mm: fault feedback #2
Nick Piggin [Thu, 19 Jul 2007 08:47:05 +0000 (01:47 -0700)]
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: Nick 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: Kyle McMartin <kyle@mcmartin.ca>
Acked-by: Haavard Skinnemoen <hskinnemoen@atmel.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Acked-by: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Still apparently needs some ARM and PPC loving - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

32 files changed:
arch/alpha/mm/fault.c
arch/arm/mm/fault.c
arch/arm26/mm/fault.c
arch/avr32/mm/fault.c
arch/cris/mm/fault.c
arch/frv/mm/fault.c
arch/i386/mm/fault.c
arch/ia64/mm/fault.c
arch/m32r/mm/fault.c
arch/m68k/mm/fault.c
arch/mips/mm/fault.c
arch/parisc/mm/fault.c
arch/powerpc/mm/fault.c
arch/powerpc/platforms/cell/spufs/fault.c
arch/ppc/mm/fault.c
arch/s390/lib/uaccess_pt.c
arch/s390/mm/fault.c
arch/sh/mm/fault.c
arch/sh64/mm/fault.c
arch/sparc/mm/fault.c
arch/sparc64/mm/fault.c
arch/um/kernel/trap.c
arch/x86_64/mm/fault.c
arch/xtensa/mm/fault.c
fs/gfs2/ops_vm.c
include/linux/mm.h
kernel/futex.c
mm/filemap.c
mm/filemap_xip.c
mm/hugetlb.c
mm/memory.c
mm/shmem.c

index f586279..a0e18da 100644 (file)
@@ -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.
index 75d4914..c04124a 100644 (file)
@@ -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);
index 93c0cee..dec638a 100644 (file)
@@ -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
index 4b24952..ae2d2c5 100644 (file)
@@ -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;
index c73e91f..8672ab7 100644 (file)
@@ -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;
index 3f12296..6798fa0 100644 (file)
@@ -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;
index 1ecb3e4..e92a101 100644 (file)
@@ -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?
index b87f785..73ccb60 100644 (file)
@@ -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;
 
index f3935ba..676a1c4 100644 (file)
@@ -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;
index 2adbeb1..578b48f 100644 (file)
@@ -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;
index 7ebea33..521771b 100644 (file)
@@ -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;
index f6f6755..7899ab8 100644 (file)
@@ -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;
 
index 0ece513..3767211 100644 (file)
@@ -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;
 
index e064d0c..07f88de 100644 (file)
@@ -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;
 
index 465f451..b98244e 100644 (file)
@@ -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);
        /*
index 6318167..60604b2 100644 (file)
@@ -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:
-               current->min_flt++;
-               break;
-       case VM_FAULT_MAJOR:
-               current->maj_flt++;
-               break;
-       case VM_FAULT_SIGBUS:
-               goto out_sigbus;
-       case VM_FAULT_OOM:
-               goto out_of_memory;
-       default:
+       fault = handle_mm_fault(mm, vma, address, write_access);
+       if (unlikely(fault & VM_FAULT_ERROR)) {
+               if (fault & VM_FAULT_OOM)
+                       goto out_of_memory;
+               else if (fault & VM_FAULT_SIGBUS)
+                       goto out_sigbus;
                BUG();
        }
+       if (fault & VM_FAULT_MAJOR)
+               current->maj_flt++;
+       else
+               current->min_flt++;
        ret = 0;
 out:
        up_read(&mm->mmap_sem);
index d855cdb..5405519 100644 (file)
@@ -307,6 +307,7 @@ do_exception(struct pt_regs *regs, unsigned long error_code, int write)
        unsigned long address;
        int space;
        int si_code;
+       int fault;
 
