xtensa: complete ptrace handling of register windows
Compute WindowBase and WindowMask registers correctly on ptrace calls.
Work done earlier by Maxim, Christian and Marc.
Signed-off-by: Marc Gauthier <marc@tensilica.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Chris Zankel <chris@zankel.net>
diff --git a/arch/xtensa/kernel/ptrace.c b/arch/xtensa/kernel/ptrace.c
index 61fb2e9..a8b0d57 100644
--- a/arch/xtensa/kernel/ptrace.c
+++ b/arch/xtensa/kernel/ptrace.c
@@ -53,9 +53,8 @@
{
struct pt_regs *regs = task_pt_regs(child);
xtensa_gregset_t __user *gregset = uregs;
- unsigned long wm = regs->wmask;
unsigned long wb = regs->windowbase;
- int live, i;
+ int i;
if (!access_ok(VERIFY_WRITE, uregs, sizeof(xtensa_gregset_t)))
return -EIO;
@@ -68,12 +67,9 @@
__put_user(regs->windowstart, &gregset->windowstart);
__put_user(regs->windowbase, &gregset->windowbase);
- live = (wm & 2) ? 4 : (wm & 4) ? 8 : (wm & 8) ? 12 : 16;
-
- for (i = 0; i < live; i++)
- __put_user(regs->areg[i],gregset->a+((wb*4+i)%XCHAL_NUM_AREGS));
- for (i = XCHAL_NUM_AREGS - (wm >> 4) * 4; i < XCHAL_NUM_AREGS; i++)
- __put_user(regs->areg[i],gregset->a+((wb*4+i)%XCHAL_NUM_AREGS));
+ for (i = 0; i < XCHAL_NUM_AREGS; i++)
+ __put_user(regs->areg[i],
+ gregset->a + ((wb * 4 + i) % XCHAL_NUM_AREGS));
return 0;
}
@@ -84,7 +80,7 @@
xtensa_gregset_t *gregset = uregs;
const unsigned long ps_mask = PS_CALLINC_MASK | PS_OWB_MASK;
unsigned long ps;
- unsigned long wb;
+ unsigned long wb, ws;
if (!access_ok(VERIFY_WRITE, uregs, sizeof(xtensa_gregset_t)))
return -EIO;
@@ -94,7 +90,7 @@
__get_user(regs->lbeg, &gregset->lbeg);
__get_user(regs->lend, &gregset->lend);
__get_user(regs->lcount, &gregset->lcount);
- __get_user(regs->windowstart, &gregset->windowstart);
+ __get_user(ws, &gregset->windowstart);
__get_user(wb, &gregset->windowbase);
regs->ps = (regs->ps & ~ps_mask) | (ps & ps_mask) | (1 << PS_EXCM_BIT);
@@ -102,13 +98,24 @@
if (wb >= XCHAL_NUM_AREGS / 4)
return -EFAULT;
- regs->windowbase = wb;
+ if (wb != regs->windowbase || ws != regs->windowstart) {
+ unsigned long rotws, wmask;
+
+ rotws = (((ws | (ws << WSBITS)) >> wb) &
+ ((1 << WSBITS) - 1)) & ~1;
+ wmask = ((rotws ? WSBITS + 1 - ffs(rotws) : 0) << 4) |
+ (rotws & 0xF) | 1;
+ regs->windowbase = wb;
+ regs->windowstart = ws;
+ regs->wmask = wmask;
+ }
if (wb != 0 && __copy_from_user(regs->areg + XCHAL_NUM_AREGS - wb * 4,
- gregset->a, wb * 16))
+ gregset->a, wb * 16))
return -EFAULT;
- if (__copy_from_user(regs->areg, gregset->a + wb*4, (WSBITS-wb) * 16))
+ if (__copy_from_user(regs->areg, gregset->a + wb * 4,
+ (WSBITS - wb) * 16))
return -EFAULT;
return 0;