Commit 9426ce75 authored by Omar Sandoval's avatar Omar Sandoval Committed by David Sterba

Btrfs: fix extent buffer bitmap tests on big-endian systems

The in-memory bitmap code manipulates words and is therefore sensitive
to endianness, while the extent buffer bitmap code addresses bytes and
is byte-order agnostic. Because the byte addressing of the extent buffer
bitmaps is equivalent to a little-endian in-memory bitmap, the extent
buffer bitmap tests fail on big-endian systems.

34b3e6c9 ("Btrfs: self-tests: Fix extent buffer bitmap test fail on
BE system") worked around another endianness bug in the tests but missed
this one because ed9e4afd ("Btrfs: self-tests: Execute page
straddling test only when nodesize < PAGE_SIZE") disables this part of
the test on ppc64. That change lost the original meaning of the test,
however. We really want to test that an equivalent series of operations
using the in-memory bitmap API and the extent buffer bitmap API produces
equivalent results.

To fix this, don't use memcmp_extent_buffer() or write_extent_buffer();
do everything bit-by-bit.
Reported-by: default avatarAnatoly Pugachev <matorola@gmail.com>
Tested-by: default avatarAnatoly Pugachev <matorola@gmail.com>
Tested-by: default avatarFeifei Xu <xufeifei@linux.vnet.ibm.com>
Tested-by: default avatarChandan Rajendra <chandan@linux.vnet.ibm.com>
Signed-off-by: default avatarOmar Sandoval <osandov@fb.com>
Signed-off-by: default avatarDavid Sterba <dsterba@suse.com>
parent 6675df31
...@@ -273,20 +273,37 @@ static int test_find_delalloc(u32 sectorsize) ...@@ -273,20 +273,37 @@ static int test_find_delalloc(u32 sectorsize)
return ret; return ret;
} }
/** static int check_eb_bitmap(unsigned long *bitmap, struct extent_buffer *eb,
* test_bit_in_byte - Determine whether a bit is set in a byte unsigned long len)
* @nr: bit number to test
* @addr: Address to start counting from
*/
static inline int test_bit_in_byte(int nr, const u8 *addr)
{ {
return 1UL & (addr[nr / BITS_PER_BYTE] >> (nr & (BITS_PER_BYTE - 1))); unsigned long i;
for (i = 0; i < len * BITS_PER_BYTE; i++) {
int bit, bit1;
bit = !!test_bit(i, bitmap);
bit1 = !!extent_buffer_test_bit(eb, 0, i);
if (bit1 != bit) {
test_msg("Bits do not match\n");
return -EINVAL;
}
bit1 = !!extent_buffer_test_bit(eb, i / BITS_PER_BYTE,
i % BITS_PER_BYTE);
if (bit1 != bit) {
test_msg("Offset bits do not match\n");
return -EINVAL;
}
}
return 0;
} }
static int __test_eb_bitmaps(unsigned long *bitmap, struct extent_buffer *eb, static int __test_eb_bitmaps(unsigned long *bitmap, struct extent_buffer *eb,
unsigned long len) unsigned long len)
{ {
unsigned long i, x; unsigned long i, j;
u32 x;
int ret;
memset(bitmap, 0, len); memset(bitmap, 0, len);
memset_extent_buffer(eb, 0, 0, len); memset_extent_buffer(eb, 0, 0, len);
...@@ -297,16 +314,18 @@ static int __test_eb_bitmaps(unsigned long *bitmap, struct extent_buffer *eb, ...@@ -297,16 +314,18 @@ static int __test_eb_bitmaps(unsigned long *bitmap, struct extent_buffer *eb,
bitmap_set(bitmap, 0, len * BITS_PER_BYTE); bitmap_set(bitmap, 0, len * BITS_PER_BYTE);
extent_buffer_bitmap_set(eb, 0, 0, len * BITS_PER_BYTE); extent_buffer_bitmap_set(eb, 0, 0, len * BITS_PER_BYTE);
if (memcmp_extent_buffer(eb, bitmap, 0, len) != 0) { ret = check_eb_bitmap(bitmap, eb, len);
if (ret) {
test_msg("Setting all bits failed\n"); test_msg("Setting all bits failed\n");
return -EINVAL; return ret;
} }
