* See the COPYING file in the top-level directory.
*
*/
+#include "qemu/osdep.h"
#include <glusterfs/api/glfs.h>
#include "block/block_int.h"
+#include "qapi/error.h"
#include "qemu/uri.h"
typedef struct GlusterAIOCB {
typedef struct BDRVGlusterState {
struct glfs *glfs;
struct glfs_fd *fd;
+ bool supports_seek_data;
+ int debug_level;
} BDRVGlusterState;
typedef struct GlusterConf {
char *volname;
char *image;
char *transport;
+ int debug_level;
} GlusterConf;
static void qemu_gluster_gconf_free(GlusterConf *gconf)
goto out;
}
- /*
- * TODO: Use GF_LOG_ERROR instead of hard code value of 4 here when
- * GlusterFS makes GF_LOG_* macros available to libgfapi users.
- */
- ret = glfs_set_logging(glfs, "-", 4);
+ ret = glfs_set_logging(glfs, "-", gconf->debug_level);
if (ret < 0) {
goto out;
}
if (!ret || ret == acb->size) {
acb->ret = 0; /* Success */
} else if (ret < 0) {
- acb->ret = ret; /* Read/Write failed */
+ acb->ret = -errno; /* Read/Write failed */
} else {
acb->ret = -EIO; /* Partial read/write - fail it */
}
qemu_bh_schedule(acb->bh);
}
+#define GLUSTER_OPT_FILENAME "filename"
+#define GLUSTER_OPT_DEBUG "debug"
+#define GLUSTER_DEBUG_DEFAULT 4
+#define GLUSTER_DEBUG_MAX 9
+
/* TODO Convert to fine grained options */
static QemuOptsList runtime_opts = {
.name = "gluster",
.head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
.desc = {
{
- .name = "filename",
+ .name = GLUSTER_OPT_FILENAME,
.type = QEMU_OPT_STRING,
.help = "URL to the gluster image",
},
+ {
+ .name = GLUSTER_OPT_DEBUG,
+ .type = QEMU_OPT_NUMBER,
+ .help = "Gluster log level, valid range is 0-9",
+ },
{ /* end of list */ }
},
};
}
}
+/*
+ * Do SEEK_DATA/HOLE to detect if it is functional. Older broken versions of
+ * gfapi incorrectly return the current offset when SEEK_DATA/HOLE is used.
+ * - Corrected versions return -1 and set errno to EINVAL.
+ * - Versions that support SEEK_DATA/HOLE correctly, will return -1 and set
+ * errno to ENXIO when SEEK_DATA is called with a position of EOF.
+ */
+static bool qemu_gluster_test_seek(struct glfs_fd *fd)
+{
+ off_t ret, eof;
+
+ eof = glfs_lseek(fd, 0, SEEK_END);
+ if (eof < 0) {
+ /* this should never occur */
+ return false;
+ }
+
+ /* this should always fail with ENXIO if SEEK_DATA is supported */
+ ret = glfs_lseek(fd, eof, SEEK_DATA);
+ return (ret < 0) && (errno == ENXIO);
+}
+
static int qemu_gluster_open(BlockDriverState *bs, QDict *options,
int bdrv_flags, Error **errp)
{
goto out;
}
- filename = qemu_opt_get(opts, "filename");
+ filename = qemu_opt_get(opts, GLUSTER_OPT_FILENAME);
+
+ s->debug_level = qemu_opt_get_number(opts, GLUSTER_OPT_DEBUG,
+ GLUSTER_DEBUG_DEFAULT);
+ if (s->debug_level < 0) {
+ s->debug_level = 0;
+ } else if (s->debug_level > GLUSTER_DEBUG_MAX) {
+ s->debug_level = GLUSTER_DEBUG_MAX;
+ }
+ gconf->debug_level = s->debug_level;
s->glfs = qemu_gluster_init(gconf, filename, errp);
if (!s->glfs) {
ret = -errno;
goto out;
}
+#ifdef CONFIG_GLUSTERFS_XLATOR_OPT
+ /* Without this, if fsync fails for a recoverable reason (for instance,
+ * ENOSPC), gluster will dump its cache, preventing retries. This means
+ * almost certain data loss. Not all gluster versions support the
+ * 'resync-failed-syncs-after-fsync' key value, but there is no way to
+ * discover during runtime if it is supported (this api returns success for
+ * unknown key/value pairs) */
+ ret = glfs_set_xlator_option(s->glfs, "*-write-behind",
+ "resync-failed-syncs-after-fsync",
+ "on");
+ if (ret < 0) {
+ error_setg_errno(errp, errno, "Unable to set xlator key/value pair");
+ ret = -errno;
+ goto out;
+ }
+#endif
+
qemu_gluster_parse_flags(bdrv_flags, &open_flags);
s->fd = glfs_open(s->glfs, gconf->image, open_flags);
ret = -errno;
}
+ s->supports_seek_data = qemu_gluster_test_seek(s->fd);
+
out:
qemu_opts_del(opts);
qemu_gluster_gconf_free(gconf);
BlockReopenQueue *queue, Error **errp)
{
int ret = 0;
+ BDRVGlusterState *s;
BDRVGlusterReopenState *reop_s;
GlusterConf *gconf = NULL;
int open_flags = 0;
assert(state != NULL);
assert(state->bs != NULL);
+ s = state->bs->opaque;
