Page MenuHomeFreeBSD
Differential D54947 Diff 170737 sys/arm64/arm64/copyinout.S

Changeset View

Standalone View

View Options

sys/arm64/arm64/copyinout.S

Show First 20 Lines • Show All 59 Lines • ▼ Show 20 Lines
copyio_fault_nopcb: copyio_fault_nopcb:
mov x0, #EFAULT mov x0, #EFAULT
ret ret
END(copyio_fault) END(copyio_fault)
/* /*
* Copies from a kernel to user address * Copies from a kernel to user address
* *
* int copyout(const void *kaddr, void *udaddr, size_t len) * int copyout_std(const void *kaddr, void *udaddr, size_t len)
*/ */
ENTRY(copyout) ENTRY(copyout_std)
cbz x2, 1f cbz x2, 1f
check_user_access 1, 2, copyio_fault_nopcb check_user_access 1, 2, copyio_fault_nopcb
b copycommon b copycommon
1: mov x0, xzr /* return 0 */ 1: mov x0, xzr /* return 0 */
ret ret
END(copyout) END(copyout_std)
/* /*
* Copies from a kernel to user address
*
* int copyout_mops(const void *kaddr, void *udaddr, size_t len)
*/
ENTRY(copyout_mops)
cbz x2, 1f
check_user_access 1, 2, copyio_fault_nopcb
b copycommon_mops
andrewUnsubmitted
Not Done
Inline Actions

You can use cpyf*rt and cpyf*wt directly to implement copyin & copyout.

As they execute the load/store as unprivileged operations you will need to set the fault handler, but don't need to enable user access.

andrew: You can use `cpyf*rt` and `cpyf*wt` directly to implement copyin & copyout. As they execute…
1: mov x0, xzr /* return 0 */
ret
END(copyout_mops)
/*
* Copies from a user to kernel address * Copies from a user to kernel address
* *
* int copyin(const void *uaddr, void *kdaddr, size_t len) * int copyin_std(const void *uaddr, void *kdaddr, size_t len)
*/ */
ENTRY(copyin) ENTRY(copyin_std)
cbz x2, 1f cbz x2, 1f
check_user_access 0, 2, copyio_fault_nopcb check_user_access 0, 2, copyio_fault_nopcb
b copycommon b copycommon
1: mov x0, xzr /* return 0 */ 1: mov x0, xzr /* return 0 */
ret ret
END(copyin) END(copyin_std)
/* /*
* Copies from a user to kernel address
*
* int copyin_mops(const void *uaddr, void *kdaddr, size_t len)
*/
ENTRY(copyin_mops)
cbz x2, 1f
check_user_access 0, 2, copyio_fault_nopcb
b copycommon
1: mov x0, xzr /* return 0 */
ret
END(copyin_mops)
/*
* Copies a string from a user to kernel address * Copies a string from a user to kernel address
* *
* int copyinstr(const void *udaddr, void *kaddr, size_t len, size_t *done) * int copyinstr(const void *udaddr, void *kaddr, size_t len, size_t *done)
*/ */
ENTRY(copyinstr) ENTRY(copyinstr)
mov x5, xzr /* count = 0 */ mov x5, xzr /* count = 0 */
mov w4, #1 /* If zero return faulure */ mov w4, #1 /* If zero return faulure */
cbz x2, 3f /* If len == 0 then skip loop */ cbz x2, 3f /* If len == 0 then skip loop */
▲ Show 20 Lines • Show All 124 Lines • ▼ Show 20 Lines
ending: ending:
EXIT_USER_ACCESS_CHECK(w6, x7) EXIT_USER_ACCESS_CHECK(w6, x7)
SET_FAULT_HANDLER(xzr, x7) /* Clear the handler */ SET_FAULT_HANDLER(xzr, x7) /* Clear the handler */
mov x0, xzr /* return 0 */ mov x0, xzr /* return 0 */
ret ret
.size copycommon, . - copycommon .size copycommon, . - copycommon
/*
* Local helper (MOPS version)
*
* x0 - src pointer
* x1 - dst pointer
* x2 - size
* lr - the return address, so jump here instead of calling
*/
.text
.align 4
.local copycommon_mops
.type copycommon_mops,@function
copycommon_mops:
adr x6, copyio_fault /* Get the handler address */
SET_FAULT_HANDLER(x6, x7) /* Set the handler */
ENTER_USER_ACCESS(w6, x7)
.inst 0x19000441 /* cpyfp [x1]!, [x0]!, x2! */
.inst 0x19400441 /* cpyfm [x1]!, [x0]!, x2! */
.inst 0x19800441 /* cpyfe [x1]!, [x0]!, x2! */
EXIT_USER_ACCESS_CHECK(w6, x7)
SET_FAULT_HANDLER(xzr, x7) /* Clear the handler */
mov x0, xzr /* return 0 */
ret
.size copycommon_mops, . - copycommon_mops
GNU_PROPERTY_AARCH64_FEATURE_1_NOTE(GNU_PROPERTY_AARCH64_FEATURE_1_VAL) GNU_PROPERTY_AARCH64_FEATURE_1_NOTE(GNU_PROPERTY_AARCH64_FEATURE_1_VAL)