        if (notify_page_fault(regs, error_code))
                return;
@@ -377,23 +378,22 @@ 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:
-               do_sigbus(regs, error_code, address);
-               return;
-       case VM_FAULT_OOM:
-               if (do_out_of_memory(regs, error_code, address))
-                       goto survive;
-               return;
-       default:
+       fault = handle_mm_fault(mm, vma, address, write);
+       if (unlikely(fault & VM_FAULT_ERROR)) {
+               if (fault & VM_FAULT_OOM) {
+                       if (do_out_of_memory(regs, error_code, address))
+                               goto survive;
+                       return;
+               } else if (fault & VM_FAULT_SIGBUS) {
+                       do_sigbus(regs, error_code, address);
+                       return;
+               }
                BUG();
        }
+       if (fault & VM_FAULT_MAJOR)
+               tsk->maj_flt++;
+       else
+               tsk->min_flt++;
 
         up_read(&mm->mmap_sem);
        /*
index 0b3eaf6..964c676 100644 (file)
@@ -33,6 +33,7 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
        struct mm_struct *mm;
        struct vm_area_struct * vma;
        int si_code;
+       int fault;
        siginfo_t info;
 
        trace_hardirqs_on();
@@ -124,20 +125,18 @@ good_area:
         * the 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:
+       fault = handle_mm_fault(mm, vma, address, writeaccess);
+       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++;
 
        up_read(&mm->mmap_sem);
        return;
index 3cd93ba..0d069d8 100644 (file)
@@ -127,6 +127,7 @@ asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long writeaccess,
        struct vm_area_struct * vma;
        const struct exception_table_entry *fixup;
        pte_t *pte;
+       int fault;
 
 #if defined(CONFIG_SH64_PROC_TLB)
         ++calls_to_do_slow_page_fault;
@@ -221,18 +222,19 @@ good_area:
         * the 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;
-       default:
-               goto out_of_memory;
+       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++;
+
        /* If we get here, the page fault has been handled.  Do the TLB refill
           now from the newly-setup PTE, to avoid having to fault again right
           away on the same instruction. */
index c348336..50747fe 100644 (file)
@@ -226,6 +226,7 @@ asmlinkage void do_sparc_fault(struct pt_regs *regs, int text_fault, int write,
        unsigned long g2;
        siginfo_t info;
        int from_user = !(regs->psr & PSR_PS);
+       int fault;
 
        if(text_fault)
                address = regs->pc;
@@ -289,19 +290,18 @@ good_area:
         * make sure we exit gracefully rather than endlessly redo
         * the fault.
         */
-       switch (handle_mm_fault(mm, vma, address, write)) {
-       case VM_FAULT_SIGBUS:
-               goto do_sigbus;
-       case VM_FAULT_OOM:
-               goto out_of_memory;
-       case VM_FAULT_MAJOR:
+       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)
                current->maj_flt++;
-               break;
-       case VM_FAULT_MINOR:
-       default:
+       else
                current->min_flt++;
-               break;
-       }
        up_read(&mm->mmap_sem);
        return;
 
index b582024..17123e9 100644 (file)
@@ -278,7 +278,7 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs)
        struct mm_struct *mm = current->mm;
        struct vm_area_struct *vma;
        unsigned int insn = 0;
-       int si_code, fault_code;
+       int si_code, fault_code, fault;
        unsigned long address, mm_rss;
 
        fault_code = get_thread_fault_code();
@@ -415,20 +415,18 @@ good_area:
                        goto bad_area;
        }
 
-       switch (handle_mm_fault(mm, vma, address, (fault_code & FAULT_CODE_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, (fault_code & FAULT_CODE_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);
 
index abab90c..3850d53 100644 (file)
@@ -76,23 +76,24 @@ good_area:
                goto out;
 
        do {
+               int 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:
-                       err = -EACCES;
-                       goto out;
-               case VM_FAULT_OOM:
-                       err = -ENOMEM;
-                       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) {
+                               err = -ENOMEM;
+                               goto out_of_memory;
+                       } else if (fault & VM_FAULT_SIGBUS) {
+                               err = -EACCES;
+                               goto out;
+                       }
                        BUG();
                }
+               if (fault & VM_FAULT_MAJOR)
+                       current->maj_flt++;
+               else
+                       current->min_flt++;
+
                pgd = pgd_offset(mm, address);
                pud = pud_offset(pgd, address);
                pmd = pmd_offset(pud, address);
index 635e58d..84f1172 100644 (file)
@@ -317,7 +317,7 @@ asmlinkage void __kprobes do_page_fault(struct pt_regs *regs,
        struct vm_area_struct * vma;
        unsigned long address;
        const struct exception_table_entry *fixup;
-       int write;
+       int write, fault;
        unsigned long flags;
        siginfo_t info;
 
