Commit 83c54070 authored by Nick Piggin's avatar Nick Piggin Committed by Linus Torvalds

mm: fault feedback #2

This patch completes Linus's wish that the fault return codes be made into
bit flags, which I agree makes everything nicer.  This requires requires
all handle_mm_fault callers to be modified (possibly the modifications
should go further and do things like fault accounting in handle_mm_fault --
however that would be for another patch).

[akpm@linux-foundation.org: fix alpha build]
[akpm@linux-foundation.org: fix s390 build]
[akpm@linux-foundation.org: fix sparc build]
[akpm@linux-foundation.org: fix sparc64 build]
[akpm@linux-foundation.org: fix ia64 build]
Signed-off-by: default avatarNick Piggin <npiggin@suse.de>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Ian Molton <spyro@f2s.com>
Cc: Bryan Wu <bryan.wu@analog.com>
Cc: Mikael Starvik <starvik@axis.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Hirokazu Takata <takata@linux-m32r.org>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Roman Zippel <zippel@linux-m68k.org>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Matthew Wilcox <willy@debian.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Kazumoto Kojima <kkojima@rr.iij4u.or.jp>
Cc: Richard Curnow <rc@rc0.org.uk>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
Cc: Miles Bader <uclinux-v850@lsi.nec.co.jp>
Cc: Chris Zankel <chris@zankel.net>
Acked-by: default avatarKyle McMartin <kyle@mcmartin.ca>
Acked-by: default avatarHaavard Skinnemoen <hskinnemoen@atmel.com>
Acked-by: default avatarRalf Baechle <ralf@linux-mips.org>
Acked-by: default avatarAndi Kleen <ak@muc.de>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
[ Still apparently needs some ARM and PPC loving - Linus ]
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent d0217ac0
......@@ -148,21 +148,17 @@ do_page_fault(unsigned long address, unsigned long mmcsr,
the fault. */
fault = handle_mm_fault(mm, vma, address, cause > 0);
up_read(&mm->mmap_sem);
switch (fault) {
case VM_FAULT_MINOR:
current->min_flt++;
break;
case VM_FAULT_MAJOR:
current->maj_flt++;
break;
case VM_FAULT_SIGBUS:
goto do_sigbus;
case VM_FAULT_OOM:
goto out_of_memory;
default:
if (unlikely(fault & VM_FAULT_ERROR)) {
if (fault & VM_FAULT_OOM)
goto out_of_memory;
else if (fault & VM_FAULT_SIGBUS)
goto do_sigbus;
BUG();
}
if (fault & VM_FAULT_MAJOR)
current->maj_flt++;
else
current->min_flt++;
return;
/* Something tried to access memory that isn't in our memory map.
......
......@@ -183,20 +183,20 @@ good_area:
*/
survive:
fault = handle_mm_fault(mm, vma, addr & PAGE_MASK, fsr & (1 << 11));
/*
* Handle the "normal" cases first - successful and sigbus
*/
switch (fault) {
case VM_FAULT_MAJOR:
if (unlikely(fault & VM_FAULT_ERROR)) {
if (fault & VM_FAULT_OOM)
goto out_of_memory;
else if (fault & VM_FAULT_SIGBUS)
return fault;
BUG();
}
if (fault & VM_FAULT_MAJOR)
tsk->maj_flt++;
return fault;
case VM_FAULT_MINOR:
else
tsk->min_flt++;
case VM_FAULT_SIGBUS:
return fault;
}
return fault;
out_of_memory:
if (!is_init(tsk))
goto out;
......@@ -249,7 +249,7 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
/*
* Handle the "normal" case first - VM_FAULT_MAJOR / VM_FAULT_MINOR
*/
if (fault >= VM_FAULT_MINOR)
if (likely(!(fault & VM_FAULT_ERROR)))
return 0;
/*
......@@ -259,8 +259,7 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
if (!user_mode(regs))
goto no_context;
switch (fault) {
case VM_FAULT_OOM:
if (fault & VM_FAULT_OOM) {
/*
* We ran out of memory, or some other thing
* happened to us that made us unable to handle
......@@ -269,17 +268,15 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
printk("VM: killing process %s\n", tsk->comm);
do_exit(SIGKILL);
return 0;
case VM_FAULT_SIGBUS:
}
if (fault & VM_FAULT_SIGBUS) {
/*
* We had some memory, but were unable to
* successfully fix up this page fault.
