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authorJens Axboe <axboe@kernel.dk>2019-02-15 08:43:59 -0700
committerJens Axboe <axboe@kernel.dk>2019-02-15 08:43:59 -0700
commit6fb845f0e78de19eaaf6a2d351702474e44b6a9e (patch)
tree94c6474b38d8f59d8f0de0151053283812e456c6 /arch/x86/lib/iomem.c
parent56d18f62f556b80105e38e7975975cf7465aae3e (diff)
parentd13937116f1e82bf508a6325111b322c30c85eb9 (diff)
Merge tag 'v5.0-rc6' into for-5.1/block
Pull in 5.0-rc6 to avoid a dumb merge conflict with fs/iomap.c. This is needed since io_uring is now based on the block branch, to avoid a conflict between the multi-page bvecs and the bits of io_uring that touch the core block parts. * tag 'v5.0-rc6': (525 commits) Linux 5.0-rc6 x86/mm: Make set_pmd_at() paravirt aware MAINTAINERS: Update the ocores i2c bus driver maintainer, etc blk-mq: remove duplicated definition of blk_mq_freeze_queue Blk-iolatency: warn on negative inflight IO counter blk-iolatency: fix IO hang due to negative inflight counter MAINTAINERS: unify reference to xen-devel list x86/mm/cpa: Fix set_mce_nospec() futex: Handle early deadlock return correctly futex: Fix barrier comment net: dsa: b53: Fix for failure when irq is not defined in dt blktrace: Show requests without sector mips: cm: reprime error cause mips: loongson64: remove unreachable(), fix loongson_poweroff(). sit: check if IPv6 enabled before calling ip6_err_gen_icmpv6_unreach() geneve: should not call rt6_lookup() when ipv6 was disabled KVM: nVMX: unconditionally cancel preemption timer in free_nested (CVE-2019-7221) KVM: x86: work around leak of uninitialized stack contents (CVE-2019-7222) kvm: fix kvm_ioctl_create_device() reference counting (CVE-2019-6974) signal: Better detection of synchronous signals ...
Diffstat (limited to 'arch/x86/lib/iomem.c')
-rw-r--r--arch/x86/lib/iomem.c33
1 files changed, 30 insertions, 3 deletions
diff --git a/arch/x86/lib/iomem.c b/arch/x86/lib/iomem.c
index 66894675f3c8..df50451d94ef 100644
--- a/arch/x86/lib/iomem.c
+++ b/arch/x86/lib/iomem.c
@@ -2,8 +2,11 @@
#include <linux/module.h>
#include <linux/io.h>
+#define movs(type,to,from) \
+ asm volatile("movs" type:"=&D" (to), "=&S" (from):"0" (to), "1" (from):"memory")
+
/* Originally from i386/string.h */
-static __always_inline void __iomem_memcpy(void *to, const void *from, size_t n)
+static __always_inline void rep_movs(void *to, const void *from, size_t n)
{
unsigned long d0, d1, d2;
asm volatile("rep ; movsl\n\t"
@@ -21,13 +24,37 @@ static __always_inline void __iomem_memcpy(void *to, const void *from, size_t n)
void memcpy_fromio(void *to, const volatile void __iomem *from, size_t n)
{
- __iomem_memcpy(to, (const void *)from, n);
+ if (unlikely(!n))
+ return;
+
+ /* Align any unaligned source IO */
+ if (unlikely(1 & (unsigned long)from)) {
+ movs("b", to, from);
+ n--;
+ }
+ if (n > 1 && unlikely(2 & (unsigned long)from)) {
+ movs("w", to, from);
+ n-=2;
+ }
+ rep_movs(to, (const void *)from, n);
}
EXPORT_SYMBOL(memcpy_fromio);
void memcpy_toio(volatile void __iomem *to, const void *from, size_t n)
{
- __iomem_memcpy((void *)to, (const void *) from, n);
+ if (unlikely(!n))
+ return;
+
+ /* Align any unaligned destination IO */
+ if (unlikely(1 & (unsigned long)to)) {
+ movs("b", to, from);
+ n--;
+ }
+ if (n > 1 && unlikely(2 & (unsigned long)to)) {
+ movs("w", to, from);
+ n-=2;
+ }
+ rep_movs((void *)to, (const void *) from, n);
}
EXPORT_SYMBOL(memcpy_toio);