Linux-2.6.12 memory mapping broken

From: Richard B. Johnson
Date: Mon Jun 20 2005 - 15:10:34 EST



To the memory expert that made the massive changes to mm/memory.c:

This shows debugging info from a driver that allocates and
memory-maps memory the following way:

(1) The kernel is told it has only `mem=768m` of memory.
(2) The number of kernel pages is found from variable 'num_physpages'
(3) DMA buffer allocation starts at (num_physpages * PAGE_SIZE) +
PAGE_SIZE.
(4) The remaining pages are ioremap_nocache() by the driver.
(4) The number of remaining writable pages are determined by the code
trying to write/read from the end of each new ioremap_nocache() pages.
(5) In this case, we have (0x04004000 >> PAGE_SHIFT) writable pages
or 0x04004000 bytes available.

Code up to linux-2.6.11.9 allowed me to memory-map this to user-space
so I could DMA data directly to user-space, a mandatory customer
requirement.

Memory allocation is 18656 bytes
len = 67125248 (04004000)
ACPI: PCI interrupt 0000:02:03.0[A] -> GSI 19 (level, low) -> IRQ 19
Analogic Corp DLB : Found 000012d6 (00008004) using IRQ 19
PCI: Enabling device 0000:02:03.0 (0106 -> 0107)
ACPI: PCI interrupt 0000:02:03.0[A] -> GSI 19 (level, low) -> IRQ 19
Analogic Corp DLB : Installed 12d6:8004 IRQ19 slot:0203 DMA:30001000
Analogic Corp DLB : Initialization complete
DIF = 74900 ref = 139621
Analogic Corp DLB : Start sequencer
ioctl
DATALINK_VERS
ioctl
DATALINK_FPGA
ioctl
DATALINK_GETPHYS
ioctl
DATALINK_GETMEMLEN
mmap
UNIQUE.dma.len = 04001fe0
vma->vm_end-vma->vm_start=04002000
About to execute remap_pfn_range
vma->vm_start = 20000000
base address = 30003000
length = 04001fe0 >> PAGE_SHIFT
vma->vm_page_prot = 0000003f
returned value = 0
ioctl
DATALINK_SET_ADDRESS
ioctl
DATALINK_GET_MODE

The above worked.

Code in linux-2.6.12 fails with the following (remap_pfn_range
gets the exact same values):

Memory allocation is 18656 bytes
len = 67125248 (04004000)
ACPI: PCI Interrupt 0000:02:03.0[A] -> GSI 19 (level, low) -> IRQ 19
Analogic Corp DLB : Found 000012d6 (00008004) using IRQ 19
PCI: Enabling device 0000:02:03.0 (0106 -> 0107)
ACPI: PCI Interrupt 0000:02:03.0[A] -> GSI 19 (level, low) -> IRQ 19
Analogic Corp DLB : Installed 12d6:8004 IRQ19 slot:0203 DMA:30001000
Analogic Corp DLB : Initialization complete
DIF = 60144 ref = 139622
Analogic Corp DLB : Start sequencer
ioctl
DATALINK_VERS
ioctl
DATALINK_FPGA
ioctl
DATALINK_GETPHYS
ioctl
DATALINK_GETMEMLEN
mmap
UNIQUE.dma.len = 04001fe0
vma->vm_end-vma->vm_start=04002000
About to execute remap_pfn_range
vma->vm_start = 20000000
base address = 30003000
length = 04001fe0 >> PAGE_SHIFT
vma->vm_page_prot = 0000003f
------------[ cut here ]------------
kernel BUG at mm/memory.c:1112!
invalid operand: 0000 [#1]
PREEMPT SMP Modules linked in: HeavyLink parport_pc lp parport autofs4 rfcomm l2cap bluetooth nfsd exportfs lockd sunrpc e100 mii ipt_REJECT ipt_state ip_conntrack iptable_filter ip_tables floppy sg sr_mod microcode nls_cp437 msdos fat dm_mod uhci_hcd ehci_hcd video container button battery ac rtc ipv6 ext3 jbd ata_piix libata aic7xxx scsi_transport_spi sd_mod scsi_mod
CPU: 0
EIP: 0060:[<c01577f0>] Not tainted VLI
EFLAGS: 00010206 (2.6.12) EIP is at remap_pte_range+0x70/0x80
eax: 20200a30 ebx: 00034403 ecx: 0000000c edx: e0bc3000
esi: 24400000 edi: 24001fe0 ebp: 0000003f esp: e33b5ea0
ds: 007b es: 007b ss: 0068
Process ftest (pid: 5048, threadinfo=e33b4000 task=edb31550)
Stack: 24000000 e0e4e240 24001fe0 24001fe0 c01578b4 ee0b2300 e0e4e240 24000000
24001fe0 00034003 0000003f 24001fdf fffffff4 ee0b2340 ee0b2300 00000000
30003000 ee5c938c dedc8000 f0ab662d ee5c938c 20000000 00010003 04001fe0 Call Trace:
[<c01578b4>] remap_pfn_range+0xb4/0x100
[<f0ab662d>] dma_buffer+0x35781/0x36d50 [HeavyLink]
[<c015ade6>] get_unmapped_area+0x56/0xb0
[<c015a707>] do_mmap_pgoff+0x3a7/0x7f0
[<c017bb37>] do_ioctl+0x77/0xa0
[<c010aa8e>] sys_mmap2+0x9e/0xe0
[<c01043cb>] sysenter_past_esp+0x54/0x75
Code: d8 c1 e0 05 01 c8 8b 00 f6 c4 08 74 09 89 d8 c1 e0 0c 09 e8 89 02 81 c6 00 10 00 00 43 83 c2 04 39 fe 75 c7 31 c0 5b 5e 5f 5d c3 <0f> 0b 58 04 07 37 35 c0 eb bc 8d b6 00 00 00 00 55 57 56 53 83
<3>Debug: sleeping function called from invalid context at include/linux/rwsem.h:43
in_atomic():1, irqs_disabled():0
[<c011f417>] __might_sleep+0xa7/0xb0
[<c0122b31>] profile_task_exit+0x21/0x60
[<c0124c7a>] do_exit+0x1a/0x3a0
[<c012007b>] copy_files+0xb/0x320
[<c0105728>] die+0x188/0x190
[<c0105b00>] do_invalid_op+0x0/0xd0
[<c0105bb2>] do_invalid_op+0xb2/0xd0
[<c0235084>] set_cursor+0x64/0x80
[<c01577f0>] remap_pte_range+0x70/0x80
[<c014c760>] prep_new_page+0x60/0x70
[<c014cd49>] buffered_rmqueue+0x119/0x270
[<c014d243>] __alloc_pages+0x2f3/0x4a0
[<c0104f3b>] error_code+0x4f/0x54
[<c01577f0>] remap_pte_range+0x70/0x80
[<c01578b4>] remap_pfn_range+0xb4/0x100
[<f0ab662d>] dma_buffer+0x35781/0x36d50 [HeavyLink]
[<c015ade6>] get_unmapped_area+0x56/0xb0
[<c015a707>] do_mmap_pgoff+0x3a7/0x7f0
[<c017bb37>] do_ioctl+0x77/0xa0
[<c010aa8e>] sys_mmap2+0x9e/0xe0
[<c01043cb>] sysenter_past_esp+0x54/0x75
note: ftest[5048] exited with preempt_count 1
scheduling while atomic: ftest/0x00000001/5048
[<c033af54>] schedule+0xcc4/0xcd0
[<c012259e>] release_console_sem+0x7e/0xc0
[<c01223cd>] vprintk+0x19d/0x250
[<c033bc7d>] rwsem_down_read_failed+0xad/0x1a0
[<c01043cb>] sysenter_past_esp+0x54/0x75
[<c0126060>] .text.lock.exit+0x27/0x87
[<c0124d27>] do_exit+0xc7/0x3a0
[<c0105728>] die+0x188/0x190
[<c0105b00>] do_invalid_op+0x0/0xd0
[<c0105bb2>] do_invalid_op+0xb2/0xd0
[<c0235084>] set_cursor+0x64/0x80
[<c01577f0>] remap_pte_range+0x70/0x80
[<c014c760>] prep_new_page+0x60/0x70
[<c014cd49>] buffered_rmqueue+0x119/0x270
[<c014d243>] __alloc_pages+0x2f3/0x4a0
[<c0104f3b>] error_code+0x4f/0x54
[<c01577f0>] remap_pte_range+0x70/0x80
[<c01578b4>] remap_pfn_range+0xb4/0x100
[<f0ab662d>] dma_buffer+0x35781/0x36d50 [HeavyLink]
[<c015ade6>] get_unmapped_area+0x56/0xb0
[<c015a707>] do_mmap_pgoff+0x3a7/0x7f0
[<c017bb37>] do_ioctl+0x77/0xa0
[<c010aa8e>] sys_mmap2+0x9e/0xe0
[<c01043cb>] sysenter_past_esp+0x54/0x75


