[PATCH 6/8] fsx/fsstress: round blocksize properly

Darrick J. Wong
2021-05-12T02:02:17Z

The block sizes reported by stat and DIOINFO aren't required to be
powers of two. This can happen on an XFS filesystem with a realtime
extent size that isn't a power of two; on such filesystems, certain IO
calls will fail due to alignment issues. Fix that by providing rounding
helpers that work for all sizes.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
---
ltp/fsstress.c | 24 ++++++++++++------------
ltp/fsx.c | 22 +++++++++++-----------
src/global.h | 13 +++++++++++++
3 files changed, 36 insertions(+), 23 deletions(-)

diff --git a/ltp/fsstress.c b/ltp/fsstress.c
index e7cd0eae..b4ddf5e2 100644
--- a/ltp/fsstress.c
+++ b/ltp/fsstress.c
@@ -2140,7 +2140,7 @@ do_aio_rw(int opno, long r, int flags)
" fallback to stat()\n",
procid, opno, f.path, st, errno);
diob.d_mem = diob.d_miniosz = stb.st_blksize;
- diob.d_maxiosz = INT_MAX & ~(diob.d_miniosz - 1);
+ diob.d_maxiosz = rounddown_64(INT_MAX, diob.d_miniosz);
}
dio_env = getenv("XFS_DIO_MIN");
if (dio_env)
@@ -2608,7 +2608,7 @@ clonerange_f(

/* Calculate offsets */
len = (random() % FILELEN_MAX) + 1;
- len &= ~(stat1.st_blksize - 1);
+ len = rounddown_64(len, stat1.st_blksize);
if (len == 0)
len = stat1.st_blksize;
if (len > stat1.st_size)
@@ -2620,7 +2620,7 @@ clonerange_f(
else
off1 = (off64_t)(lr % MIN(stat1.st_size - len, MAXFSIZE));
off1 %= maxfsize;
- off1 &= ~(stat1.st_blksize - 1);
+ off1 = rounddown_64(off1, stat1.st_blksize);

/*
* If srcfile == destfile, randomly generate destination ranges
@@ -2631,7 +2631,7 @@ clonerange_f(
lr = ((int64_t)random() << 32) + random();
off2 = (off64_t)(lr % max_off2);
off2 %= maxfsize;
- off2 &= ~(stat2.st_blksize - 1);
+ off2 = rounddown_64(off2, stat2.st_blksize);
} while (stat1.st_ino == stat2.st_ino && llabs(off2 - off1) < len);

/* Clone data blocks */
@@ -2968,7 +2968,7 @@ deduperange_f(

/* Never try to dedupe more than half of the src file. */
len = (random() % FILELEN_MAX) + 1;
- len &= ~(stat[0].st_blksize - 1);
+ len = rounddown_64(len, stat[0].st_blksize);
if (len == 0)
len = stat[0].st_blksize / 2;
if (len > stat[0].st_size / 2)
@@ -2981,7 +2981,7 @@ deduperange_f(
else
off[0] = (off64_t)(lr % MIN(stat[0].st_size - len, MAXFSIZE));
off[0] %= maxfsize;
- off[0] &= ~(stat[0].st_blksize - 1);
+ off[0] = rounddown_64(off[0], stat[0].st_blksize);

/*
* If srcfile == destfile[i], randomly generate destination ranges
@@ -2997,7 +2997,7 @@ deduperange_f(
else
off[i] = (off64_t)(lr % MIN(stat[i].st_size - len, MAXFSIZE));
off[i] %= maxfsize;
- off[i] &= ~(stat[i].st_blksize - 1);
+ off[i] = rounddown_64(off[i], stat[i].st_blksize);
} while (stat[0].st_ino == stat[i].st_ino &&
llabs(off[i] - off[0]) < len &&
tries++ < 10);
@@ -3406,7 +3406,7 @@ dread_f(int opno, long r)
" fallback to stat()\n",
procid, opno, f.path, st, errno);
diob.d_mem = diob.d_miniosz = stb.st_blksize;
- diob.d_maxiosz = INT_MAX & ~(diob.d_miniosz - 1);
+ diob.d_maxiosz = rounddown_64(INT_MAX, diob.d_miniosz);
}

dio_env = getenv("XFS_DIO_MIN");
@@ -3483,7 +3483,7 @@ dwrite_f(int opno, long r)
" %s%s return %d, fallback to stat()\n",
procid, opno, f.path, st, errno);
diob.d_mem = diob.d_miniosz = stb.st_blksize;
- diob.d_maxiosz = INT_MAX & ~(diob.d_miniosz - 1);
+ diob.d_maxiosz = rounddown_64(INT_MAX, diob.d_miniosz);
}