@@ -450,19 +450,18 @@ 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;
-       default:
-               goto out_of_memory;
+       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;
 
index 3dc6f2f..1600406 100644 (file)
@@ -41,6 +41,7 @@ void do_page_fault(struct pt_regs *regs)
        siginfo_t info;
 
        int is_write, is_exec;
+       int fault;
 
        info.si_code = SEGV_MAPERR;
 
@@ -102,20 +103,18 @@ 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);
        return;
index dc287d2..927d739 100644 (file)
@@ -112,7 +112,7 @@ static int gfs2_sharewrite_fault(struct vm_area_struct *vma,
        struct gfs2_holder i_gh;
        int alloc_required;
        int error;
-       int ret = VM_FAULT_MINOR;
+       int ret = 0;
 
        error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh);
        if (error)
@@ -132,14 +132,19 @@ static int gfs2_sharewrite_fault(struct vm_area_struct *vma,
        set_bit(GFF_EXLOCK, &gf->f_flags);
        ret = filemap_fault(vma, vmf);
        clear_bit(GFF_EXLOCK, &gf->f_flags);
-       if (ret & (VM_FAULT_ERROR | FAULT_RET_NOPAGE))
+       if (ret & VM_FAULT_ERROR)
                goto out_unlock;
 
        if (alloc_required) {
                /* XXX: do we need to drop page lock around alloc_page_backing?*/
                error = alloc_page_backing(ip, vmf->page);
                if (error) {
-                       if (ret & FAULT_RET_LOCKED)
+                       /*
+                        * VM_FAULT_LOCKED should always be the case for
+                        * filemap_fault, but it may not be in a future
+                        * implementation.
+                        */
+                       if (ret & VM_FAULT_LOCKED)
                                unlock_page(vmf->page);
                        page_cache_release(vmf->page);
                        ret = VM_FAULT_OOM;
index ff0b884..f8e12b3 100644 (file)
@@ -196,25 +196,10 @@ extern pgprot_t protection_map[16];
 #define FAULT_FLAG_NONLINEAR   0x02    /* Fault was via a nonlinear mapping */
 
 
-#define FAULT_RET_NOPAGE       0x0100  /* ->fault did not return a page. This
-                                        * can be used if the handler installs
-                                        * their own pte.
-                                        */
-#define FAULT_RET_LOCKED       0x0200  /* ->fault locked the page, caller must
-                                        * unlock after installing the mapping.
-                                        * This is used by pagecache in
-                                        * particular, where the page lock is
-                                        * used to synchronise against truncate
-                                        * and invalidate. Mutually exclusive
-                                        * with FAULT_RET_NOPAGE.
-                                        */
-
 /*
  * vm_fault is filled by the the pagefault handler and passed to the vma's
- * ->fault function. The vma's ->fault is responsible for returning the
- * VM_FAULT_xxx type which occupies the lowest byte of the return code, ORed
- * with FAULT_RET_ flags that occupy the next byte and give details about
- * how the fault was handled.
+ * ->fault function. The vma's ->fault is responsible for returning a bitmask
+ * of VM_FAULT_xxx flags that give details about how the fault was handled.
  *
  * pgoff should be used in favour of virtual_address, if possible. If pgoff
  * is used, one may set VM_CAN_NONLINEAR in the vma->vm_flags to get nonlinear
@@ -226,9 +211,9 @@ struct vm_fault {
        void __user *virtual_address;   /* Faulting virtual address */
 
        struct page *page;              /* ->fault handlers should return a
-                                        * page here, unless FAULT_RET_NOPAGE
+                                        * page here, unless VM_FAULT_NOPAGE
                                         * is set (which is also implied by
-                                        * VM_FAULT_OOM or SIGBUS).
+                                        * VM_FAULT_ERROR).
                                         */
 };
 