There are MAJOR changes that have been made to linux-2.6.12 that
no longer allow me to memory-map this memory. Would whoever made
these changes please review them to make sure that I (and others)
can still remap memory that the kernel didn't 'own' and was
mapped using ioremap_nocache().

I can test any patches.


--- /usr/src/linux-2.6.11.9/mm/memory.c 2005-05-11 18:41:52.000000000 -0400
+++ /usr/src/linux-2.6.12/mm/memory.c 2005-06-20 11:51:45.000000000 -0400
@@ -46,7 +46,6 @@
#include <linux/highmem.h>
#include <linux/pagemap.h>
#include <linux/rmap.h>
-#include <linux/acct.h>
#include <linux/module.h>
#include <linux/init.h>

@@ -84,116 +83,205 @@
EXPORT_SYMBOL(vmalloc_earlyreserve);

/*
- * Note: this doesn't free the actual pages themselves. That
- * has been handled earlier when unmapping all the memory regions.
+ * If a p?d_bad entry is found while walking page tables, report
+ * the error, before resetting entry to p?d_none. Usually (but
+ * very seldom) called out from the p?d_none_or_clear_bad macros.
*/
-static inline void clear_pmd_range(struct mmu_gather *tlb, pmd_t *pmd, unsigned long start, unsigned long end)
+
+void pgd_clear_bad(pgd_t *pgd)
{
- struct page *page;
+ pgd_ERROR(*pgd);
+ pgd_clear(pgd);
+}

- if (pmd_none(*pmd))
- return;
- if (unlikely(pmd_bad(*pmd))) {
- pmd_ERROR(*pmd);
- pmd_clear(pmd);
- return;
- }
- if (!((start | end) & ~PMD_MASK)) {
- /* Only clear full, aligned ranges */
- page = pmd_page(*pmd);
- pmd_clear(pmd);
- dec_page_state(nr_page_table_pages);
- tlb->mm->nr_ptes--;
- pte_free_tlb(tlb, page);
- }
+void pud_clear_bad(pud_t *pud)
+{
+ pud_ERROR(*pud);
+ pud_clear(pud);
}

-static inline void clear_pud_range(struct mmu_gather *tlb, pud_t *pud, unsigned long start, unsigned long end)
+void pmd_clear_bad(pmd_t *pmd)
{
- unsigned long addr = start, next;
- pmd_t *pmd, *__pmd;
+ pmd_ERROR(*pmd);
+ pmd_clear(pmd);
+}

- if (pud_none(*pud))
- return;
- if (unlikely(pud_bad(*pud))) {
- pud_ERROR(*pud);
- pud_clear(pud);
- return;
- }
+/*
+ * Note: this doesn't free the actual pages themselves. That
+ * has been handled earlier when unmapping all the memory regions.
+ */
+static void free_pte_range(struct mmu_gather *tlb, pmd_t *pmd)
+{
+ struct page *page = pmd_page(*pmd);
+ pmd_clear(pmd);
+ pte_free_tlb(tlb, page);
+ dec_page_state(nr_page_table_pages);
+ tlb->mm->nr_ptes--;
+}
+
+static inline void free_pmd_range(struct mmu_gather *tlb, pud_t *pud,
+ unsigned long addr, unsigned long end,
+ unsigned long floor, unsigned long ceiling)
+{
+ pmd_t *pmd;
+ unsigned long next;
+ unsigned long start;

- pmd = __pmd = pmd_offset(pud, start);
+ start = addr;
+ pmd = pmd_offset(pud, addr);
do {
- next = (addr + PMD_SIZE) & PMD_MASK;
- if (next > end || next <= addr)
- next = end;
- - clear_pmd_range(tlb, pmd, addr, next);
- pmd++;
- addr = next;
- } while (addr && (addr < end));
+ next = pmd_addr_end(addr, end);
+ if (pmd_none_or_clear_bad(pmd))
+ continue;
+ free_pte_range(tlb, pmd);
+ } while (pmd++, addr = next, addr != end);

- if (!((start | end) & ~PUD_MASK)) {
- /* Only clear full, aligned ranges */
- pud_clear(pud);
- pmd_free_tlb(tlb, __pmd);
+ start &= PUD_MASK;
+ if (start < floor)
+ return;
+ if (ceiling) {
+ ceiling &= PUD_MASK;
+ if (!ceiling)
+ return;
}
-}
+ if (end - 1 > ceiling - 1)
+ return;

+ pmd = pmd_offset(pud, start);
+ pud_clear(pud);
+ pmd_free_tlb(tlb, pmd);
+}

-static inline void clear_pgd_range(struct mmu_gather *tlb, pgd_t *pgd, unsigned long start, unsigned long end)
+static inline void free_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
+ unsigned long addr, unsigned long end,
+ unsigned long floor, unsigned long ceiling)
{
- unsigned long addr = start, next;
- pud_t *pud, *__pud;
-
- if (pgd_none(*pgd))
- return;
- if (unlikely(pgd_bad(*pgd))) {
- pgd_ERROR(*pgd);
- pgd_clear(pgd);
- return;
- }
+ pud_t *pud;
+ unsigned long next;
+ unsigned long start;

- pud = __pud = pud_offset(pgd, start);
+ start = addr;
+ pud = pud_offset(pgd, addr);
do {
- next = (addr + PUD_SIZE) & PUD_MASK;
- if (next > end || next <= addr)
- next = end;
- - clear_pud_range(tlb, pud, addr, next);
- pud++;
- addr = next;
- } while (addr && (addr < end));
+ next = pud_addr_end(addr, end);
+ if (pud_none_or_clear_bad(pud))
+ continue;
+ free_pmd_range(tlb, pud, addr, next, floor, ceiling);
+ } while (pud++, addr = next, addr != end);

- if (!((start | end) & ~PGDIR_MASK)) {
- /* Only clear full, aligned ranges */
- pgd_clear(pgd);
- pud_free_tlb(tlb, __pud);
+ start &= PGDIR_MASK;
+ if (start < floor)
+ return;
+ if (ceiling) {
+ ceiling &= PGDIR_MASK;
+ if (!ceiling)
+ return;
}
+ if (end - 1 > ceiling - 1)
+ return;
+
+ pud = pud_offset(pgd, start);
+ pgd_clear(pgd);
+ pud_free_tlb(tlb, pud);
}

