linux/fs/hfsplus/bitmap.c

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/*
* linux/fs/hfsplus/bitmap.c
*
* Copyright (C) 2001
* Brad Boyer (flar@allandria.com)
* (C) 2003 Ardis Technologies <roman@ardistech.com>
*
* Handling of allocation file
*/
#include <linux/pagemap.h>
#include "hfsplus_fs.h"
#include "hfsplus_raw.h"
mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-01 14:29:47 +02:00
#define PAGE_CACHE_BITS (PAGE_SIZE * 8)
int hfsplus_block_allocate(struct super_block *sb, u32 size,
u32 offset, u32 *max)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
struct page *page;
struct address_space *mapping;
__be32 *pptr, *curr, *end;
u32 mask, start, len, n;
__be32 val;
int i;
len = *max;
if (!len)
return size;
hfs_dbg(BITMAP, "block_allocate: %u,%u,%u\n", size, offset, len);
mutex_lock(&sbi->alloc_mutex);
mapping = sbi->alloc_file->i_mapping;
page = read_mapping_page(mapping, offset / PAGE_CACHE_BITS, NULL);
hfsplus: check read_mapping_page() return value While testing more corrupted images with hfsplus, i came across one which triggered the following bug: [15840.675016] BUG: unable to handle kernel paging request at fffffffb [15840.675016] IP: [<c0116a4f>] kmap+0x15/0x56 [15840.675016] *pde = 00008067 *pte = 00000000 [15840.675016] Oops: 0000 [#1] PREEMPT DEBUG_PAGEALLOC [15840.675016] Modules linked in: [15840.675016] [15840.675016] Pid: 11575, comm: ln Not tainted (2.6.27-rc4-00123-gd3ee1b4-dirty #29) [15840.675016] EIP: 0060:[<c0116a4f>] EFLAGS: 00010202 CPU: 0 [15840.675016] EIP is at kmap+0x15/0x56 [15840.675016] EAX: 00000246 EBX: fffffffb ECX: 00000000 EDX: cab919c0 [15840.675016] ESI: 000007dd EDI: cab0bcf4 EBP: cab0bc98 ESP: cab0bc94 [15840.675016] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068 [15840.675016] Process ln (pid: 11575, ti=cab0b000 task=cab919c0 task.ti=cab0b000) [15840.675016] Stack: 00000000 cab0bcdc c0231cfb 00000000 cab0bce0 00000800 ca9290c0 fffffffb [15840.675016] cab145d0 cab919c0 cab15998 22222222 22222222 22222222 00000001 cab15960 [15840.675016] 000007dd cab0bcf4 cab0bd04 c022cb3a cab0bcf4 cab15a6c ca9290c0 00000000 [15840.675016] Call Trace: [15840.675016] [<c0231cfb>] ? hfsplus_block_allocate+0x6f/0x2d3 [15840.675016] [<c022cb3a>] ? hfsplus_file_extend+0xc4/0x1db [15840.675016] [<c022ce41>] ? hfsplus_get_block+0x8c/0x19d [15840.675016] [<c06adde4>] ? sub_preempt_count+0x9d/0xab [15840.675016] [<c019ece6>] ? __block_prepare_write+0x147/0x311 [15840.675016] [<c0161934>] ? __grab_cache_page+0x52/0x73 [15840.675016] [<c019ef4f>] ? block_write_begin+0x79/0xd5 [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c019f22a>] ? cont_write_begin+0x27f/0x2af [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c0139ebe>] ? tick_program_event+0x28/0x4c [15840.675016] [<c013bd35>] ? trace_hardirqs_off+0xb/0xd [15840.675016] [<c022b723>] ? hfsplus_write_begin+0x2d/0x32 [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c0161988>] ? pagecache_write_begin+0x33/0x107 [15840.675016] [<c01879e5>] ? __page_symlink+0x3c/0xae [15840.675016] [<c019ad34>] ? __mark_inode_dirty+0x12f/0x137 [15840.675016] [<c0187a70>] ? page_symlink+0x19/0x1e [15840.675016] [<c022e6eb>] ? hfsplus_symlink+0x41/0xa6 [15840.675016] [<c01886a9>] ? vfs_symlink+0x99/0x101 [15840.675016] [<c018a2f6>] ? sys_symlinkat+0x6b/0xad [15840.675016] [<c018a348>] ? sys_symlink+0x10/0x12 [15840.675016] [<c01038bd>] ? sysenter_do_call+0x12/0x31 [15840.675016] ======================= [15840.675016] Code: 00 00 75 10 83 3d 88 2f ec c0 02 75 07 89 d0 e8 12 56 05 00 5d c3 55 ba 06 00 00 00 89 e5 53 89 c3 b8 3d eb 7e c0 e8 16 74 00 00 <8b> 03 c1 e8 1e 69 c0 d8 02 00 00 05 b8 69 8e c0 2b 80 c4 02 00 [15840.675016] EIP: [<c0116a4f>] kmap+0x15/0x56 SS:ESP 0068:cab0bc94 [15840.675016] ---[ end trace 4fea40dad6b70e5f ]--- This happens because the return value of read_mapping_page() is passed on to kmap unchecked. The bug is triggered after the first read_mapping_page() in hfsplus_block_allocate(), this patch fixes all three usages in this functions but leaves the ones further down in the file unchanged. Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 07:04:10 +02:00
if (IS_ERR(page)) {
start = size;
goto out;
}
pptr = kmap(page);
curr = pptr + (offset & (PAGE_CACHE_BITS - 1)) / 32;
i = offset % 32;
offset &= ~(PAGE_CACHE_BITS - 1);
if ((size ^ offset) / PAGE_CACHE_BITS)
end = pptr + PAGE_CACHE_BITS / 32;
else
end = pptr + ((size + 31) & (PAGE_CACHE_BITS - 1)) / 32;
/* scan the first partial u32 for zero bits */
val = *curr;
if (~val) {
n = be32_to_cpu(val);
mask = (1U << 31) >> i;
for (; i < 32; mask >>= 1, i++) {
if (!(n & mask))
goto found;
}
}
curr++;
/* scan complete u32s for the first zero bit */
while (1) {
while (curr < end) {
val = *curr;
if (~val) {
n = be32_to_cpu(val);
mask = 1 << 31;
for (i = 0; i < 32; mask >>= 1, i++) {
if (!(n & mask))
goto found;
}
}
curr++;
}
kunmap(page);
offset += PAGE_CACHE_BITS;
if (offset >= size)
break;
page = read_mapping_page(mapping, offset / PAGE_CACHE_BITS,
NULL);
hfsplus: check read_mapping_page() return value While testing more corrupted images with hfsplus, i came across one which triggered the following bug: [15840.675016] BUG: unable to handle kernel paging request at fffffffb [15840.675016] IP: [<c0116a4f>] kmap+0x15/0x56 [15840.675016] *pde = 00008067 *pte = 00000000 [15840.675016] Oops: 0000 [#1] PREEMPT DEBUG_PAGEALLOC [15840.675016] Modules linked in: [15840.675016] [15840.675016] Pid: 11575, comm: ln Not tainted (2.6.27-rc4-00123-gd3ee1b4-dirty #29) [15840.675016] EIP: 0060:[<c0116a4f>] EFLAGS: 00010202 CPU: 0 [15840.675016] EIP is at kmap+0x15/0x56 [15840.675016] EAX: 00000246 EBX: fffffffb ECX: 00000000 EDX: cab919c0 [15840.675016] ESI: 000007dd EDI: cab0bcf4 EBP: cab0bc98 ESP: cab0bc94 [15840.675016] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068 [15840.675016] Process