@@ -712,26 +697,17 @@ static inline int page_mapped(struct page *page)
  * just gets major/minor fault counters bumped up.
  */
 
-/*
- * VM_FAULT_ERROR is set for the error cases, to make some tests simpler.
- */
-#define VM_FAULT_ERROR 0x20
+#define VM_FAULT_MINOR 0 /* For backwards compat. Remove me quickly. */
 
-#define VM_FAULT_OOM   (0x00 | VM_FAULT_ERROR)
-#define VM_FAULT_SIGBUS        (0x01 | VM_FAULT_ERROR)
-#define VM_FAULT_MINOR 0x02
-#define VM_FAULT_MAJOR 0x03
+#define VM_FAULT_OOM   0x0001
+#define VM_FAULT_SIGBUS        0x0002
+#define VM_FAULT_MAJOR 0x0004
+#define VM_FAULT_WRITE 0x0008  /* Special case for get_user_pages */
 
-/* 
- * Special case for get_user_pages.
- * Must be in a distinct bit from the above VM_FAULT_ flags.
- */
-#define VM_FAULT_WRITE 0x10
+#define VM_FAULT_NOPAGE        0x0100  /* ->fault installed the pte, not return page */
+#define VM_FAULT_LOCKED        0x0200  /* ->fault locked the returned page */
 
-/*
- * Mask of VM_FAULT_ flags
- */
-#define VM_FAULT_MASK  0xff
+#define VM_FAULT_ERROR (VM_FAULT_OOM | VM_FAULT_SIGBUS)
 
 #define offset_in_page(p)      ((unsigned long)(p) & ~PAGE_MASK)
 
@@ -817,16 +793,8 @@ extern int vmtruncate(struct inode * inode, loff_t offset);
 extern int vmtruncate_range(struct inode * inode, loff_t offset, loff_t end);
 
 #ifdef CONFIG_MMU
-extern int __handle_mm_fault(struct mm_struct *mm,struct vm_area_struct *vma,
+extern int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
                        unsigned long address, int write_access);
-
-static inline int handle_mm_fault(struct mm_struct *mm,
-                       struct vm_area_struct *vma, unsigned long address,
-                       int write_access)
-{
-       return __handle_mm_fault(mm, vma, address, write_access) &
-                               (~VM_FAULT_WRITE);
-}
 #else
 static inline int handle_mm_fault(struct mm_struct *mm,
                        struct vm_area_struct *vma, unsigned long address,
index 5c3f45d..a124250 100644 (file)
@@ -346,15 +346,20 @@ static int futex_handle_fault(unsigned long address,
        vma = find_vma(mm, address);
        if (vma && address >= vma->vm_start &&
            (vma->vm_flags & VM_WRITE)) {
-               switch (handle_mm_fault(mm, vma, address, 1)) {
-               case VM_FAULT_MINOR:
-                       ret = 0;
-                       current->min_flt++;
-                       break;
-               case VM_FAULT_MAJOR:
+               int fault;
+               fault = handle_mm_fault(mm, vma, address, 1);
+               if (unlikely((fault & VM_FAULT_ERROR))) {
+#if 0
+                       /* XXX: let's do this when we verify it is OK */
+                       if (ret & VM_FAULT_OOM)
+                               ret = -ENOMEM;
+#endif
+               } else {
                        ret = 0;
-                       current->maj_flt++;
-                       break;
+                       if (fault & VM_FAULT_MAJOR)
+                               current->maj_flt++;
+                       else
+                               current->min_flt++;
                }
        }
        if (!fshared)
index 0876cc5..4fd9e3f 100644 (file)
@@ -1322,9 +1322,7 @@ int filemap_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
        struct page *page;
        unsigned long size;
        int did_readaround = 0;
-       int ret;
-
-       ret = VM_FAULT_MINOR;
+       int ret = 0;
 
        size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
        if (vmf->pgoff >= size)
@@ -1408,7 +1406,7 @@ retry_find:
         */
        mark_page_accessed(page);
        vmf->page = page;
-       return ret | FAULT_RET_LOCKED;
+       return ret | VM_FAULT_LOCKED;
 