/*
- * This function clears user-level page tables of a process.
+ * This function frees user-level page tables of a process.
*
* Must be called with pagetable lock held.
*/
-void clear_page_range(struct mmu_gather *tlb, unsigned long start, unsigned long end)
+void free_pgd_range(struct mmu_gather **tlb,
+ unsigned long addr, unsigned long end,
+ unsigned long floor, unsigned long ceiling)
{
- unsigned long addr = start, next;
- pgd_t * pgd = pgd_offset(tlb->mm, start);
- unsigned long i;
-
- for (i = pgd_index(start); i <= pgd_index(end-1); i++) {
- next = (addr + PGDIR_SIZE) & PGDIR_MASK;
- if (next > end || next <= addr)
- next = end;
- - clear_pgd_range(tlb, pgd, addr, next);
- pgd++;
- addr = next;
+ pgd_t *pgd;
+ unsigned long next;
+ unsigned long start;
+
+ /*
+ * The next few lines have given us lots of grief...
+ *
+ * Why are we testing PMD* at this top level? Because often
+ * there will be no work to do at all, and we'd prefer not to
+ * go all the way down to the bottom just to discover that.
+ *
+ * Why all these "- 1"s? Because 0 represents both the bottom
+ * of the address space and the top of it (using -1 for the
+ * top wouldn't help much: the masks would do the wrong thing).
+ * The rule is that addr 0 and floor 0 refer to the bottom of
+ * the address space, but end 0 and ceiling 0 refer to the top
+ * Comparisons need to use "end - 1" and "ceiling - 1" (though
+ * that end 0 case should be mythical).
+ *
+ * Wherever addr is brought up or ceiling brought down, we must
+ * be careful to reject "the opposite 0" before it confuses the
+ * subsequent tests. But what about where end is brought down
+ * by PMD_SIZE below? no, end can't go down to 0 there.
+ *
+ * Whereas we round start (addr) and ceiling down, by different
+ * masks at different levels, in order to test whether a table
+ * now has no other vmas using it, so can be freed, we don't
+ * bother to round floor or end up - the tests don't need that.
+ */
+
+ addr &= PMD_MASK;
+ if (addr < floor) {
+ addr += PMD_SIZE;
+ if (!addr)
+ return;
+ }
+ if (ceiling) {
+ ceiling &= PMD_MASK;
+ if (!ceiling)
+ return;
+ }
+ if (end - 1 > ceiling - 1)
+ end -= PMD_SIZE;
+ if (addr > end - 1)
+ return;
+
+ start = addr;
+ pgd = pgd_offset((*tlb)->mm, addr);
+ do {
+ next = pgd_addr_end(addr, end);
+ if (pgd_none_or_clear_bad(pgd))
+ continue;
+ free_pud_range(*tlb, pgd, addr, next, floor, ceiling);
+ } while (pgd++, addr = next, addr != end);
+
+ if (!tlb_is_full_mm(*tlb))
+ flush_tlb_pgtables((*tlb)->mm, start, end);
+}
+
+void free_pgtables(struct mmu_gather **tlb, struct vm_area_struct *vma,
+ unsigned long floor, unsigned long ceiling)
+{
+ while (vma) {
+ struct vm_area_struct *next = vma->vm_next;
+ unsigned long addr = vma->vm_start;
+
+ if (is_hugepage_only_range(vma->vm_mm, addr, HPAGE_SIZE)) {
+ hugetlb_free_pgd_range(tlb, addr, vma->vm_end,
+ floor, next? next->vm_start: ceiling);
+ } else {
+ /*
+ * Optimization: gather nearby vmas into one call down
+ */
+ while (next && next->vm_start <= vma->vm_end + PMD_SIZE
+ && !is_hugepage_only_range(vma->vm_mm, next->vm_start,
+ HPAGE_SIZE)) {
+ vma = next;
+ next = vma->vm_next;
+ }
+ free_pgd_range(tlb, addr, vma->vm_end,
+ floor, next? next->vm_start: ceiling);
+ }
+ vma = next;
}
}

-pte_t fastcall * pte_alloc_map(struct mm_struct *mm, pmd_t *pmd, unsigned long address)
+pte_t fastcall *pte_alloc_map(struct mm_struct *mm, pmd_t *pmd,
+ unsigned long address)
{
if (!pmd_present(*pmd)) {
struct page *new;
@@ -254,20 +342,7 @@
*/

static inline void
-copy_swap_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm, pte_t pte)
-{
- if (pte_file(pte))
- return;
- swap_duplicate(pte_to_swp_entry(pte));
- if (list_empty(&dst_mm->mmlist)) {
- spin_lock(&mmlist_lock);
- list_add(&dst_mm->mmlist, &src_mm->mmlist);
- spin_unlock(&mmlist_lock);
- }
-}
-
-static inline void
-copy_one_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm,
+copy_one_pte(struct mm_struct *dst_mm, struct mm_struct *src_mm,
pte_t *dst_pte, pte_t *src_pte, unsigned long vm_flags,
unsigned long addr)
{
@@ -275,12 +350,21 @@
struct page *page;
unsigned long pfn;

- /* pte contains position in swap, so copy. */
- if (!pte_present(pte)) {
- copy_swap_pte(dst_mm, src_mm, pte);
- set_pte(dst_pte, pte);
+ /* pte contains position in swap or file, so copy. */
+ if (unlikely(!pte_present(pte))) {
+ if (!pte_file(pte)) {
+ swap_duplicate(pte_to_swp_entry(pte));
+ /* make sure dst_mm is on swapoff's mmlist. */
+ if (unlikely(list_empty(&dst_mm->mmlist))) {
+ spin_lock(&mmlist_lock);
+ list_add(&dst_mm->mmlist, &src_mm->mmlist);
+ spin_unlock(&mmlist_lock);
+ }
+ }
+ set_pte_at(dst_mm, addr, dst_pte, pte);
return;
}
+
pfn = pte_pfn(pte);
/* the pte points outside of valid memory, the
* mapping is assumed to be good, meaningful
@@ -292,7 +376,7 @@
page = pfn_to_page(pfn);

if (!page || PageReserved(page)) {
- set_pte(dst_pte, pte);
+ set_pte_at(dst_mm, addr, dst_pte, pte);
return;
}

@@ -301,7 +385,7 @@
* in the parent and the child
*/
if ((vm_flags & (VM_SHARED | VM_MAYWRITE)) == VM_MAYWRITE) {
- ptep_set_wrprotect(src_pte);
+ ptep_set_wrprotect(src_mm, addr, src_pte);
pte = *src_pte;
}

@@ -313,172 +397,137 @@
pte = pte_mkclean(pte);
pte = pte_mkold(pte);
get_page(page);
- dst_mm->rss++;
+ inc_mm_counter(dst_mm, rss);
if (PageAnon(page))
- dst_mm->anon_rss++;
- set_pte(dst_pte, pte);
+ inc_mm_counter(dst_mm, anon_rss);
+ set_pte_at(dst_mm, addr, dst_pte, pte);
page_dup_rmap(page);
}

-static int copy_pte_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
+static int copy_pte_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
pmd_t *dst_pmd, pmd_t *src_pmd, struct vm_area_struct *vma,
unsigned long addr, unsigned long end)
{
pte_t *src_pte, *dst_pte;
- pte_t *s, *d;
unsigned long vm_flags = vma->vm_flags;
+ int progress;

- d = dst_pte = pte_alloc_map(dst_mm, dst_pmd, addr);
+again:
+ dst_pte = pte_alloc_map(dst_mm, dst_pmd, addr);
if (!dst_pte)
return -ENOMEM;
+ src_pte = pte_offset_map_nested(src_pmd, addr);