bitmap_clear(bitmap, 0, len * BITS_PER_BYTE); bitmap_clear(bitmap, 0, len * BITS_PER_BYTE);
extent_buffer_bitmap_clear(eb, 0, 0, len * BITS_PER_BYTE); extent_buffer_bitmap_clear(eb, 0, 0, len * BITS_PER_BYTE);
if (memcmp_extent_buffer(eb, bitmap, 0, len) != 0) { ret = check_eb_bitmap(bitmap, eb, len);
if (ret) {
test_msg("Clearing all bits failed\n"); test_msg("Clearing all bits failed\n");
return -EINVAL; return ret;
} }
/* Straddling pages test */ /* Straddling pages test */
...@@ -316,9 +335,10 @@ static int __test_eb_bitmaps(unsigned long *bitmap, struct extent_buffer *eb, ...@@ -316,9 +335,10 @@ static int __test_eb_bitmaps(unsigned long *bitmap, struct extent_buffer *eb,
sizeof(long) * BITS_PER_BYTE); sizeof(long) * BITS_PER_BYTE);
extent_buffer_bitmap_set(eb, PAGE_SIZE - sizeof(long) / 2, 0, extent_buffer_bitmap_set(eb, PAGE_SIZE - sizeof(long) / 2, 0,
sizeof(long) * BITS_PER_BYTE); sizeof(long) * BITS_PER_BYTE);
if (memcmp_extent_buffer(eb, bitmap, 0, len) != 0) { ret = check_eb_bitmap(bitmap, eb, len);
if (ret) {
test_msg("Setting straddling pages failed\n"); test_msg("Setting straddling pages failed\n");
return -EINVAL; return ret;
} }
bitmap_set(bitmap, 0, len * BITS_PER_BYTE); bitmap_set(bitmap, 0, len * BITS_PER_BYTE);
...@@ -328,9 +348,10 @@ static int __test_eb_bitmaps(unsigned long *bitmap, struct extent_buffer *eb, ...@@ -328,9 +348,10 @@ static int __test_eb_bitmaps(unsigned long *bitmap, struct extent_buffer *eb,
extent_buffer_bitmap_set(eb, 0, 0, len * BITS_PER_BYTE); extent_buffer_bitmap_set(eb, 0, 0, len * BITS_PER_BYTE);
extent_buffer_bitmap_clear(eb, PAGE_SIZE - sizeof(long) / 2, 0, extent_buffer_bitmap_clear(eb, PAGE_SIZE - sizeof(long) / 2, 0,
sizeof(long) * BITS_PER_BYTE); sizeof(long) * BITS_PER_BYTE);
if (memcmp_extent_buffer(eb, bitmap, 0, len) != 0) { ret = check_eb_bitmap(bitmap, eb, len);
if (ret) {
test_msg("Clearing straddling pages failed\n"); test_msg("Clearing straddling pages failed\n");
return -EINVAL; return ret;
} }
} }
...@@ -339,28 +360,22 @@ static int __test_eb_bitmaps(unsigned long *bitmap, struct extent_buffer *eb, ...@@ -339,28 +360,22 @@ static int __test_eb_bitmaps(unsigned long *bitmap, struct extent_buffer *eb,
* something repetitive that could miss some hypothetical off-by-n bug. * something repetitive that could miss some hypothetical off-by-n bug.
*/ */
x = 0; x = 0;
for (i = 0; i < len / sizeof(long); i++) { bitmap_clear(bitmap, 0, len * BITS_PER_BYTE);
x = (0x19660dULL * (u64)x + 0x3c6ef35fULL) & 0xffffffffUL; extent_buffer_bitmap_clear(eb, 0, 0, len * BITS_PER_BYTE);
bitmap[i] = x; for (i = 0; i < len * BITS_PER_BYTE / 32; i++) {
} x = (0x19660dULL * (u64)x + 0x3c6ef35fULL) & 0xffffffffU;
write_extent_buffer(eb, bitmap, 0, len); for (j = 0; j < 32; j++) {
if (x & (1U << j)) {
for (i = 0; i < len * BITS_PER_BYTE; i++) { bitmap_set(bitmap, i * 32 + j, 1);
int bit, bit1; extent_buffer_bitmap_set(eb, 0, i * 32 + j, 1);
}
bit = !!test_bit_in_byte(i, (u8 *)bitmap);
bit1 = !!extent_buffer_test_bit(eb, 0, i);
if (bit1 != bit) {
test_msg("Testing bit pattern failed\n");
return -EINVAL;
} }
}
bit1 = !!extent_buffer_test_bit(eb, i / BITS_PER_BYTE, ret = check_eb_bitmap(bitmap, eb, len);
i % BITS_PER_BYTE); if (ret) {
if (bit1 != bit) { test_msg("Random bit pattern failed\n");
test_msg("Testing bit pattern with offset failed\n"); return ret;
return -EINVAL;
}
} }
return 0; return 0;
......
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