 outside_data_content:
        /*
index 847d5d7..53ee6a2 100644 (file)
@@ -252,7 +252,7 @@ static int xip_file_fault(struct vm_area_struct *area, struct vm_fault *vmf)
 out:
        page_cache_get(page);
        vmf->page = page;
-       return VM_FAULT_MINOR;
+       return 0;
 }
 
 static struct vm_operations_struct xip_file_vm_ops = {
index aaa7c1a..c4a573b 100644 (file)
@@ -469,7 +469,7 @@ static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma,
        avoidcopy = (page_count(old_page) == 1);
        if (avoidcopy) {
                set_huge_ptep_writable(vma, address, ptep);
-               return VM_FAULT_MINOR;
+               return 0;
        }
 
        page_cache_get(old_page);
@@ -494,7 +494,7 @@ static int hugetlb_cow(struct mm_struct *mm, struct vm_area_struct *vma,
        }
        page_cache_release(new_page);
        page_cache_release(old_page);
-       return VM_FAULT_MINOR;
+       return 0;
 }
 
 static int hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma,
@@ -551,7 +551,7 @@ retry:
        if (idx >= size)
                goto backout;
 
-       ret = VM_FAULT_MINOR;
+       ret = 0;
        if (!pte_none(*ptep))
                goto backout;
 
@@ -602,7 +602,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma,
                return ret;
        }
 
-       ret = VM_FAULT_MINOR;
+       ret = 0;
 
        spin_lock(&mm->page_table_lock);
        /* Check for a racing update before calling hugetlb_cow */
@@ -641,7 +641,7 @@ int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
                        spin_unlock(&mm->page_table_lock);
                        ret = hugetlb_fault(mm, vma, vaddr, 0);
                        spin_lock(&mm->page_table_lock);
-                       if (ret == VM_FAULT_MINOR)
+                       if (!(ret & VM_FAULT_MAJOR))
                                continue;
 
                        remainder = 0;
index 23c8704..61d51da 100644 (file)
@@ -1068,31 +1068,30 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
                        cond_resched();
                        while (!(page = follow_page(vma, start, foll_flags))) {
                                int ret;
-                               ret = __handle_mm_fault(mm, vma, start,
+                               ret = handle_mm_fault(mm, vma, start,
                                                foll_flags & FOLL_WRITE);
+                               if (ret & VM_FAULT_ERROR) {
+                                       if (ret & VM_FAULT_OOM)
+                                               return i ? i : -ENOMEM;
+                                       else if (ret & VM_FAULT_SIGBUS)
+                                               return i ? i : -EFAULT;
+                                       BUG();
+                               }
+                               if (ret & VM_FAULT_MAJOR)
+                                       tsk->maj_flt++;
+                               else
+                                       tsk->min_flt++;
+
                                /*
-                                * The VM_FAULT_WRITE bit tells us that do_wp_page has
-                                * broken COW when necessary, even if maybe_mkwrite
-                                * decided not to set pte_write. We can thus safely do
-                                * subsequent page lookups as if they were reads.
+                                * The VM_FAULT_WRITE bit tells us that
+                                * do_wp_page has broken COW when necessary,
+                                * even if maybe_mkwrite decided not to set
+                                * pte_write. We can thus safely do subsequent
+                                * page lookups as if they were reads.
                                 */
                                if (ret & VM_FAULT_WRITE)
                                        foll_flags &= ~FOLL_WRITE;
-                               
-                               switch (ret & ~VM_FAULT_WRITE) {
-                               case VM_FAULT_MINOR:
-                                       tsk->min_flt++;
-                                       break;
-                               case VM_FAULT_MAJOR:
-                                       tsk->maj_flt++;
-                                       break;
-                               case VM_FAULT_SIGBUS:
-                                       return i ? i : -EFAULT;
-                               case VM_FAULT_OOM:
-                                       return i ? i : -ENOMEM;
-                               default:
-                                       BUG();
-                               }
+
                                cond_resched();
                        }
                        if (pages) {
@@ -1639,7 +1638,7 @@ static int do_wp_page(struct mm_struct *mm, struct vm_area_struct *vma,
 {
        struct page *old_page, *new_page;
        pte_t entry;
-       int reuse = 0, ret = VM_FAULT_MINOR;
+       int reuse = 0, ret = 0;
        struct page *dirty_page = NULL;
 
