of the copy,
- * 2- src_entry <= src < AT, and
+ * 2- src_entry <= src < a3, and
* 3- (dst - src) == (dst_entry - src_entry),
* The _entry suffix denotes values when __copy_user was called.
*
- * (1) is set up up by uaccess.h and maintained by not writing AT in copy_user
+ * (1) is set up up by uaccess.h and maintained by not writing a3 in copy_user
* (2) is met by incrementing src by the number of bytes copied
* (3) is met by not doing loads between a pair of increments of dst and src
*
@@ -549,7 +549,7 @@
nop
LOADK t0, THREAD_BUADDR(t0) # t0 is just past last good address
nop
- SUB len, AT, t0 # len number of uncopied bytes
+ SUB len, a3, t0 # len number of uncopied bytes
bnez ta2, .Ldone\@ /* Skip the zeroing part if inatomic */
/*
* Here's where we rely on src and dst being incremented in tandem,
--
2.10.2