ln (pid: 11575, ti=cab0b000 task=cab919c0 task.ti=cab0b000) [15840.675016] Stack: 00000000 cab0bcdc c0231cfb 00000000 cab0bce0 00000800 ca9290c0 fffffffb [15840.675016] cab145d0 cab919c0 cab15998 22222222 22222222 22222222 00000001 cab15960 [15840.675016] 000007dd cab0bcf4 cab0bd04 c022cb3a cab0bcf4 cab15a6c ca9290c0 00000000 [15840.675016] Call Trace: [15840.675016] [<c0231cfb>] ? hfsplus_block_allocate+0x6f/0x2d3 [15840.675016] [<c022cb3a>] ? hfsplus_file_extend+0xc4/0x1db [15840.675016] [<c022ce41>] ? hfsplus_get_block+0x8c/0x19d [15840.675016] [<c06adde4>] ? sub_preempt_count+0x9d/0xab [15840.675016] [<c019ece6>] ? __block_prepare_write+0x147/0x311 [15840.675016] [<c0161934>] ? __grab_cache_page+0x52/0x73 [15840.675016] [<c019ef4f>] ? block_write_begin+0x79/0xd5 [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c019f22a>] ? cont_write_begin+0x27f/0x2af [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c0139ebe>] ? tick_program_event+0x28/0x4c [15840.675016] [<c013bd35>] ? trace_hardirqs_off+0xb/0xd [15840.675016] [<c022b723>] ? hfsplus_write_begin+0x2d/0x32 [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c0161988>] ? pagecache_write_begin+0x33/0x107 [15840.675016] [<c01879e5>] ? __page_symlink+0x3c/0xae [15840.675016] [<c019ad34>] ? __mark_inode_dirty+0x12f/0x137 [15840.675016] [<c0187a70>] ? page_symlink+0x19/0x1e [15840.675016] [<c022e6eb>] ? hfsplus_symlink+0x41/0xa6 [15840.675016] [<c01886a9>] ? vfs_symlink+0x99/0x101 [15840.675016] [<c018a2f6>] ? sys_symlinkat+0x6b/0xad [15840.675016] [<c018a348>] ? sys_symlink+0x10/0x12 [15840.675016] [<c01038bd>] ? sysenter_do_call+0x12/0x31 [15840.675016] ======================= [15840.675016] Code: 00 00 75 10 83 3d 88 2f ec c0 02 75 07 89 d0 e8 12 56 05 00 5d c3 55 ba 06 00 00 00 89 e5 53 89 c3 b8 3d eb 7e c0 e8 16 74 00 00 <8b> 03 c1 e8 1e 69 c0 d8 02 00 00 05 b8 69 8e c0 2b 80 c4 02 00 [15840.675016] EIP: [<c0116a4f>] kmap+0x15/0x56 SS:ESP 0068:cab0bc94 [15840.675016] ---[ end trace 4fea40dad6b70e5f ]--- This happens because the return value of read_mapping_page() is passed on to kmap unchecked. The bug is triggered after the first read_mapping_page() in hfsplus_block_allocate(), this patch fixes all three usages in this functions but leaves the ones further down in the file unchanged. Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 07:04:10 +02:00
if (IS_ERR(page)) {
start = size;
goto out;
}
curr = pptr = kmap(page);
if ((size ^ offset) / PAGE_CACHE_BITS)
end = pptr + PAGE_CACHE_BITS / 32;
else
end = pptr + ((size + 31) & (PAGE_CACHE_BITS - 1)) / 32;
}
hfs_dbg(BITMAP, "bitmap full\n");
start = size;
goto out;
found:
start = offset + (curr - pptr) * 32 + i;
if (start >= size) {
hfs_dbg(BITMAP, "bitmap full\n");
goto out;
}
/* do any partial u32 at the start */
len = min(size - start, len);
while (1) {
n |= mask;
if (++i >= 32)
break;
mask >>= 1;
if (!--len || n & mask)
goto done;
}
if (!--len)