        old_page = vm_normal_page(vma, address, orig_pte);
@@ -1835,8 +1834,8 @@ static int unmap_mapping_range_vma(struct vm_area_struct *vma,
        /*
         * files that support invalidating or truncating portions of the
         * file from under mmaped areas must have their ->fault function
-        * return a locked page (and FAULT_RET_LOCKED code). This provides
-        * synchronisation against concurrent unmapping here.
+        * return a locked page (and set VM_FAULT_LOCKED in the return).
+        * This provides synchronisation against concurrent unmapping here.
         */
 
 again:
@@ -2140,7 +2139,7 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
        struct page *page;
        swp_entry_t entry;
        pte_t pte;
-       int ret = VM_FAULT_MINOR;
+       int ret = 0;
 
        if (!pte_unmap_same(mm, pmd, page_table, orig_pte))
                goto out;
@@ -2208,8 +2207,9 @@ static int do_swap_page(struct mm_struct *mm, struct vm_area_struct *vma,
        unlock_page(page);
 
        if (write_access) {
+               /* XXX: We could OR the do_wp_page code with this one? */
                if (do_wp_page(mm, vma, address,
-                               page_table, pmd, ptl, pte) == VM_FAULT_OOM)
+                               page_table, pmd, ptl, pte) & VM_FAULT_OOM)
                        ret = VM_FAULT_OOM;
                goto out;
        }
@@ -2280,7 +2280,7 @@ static int do_anonymous_page(struct mm_struct *mm, struct vm_area_struct *vma,
        lazy_mmu_prot_update(entry);
 unlock:
        pte_unmap_unlock(page_table, ptl);
-       return VM_FAULT_MINOR;
+       return 0;
 release:
        page_cache_release(page);
        goto unlock;
@@ -2323,11 +2323,11 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
 
        if (likely(vma->vm_ops->fault)) {
                ret = vma->vm_ops->fault(vma, &vmf);
-               if (unlikely(ret & (VM_FAULT_ERROR | FAULT_RET_NOPAGE)))
-                       return (ret & VM_FAULT_MASK);
+               if (unlikely(ret & (VM_FAULT_ERROR | VM_FAULT_NOPAGE)))
+                       return ret;
        } else {
                /* Legacy ->nopage path */
-               ret = VM_FAULT_MINOR;
+               ret = 0;
                vmf.page = vma->vm_ops->nopage(vma, address & PAGE_MASK, &ret);
                /* no page was available -- either SIGBUS or OOM */
                if (unlikely(vmf.page == NOPAGE_SIGBUS))
@@ -2340,7 +2340,7 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
         * For consistency in subsequent calls, make the faulted page always
         * locked.
         */
-       if (unlikely(!(ret & FAULT_RET_LOCKED)))
+       if (unlikely(!(ret & VM_FAULT_LOCKED)))
                lock_page(vmf.page);
        else
                VM_BUG_ON(!PageLocked(vmf.page));
@@ -2356,7 +2356,8 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
                                ret = VM_FAULT_OOM;
                                goto out;
                        }
-                       page = alloc_page_vma(GFP_HIGHUSER_MOVABLE, vma, address);
+                       page = alloc_page_vma(GFP_HIGHUSER_MOVABLE,
+                                               vma, address);
                        if (!page) {
                                ret = VM_FAULT_OOM;
                                goto out;
@@ -2384,7 +2385,7 @@ static int __do_fault(struct mm_struct *mm, struct vm_area_struct *vma,
                                 * is better done later.
                                 */
                                if (!page->mapping) {
-                                       ret = VM_FAULT_MINOR;
+                                       ret = 0;
                                        anon = 1; /* no anon but release vmf.page */
                                        goto out;
                                }
@@ -2447,7 +2448,7 @@ out_unlocked:
                put_page(dirty_page);
        }
 