+ progress = 0;
spin_lock(&src_mm->page_table_lock);
- s = src_pte = pte_offset_map_nested(src_pmd, addr);
- for (; addr < end; addr += PAGE_SIZE, s++, d++) {
- if (pte_none(*s))
+ do {
+ /*
+ * We are holding two locks at this point - either of them
+ * could generate latencies in another task on another CPU.
+ */
+ if (progress >= 32 && (need_resched() ||
+ need_lockbreak(&src_mm->page_table_lock) ||
+ need_lockbreak(&dst_mm->page_table_lock)))
+ break;
+ if (pte_none(*src_pte)) {
+ progress++;
continue;
- copy_one_pte(dst_mm, src_mm, d, s, vm_flags, addr);
- }
- pte_unmap_nested(src_pte);
- pte_unmap(dst_pte);
+ }
+ copy_one_pte(dst_mm, src_mm, dst_pte, src_pte, vm_flags, addr);
+ progress += 8;
+ } while (dst_pte++, src_pte++, addr += PAGE_SIZE, addr != end);
spin_unlock(&src_mm->page_table_lock);
+
+ pte_unmap_nested(src_pte - 1);
+ pte_unmap(dst_pte - 1);
cond_resched_lock(&dst_mm->page_table_lock);
+ if (addr != end)
+ goto again;
return 0;
}

-static int copy_pmd_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
+static inline int copy_pmd_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
pud_t *dst_pud, pud_t *src_pud, struct vm_area_struct *vma,
unsigned long addr, unsigned long end)
{
pmd_t *src_pmd, *dst_pmd;
- int err = 0;
unsigned long next;

- src_pmd = pmd_offset(src_pud, addr);
dst_pmd = pmd_alloc(dst_mm, dst_pud, addr);
if (!dst_pmd)
return -ENOMEM;
-
- for (; addr < end; addr = next, src_pmd++, dst_pmd++) {
- next = (addr + PMD_SIZE) & PMD_MASK;
- if (next > end || next <= addr)
- next = end;
- if (pmd_none(*src_pmd))
- continue;
- if (pmd_bad(*src_pmd)) {
- pmd_ERROR(*src_pmd);
- pmd_clear(src_pmd);
+ src_pmd = pmd_offset(src_pud, addr);
+ do {
+ next = pmd_addr_end(addr, end);
+ if (pmd_none_or_clear_bad(src_pmd))
continue;
- }
- err = copy_pte_range(dst_mm, src_mm, dst_pmd, src_pmd,
- vma, addr, next);
- if (err)
- break;
- }
- return err;
+ if (copy_pte_range(dst_mm, src_mm, dst_pmd, src_pmd,
+ vma, addr, next))
+ return -ENOMEM;
+ } while (dst_pmd++, src_pmd++, addr = next, addr != end);
+ return 0;
}

-static int copy_pud_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
+static inline int copy_pud_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
pgd_t *dst_pgd, pgd_t *src_pgd, struct vm_area_struct *vma,
unsigned long addr, unsigned long end)
{
pud_t *src_pud, *dst_pud;
- int err = 0;
unsigned long next;

- src_pud = pud_offset(src_pgd, addr);
dst_pud = pud_alloc(dst_mm, dst_pgd, addr);
if (!dst_pud)
return -ENOMEM;
-
- for (; addr < end; addr = next, src_pud++, dst_pud++) {
- next = (addr + PUD_SIZE) & PUD_MASK;
- if (next > end || next <= addr)
- next = end;
- if (pud_none(*src_pud))
- continue;
- if (pud_bad(*src_pud)) {
- pud_ERROR(*src_pud);
- pud_clear(src_pud);
+ src_pud = pud_offset(src_pgd, addr);
+ do {
+ next = pud_addr_end(addr, end);
+ if (pud_none_or_clear_bad(src_pud))
continue;
- }
- err = copy_pmd_range(dst_mm, src_mm, dst_pud, src_pud,
- vma, addr, next);
- if (err)
- break;
- }
- return err;
+ if (copy_pmd_range(dst_mm, src_mm, dst_pud, src_pud,
+ vma, addr, next))
+ return -ENOMEM;
+ } while (dst_pud++, src_pud++, addr = next, addr != end);
+ return 0;
}

-int copy_page_range(struct mm_struct *dst, struct mm_struct *src,
+int copy_page_range(struct mm_struct *dst_mm, struct mm_struct *src_mm,
struct vm_area_struct *vma)
{
pgd_t *src_pgd, *dst_pgd;
- unsigned long addr, start, end, next;
- int err = 0;
+ unsigned long next;
+ unsigned long addr = vma->vm_start;
+ unsigned long end = vma->vm_end;

if (is_vm_hugetlb_page(vma))
- return copy_hugetlb_page_range(dst, src, vma);
-
- start = vma->vm_start;
- src_pgd = pgd_offset(src, start);
- dst_pgd = pgd_offset(dst, start);
-
- end = vma->vm_end;
- addr = start;
- while (addr && (addr < end-1)) {
- next = (addr + PGDIR_SIZE) & PGDIR_MASK;
- if (next > end || next <= addr)
- next = end;
- if (pgd_none(*src_pgd))
- goto next_pgd;
- if (pgd_bad(*src_pgd)) {
- pgd_ERROR(*src_pgd);
- pgd_clear(src_pgd);
- goto next_pgd;
- }
- err = copy_pud_range(dst, src, dst_pgd, src_pgd,
- vma, addr, next);
- if (err)
- break;
-
-next_pgd:
- src_pgd++;
- dst_pgd++;
- addr = next;
- }
+ return copy_hugetlb_page_range(dst_mm, src_mm, vma);

- return err;
+ dst_pgd = pgd_offset(dst_mm, addr);
+ src_pgd = pgd_offset(src_mm, addr);
+ do {
+ next = pgd_addr_end(addr, end);
+ if (pgd_none_or_clear_bad(src_pgd))
+ continue;
+ if (copy_pud_range(dst_mm, src_mm, dst_pgd, src_pgd,
+ vma, addr, next))
+ return -ENOMEM;
+ } while (dst_pgd++, src_pgd++, addr = next, addr != end);
+ return 0;
}

-static void zap_pte_range(struct mmu_gather *tlb,
- pmd_t *pmd, unsigned long address,
- unsigned long size, struct zap_details *details)
+static void zap_pte_range(struct mmu_gather *tlb, pmd_t *pmd,
+ unsigned long addr, unsigned long end,
+ struct zap_details *details)
{
- unsigned long offset;
- pte_t *ptep;
+ pte_t *pte;

