mirror of https://github.com/xemu-project/xemu.git
Block patches for 2.2.0-rc2
-----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIcBAABAgAGBQJUay5nAAoJEH8JsnLIjy/W7RQQAMUko37jld+dpqybxm8Vc1AL bKIlieyjcOTj6CeUvlb0bjS6Kg4Mg4LOEopv5g7fjTLn4V5ZtPBO3+AKcxOGmMpp 2O1pCo+CBe+q29YV0HIx+t+3HCQInz31GZlAnXa2FkHk/urdFHW7IWSljkLULOKe V6WnHoX87ZyP41aNJD5nsXza7cF0Z2DiyLYiAAJnZqpXS8aaLlS9IC2qEbfR3mjS X8gVbpUotjfBLu0XjqwuVtZXuUvnY2PJWXaYK8DFKzx/LXwtD2Ynz08bVAL06KMB ERRHF4HSY7weJV3t/r+mE0JfOpqxCbOcfO1eHhQGlqXxvoTVDRNS/fsrYrs62N8I L7R4NHeqDFm0mx2FLVjmrZb90KpwciLoum8IgJlFipotJOlhESxrNYqh3rjgJaQ7 51N6ApywK6RjZfDFbPrD7PeYl4rilxno0BgAfw+SKlNTAE3htoQvoeigMgnOzrMN 4W/eiO8GHK1ll+24Rmbf6ZRAkowwJzCfvugoi5zfTpmy0awJU+tOEpB8zH9Ayqaw kIADrMUXEgitwwwVj4j5629zGbKydxNFjVlysSiyTHECGCoQPcwS38Eb76f0TA+i barcC/SRY2ls7skbVWEDMqWoI/kk0xz4I1nF8YSscGbul3d6WfBf9VJbm/+gsbIz JA9UXVtTEJqR6WyYuEK/ =9y58 -----END PGP SIGNATURE----- Merge remote-tracking branch 'remotes/kevin/tags/for-upstream' into staging Block patches for 2.2.0-rc2 # gpg: Signature made Tue 18 Nov 2014 11:32:55 GMT using RSA key ID C88F2FD6 # gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" * remotes/kevin/tags/for-upstream: block/raw-posix: Catch fsync() errors block/raw-posix: Only sync after successful preallocation block/raw-posix: Fix preallocating write() loop raw-posix: The SEEK_HOLE code is flawed, rewrite it raw-posix: SEEK_HOLE suffices, get rid of FIEMAP raw-posix: Fix comment for raw_co_get_block_status() Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
This commit is contained in:
Peter Maydell
commit
1ab8f867ef
|
|
@ -60,9 +60,6 @@
|
|||
#define FS_NOCOW_FL 0x00800000 /* Do not cow file */
|
||||
#endif
|
||||
#endif
|
||||
#ifdef CONFIG_FIEMAP
|
||||
#include <linux/fiemap.h>
|
||||
#endif
|
||||
#ifdef CONFIG_FALLOCATE_PUNCH_HOLE
|
||||
#include <linux/falloc.h>
|
||||
#endif
|
||||
|
|
@ -151,9 +148,6 @@ typedef struct BDRVRawState {
|
|||
bool has_write_zeroes:1;
|
||||
bool discard_zeroes:1;
|
||||
bool needs_alignment;
|
||||
#ifdef CONFIG_FIEMAP
|
||||
bool skip_fiemap;
|
||||
#endif
|
||||
} BDRVRawState;
|
||||
|
||||
typedef struct BDRVRawReopenState {
|
||||
|
|
@ -1457,9 +1451,16 @@ static int raw_create(const char *filename, QemuOpts *opts, Error **errp)
|
|||
"Could not write to the new file");
|
||||
break;
|
||||
}
|
||||
left -= num;
|
||||
left -= result;
|
||||
}
|
||||
if (result >= 0) {
|
||||
result = fsync(fd);
|
||||
if (result < 0) {
|
||||
result = -errno;
|
||||
error_setg_errno(errp, -result,
|
||||
"Could not flush new file to disk");
|
||||
}
|
||||
}
|
||||
fsync(fd);
|
||||
g_free(buf);
|
||||
break;
|
||||
}
|
||||
|
|
@ -1481,83 +1482,93 @@ out:
|
|||
return result;
|
||||
}
|
||||
|
||||
static int try_fiemap(BlockDriverState *bs, off_t start, off_t *data,
|
||||
off_t *hole, int nb_sectors)
|
||||
{
|
||||
#ifdef CONFIG_FIEMAP
|
||||
BDRVRawState *s = bs->opaque;
|
||||
int ret = 0;
|
||||
struct {
|
||||
struct fiemap fm;
|
||||
struct fiemap_extent fe;
|
||||
} f;
|
||||
|
||||
if (s->skip_fiemap) {
|
||||
return -ENOTSUP;
|
||||
}
|
||||
|
||||
f.fm.fm_start = start;
|
||||
f.fm.fm_length = (int64_t)nb_sectors * BDRV_SECTOR_SIZE;
|
||||
f.fm.fm_flags = FIEMAP_FLAG_SYNC;
|
||||
f.fm.fm_extent_count = 1;
|
||||
f.fm.fm_reserved = 0;
|
||||
if (ioctl(s->fd, FS_IOC_FIEMAP, &f) == -1) {
|
||||
s->skip_fiemap = true;
|
||||
return -errno;
|
||||
}
|
||||
|
||||
if (f.fm.fm_mapped_extents == 0) {
|
||||
/* No extents found, data is beyond f.fm.fm_start + f.fm.fm_length.