-       return (ret & VM_FAULT_MASK);
+       return ret;
 }
 
 static int do_linear_fault(struct mm_struct *mm, struct vm_area_struct *vma,
@@ -2486,7 +2487,6 @@ static noinline int do_no_pfn(struct mm_struct *mm, struct vm_area_struct *vma,
        spinlock_t *ptl;
        pte_t entry;
        unsigned long pfn;
-       int ret = VM_FAULT_MINOR;
 
        pte_unmap(page_table);
        BUG_ON(!(vma->vm_flags & VM_PFNMAP));
@@ -2498,7 +2498,7 @@ static noinline int do_no_pfn(struct mm_struct *mm, struct vm_area_struct *vma,
        else if (unlikely(pfn == NOPFN_SIGBUS))
                return VM_FAULT_SIGBUS;
        else if (unlikely(pfn == NOPFN_REFAULT))
-               return VM_FAULT_MINOR;
+               return 0;
 
        page_table = pte_offset_map_lock(mm, pmd, address, &ptl);
 
@@ -2510,7 +2510,7 @@ static noinline int do_no_pfn(struct mm_struct *mm, struct vm_area_struct *vma,
                set_pte_at(mm, address, page_table, entry);
        }
        pte_unmap_unlock(page_table, ptl);
-       return ret;
+       return 0;
 }
 
 /*
@@ -2531,7 +2531,7 @@ static int do_nonlinear_fault(struct mm_struct *mm, struct vm_area_struct *vma,
        pgoff_t pgoff;
 
        if (!pte_unmap_same(mm, pmd, page_table, orig_pte))
-               return VM_FAULT_MINOR;
+               return 0;
 
        if (unlikely(!(vma->vm_flags & VM_NONLINEAR) ||
                        !(vma->vm_flags & VM_CAN_NONLINEAR))) {
@@ -2615,13 +2615,13 @@ static inline int handle_pte_fault(struct mm_struct *mm,
        }
 unlock:
        pte_unmap_unlock(pte, ptl);
-       return VM_FAULT_MINOR;
+       return 0;
 }
 
 /*
  * By the time we get here, we already hold the mm semaphore
  */
-int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
+int handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
                unsigned long address, int write_access)
 {
        pgd_t *pgd;
@@ -2650,7 +2650,7 @@ int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma,
        return handle_pte_fault(mm, vma, address, pte, pmd, write_access);
 }
 
-EXPORT_SYMBOL_GPL(__handle_mm_fault);
+EXPORT_SYMBOL_GPL(handle_mm_fault);
 
 #ifndef __PAGETABLE_PUD_FOLDED
 /*
index 0a555af..ad155c7 100644 (file)
@@ -1103,7 +1103,7 @@ static int shmem_getpage(struct inode *inode, unsigned long idx,
                return -EFBIG;
 
        if (type)
-               *type = VM_FAULT_MINOR;
+               *type = 0;
 
        /*
         * Normally, filepage is NULL on entry, and either found
@@ -1138,9 +1138,9 @@ repeat:
                if (!swappage) {
                        shmem_swp_unmap(entry);
                        /* here we actually do the io */
-                       if (type && *type == VM_FAULT_MINOR) {
+                       if (type && !(*type & VM_FAULT_MAJOR)) {
                                __count_vm_event(PGMAJFAULT);
-                               *type = VM_FAULT_MAJOR;
+                               *type |= VM_FAULT_MAJOR;
                        }
                        spin_unlock(&info->lock);
                        swappage = shmem_swapin(info, swap, idx);
@@ -1323,7 +1323,7 @@ static int shmem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
                return ((error == -ENOMEM) ? VM_FAULT_OOM : VM_FAULT_SIGBUS);
 
        mark_page_accessed(vmf->page);
-       return ret | FAULT_RET_LOCKED;
+       return ret | VM_FAULT_LOCKED;
 }
 
 #ifdef CONFIG_NUMA