lkml.org 
[lkml]   [2021]   [Nov]   [10]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    Subject[PATCH v2 11/23] x86,xen: Remove .fixup usage
    Employ the fancy new EX_TYPE_IMM_REG to store -EFAULT in the return
    register and use this to remove some Xen .fixup usage.

    All callers of these functions only test for 0 return, so the actual
    return value change from -1 to -EFAULT is immaterial.

    Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
    ---
    arch/x86/include/asm/xen/page.h | 14 +++-----------
    1 file changed, 3 insertions(+), 11 deletions(-)

    --- a/arch/x86/include/asm/xen/page.h
    +++ b/arch/x86/include/asm/xen/page.h
    @@ -96,11 +96,7 @@ static inline int xen_safe_write_ulong(u

    asm volatile("1: mov %[val], %[ptr]\n"
    "2:\n"
    - ".section .fixup, \"ax\"\n"
    - "3: sub $1, %[ret]\n"
    - " jmp 2b\n"
    - ".previous\n"
    - _ASM_EXTABLE(1b, 3b)
    + _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_EFAULT_REG, %[ret])
    : [ret] "+r" (ret), [ptr] "=m" (*addr)
    : [val] "r" (val));

    @@ -110,16 +106,12 @@ static inline int xen_safe_write_ulong(u
    static inline int xen_safe_read_ulong(const unsigned long *addr,
    unsigned long *val)
    {
    - int ret = 0;
    unsigned long rval = ~0ul;
    + int ret = 0;

    asm volatile("1: mov %[ptr], %[rval]\n"
    "2:\n"
    - ".section .fixup, \"ax\"\n"
    - "3: sub $1, %[ret]\n"
    - " jmp 2b\n"
    - ".previous\n"
    - _ASM_EXTABLE(1b, 3b)
    + _ASM_EXTABLE_TYPE_REG(1b, 2b, EX_TYPE_EFAUL_REG, %[ret])
    : [ret] "+r" (ret), [rval] "+r" (rval)
    : [ptr] "m" (*addr));
    *val = rval;

    \
     
     \ /
      Last update: 2021-11-10 11:17    [W:8.647 / U:0.356 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site