*/
sig = SIGBUS;
code = BUS_ADRERR;
break;
default:
} else {
/*
* Something tried to access memory that
* isn't in our memory map..
......@@ -287,7 +284,6 @@ do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
sig = SIGSEGV;
code = fault == VM_FAULT_BADACCESS ?
SEGV_ACCERR : SEGV_MAPERR;
break;
}
__do_user_fault(tsk, addr, fsr, sig, code, regs);
......
......@@ -170,20 +170,20 @@ good_area:
*/
survive:
fault = handle_mm_fault(mm, vma, addr & PAGE_MASK, DO_COW(fsr));
/*
* Handle the "normal" cases first - successful and sigbus
*/
switch (fault) {
case VM_FAULT_MAJOR:
if (unlikely(fault & VM_FAULT_ERROR)) {
if (fault & VM_FAULT_OOM)
goto out_of_memory;
else if (fault & VM_FAULT_SIGBUS)
return fault;
BUG();
}
if (fault & VM_FAULT_MAJOR)
tsk->maj_flt++;
return fault;
case VM_FAULT_MINOR:
else
tsk->min_flt++;
case VM_FAULT_SIGBUS:
return fault;
}
return fault;
out_of_memory:
fault = -3; /* out of memory */
if (!is_init(tsk))
goto out;
......@@ -225,13 +225,11 @@ int do_page_fault(unsigned long addr, unsigned int fsr, struct pt_regs *regs)
/*
* Handle the "normal" case first
*/
switch (fault) {
case VM_FAULT_MINOR:
case VM_FAULT_MAJOR:
if (likely(!(fault & VM_FAULT_ERROR)))
return 0;
case VM_FAULT_SIGBUS:
if (fault & VM_FAULT_SIGBUS)
goto do_sigbus;
}
/* else VM_FAULT_OOM */
/*
* If we are in kernel mode at this point, we
......
......@@ -64,6 +64,7 @@ asmlinkage void do_page_fault(unsigned long ecr, struct pt_regs *regs)
int writeaccess;
long signr;
int code;
int fault;
if (notify_page_fault(regs, ecr))
return;
......@@ -132,20 +133,18 @@ good_area:
* fault.
*/
survive:
switch (handle_mm_fault(mm, vma, address, writeaccess)) {
case VM_FAULT_MINOR:
tsk->min_flt++;
break;
case VM_FAULT_MAJOR:
tsk->maj_flt++;
break;
case VM_FAULT_SIGBUS:
goto do_sigbus;
case VM_FAULT_OOM:
goto out_of_memory;
default:
fault = handle_mm_fault(mm, vma, address, writeaccess);
if (unlikely(fault & VM_FAULT_ERROR)) {
if (fault & VM_FAULT_OOM)
goto out_of_memory;
else if (fault & VM_FAULT_SIGBUS)
goto do_sigbus;
BUG();
}
if (fault & VM_FAULT_MAJOR)
tsk->maj_flt++;
else
tsk->min_flt++;
up_read(&mm->mmap_sem);
return;
......
......@@ -179,6 +179,7 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
struct mm_struct *mm;
struct vm_area_struct * vma;
siginfo_t info;
int fault;
D(printk("Page fault for %lX on %X at %lX, prot %d write %d\n",
address, smp_processor_id(), instruction_pointer(regs),
......@@ -283,18 +284,18 @@ do_page_fault(unsigned long address, struct pt_regs *regs,
* the fault.
*/
switch (handle_mm_fault(mm, vma, address, writeaccess & 1)) {
case VM_FAULT_MINOR:
tsk->min_flt++;
break;
case VM_FAULT_MAJOR:
tsk->maj_flt++;
break;
case VM_FAULT_SIGBUS:
goto do_sigbus;
default:
goto out_of_memory;
fault = handle_mm_fault(mm, vma, address, writeaccess & 1);
if (unlikely(fault & VM_FAULT_ERROR)) {
if (fault & VM_FAULT_OOM)
goto out_of_memory;
else if (fault & VM_FAULT_SIGBUS)
goto do_sigbus;
BUG();
}
if (fault & VM_FAULT_MAJOR)
tsk->maj_flt++;
else
tsk->min_flt++;
up_read(&mm->mmap_sem);
return;
......