- if (pmd_none(*pmd))
- return;
- if (unlikely(pmd_bad(*pmd))) {
- pmd_ERROR(*pmd);
- pmd_clear(pmd);
- return;
- }
- ptep = pte_offset_map(pmd, address);
- offset = address & ~PMD_MASK;
- if (offset + size > PMD_SIZE)
- size = PMD_SIZE - offset;
- size &= PAGE_MASK;
- if (details && !details->check_mapping && !details->nonlinear_vma)
- details = NULL;
- for (offset=0; offset < size; ptep++, offset += PAGE_SIZE) {
- pte_t pte = *ptep;
- if (pte_none(pte))
+ pte = pte_offset_map(pmd, addr);
+ do {
+ pte_t ptent = *pte;
+ if (pte_none(ptent))
continue;
- if (pte_present(pte)) {
+ if (pte_present(ptent)) {
struct page *page = NULL;
- unsigned long pfn = pte_pfn(pte);
+ unsigned long pfn = pte_pfn(ptent);
if (pfn_valid(pfn)) {
page = pfn_to_page(pfn);
if (PageReserved(page))
@@ -502,19 +551,20 @@
page->index > details->last_index))
continue;
}
- pte = ptep_get_and_clear(ptep);
- tlb_remove_tlb_entry(tlb, ptep, address+offset);
+ ptent = ptep_get_and_clear(tlb->mm, addr, pte);
+ tlb_remove_tlb_entry(tlb, pte, addr);
if (unlikely(!page))
continue;
if (unlikely(details) && details->nonlinear_vma
&& linear_page_index(details->nonlinear_vma,
- address+offset) != page->index)
- set_pte(ptep, pgoff_to_pte(page->index));
- if (pte_dirty(pte))
+ addr) != page->index)
+ set_pte_at(tlb->mm, addr, pte,
+ pgoff_to_pte(page->index));
+ if (pte_dirty(ptent))
set_page_dirty(page);
if (PageAnon(page))
- tlb->mm->anon_rss--;
- else if (pte_young(pte))
+ dec_mm_counter(tlb->mm, anon_rss);
+ else if (pte_young(ptent))
mark_page_accessed(page);
tlb->freed++;
page_remove_rmap(page);
@@ -527,78 +577,64 @@
*/
if (unlikely(details))
continue;
- if (!pte_file(pte))
- free_swap_and_cache(pte_to_swp_entry(pte));
- pte_clear(ptep);
- }
- pte_unmap(ptep-1);
+ if (!pte_file(ptent))
+ free_swap_and_cache(pte_to_swp_entry(ptent));
+ pte_clear(tlb->mm, addr, pte);
+ } while (pte++, addr += PAGE_SIZE, addr != end);
+ pte_unmap(pte - 1);
}

-static void zap_pmd_range(struct mmu_gather *tlb,
- pud_t *pud, unsigned long address,
- unsigned long size, struct zap_details *details)
+static inline void zap_pmd_range(struct mmu_gather *tlb, pud_t *pud,
+ unsigned long addr, unsigned long end,
+ struct zap_details *details)
{
- pmd_t * pmd;
- unsigned long end;
+ pmd_t *pmd;
+ unsigned long next;

- if (pud_none(*pud))
- return;
- if (unlikely(pud_bad(*pud))) {
- pud_ERROR(*pud);
- pud_clear(pud);
- return;
- }
- pmd = pmd_offset(pud, address);
- end = address + size;
- if (end > ((address + PUD_SIZE) & PUD_MASK))
- end = ((address + PUD_SIZE) & PUD_MASK);
+ pmd = pmd_offset(pud, addr);
do {
- zap_pte_range(tlb, pmd, address, end - address, details);
- address = (address + PMD_SIZE) & PMD_MASK; - pmd++;
- } while (address && (address < end));
+ next = pmd_addr_end(addr, end);
+ if (pmd_none_or_clear_bad(pmd))
+ continue;
+ zap_pte_range(tlb, pmd, addr, next, details);
+ } while (pmd++, addr = next, addr != end);
}

-static void zap_pud_range(struct mmu_gather *tlb,
- pgd_t * pgd, unsigned long address,
- unsigned long end, struct zap_details *details)
+static inline void zap_pud_range(struct mmu_gather *tlb, pgd_t *pgd,
+ unsigned long addr, unsigned long end,
+ struct zap_details *details)
{
- pud_t * pud;
+ pud_t *pud;
+ unsigned long next;

- if (pgd_none(*pgd))
- return;
- if (unlikely(pgd_bad(*pgd))) {
- pgd_ERROR(*pgd);
- pgd_clear(pgd);
- return;
- }
- pud = pud_offset(pgd, address);
+ pud = pud_offset(pgd, addr);
do {
- zap_pmd_range(tlb, pud, address, end - address, details);
- address = (address + PUD_SIZE) & PUD_MASK; - pud++;
- } while (address && (address < end));
+ next = pud_addr_end(addr, end);
+ if (pud_none_or_clear_bad(pud))
+ continue;
+ zap_pmd_range(tlb, pud, addr, next, details);
+ } while (pud++, addr = next, addr != end);
}

-static void unmap_page_range(struct mmu_gather *tlb,
- struct vm_area_struct *vma, unsigned long address,
- unsigned long end, struct zap_details *details)
+static void unmap_page_range(struct mmu_gather *tlb, struct vm_area_struct *vma,
+ unsigned long addr, unsigned long end,
+ struct zap_details *details)
{
- unsigned long next;
pgd_t *pgd;
- int i;
+ unsigned long next;

- BUG_ON(address >= end);
- pgd = pgd_offset(vma->vm_mm, address);
+ if (details && !details->check_mapping && !details->nonlinear_vma)
+ details = NULL;
+
+ BUG_ON(addr >= end);
tlb_start_vma(tlb, vma);
- for (i = pgd_index(address); i <= pgd_index(end-1); i++) {
- next = (address + PGDIR_SIZE) & PGDIR_MASK;
- if (next <= address || next > end)
- next = end;
- zap_pud_range(tlb, pgd, address, next, details);
- address = next;
- pgd++;
- }
+ pgd = pgd_offset(vma->vm_mm, addr);
+ do {
+ next = pgd_addr_end(addr, end);
+ if (pgd_none_or_clear_bad(pgd))
+ continue;
+ zap_pud_range(tlb, pgd, addr, next, details);
+ } while (pgd++, addr = next, addr != end);
tlb_end_vma(tlb, vma);
}

@@ -619,7 +655,7 @@
* @nr_accounted: Place number of unmapped pages in vm-accountable vma's here
* @details: details of nonlinear truncation or shared cache invalidation
*
- * Returns the number of vma's which were covered by the unmapping.
+ * Returns the end address of the unmapping (restart addr if interrupted).
*
* Unmap all pages in the vma list. Called under page_table_lock.
*
@@ -636,7 +672,7 @@
* ensure that any thus-far unmapped pages are flushed before unmap_vmas()
* drops the lock and schedules.
*/
-int unmap_vmas(struct mmu_gather **tlbp, struct mm_struct *mm,
+unsigned long unmap_vmas(struct mmu_gather **tlbp, struct mm_struct *mm,
struct vm_area_struct *vma, unsigned long start_addr,
unsigned long end_addr, unsigned long *nr_accounted,
struct zap_details *details)
@@ -644,12 +680,11 @@
unsigned long zap_bytes = ZAP_BLOCK_SIZE;
unsigned long tlb_start = 0; /* For tlb_finish_mmu */
int tlb_start_valid = 0;
- int ret = 0;
+ unsigned long start = start_addr;
spinlock_t *i_mmap_lock = details? details->i_mmap_lock: NULL;
int fullmm = tlb_is_full_mm(*tlbp);

for ( ; vma && vma->vm_start < end_addr; vma = vma->vm_next) {
- unsigned long start;
unsigned long end;

start = max(vma->vm_start, start_addr);
@@ -662,7 +697,6 @@
if (vma->vm_flags & VM_ACCOUNT)
*nr_accounted += (end - start) >> PAGE_SHIFT;

- ret++;
while (start != end) {
unsigned long block;

@@ -693,7 +727,6 @@
if (i_mmap_lock) {
/* must reset count of rss freed */
*tlbp = tlb_gather_mmu(mm, fullmm);
- details->break_addr = start;
goto out;
}
spin_unlock(&mm->page_table_lock);
@@ -707,7 +740,7 @@
}
}
out:
- return ret;
+ return start; /* which is now the end (or restart) address */
}

