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author | Mark Rutland <mark.rutland@arm.com> | 2020-12-02 16:15:52 +0300 |
---|---|---|
committer | Catalin Marinas <catalin.marinas@arm.com> | 2020-12-02 22:49:11 +0300 |
commit | f253d827f33cb5a5990b5cfd271941d1a21ecd85 (patch) | |
tree | 1e97083ea9211dee97c671036f00717fe706595d /arch/arm64 | |
parent | 9e94fdade4d8f3c9b64c302ba081e2718c9e4087 (diff) | |
download | linux-f253d827f33cb5a5990b5cfd271941d1a21ecd85.tar.xz |
arm64: uaccess: refactor __{get,put}_user
As a step towards implementing __{get,put}_kernel_nofault(), this patch
splits most user-memory specific logic out of __{get,put}_user(), with
the memory access and fault handling in new __{raw_get,put}_mem()
helpers.
For now the LDR/LDTR patching is left within the *get_mem() helpers, and
will be removed in a subsequent patch.
There should be no functional change as a result of this patch.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: James Morse <james.morse@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20201202131558.39270-7-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64')
-rw-r--r-- | arch/arm64/include/asm/uaccess.h | 44 |
1 files changed, 27 insertions, 17 deletions
diff --git a/arch/arm64/include/asm/uaccess.h b/arch/arm64/include/asm/uaccess.h index d6a4e496ebc6..743f209d3fab 100644 --- a/arch/arm64/include/asm/uaccess.h +++ b/arch/arm64/include/asm/uaccess.h @@ -253,7 +253,7 @@ static inline void __user *__uaccess_mask_ptr(const void __user *ptr) * The "__xxx_error" versions set the third argument to -EFAULT if an error * occurs, and leave it unchanged on success. */ -#define __get_user_asm(instr, alt_instr, reg, x, addr, err, feature) \ +#define __get_mem_asm(instr, alt_instr, reg, x, addr, err, feature) \ asm volatile( \ "1:"ALTERNATIVE(instr " " reg "1, [%2]\n", \ alt_instr " " reg "1, [%2]\n", feature) \ @@ -268,35 +268,40 @@ static inline void __user *__uaccess_mask_ptr(const void __user *ptr) : "+r" (err), "=&r" (x) \ : "r" (addr), "i" (-EFAULT)) -#define __raw_get_user(x, ptr, err) \ +#define __raw_get_mem(x, ptr, err) \ do { \ unsigned long __gu_val; \ - __chk_user_ptr(ptr); \ - uaccess_enable_not_uao(); \ switch (sizeof(*(ptr))) { \ case 1: \ - __get_user_asm("ldrb", "ldtrb", "%w", __gu_val, (ptr), \ + __get_mem_asm("ldrb", "ldtrb", "%w", __gu_val, (ptr), \ (err), ARM64_HAS_UAO); \ break; \ case 2: \ - __get_user_asm("ldrh", "ldtrh", "%w", __gu_val, (ptr), \ + __get_mem_asm("ldrh", "ldtrh", "%w", __gu_val, (ptr), \ (err), ARM64_HAS_UAO); \ break; \ case 4: \ - __get_user_asm("ldr", "ldtr", "%w", __gu_val, (ptr), \ + __get_mem_asm("ldr", "ldtr", "%w", __gu_val, (ptr), \ (err), ARM64_HAS_UAO); \ break; \ case 8: \ - __get_user_asm("ldr", "ldtr", "%x", __gu_val, (ptr), \ + __get_mem_asm("ldr", "ldtr", "%x", __gu_val, (ptr), \ (err), ARM64_HAS_UAO); \ break; \ default: \ BUILD_BUG(); \ } \ - uaccess_disable_not_uao(); \ (x) = (__force __typeof__(*(ptr)))__gu_val; \ } while (0) +#define __raw_get_user(x, ptr, err) \ +do { \ + __chk_user_ptr(ptr); \ + uaccess_enable_not_uao(); \ + __raw_get_mem(x, ptr, err); \ + uaccess_disable_not_uao(); \ +} while (0) + #define __get_user_error(x, ptr, err) \ do { \ __typeof__(*(ptr)) __user *__p = (ptr); \ @@ -318,7 +323,7 @@ do { \ #define get_user __get_user -#define __put_user_asm(instr, alt_instr, reg, x, addr, err, feature) \ +#define __put_mem_asm(instr, alt_instr, reg, x, addr, err, feature) \ asm volatile( \ "1:"ALTERNATIVE(instr " " reg "1, [%2]\n", \ alt_instr " " reg "1, [%2]\n", feature) \ @@ -332,31 +337,36 @@ do { \ : "+r" (err) \ : "r" (x), "r" (addr), "i" (-EFAULT)) -#define __raw_put_user(x, ptr, err) \ +#define __raw_put_mem(x, ptr, err) \ do { \ __typeof__(*(ptr)) __pu_val = (x); \ - __chk_user_ptr(ptr); \ - uaccess_enable_not_uao(); \ switch (sizeof(*(ptr))) { \ case 1: \ - __put_user_asm("strb", "sttrb", "%w", __pu_val, (ptr), \ + __put_mem_asm("strb", "sttrb", "%w", __pu_val, (ptr), \ (err), ARM64_HAS_UAO); \ break; \ case 2: \ - __put_user_asm("strh", "sttrh", "%w", __pu_val, (ptr), \ + __put_mem_asm("strh", "sttrh", "%w", __pu_val, (ptr), \ (err), ARM64_HAS_UAO); \ break; \ case 4: \ - __put_user_asm("str", "sttr", "%w", __pu_val, (ptr), \ + __put_mem_asm("str", "sttr", "%w", __pu_val, (ptr), \ (err), ARM64_HAS_UAO); \ break; \ case 8: \ - __put_user_asm("str", "sttr", "%x", __pu_val, (ptr), \ + __put_mem_asm("str", "sttr", "%x", __pu_val, (ptr), \ (err), ARM64_HAS_UAO); \ break; \ default: \ BUILD_BUG(); \ } \ +} while (0) + +#define __raw_put_user(x, ptr, err) \ +do { \ + __chk_user_ptr(ptr); \ + uaccess_enable_not_uao(); \ + __raw_put_mem(x, ptr, err); \ uaccess_disable_not_uao(); \ } while (0) |