......@@ -40,6 +40,7 @@ asmlinkage void do_page_fault(int datammu, unsigned long esr0, unsigned long ear
pud_t *pue;
pte_t *pte;
int write;
int fault;
#if 0
const char *atxc[16] = {
......@@ -162,18 +163,18 @@ asmlinkage void do_page_fault(int datammu, unsigned long esr0, unsigned long ear
* make sure we exit gracefully rather than endlessly redo
* the fault.
*/
switch (handle_mm_fault(mm, vma, ear0, write)) {
case VM_FAULT_MINOR:
current->min_flt++;
break;
case VM_FAULT_MAJOR:
current->maj_flt++;
break;
case VM_FAULT_SIGBUS:
goto do_sigbus;
default:
goto out_of_memory;
fault = handle_mm_fault(mm, vma, ear0, write);
if (unlikely(fault & VM_FAULT_ERROR)) {
if (fault & VM_FAULT_OOM)
goto out_of_memory;
else if (fault & VM_FAULT_SIGBUS)
goto do_sigbus;
BUG();
}
if (fault & VM_FAULT_MAJOR)
current->maj_flt++;
else
current->min_flt++;
up_read(&mm->mmap_sem);
return;
......
......@@ -303,6 +303,7 @@ fastcall void __kprobes do_page_fault(struct pt_regs *regs,
struct vm_area_struct * vma;
unsigned long address;
int write, si_code;
int fault;
/* get the address */
address = read_cr2();
......@@ -422,20 +423,18 @@ good_area:
* make sure we exit gracefully rather than endlessly redo
* the fault.
*/
switch (handle_mm_fault(mm, vma, address, write)) {
case VM_FAULT_MINOR:
tsk->min_flt++;
break;
case VM_FAULT_MAJOR:
tsk->maj_flt++;
break;
case VM_FAULT_SIGBUS:
goto do_sigbus;
case VM_FAULT_OOM:
fault = handle_mm_fault(mm, vma, address, write);
if (unlikely(fault & VM_FAULT_ERROR)) {
if (fault & VM_FAULT_OOM)
goto out_of_memory;
default:
BUG();
else if (fault & VM_FAULT_SIGBUS)
goto do_sigbus;
BUG();
}
if (fault & VM_FAULT_MAJOR)
tsk->maj_flt++;
else
tsk->min_flt++;
/*
* Did it hit the DOS screen memory VA from vm86 mode?
......
......@@ -80,6 +80,7 @@ ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *re
struct mm_struct *mm = current->mm;
struct siginfo si;
unsigned long mask;
int fault;
/* mmap_sem is performance critical.... */
prefetchw(&mm->mmap_sem);
......@@ -147,26 +148,25 @@ ia64_do_page_fault (unsigned long address, unsigned long isr, struct pt_regs *re
* sure we exit gracefully rather than endlessly redo the
* fault.
*/
switch (handle_mm_fault(mm, vma, address, (mask & VM_WRITE) != 0)) {
case VM_FAULT_MINOR:
++current->min_flt;
break;
case VM_FAULT_MAJOR:
++current->maj_flt;
break;
case VM_FAULT_SIGBUS:
fault = handle_mm_fault(mm, vma, address, (mask & VM_WRITE) != 0);
if (unlikely(fault & VM_FAULT_ERROR)) {
/*
* We ran out of memory, or some other thing happened
* to us that made us unable to handle the page fault
* gracefully.
*/
signal = SIGBUS;
goto bad_area;
case VM_FAULT_OOM:
goto out_of_memory;
default:
if (fault & VM_FAULT_OOM) {
goto out_of_memory;
} else if (fault & VM_FAULT_SIGBUS) {
signal = SIGBUS;
goto bad_area;
}
BUG();
}
if (fault & VM_FAULT_MAJOR)
current->maj_flt++;
else
current->min_flt++;
up_read(&mm->mmap_sem);
return;
......