/**
@@ -717,7 +750,7 @@
* @size: number of bytes to zap
* @details: details of nonlinear truncation or shared cache invalidation
*/
-void zap_page_range(struct vm_area_struct *vma, unsigned long address,
+unsigned long zap_page_range(struct vm_area_struct *vma, unsigned long address,
unsigned long size, struct zap_details *details)
{
struct mm_struct *mm = vma->vm_mm;
@@ -727,16 +760,16 @@

if (is_vm_hugetlb_page(vma)) {
zap_hugepage_range(vma, address, size);
- return;
+ return end;
}

lru_add_drain();
spin_lock(&mm->page_table_lock);
tlb = tlb_gather_mmu(mm, 0);
- unmap_vmas(&tlb, mm, vma, address, end, &nr_accounted, details);
+ end = unmap_vmas(&tlb, mm, vma, address, end, &nr_accounted, details);
tlb_finish_mmu(tlb, address, end);
- acct_update_integrals();
spin_unlock(&mm->page_table_lock);
+ return end;
}

/*
@@ -987,111 +1020,78 @@

EXPORT_SYMBOL(get_user_pages);

-static void zeromap_pte_range(pte_t * pte, unsigned long address,
- unsigned long size, pgprot_t prot)
+static int zeromap_pte_range(struct mm_struct *mm, pmd_t *pmd,
+ unsigned long addr, unsigned long end, pgprot_t prot)
{
- unsigned long end;
+ pte_t *pte;

- address &= ~PMD_MASK;
- end = address + size;
- if (end > PMD_SIZE)
- end = PMD_SIZE;
+ pte = pte_alloc_map(mm, pmd, addr);
+ if (!pte)
+ return -ENOMEM;
do {
- pte_t zero_pte = pte_wrprotect(mk_pte(ZERO_PAGE(address), prot));
+ pte_t zero_pte = pte_wrprotect(mk_pte(ZERO_PAGE(addr), prot));
BUG_ON(!pte_none(*pte));
- set_pte(pte, zero_pte);
- address += PAGE_SIZE;
- pte++;
- } while (address && (address < end));
-}
-
-static inline int zeromap_pmd_range(struct mm_struct *mm, pmd_t * pmd,
- unsigned long address, unsigned long size, pgprot_t prot)
-{
- unsigned long base, end;
-
- base = address & PUD_MASK;
- address &= ~PUD_MASK;
- end = address + size;
- if (end > PUD_SIZE)
- end = PUD_SIZE;
+ set_pte_at(mm, addr, pte, zero_pte);
+ } while (pte++, addr += PAGE_SIZE, addr != end);
+ pte_unmap(pte - 1);
+ return 0;
+}
+
+static inline int zeromap_pmd_range(struct mm_struct *mm, pud_t *pud,
+ unsigned long addr, unsigned long end, pgprot_t prot)
+{
+ pmd_t *pmd;
+ unsigned long next;
+
+ pmd = pmd_alloc(mm, pud, addr);
+ if (!pmd)
+ return -ENOMEM;
do {
- pte_t * pte = pte_alloc_map(mm, pmd, base + address);
- if (!pte)
+ next = pmd_addr_end(addr, end);
+ if (zeromap_pte_range(mm, pmd, addr, next, prot))
return -ENOMEM;
- zeromap_pte_range(pte, base + address, end - address, prot);
- pte_unmap(pte);
- address = (address + PMD_SIZE) & PMD_MASK;
- pmd++;
- } while (address && (address < end));
+ } while (pmd++, addr = next, addr != end);
return 0;
}

-static inline int zeromap_pud_range(struct mm_struct *mm, pud_t * pud,
- unsigned long address,
- unsigned long size, pgprot_t prot)
-{
- unsigned long base, end;
- int error = 0;
-
- base = address & PGDIR_MASK;
- address &= ~PGDIR_MASK;
- end = address + size;
- if (end > PGDIR_SIZE)
- end = PGDIR_SIZE;
+static inline int zeromap_pud_range(struct mm_struct *mm, pgd_t *pgd,
+ unsigned long addr, unsigned long end, pgprot_t prot)
+{
+ pud_t *pud;
+ unsigned long next;
+
+ pud = pud_alloc(mm, pgd, addr);
+ if (!pud)
+ return -ENOMEM;
do {
- pmd_t * pmd = pmd_alloc(mm, pud, base + address);
- error = -ENOMEM;
- if (!pmd)
- break;
- error = zeromap_pmd_range(mm, pmd, base + address,
- end - address, prot);
- if (error)
- break;
- address = (address + PUD_SIZE) & PUD_MASK;
- pud++;
- } while (address && (address < end));
+ next = pud_addr_end(addr, end);
+ if (zeromap_pmd_range(mm, pud, addr, next, prot))
+ return -ENOMEM;
+ } while (pud++, addr = next, addr != end);
return 0;
}

-int zeromap_page_range(struct vm_area_struct *vma, unsigned long address,
- unsigned long size, pgprot_t prot)
+int zeromap_page_range(struct vm_area_struct *vma,
+ unsigned long addr, unsigned long size, pgprot_t prot)
{
- int i;
- int error = 0;
- pgd_t * pgd;
- unsigned long beg = address;
- unsigned long end = address + size;
+ pgd_t *pgd;
unsigned long next;
+ unsigned long end = addr + size;
struct mm_struct *mm = vma->vm_mm;
+ int err;

- pgd = pgd_offset(mm, address);
- flush_cache_range(vma, beg, end);
- BUG_ON(address >= end);
- BUG_ON(end > vma->vm_end);
-
+ BUG_ON(addr >= end);
+ pgd = pgd_offset(mm, addr);
+ flush_cache_range(vma, addr, end);
spin_lock(&mm->page_table_lock);
- for (i = pgd_index(address); i <= pgd_index(end-1); i++) {
- pud_t *pud = pud_alloc(mm, pgd, address);
- error = -ENOMEM;
- if (!pud)
- break;
- next = (address + PGDIR_SIZE) & PGDIR_MASK;
- if (next <= beg || next > end)
- next = end;
- error = zeromap_pud_range(mm, pud, address,
- next - address, prot);
- if (error)
+ do {
+ next = pgd_addr_end(addr, end);
+ err = zeromap_pud_range(mm, pgd, addr, next, prot);
+ if (err)
break;
- address = next;
- pgd++;
- }
- /*
- * Why flush? zeromap_pte_range has a BUG_ON for !pte_none()
- */
- flush_tlb_range(vma, beg, end);
+ } while (pgd++, addr = next, addr != end);
spin_unlock(&mm->page_table_lock);
- return error;
+ return err;
}

/*
@@ -1099,95 +1099,74 @@
* mappings are removed. any references to nonexistent pages results
* in null mappings (currently treated as "copy-on-access")
*/
-static inline void
-remap_pte_range(pte_t * pte, unsigned long address, unsigned long size,
- unsigned long pfn, pgprot_t prot)
+static int remap_pte_range(struct mm_struct *mm, pmd_t *pmd,
+ unsigned long addr, unsigned long end,
+ unsigned long pfn, pgprot_t prot)
{
- unsigned long end;
+ pte_t *pte;

- address &= ~PMD_MASK;
- end = address + size;
- if (end > PMD_SIZE)
- end = PMD_SIZE;
+ pte = pte_alloc_map(mm, pmd, addr);
+ if (!pte)
+ return -ENOMEM;
do {
BUG_ON(!pte_none(*pte));
if (!pfn_valid(pfn) || PageReserved(pfn_to_page(pfn)))
- set_pte(pte, pfn_pte(pfn, prot));
- address += PAGE_SIZE;
+ set_pte_at(mm, addr, pte, pfn_pte(pfn, prot));
pfn++;
- pte++;
- } while (address && (address < end));
+ } while (pte++, addr += PAGE_SIZE, addr != end);
+ pte_unmap(pte - 1);
+ return 0;
}

-static inline int
-remap_pmd_range(struct mm_struct *mm, pmd_t * pmd, unsigned long address,
- unsigned long size, unsigned long pfn, pgprot_t prot)
+static inline int remap_pmd_range(struct mm_struct *mm, pud_t *pud,
+ unsigned long addr, unsigned long end,
+ unsigned long pfn, pgprot_t prot)
{
- unsigned long base, end;
+ pmd_t *pmd;
+ unsigned long next;