dio_env = getenv("XFS_DIO_MIN");
@@ -3579,8 +3579,8 @@ do_fallocate(int opno, long r, int mode)
*/
if ((mode & (FALLOC_FL_COLLAPSE_RANGE | FALLOC_FL_INSERT_RANGE)) &&
(opno % 2)) {
- off = ((off + stb.st_blksize - 1) & ~(stb.st_blksize - 1));
- len = ((len + stb.st_blksize - 1) & ~(stb.st_blksize - 1));
+ off = roundup_64(off, stb.st_blksize);
+ len = roundup_64(len, stb.st_blksize);
}
mode |= FALLOC_FL_KEEP_SIZE & random();
e = fallocate(fd, mode, (loff_t)off, (loff_t)len) < 0 ? errno : 0;
@@ -4186,7 +4186,7 @@ do_mmap(int opno, long r, int prot)

lr = ((int64_t)random() << 32) + random();
off = (off64_t)(lr % stb.st_size);
- off &= (off64_t)(~(sysconf(_SC_PAGE_SIZE) - 1));
+ off = rounddown_64(off, sysconf(_SC_PAGE_SIZE));
len = (size_t)(random() % MIN(stb.st_size - off, FILELEN_MAX)) + 1;

flags = (random() % 2) ? MAP_SHARED : MAP_PRIVATE;
diff --git a/ltp/fsx.c b/ltp/fsx.c
index cd0bae55..16e75c40 100644
--- a/ltp/fsx.c
+++ b/ltp/fsx.c
@@ -203,7 +203,7 @@ static void *round_ptr_up(void *ptr, unsigned long align, unsigned long offset)
{
unsigned long ret = (unsigned long)ptr;

- ret = ((ret + align - 1) & ~(align - 1));
+ ret = roundup_64(ret, align);
ret += offset;
return (void *)ret;
}
@@ -1948,12 +1948,12 @@ static void generate_dest_range(bool bdy_align,

TRIM_OFF_LEN(*src_offset, *size, file_size);
if (bdy_align) {
- *src_offset -= *src_offset % readbdy;
+ *src_offset = rounddown_64(*src_offset, readbdy);
if (o_direct)
- *size -= *size % readbdy;
+ *size = rounddown_64(*size, readbdy);
} else {
- *src_offset = *src_offset & ~(block_size - 1);
- *size = *size & ~(block_size - 1);
+ *src_offset = rounddown_64(*src_offset, block_size);
+ *size = rounddown_64(*size, block_size);
}

do {
@@ -1964,9 +1964,9 @@ static void generate_dest_range(bool bdy_align,
*dst_offset = random();
TRIM_OFF(*dst_offset, max_range_end);
if (bdy_align)
- *dst_offset -= *dst_offset % writebdy;
+ *dst_offset = rounddown_64(*dst_offset, writebdy);
else
- *dst_offset = *dst_offset & ~(block_size - 1);
+ *dst_offset = rounddown_64(*dst_offset, block_size);
} while (range_overlaps(*src_offset, *dst_offset, *size) ||
*dst_offset + *size > max_range_end);
}
@@ -2156,8 +2156,8 @@ test(void)
break;
case OP_COLLAPSE_RANGE:
TRIM_OFF_LEN(offset, size, file_size - 1);
- offset = offset & ~(block_size - 1);
- size = size & ~(block_size - 1);
+ offset = rounddown_64(offset, block_size);
+ size = rounddown_64(size, block_size);
if (size == 0) {
log4(OP_COLLAPSE_RANGE, offset, size, FL_SKIPPED);
goto out;
@@ -2167,8 +2167,8 @@ test(void)
case OP_INSERT_RANGE:
TRIM_OFF(offset, file_size);
TRIM_LEN(file_size, size, maxfilelen);
- offset = offset & ~(block_size - 1);
- size = size & ~(block_size - 1);
+ offset = rounddown_64(offset, block_size);
+ size = rounddown_64(size, block_size);
if (size == 0) {
log4(OP_INSERT_RANGE, offset, size, FL_SKIPPED);
goto out;
diff --git a/src/global.h b/src/global.h
index e5e46234..b4407099 100644
--- a/src/global.h
+++ b/src/global.h
@@ -171,4 +171,17 @@
#include <sys/mman.h>
#endif

+static inline unsigned long long
+rounddown_64(unsigned long long x, unsigned int y)
+{
+ x /= y;
+ return x * y;
+}
+
+static inline unsigned long long
+roundup_64(unsigned long long x, unsigned int y)
+{
+ return rounddown_64(x + y - 1, y);
+}
+
#endif /* GLOBAL_H */