......@@ -80,6 +80,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long error_code,
struct vm_area_struct * vma;
unsigned long page, addr;
int write;
int fault;
siginfo_t info;
/*
......@@ -195,20 +196,18 @@ survive:
*/
addr = (address & PAGE_MASK);
set_thread_fault_code(error_code);
switch (handle_mm_fault(mm, vma, addr, write)) {
case VM_FAULT_MINOR:
tsk->min_flt++;
break;
case VM_FAULT_MAJOR:
tsk->maj_flt++;
break;
case VM_FAULT_SIGBUS:
goto do_sigbus;
case VM_FAULT_OOM:
fault = handle_mm_fault(mm, vma, addr, write);
if (unlikely(fault & VM_FAULT_ERROR)) {
if (fault & VM_FAULT_OOM)
goto out_of_memory;
default:
BUG();
else if (fault & VM_FAULT_SIGBUS)
goto do_sigbus;
BUG();
}
if (fault & VM_FAULT_MAJOR)
tsk->maj_flt++;
else
tsk->min_flt++;
set_thread_fault_code(0);
up_read(&mm->mmap_sem);
return;
......
......@@ -159,18 +159,17 @@ good_area:
#ifdef DEBUG
printk("handle_mm_fault returns %d\n",fault);
#endif
switch (fault) {
case VM_FAULT_MINOR:
current->min_flt++;
break;
case VM_FAULT_MAJOR:
current->maj_flt++;
break;
case VM_FAULT_SIGBUS:
goto bus_err;
default:
goto out_of_memory;
if (unlikely(fault & VM_FAULT_ERROR)) {
if (fault & VM_FAULT_OOM)
goto out_of_memory;
else if (fault & VM_FAULT_SIGBUS)
goto bus_err;
BUG();
}
if (fault & VM_FAULT_MAJOR)
current->maj_flt++;
else
current->min_flt++;
up_read(&mm->mmap_sem);
return 0;
......
......@@ -39,6 +39,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long write,
struct mm_struct *mm = tsk->mm;
const int field = sizeof(unsigned long) * 2;
siginfo_t info;
int fault;
#if 0
printk("Cpu%d[%s:%d:%0*lx:%ld:%0*lx]\n", raw_smp_processor_id(),
......@@ -102,20 +103,18 @@ survive:
* make sure we exit gracefully rather than endlessly redo
* the fault.
*/
switch (handle_mm_fault(mm, vma, address, write)) {
case VM_FAULT_MINOR:
tsk->min_flt++;
break;
case VM_FAULT_MAJOR:
tsk->maj_flt++;
break;
case VM_FAULT_SIGBUS:
goto do_sigbus;
case VM_FAULT_OOM:
goto out_of_memory;
default:
fault = handle_mm_fault(mm, vma, address, write);
if (unlikely(fault & VM_FAULT_ERROR)) {
if (fault & VM_FAULT_OOM)
goto out_of_memory;
else if (fault & VM_FAULT_SIGBUS)
goto do_sigbus;
BUG();
}
if (fault & VM_FAULT_MAJOR)
tsk->maj_flt++;
else
tsk->min_flt++;
up_read(&mm->mmap_sem);
return;
......
......@@ -147,6 +147,7 @@ void do_page_fault(struct pt_regs *regs, unsigned long code,
struct mm_struct *mm = tsk->mm;
const struct exception_table_entry *fix;
unsigned long acc_type;
int fault;
if (in_atomic() || !mm)
goto no_context;
......@@ -173,23 +174,23 @@ good_area:
* fault.
*/
switch (handle_mm_fault(mm, vma, address, (acc_type & VM_WRITE) != 0)) {
case VM_FAULT_MINOR:
++current->min_flt;
break;
case VM_FAULT_MAJOR:
++current->maj_flt;
break;
case VM_FAULT_SIGBUS:
fault = handle_mm_fault(mm, vma, address, (acc_type & VM_WRITE) != 0);
if (unlikely(fault & VM_FAULT_ERROR)) {
/*
* We hit a shared mapping outside of the file, or some
* other thing happened to us that made us unable to
* handle the page fault gracefully.