- base = address & PUD_MASK;
- address &= ~PUD_MASK;
- end = address + size;
- if (end > PUD_SIZE)
- end = PUD_SIZE;
- pfn -= (address >> PAGE_SHIFT);
+ pfn -= addr >> PAGE_SHIFT;
+ pmd = pmd_alloc(mm, pud, addr);
+ if (!pmd)
+ return -ENOMEM;
do {
- pte_t * pte = pte_alloc_map(mm, pmd, base + address);
- if (!pte)
+ next = pmd_addr_end(addr, end);
+ if (remap_pte_range(mm, pmd, addr, next,
+ pfn + (addr >> PAGE_SHIFT), prot))
return -ENOMEM;
- remap_pte_range(pte, base + address, end - address,
- (address >> PAGE_SHIFT) + pfn, prot);
- pte_unmap(pte);
- address = (address + PMD_SIZE) & PMD_MASK;
- pmd++;
- } while (address && (address < end));
+ } while (pmd++, addr = next, addr != end);
return 0;
}

-static inline int remap_pud_range(struct mm_struct *mm, pud_t * pud,
- unsigned long address, unsigned long size,
- unsigned long pfn, pgprot_t prot)
-{
- unsigned long base, end;
- int error;
-
- base = address & PGDIR_MASK;
- address &= ~PGDIR_MASK;
- end = address + size;
- if (end > PGDIR_SIZE)
- end = PGDIR_SIZE;
- pfn -= address >> PAGE_SHIFT;
+static inline int remap_pud_range(struct mm_struct *mm, pgd_t *pgd,
+ unsigned long addr, unsigned long end,
+ unsigned long pfn, pgprot_t prot)
+{
+ pud_t *pud;
+ unsigned long next;
+
+ pfn -= addr >> PAGE_SHIFT;
+ pud = pud_alloc(mm, pgd, addr);
+ if (!pud)
+ return -ENOMEM;
do {
- pmd_t *pmd = pmd_alloc(mm, pud, base+address);
- error = -ENOMEM;
- if (!pmd)
- break;
- error = remap_pmd_range(mm, pmd, base + address, end - address,
- (address >> PAGE_SHIFT) + pfn, prot);
- if (error)
- break;
- address = (address + PUD_SIZE) & PUD_MASK;
- pud++;
- } while (address && (address < end));
- return error;
+ next = pud_addr_end(addr, end);
+ if (remap_pmd_range(mm, pud, addr, next,
+ pfn + (addr >> PAGE_SHIFT), prot))
+ return -ENOMEM;
+ } while (pud++, addr = next, addr != end);
+ return 0;
}

/* Note: this is only safe if the mm semaphore is held when called. */
-int remap_pfn_range(struct vm_area_struct *vma, unsigned long from,
+int remap_pfn_range(struct vm_area_struct *vma, unsigned long addr,
unsigned long pfn, unsigned long size, pgprot_t prot)
{
- int error = 0;
pgd_t *pgd;
- unsigned long beg = from;
- unsigned long end = from + size;
unsigned long next;
+ unsigned long end = addr + size;
struct mm_struct *mm = vma->vm_mm;
- int i;
-
- pfn -= from >> PAGE_SHIFT;
- pgd = pgd_offset(mm, from);
- flush_cache_range(vma, beg, end);
- BUG_ON(from >= end);
+ int err;

/*
* Physically remapped pages are special. Tell the
@@ -1199,31 +1178,21 @@
*/
vma->vm_flags |= VM_IO | VM_RESERVED;

+ BUG_ON(addr >= end);
+ pfn -= addr >> PAGE_SHIFT;
+ pgd = pgd_offset(mm, addr);
+ flush_cache_range(vma, addr, end);
spin_lock(&mm->page_table_lock);
- for (i = pgd_index(beg); i <= pgd_index(end-1); i++) {
- pud_t *pud = pud_alloc(mm, pgd, from);
- error = -ENOMEM;
- if (!pud)
- break;
- next = (from + PGDIR_SIZE) & PGDIR_MASK;
- if (next > end || next <= from)
- next = end;
- error = remap_pud_range(mm, pud, from, end - from,
- pfn + (from >> PAGE_SHIFT), prot);
- if (error)
+ do {
+ next = pgd_addr_end(addr, end);
+ err = remap_pud_range(mm, pgd, addr, next,
+ pfn + (addr >> PAGE_SHIFT), prot);
+ if (err)
break;
- from = next;
- pgd++;
- }
- /*
- * Why flush? remap_pte_range has a BUG_ON for !pte_none()
- */
- flush_tlb_range(vma, beg, end);
+ } while (pgd++, addr = next, addr != end);
spin_unlock(&mm->page_table_lock);
-
- return error;
+ return err;
}
-
EXPORT_SYMBOL(remap_pfn_range);

/*
@@ -1247,11 +1216,11 @@
{
pte_t entry;

- flush_cache_page(vma, address);
entry = maybe_mkwrite(pte_mkdirty(mk_pte(new_page, vma->vm_page_prot)),
vma);
ptep_establish(vma, address, page_table, entry);
update_mmu_cache(vma, address, entry);
+ lazy_mmu_prot_update(entry);
}

/*
@@ -1299,11 +1268,12 @@
int reuse = can_share_swap_page(old_page);
unlock_page(old_page);
if (reuse) {
- flush_cache_page(vma, address);
+ flush_cache_page(vma, address, pfn);
entry = maybe_mkwrite(pte_mkyoung(pte_mkdirty(pte)),
vma);
ptep_set_access_flags(vma, address, page_table, entry, 1);
update_mmu_cache(vma, address, entry);
+ lazy_mmu_prot_update(entry);
pte_unmap(page_table);
spin_unlock(&mm->page_table_lock);
return VM_FAULT_MINOR;
@@ -1337,13 +1307,12 @@
page_table = pte_offset_map(pmd, address);
if (likely(pte_same(*page_table, pte))) {
if (PageAnon(old_page))
- mm->anon_rss--;
- if (PageReserved(old_page)) {
- ++mm->rss;
- acct_update_integrals();
- update_mem_hiwater();
- } else
+ dec_mm_counter(mm, anon_rss);
+ if (PageReserved(old_page))
+ inc_mm_counter(mm, rss);
+ else
page_remove_rmap(old_page);
+ flush_cache_page(vma, address, pfn);
break_cow(vma, new_page, address, page_table);
lru_cache_add_active(new_page);
page_add_anon_rmap(new_page, vma, address);
@@ -1387,7 +1356,7 @@
* i_mmap_lock.
*
* In order to make forward progress despite repeatedly restarting some
- * large vma, note the break_addr set by unmap_vmas when it breaks out:
+ * large vma, note the restart_addr from unmap_vmas when it breaks out:
* and restart from that address when we reach that vma again. It might
* have been split or merged, shrunk or extended, but never shifted: so
* restart_addr remains valid so long as it remains in the vma's range.
@@ -1425,8 +1394,8 @@
}
}

- details->break_addr = end_addr;
- zap_page_range(vma, start_addr, end_addr - start_addr, details);
+ restart_addr = zap_page_range(vma, start_addr,
+ end_addr - start_addr, details);

/*
* We cannot rely on the break test in unmap_vmas:
@@ -1437,14 +1406,14 @@
need_break = need_resched() ||
need_lockbreak(details->i_mmap_lock);

- if (details->break_addr >= end_addr) {
+ if (restart_addr >= end_addr) {
/* We have now completed this vma: mark it so */
vma->vm_truncate_count = details->truncate_count;
if (!need_break)
return 0;
} else {
/* Note restart_addr in vma's truncate_count field */
- vma->vm_truncate_count = details->break_addr;
+ vma->vm_truncate_count = restart_addr;
if (!need_break)
goto again;
}
@@ -1732,12 +1701,13 @@
spin_lock(&mm->page_table_lock);
page_table = pte_offset_map(pmd, address);
if (unlikely(!pte_same(*page_table, orig_pte))) {
- pte_unmap(page_table);
- spin_unlock(&mm->page_table_lock);
- unlock_page(page);
- page_cache_release(page);
ret = VM_FAULT_MINOR;
- goto out;
+ goto out_nomap;
+ }
+
+ if (unlikely(!PageUptodate(page))) {
+ ret = VM_FAULT_SIGBUS;
+ goto out_nomap;
}

/* The page isn't present yet, go ahead with the fault. */
@@ -1746,10 +1716,7 @@
if (vm_swap_full())
remove_exclusive_swap_page(page);

- mm->rss++;
- acct_update_integrals();
- update_mem_hiwater();
-
+ inc_mm_counter(mm, rss);
pte = mk_pte(page, vma->vm_page_prot);
if (write_access && can_share_swap_page(page)) {
pte = maybe_mkwrite(pte_mkdirty(pte), vma);
@@ -1758,7 +1725,7 @@
unlock_page(page);

flush_icache_page(vma, page);
- set_pte(page_table, pte);
+ set_pte_at(mm, address, page_table, pte);
page_add_anon_rmap(page, vma, address);

if (write_access) {
@@ -1770,10 +1737,17 @@

/* No need to invalidate - it was non-present before */
update_mmu_cache(vma, address, pte);
+ lazy_mmu_prot_update(pte);
pte_unmap(page_table);
spin_unlock(&mm->page_table_lock);
out:
return ret;
+out_nomap:
+ pte_unmap(page_table);
+ spin_unlock(&mm->page_table_lock);
+ unlock_page(page);
+ page_cache_release(page);
+ goto out;
}

/*
@@ -1813,9 +1787,7 @@
spin_unlock(&mm->page_table_lock);
goto out;
}
- mm->rss++;
- acct_update_integrals();
- update_mem_hiwater();
+ inc_mm_counter(mm, rss);
entry = maybe_mkwrite(pte_mkdirty(mk_pte(page,
vma->vm_page_prot)),
vma);
@@ -1824,11 +1796,12 @@
page_add_anon_rmap(page, vma, addr);
}

- set_pte(page_table, entry);
+ set_pte_at(mm, addr, page_table, entry);
pte_unmap(page_table);

/* No need to invalidate - it was non-present before */
update_mmu_cache(vma, addr, entry);
+ lazy_mmu_prot_update(entry);
spin_unlock(&mm->page_table_lock);
out:
return VM_FAULT_MINOR;
@@ -1931,15 +1904,13 @@
/* Only go through if we didn't race with anybody else... */
if (pte_none(*page_table)) {
if (!PageReserved(new_page))
- ++mm->rss;
- acct_update_integrals();
- update_mem_hiwater();
+ inc_mm_counter(mm, rss);

flush_icache_page(vma, new_page);
entry = mk_pte(new_page, vma->vm_page_prot);
if (write_access)
entry = maybe_mkwrite(pte_mkdirty(entry), vma);
- set_pte(page_table, entry);
+ set_pte_at(mm, address, page_table, entry);
if (anon) {
lru_cache_add_active(new_page);
page_add_anon_rmap(new_page, vma, address);
@@ -1956,6 +1927,7 @@

/* no need to invalidate: a not-present page shouldn't be cached */
update_mmu_cache(vma, address, entry);
+ lazy_mmu_prot_update(entry);
spin_unlock(&mm->page_table_lock);
out:
return ret;
@@ -1983,7 +1955,7 @@
*/
if (!vma->vm_ops || !vma->vm_ops->populate ||
(write_access && !(vma->vm_flags & VM_SHARED))) {
- pte_clear(pte);
+ pte_clear(mm, address, pte);
return do_no_page(mm, vma, address, write_access, pte, pmd);
}

@@ -2050,6 +2022,7 @@
entry = pte_mkyoung(entry);
ptep_set_access_flags(vma, address, pte, entry, write_access);
update_mmu_cache(vma, address, entry);
+ lazy_mmu_prot_update(entry);
pte_unmap(pte);
spin_unlock(&mm->page_table_lock);
return VM_FAULT_MINOR;
@@ -2099,15 +2072,12 @@
return VM_FAULT_OOM;
}

-#ifndef __ARCH_HAS_4LEVEL_HACK
+#ifndef __PAGETABLE_PUD_FOLDED
/*
* Allocate page upper directory.
*
* We've already handled the fast-path in-line, and we own the
* page table lock.
- *
- * On a two-level or three-level page table, this ends up actually being
- * entirely optimized away.
*/
pud_t fastcall *__pud_alloc(struct mm_struct *mm, pgd_t *pgd, unsigned long address)
{
@@ -2131,15 +2101,14 @@
out:
return pud_offset(pgd, address);
}
+#endif /* __PAGETABLE_PUD_FOLDED */

+#ifndef __PAGETABLE_PMD_FOLDED
/*
* Allocate page middle directory.
*
* We've already handled the fast-path in-line, and we own the
* page table lock.
- *
- * On a two-level page table, this ends up actually being entirely
- * optimized away.
*/
pmd_t fastcall *__pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
{
@@ -2155,38 +2124,24 @@
* Because we dropped the lock, we should re-check the
* entry, as somebody else could have populated it..
*/
+#ifndef __ARCH_HAS_4LEVEL_HACK
if (pud_present(*pud)) {
pmd_free(new);
goto out;
}
pud_populate(mm, pud, new);
- out:
- return pmd_offset(pud, address);
-}
#else
-pmd_t fastcall *__pmd_alloc(struct mm_struct *mm, pud_t *pud, unsigned long address)
-{
- pmd_t *new;
-
- spin_unlock(&mm->page_table_lock);
- new = pmd_alloc_one(mm, address);
- spin_lock(&mm->page_table_lock);
- if (!new)
- return NULL;
-
- /*
- * Because we dropped the lock, we should re-check the
- * entry, as somebody else could have populated it..
- */
if (pgd_present(*pud)) {
pmd_free(new);
goto out;
}
pgd_populate(mm, pud, new);
-out:
+#endif /* __ARCH_HAS_4LEVEL_HACK */
+
+ out:
return pmd_offset(pud, address);
}
-#endif
+#endif /* __PAGETABLE_PMD_FOLDED */

int make_pages_present(unsigned long addr, unsigned long end)
{
@@ -2253,13 +2208,13 @@
* update_mem_hiwater
* - update per process rss and vm high water data
*/
-void update_mem_hiwater(void)
+void update_mem_hiwater(struct task_struct *tsk)
{
- struct task_struct *tsk = current;
-
if (tsk->mm) {
- if (tsk->mm->hiwater_rss < tsk->mm->rss)
- tsk->mm->hiwater_rss = tsk->mm->rss;
+ unsigned long rss = get_mm_counter(tsk->mm, rss);
+
+ if (tsk->mm->hiwater_rss < rss)
+ tsk->mm->hiwater_rss = rss;
if (tsk->mm->hiwater_vm < tsk->mm->total_vm)
tsk->mm->hiwater_vm = tsk->mm->total_vm;
}

Cheers,
Dick Johnson
Penguin : Linux version 2.6.12 on an i686 machine (5537.79 BogoMips).
Notice : All mail here is now cached for review by Dictator Bush.
98.36% of all statistics are fiction.
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