goto done;
*curr++ = cpu_to_be32(n);
/* do full u32s */
while (1) {
while (curr < end) {
n = be32_to_cpu(*curr);
if (len < 32)
goto last;
if (n) {
len = 32;
goto last;
}
*curr++ = cpu_to_be32(0xffffffff);
len -= 32;
}
set_page_dirty(page);
kunmap(page);
offset += PAGE_CACHE_BITS;
page = read_mapping_page(mapping, offset / PAGE_CACHE_BITS,
NULL);
hfsplus: check read_mapping_page() return value While testing more corrupted images with hfsplus, i came across one which triggered the following bug: [15840.675016] BUG: unable to handle kernel paging request at fffffffb [15840.675016] IP: [<c0116a4f>] kmap+0x15/0x56 [15840.675016] *pde = 00008067 *pte = 00000000 [15840.675016] Oops: 0000 [#1] PREEMPT DEBUG_PAGEALLOC [15840.675016] Modules linked in: [15840.675016] [15840.675016] Pid: 11575, comm: ln Not tainted (2.6.27-rc4-00123-gd3ee1b4-dirty #29) [15840.675016] EIP: 0060:[<c0116a4f>] EFLAGS: 00010202 CPU: 0 [15840.675016] EIP is at kmap+0x15/0x56 [15840.675016] EAX: 00000246 EBX: fffffffb ECX: 00000000 EDX: cab919c0 [15840.675016] ESI: 000007dd EDI: cab0bcf4 EBP: cab0bc98 ESP: cab0bc94 [15840.675016] DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068 [15840.675016] Process ln (pid: 11575, ti=cab0b000 task=cab919c0 task.ti=cab0b000) [15840.675016] Stack: 00000000 cab0bcdc c0231cfb 00000000 cab0bce0 00000800 ca9290c0 fffffffb [15840.675016] cab145d0 cab919c0 cab15998 22222222 22222222 22222222 00000001 cab15960 [15840.675016] 000007dd cab0bcf4 cab0bd04 c022cb3a cab0bcf4 cab15a6c ca9290c0 00000000 [15840.675016] Call Trace: [15840.675016] [<c0231cfb>] ? hfsplus_block_allocate+0x6f/0x2d3 [15840.675016] [<c022cb3a>] ? hfsplus_file_extend+0xc4/0x1db [15840.675016] [<c022ce41>] ? hfsplus_get_block+0x8c/0x19d [15840.675016] [<c06adde4>] ? sub_preempt_count+0x9d/0xab [15840.675016] [<c019ece6>] ? __block_prepare_write+0x147/0x311 [15840.675016] [<c0161934>] ? __grab_cache_page+0x52/0x73 [15840.675016] [<c019ef4f>] ? block_write_begin+0x79/0xd5 [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c019f22a>] ? cont_write_begin+0x27f/0x2af [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c0139ebe>] ? tick_program_event+0x28/0x4c [15840.675016] [<c013bd35>] ? trace_hardirqs_off+0xb/0xd [15840.675016] [<c022b723>] ? hfsplus_write_begin+0x2d/0x32 [15840.675016] [<c022cdb5>] ? hfsplus_get_block+0x0/0x19d [15840.675016] [<c0161988>] ? pagecache_write_begin+0x33/0x107 [15840.675016] [<c01879e5>] ? __page_symlink+0x3c/0xae [15840.675016] [<c019ad34>] ? __mark_inode_dirty+0x12f/0x137 [15840.675016] [<c0187a70>] ? page_symlink+0x19/0x1e [15840.675016] [<c022e6eb>] ? hfsplus_symlink+0x41/0xa6 [15840.675016] [<c01886a9>] ? vfs_symlink+0x99/0x101 [15840.675016] [<c018a2f6>] ? sys_symlinkat+0x6b/0xad [15840.675016] [<c018a348>] ? sys_symlink+0x10/0x12 [15840.675016] [<c01038bd>] ? sysenter_do_call+0x12/0x31 [15840.675016] ======================= [15840.675016] Code: 00 00 75 