*/
goto bad_area;
default:
goto out_of_memory;
if (fault & VM_FAULT_OOM)
goto out_of_memory;
else if (fault & VM_FAULT_SIGBUS)
goto bad_area;
BUG();
}
if (fault & VM_FAULT_MAJOR)
current->maj_flt++;
else
current->min_flt++;
up_read(&mm->mmap_sem);
return;
......
......@@ -145,7 +145,7 @@ int __kprobes do_page_fault(struct pt_regs *regs, unsigned long address,
struct mm_struct *mm = current->mm;
siginfo_t info;
int code = SEGV_MAPERR;
int is_write = 0;
int is_write = 0, ret;
int trap = TRAP(regs);
int is_exec = trap == 0x400;
......@@ -330,22 +330,18 @@ good_area:
* the fault.
*/
survive:
switch (handle_mm_fault(mm, vma, address, is_write)) {
case VM_FAULT_MINOR:
current->min_flt++;
break;
case VM_FAULT_MAJOR:
current->maj_flt++;
break;
case VM_FAULT_SIGBUS:
goto do_sigbus;
case VM_FAULT_OOM:
goto out_of_memory;
default:
ret = handle_mm_fault(mm, vma, address, is_write);
if (unlikely(ret & VM_FAULT_ERROR)) {
if (ret & VM_FAULT_OOM)
goto out_of_memory;
else if (ret & VM_FAULT_SIGBUS)
goto do_sigbus;
BUG();
}
if (ret & VM_FAULT_MAJOR)
current->maj_flt++;
else
current->min_flt++;
up_read(&mm->mmap_sem);
return 0;
......
......@@ -74,23 +74,21 @@ good_area:
goto bad_area;
}
ret = 0;
*flt = handle_mm_fault(mm, vma, ea, is_write);
switch (*flt) {
case VM_FAULT_MINOR:
current->min_flt++;
break;
case VM_FAULT_MAJOR:
current->maj_flt++;
break;
case VM_FAULT_SIGBUS:
ret = -EFAULT;
goto bad_area;
case VM_FAULT_OOM:
ret = -ENOMEM;
goto bad_area;
default:
fault = handle_mm_fault(mm, vma, ea, is_write);
if (unlikely(fault & VM_FAULT_ERROR)) {
if (fault & VM_FAULT_OOM) {
ret = -ENOMEM;
goto bad_area;
} else if (fault & VM_FAULT_SIGBUS) {
ret = -EFAULT;
goto bad_area;
}
BUG();
}
if (fault & VM_FAULT_MAJOR)
current->maj_flt++;
else
current->min_flt++;
up_read(&mm->mmap_sem);
return ret;
......
......@@ -96,6 +96,7 @@ int do_page_fault(struct pt_regs *regs, unsigned long address,
struct mm_struct *mm = current->mm;
siginfo_t info;
int code = SEGV_MAPERR;
int fault;
#if defined(CONFIG_4xx) || defined (CONFIG_BOOKE)
int is_write = error_code & ESR_DST;
#else
......@@ -249,20 +250,18 @@ good_area:
* the fault.
*/
survive:
switch (handle_mm_fault(mm, vma, address, is_write)) {
case VM_FAULT_MINOR:
current->min_flt++;
break;
case VM_FAULT_MAJOR:
current->maj_flt++;
break;
case VM_FAULT_SIGBUS:
goto do_sigbus;
case VM_FAULT_OOM:
goto out_of_memory;
default:
fault = handle_mm_fault(mm, vma, address, is_write);
if (unlikely(fault & VM_FAULT_ERROR)) {
if (fault & VM_FAULT_OOM)
goto out_of_memory;
else if (fault & VM_FAULT_SIGBUS)
goto do_sigbus;
BUG();
}
if (fault & VM_FAULT_MAJOR)
current->maj_flt++;
else
current->min_flt++;
up_read(&mm->mmap_sem);
/*
......
......@@ -20,6 +20,7 @@ static int __handle_fault(struct mm_struct *mm, unsigned long address,
{
struct vm_area_struct *vma;
int ret = -EFAULT;
int fault;
if (in_atomic())
return ret;
......@@ -44,20 +45,18 @@ static int __handle_fault(struct mm_struct *mm, unsigned long address,
}
survive:
switch (handle_mm_fault(mm, vma, address, write_access)) {
case VM_FAULT_MINOR: