diff options
| -rw-r--r-- | block.c | 8 | ||||
| -rw-r--r-- | block/io.c | 2 | ||||
| -rw-r--r-- | block/raw-posix.c | 13 |
3 files changed, 12 insertions, 11 deletions
@@ -106,8 +106,8 @@ int is_windows_drive(const char *filename) size_t bdrv_opt_mem_align(BlockDriverState *bs) { if (!bs || !bs->drv) { - /* 4k should be on the safe side */ - return 4096; + /* page size or 4k (hdd sector size) should be on the safe side */ + return MAX(4096, getpagesize()); } return bs->bl.opt_mem_alignment; @@ -116,8 +116,8 @@ size_t bdrv_opt_mem_align(BlockDriverState *bs) size_t bdrv_min_mem_align(BlockDriverState *bs) { if (!bs || !bs->drv) { - /* 4k should be on the safe side */ - return 4096; + /* page size or 4k (hdd sector size) should be on the safe side */ + return MAX(4096, getpagesize()); } return bs->bl.min_mem_alignment; diff --git a/block/io.c b/block/io.c index e6c363921d..b3ea95c74f 100644 --- a/block/io.c +++ b/block/io.c @@ -205,7 +205,7 @@ void bdrv_refresh_limits(BlockDriverState *bs, Error **errp) bs->bl.opt_mem_alignment = bs->file->bl.opt_mem_alignment; } else { bs->bl.min_mem_alignment = 512; - bs->bl.opt_mem_alignment = 512; + bs->bl.opt_mem_alignment = getpagesize(); } if (bs->backing_hd) { diff --git a/block/raw-posix.c b/block/raw-posix.c index 70839245fd..2990e954ae 100644 --- a/block/raw-posix.c +++ b/block/raw-posix.c @@ -301,6 +301,7 @@ static void raw_probe_alignment(BlockDriverState *bs, int fd, Error **errp) { BDRVRawState *s = bs->opaque; char *buf; + size_t max_align = MAX(MAX_BLOCKSIZE, getpagesize()); /* For /dev/sg devices the alignment is not really used. With buffered I/O, we don't have any restrictions. */ @@ -330,9 +331,9 @@ static void raw_probe_alignment(BlockDriverState *bs, int fd, Error **errp) /* If we could not get the sizes so far, we can only guess them */ if (!s->buf_align) { size_t align; - buf = qemu_memalign(MAX_BLOCKSIZE, 2 * MAX_BLOCKSIZE); - for (align = 512; align <= MAX_BLOCKSIZE; align <<= 1) { - if (raw_is_io_aligned(fd, buf + align, MAX_BLOCKSIZE)) { + buf = qemu_memalign(max_align, 2 * max_align); + for (align = 512; align <= max_align; align <<= 1) { + if (raw_is_io_aligned(fd, buf + align, max_align)) { s->buf_align = align; break; } @@ -342,8 +343,8 @@ static void raw_probe_alignment(BlockDriverState *bs, int fd, Error **errp) if (!bs->request_alignment) { size_t align; - buf = qemu_memalign(s->buf_align, MAX_BLOCKSIZE); - for (align = 512; align <= MAX_BLOCKSIZE; align <<= 1) { + buf = qemu_memalign(s->buf_align, max_align); + for (align = 512; align <= max_align; align <<= 1) { if (raw_is_io_aligned(fd, buf, align)) { bs->request_alignment = align; break; @@ -726,7 +727,7 @@ static void raw_refresh_limits(BlockDriverState *bs, Error **errp) raw_probe_alignment(bs, s->fd, errp); bs->bl.min_mem_alignment = s->buf_align; - bs->bl.opt_mem_alignment = s->buf_align; + bs->bl.opt_mem_alignment = MAX(s->buf_align, getpagesize()); } static int check_for_dasd(int fd) |