|
||||
* f.fm.fm_start + f.fm.fm_length must be clamped to the file size!
|
||||
*/
|
||||
off_t length = lseek(s->fd, 0, SEEK_END);
|
||||
*hole = f.fm.fm_start;
|
||||
*data = MIN(f.fm.fm_start + f.fm.fm_length, length);
|
||||
} else {
|
||||
*data = f.fe.fe_logical;
|
||||
*hole = f.fe.fe_logical + f.fe.fe_length;
|
||||
if (f.fe.fe_flags & FIEMAP_EXTENT_UNWRITTEN) {
|
||||
ret |= BDRV_BLOCK_ZERO;
|
||||
}
|
||||
}
|
||||
|
||||
return ret;
|
||||
#else
|
||||
return -ENOTSUP;
|
||||
#endif
|
||||
}
|
||||
|
||||
static int try_seek_hole(BlockDriverState *bs, off_t start, off_t *data,
|
||||
off_t *hole)
|
||||
/*
|
||||
* Find allocation range in @bs around offset @start.
|
||||
* May change underlying file descriptor's file offset.
|
||||
* If @start is not in a hole, store @start in @data, and the
|
||||
* beginning of the next hole in @hole, and return 0.
|
||||
* If @start is in a non-trailing hole, store @start in @hole and the
|
||||
* beginning of the next non-hole in @data, and return 0.
|
||||
* If @start is in a trailing hole or beyond EOF, return -ENXIO.
|
||||
* If we can't find out, return a negative errno other than -ENXIO.
|
||||
*/
|
||||
static int find_allocation(BlockDriverState *bs, off_t start,
|
||||
off_t *data, off_t *hole)
|
||||
{
|
||||
#if defined SEEK_HOLE && defined SEEK_DATA
|
||||
BDRVRawState *s = bs->opaque;
|
||||
off_t offs;
|
||||
|
||||
*hole = lseek(s->fd, start, SEEK_HOLE);
|
||||
if (*hole == -1) {
|
||||
return -errno;
|
||||
/*
|
||||
* SEEK_DATA cases:
|
||||
* D1. offs == start: start is in data
|
||||
* D2. offs > start: start is in a hole, next data at offs
|
||||
* D3. offs < 0, errno = ENXIO: either start is in a trailing hole
|
||||
* or start is beyond EOF
|
||||
* If the latter happens, the file has been truncated behind
|
||||
* our back since we opened it. All bets are off then.
|
||||
* Treating like a trailing hole is simplest.
|
||||
* D4. offs < 0, errno != ENXIO: we learned nothing
|
||||
*/
|
||||
offs = lseek(s->fd, start, SEEK_DATA);
|
||||
if (offs < 0) {
|
||||
return -errno; /* D3 or D4 */
|
||||
}
|
||||
assert(offs >= start);
|
||||
|
||||
if (offs > start) {
|
||||
/* D2: in hole, next data at offs */
|
||||
*hole = start;
|
||||
*data = offs;
|
||||
return 0;
|
||||
}
|
||||
|
||||
if (*hole > start) {
|
||||
/* D1: in data, end not yet known */
|
||||
|
||||
/*
|
||||
* SEEK_HOLE cases:
|
||||
* H1. offs == start: start is in a hole
|
||||
* If this happens here, a hole has been dug behind our back
|
||||
* since the previous lseek().
|
||||
* H2. offs > start: either start is in data, next hole at offs,
|
||||
* or start is in trailing hole, EOF at offs
|
||||
* Linux treats trailing holes like any other hole: offs ==
|
||||
* start. Solaris seeks to EOF instead: offs > start (blech).