10 83 3d 88 2f ec c0 02 75 07 89 d0 e8 12 56 05 00 5d c3 55 ba 06 00 00 00 89 e5 53 89 c3 b8 3d eb 7e c0 e8 16 74 00 00 <8b> 03 c1 e8 1e 69 c0 d8 02 00 00 05 b8 69 8e c0 2b 80 c4 02 00 [15840.675016] EIP: [<c0116a4f>] kmap+0x15/0x56 SS:ESP 0068:cab0bc94 [15840.675016] ---[ end trace 4fea40dad6b70e5f ]--- This happens because the return value of read_mapping_page() is passed on to kmap unchecked. The bug is triggered after the first read_mapping_page() in hfsplus_block_allocate(), this patch fixes all three usages in this functions but leaves the ones further down in the file unchanged. Signed-off-by: Eric Sesterhenn <snakebyte@gmx.de> Cc: Roman Zippel <zippel@linux-m68k.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-16 07:04:10 +02:00
if (IS_ERR(page)) {
start = size;
goto out;
}
pptr = kmap(page);
curr = pptr;
end = pptr + PAGE_CACHE_BITS / 32;
}
last:
/* do any partial u32 at end */
mask = 1U << 31;
for (i = 0; i < len; i++) {
if (n & mask)
break;
n |= mask;
mask >>= 1;
}
done:
*curr = cpu_to_be32(n);
set_page_dirty(page);
kunmap(page);
*max = offset + (curr - pptr) * 32 + i - start;
sbi->free_blocks -= *max;
hfsplus_mark_mdb_dirty(sb);
hfs_dbg(BITMAP, "-> %u,%u\n", start, *max);
out:
mutex_unlock(&sbi->alloc_mutex);
return start;
}
int hfsplus_block_free(struct super_block *sb, u32 offset, u32 count)
{
struct hfsplus_sb_info *sbi = HFSPLUS_SB(sb);
struct page *page;
struct address_space *mapping;
__be32 *pptr, *curr, *end;
u32 mask, len, pnr;
int i;
/* is there any actual work to be done? */
if (!count)
return 0;
hfs_dbg(BITMAP, "block_free: %u,%u\n", offset, count);
/* are all of the bits in range? */
if ((offset + count) > sbi->total_blocks)
return -ENOENT;
mutex_lock(&sbi->alloc_mutex);
mapping = sbi->alloc_file->i_mapping;
pnr = offset / PAGE_CACHE_BITS;
page = read_mapping_page(mapping, pnr, NULL);
if (IS_ERR(page))
goto kaboom;
pptr = kmap(page);
curr = pptr + (offset & (PAGE_CACHE_BITS - 1)) / 32;
end = pptr + PAGE_CACHE_BITS / 32;
len = count;
/* do any partial u32 at the start */
i = offset % 32;
if (i) {
int j = 32 - i;
mask = 0xffffffffU << j;
if (j > count) {
mask |= 0xffffffffU >> (i + count);
*curr++ &= cpu_to_be32(mask);
goto out;
}
*curr++ &= cpu_to_be32(mask);
count -= j;
}
/* do full u32s */
while (1) {
while (curr < end) {
if (count < 32)
goto done;
*curr++ = 0;
count -= 32;
}
if (!count)
break;
set_page_dirty(page);
kunmap(page);
page = read_mapping_page(mapping, ++pnr, NULL);
if (IS_ERR(page))
goto kaboom;
pptr = kmap(page);
curr = pptr;
end = pptr + PAGE_CACHE_BITS / 32;
}
done:
/* do any partial u32 at end */
if (count) {
mask = 0xffffffffU >> count;
*curr &= cpu_to_be32(mask);
}
out:
set_page_dirty(page);
kunmap(page);
sbi->free_blocks += len;
hfsplus_mark_mdb_dirty(sb);
mutex_unlock(&sbi->alloc_mutex);
return 0;
kaboom:
pr_crit("unable to mark blocks free: error %ld\n", PTR_ERR(page));
mutex_unlock(&sbi->alloc_mutex);
return -EIO;
}