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| author |   Al Viro <viro@zeniv.linux.org.uk> | 2020-07-12 22:56:34 -0400 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2020-08-20 15:45:16 -0400 |
| commit | 1d60be3c25edf4b9554fdb02aa6fb6fd75695aa7 (patch) | |
| tree | 4a7c40fc3b387fa5b4c7ae95ba223cf432f55016 /arch/arm/lib | |
| parent | alpha: propagate the calling convention changes down to csum_partial_copy.c helpers (diff) | |
| download | linux-dev-1d60be3c25edf4b9554fdb02aa6fb6fd75695aa7.tar.xz linux-dev-1d60be3c25edf4b9554fdb02aa6fb6fd75695aa7.zip | |
arm: propagate the calling convention changes down to csum_partial_copy_from_user()
... and get rid of the "clean the destination on error" crap.
Simplifies the fault handlers and the function itself...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'arch/arm/lib')
| -rw-r--r-- | arch/arm/lib/csumpartialcopy.S | 1 | ||||
| -rw-r--r-- | arch/arm/lib/csumpartialcopygeneric.S | 1 | ||||
| -rw-r--r-- | arch/arm/lib/csumpartialcopyuser.S | 26 |
3 files changed, 7 insertions, 21 deletions
diff --git a/arch/arm/lib/csumpartialcopy.S b/arch/arm/lib/csumpartialcopy.S index aab914fbc86b..1ca6aadd649c 100644 --- a/arch/arm/lib/csumpartialcopy.S +++ b/arch/arm/lib/csumpartialcopy.S @@ -16,7 +16,6 @@ .macro save_regs stmfd sp!, {r1, r4 - r8, lr} - mov r3, #0 .endm .macro load_regs diff --git a/arch/arm/lib/csumpartialcopygeneric.S b/arch/arm/lib/csumpartialcopygeneric.S index 0b706a39a677..0fd5c10e90a7 100644 --- a/arch/arm/lib/csumpartialcopygeneric.S +++ b/arch/arm/lib/csumpartialcopygeneric.S @@ -86,6 +86,7 @@ sum .req r3 FN_ENTRY save_regs + mov sum, #-1 cmp len, #8 @ Ensure that we have at least blo .Lless8 @ 8 bytes to copy. diff --git a/arch/arm/lib/csumpartialcopyuser.S b/arch/arm/lib/csumpartialcopyuser.S index 6bd3a93eaa3c..6928781e6bee 100644 --- a/arch/arm/lib/csumpartialcopyuser.S +++ b/arch/arm/lib/csumpartialcopyuser.S @@ -62,9 +62,9 @@ /* * unsigned int - * csum_partial_copy_from_user(const char *src, char *dst, int len, int sum, int *err_ptr) - * r0 = src, r1 = dst, r2 = len, r3 = sum, [sp] = *err_ptr - * Returns : r0 = checksum, [[sp, #0], #0] = 0 or -EFAULT + * csum_partial_copy_from_user(const char *src, char *dst, int len) + * r0 = src, r1 = dst, r2 = len + * Returns : r0 = checksum or 0 */ #define FN_ENTRY ENTRY(csum_partial_copy_from_user) @@ -73,25 +73,11 @@ #include "csumpartialcopygeneric.S" /* - * FIXME: minor buglet here - * We don't return the checksum for the data present in the buffer. To do - * so properly, we would have to add in whatever registers were loaded before - * the fault, which, with the current asm above is not predictable. + * We report fault by returning 0 csum - impossible in normal case, since + * we start with 0xffffffff for initial sum. */ .pushsection .text.fixup,"ax" .align 4 -9001: mov r4, #-EFAULT -#ifdef CONFIG_CPU_SW_DOMAIN_PAN - ldr r5, [sp, #9*4] @ *err_ptr -#else - ldr r5, [sp, #8*4] @ *err_ptr -#endif - str r4, [r5] - ldmia sp, {r1, r2} @ retrieve dst, len - add r2, r2, r1 - mov r0, #0 @ zero the buffer -9002: teq r2, r1 - strbne r0, [r1], #1 - bne 9002b +9001: mov r0, #0 load_regs .popsection |