|
||||
* If that happens here, a hole has been dug behind our back
|
||||
* since the previous lseek().
|
||||
* H3. offs < 0, errno = ENXIO: start is beyond EOF
|
||||
* If this happens, the file has been truncated behind our
|
||||
* back since we opened it. Treat it like a trailing hole.
|
||||
* H4. offs < 0, errno != ENXIO: we learned nothing
|
||||
* Pretend we know nothing at all, i.e. "forget" about D1.
|
||||
*/
|
||||
offs = lseek(s->fd, start, SEEK_HOLE);
|
||||
if (offs < 0) {
|
||||
return -errno; /* D1 and (H3 or H4) */
|
||||
}
|
||||
assert(offs >= start);
|
||||
|
||||
if (offs > start) {
|
||||
/*
|
||||
* D1 and H2: either in data, next hole at offs, or it was in
|
||||
* data but is now in a trailing hole. In the latter case,
|
||||
* all bets are off. Treating it as if it there was data all
|
||||
* the way to EOF is safe, so simply do that.
|
||||
*/
|
||||
*data = start;
|
||||
} else {
|
||||
/* On a hole. We need another syscall to find its end. */
|
||||
*data = lseek(s->fd, start, SEEK_DATA);
|
||||
if (*data == -1) {
|
||||
*data = lseek(s->fd, 0, SEEK_END);
|
||||
}
|
||||
*hole = offs;
|
||||
return 0;
|
||||
}
|
||||
|
||||
return 0;
|
||||
/* D1 and H1 */
|
||||
return -EBUSY;
|
||||
#else
|
||||
return -ENOTSUP;
|
||||
#endif
|
||||
}
|
||||
|
||||
/*
|
||||
* Returns true iff the specified sector is present in the disk image. Drivers
|
||||
* not implementing the functionality are assumed to not support backing files,
|
||||
* hence all their sectors are reported as allocated.
|
||||
* Returns the allocation status of the specified sectors.
|
||||
*
|
||||
* If 'sector_num' is beyond the end of the disk image the return value is 0
|
||||
* and 'pnum' is set to 0.
|
||||
|
|
@ -1593,28 +1604,26 @@ static int64_t coroutine_fn raw_co_get_block_status(BlockDriverState *bs,
|
|||
nb_sectors = DIV_ROUND_UP(total_size - start, BDRV_SECTOR_SIZE);
|
||||
}
|
||||
|
||||
ret = try_seek_hole(bs, start, &data, &hole);
|
||||
if (ret < 0) {
|
||||
ret = try_fiemap(bs, start, &data, &hole, nb_sectors);
|
||||
if (ret < 0) {
|
||||
/* Assume everything is allocated. */
|
||||
data = 0;
|
||||
hole = start + nb_sectors * BDRV_SECTOR_SIZE;
|
||||
ret = 0;
|
||||
}
|
||||
}
|
||||
|
||||
assert(ret >= 0);
|
||||
|
||||
if (data <= start) {
|
||||
ret = find_allocation(bs, start, &data, &hole);
|
||||
if (ret == -ENXIO) {
|
||||
/* Trailing hole */
|
||||
*pnum = nb_sectors;
|
||||
ret = BDRV_BLOCK_ZERO;
|
||||
} else if (ret < 0) {
|
||||
/* No info available, so pretend there are no holes */
|
||||
*pnum = nb_sectors;
|
||||
ret = BDRV_BLOCK_DATA;
|
||||
} else if (data == start) {
|
||||
/* On a data extent, compute sectors to the end of the extent. */
|
||||
*pnum = MIN(nb_sectors, (hole - start) / BDRV_SECTOR_SIZE);
|
||||
return ret | BDRV_BLOCK_DATA | BDRV_BLOCK_OFFSET_VALID | start;
|
||||
ret = BDRV_BLOCK_DATA;
|
||||
} else {
|
||||
/* On a hole, compute sectors to the beginning of the next extent. */
|
||||
assert(hole == start);
|
||||
*pnum = MIN(nb_sectors, (data - start) / BDRV_SECTOR_SIZE);
|
||||
return ret | BDRV_BLOCK_ZERO | BDRV_BLOCK_OFFSET_VALID | start;
|
||||
ret = BDRV_BLOCK_ZERO;
|
||||
}
|
||||
return ret | BDRV_BLOCK_OFFSET_VALID | start;
|
||||
}
|
||||
|
||||
static coroutine_fn BlockAIOCB *raw_aio_discard(BlockDriverState *bs,
|
||||
|
|
|
|||
Loading…
Reference in New Issue