+
state->opaque = g_new0(BDRVGlusterReopenState, 1);
reop_s = state->opaque;
gconf = g_new0(GlusterConf, 1);
+ gconf->debug_level = s->debug_level;
reop_s->glfs = qemu_gluster_init(gconf, state->bs->filename, errp);
if (reop_s->glfs == NULL) {
ret = -errno;
goto exit;
}
+#ifdef CONFIG_GLUSTERFS_XLATOR_OPT
+ ret = glfs_set_xlator_option(reop_s->glfs, "*-write-behind",
+ "resync-failed-syncs-after-fsync", "on");
+ if (ret < 0) {
+ error_setg_errno(errp, errno, "Unable to set xlator key/value pair");
+ ret = -errno;
+ goto exit;
+ }
+#endif
+
reop_s->fd = glfs_open(reop_s->glfs, gconf->image, open_flags);
if (reop_s->fd == NULL) {
/* reops->glfs will be cleaned up in _abort */
}
#ifdef CONFIG_GLUSTERFS_ZEROFILL
-static coroutine_fn int qemu_gluster_co_write_zeroes(BlockDriverState *bs,
- int64_t sector_num, int nb_sectors, BdrvRequestFlags flags)
+static coroutine_fn int qemu_gluster_co_pwrite_zeroes(BlockDriverState *bs,
+ int64_t offset, int size, BdrvRequestFlags flags)
{
int ret;
- GlusterAIOCB *acb = g_slice_new(GlusterAIOCB);
+ GlusterAIOCB acb;
BDRVGlusterState *s = bs->opaque;
- off_t size = nb_sectors * BDRV_SECTOR_SIZE;
- off_t offset = sector_num * BDRV_SECTOR_SIZE;
- acb->size = size;
- acb->ret = 0;
- acb->coroutine = qemu_coroutine_self();
- acb->aio_context = bdrv_get_aio_context(bs);
+ acb.size = size;
+ acb.ret = 0;
+ acb.coroutine = qemu_coroutine_self();
+ acb.aio_context = bdrv_get_aio_context(bs);
- ret = glfs_zerofill_async(s->fd, offset, size, &gluster_finish_aiocb, acb);
+ ret = glfs_zerofill_async(s->fd, offset, size, gluster_finish_aiocb, &acb);
if (ret < 0) {
- ret = -errno;
- goto out;
+ return -errno;
}
qemu_coroutine_yield();
- ret = acb->ret;
-
-out:
- g_slice_free(GlusterAIOCB, acb);
- return ret;
+ return acb.ret;
}
static inline bool gluster_supports_zerofill(void)
char *tmp = NULL;
GlusterConf *gconf = g_new0(GlusterConf, 1);
+ gconf->debug_level = qemu_opt_get_number_del(opts, GLUSTER_OPT_DEBUG,
+ GLUSTER_DEBUG_DEFAULT);
+ if (gconf->debug_level < 0) {
+ gconf->debug_level = 0;
+ } else if (gconf->debug_level > GLUSTER_DEBUG_MAX) {
+ gconf->debug_level = GLUSTER_DEBUG_MAX;
+ }
+
glfs = qemu_gluster_init(gconf, filename, errp);
if (!glfs) {
ret = -errno;
int64_t sector_num, int nb_sectors, QEMUIOVector *qiov, int write)
{
int ret;
- GlusterAIOCB *acb = g_slice_new(GlusterAIOCB);
+ GlusterAIOCB acb;
BDRVGlusterState *s = bs->opaque;
size_t size = nb_sectors * BDRV_SECTOR_SIZE;
off_t offset = sector_num * BDRV_SECTOR_SIZE;
- acb->size = size;
- acb->ret = 0;
- acb->coroutine = qemu_coroutine_self();
- acb->aio_context = bdrv_get_aio_context(bs);
+ acb.size = size;
+ acb.ret = 0;
+ acb.coroutine = qemu_coroutine_self();
+ acb.aio_context = bdrv_get_aio_context(bs);
if (write) {
ret = glfs_pwritev_async(s->fd, qiov->iov, qiov->niov, offset, 0,
- &gluster_finish_aiocb, acb);
+ gluster_finish_aiocb, &acb);
} else {
ret = glfs_preadv_async(s->fd, qiov->iov, qiov->niov, offset, 0,
- &gluster_finish_aiocb, acb);
+ gluster_finish_aiocb, &acb);
}
if (ret < 0) {
- ret = -errno;
- goto out;
+ return -errno;
}
qemu_coroutine_yield();
- ret = acb->ret;
-
-out:
- g_slice_free(GlusterAIOCB, acb);
- return ret;
+ return acb.ret;
}
static int qemu_gluster_truncate(BlockDriverState *bs, int64_t offset)
return qemu_gluster_co_rw(bs, sector_num, nb_sectors, qiov, 1);
}
+static void qemu_gluster_close(BlockDriverState *bs)
+{
+ BDRVGlusterState *s = bs->opaque;
+
+ if (s->fd) {
+ glfs_close(s->fd);
+ s->fd = NULL;
+ }
+ glfs_fini(s->glfs);
+}
+
static coroutine_fn int qemu_gluster_co_flush_to_disk(BlockDriverState *bs)
{
int ret;
- GlusterAIOCB *acb = g_slice_new(GlusterAIOCB);
+ GlusterAIOCB acb;
BDRVGlusterState *s = bs->opaque;
- acb->size = 0;
- acb->ret = 0;
- acb->coroutine = qemu_coroutine_self();
- acb->aio_context = bdrv_get_aio_context(bs);
+ acb.size = 0;
+ acb.ret = 0;
+ acb.coroutine = qemu_coroutine_self();
+ acb.aio_context = bdrv_get_aio_context(bs);
- ret = glfs_fsync_async(s->fd, &gluster_finish_aiocb, acb);
+ ret = glfs_fsync_async(s->fd, gluster_finish_aiocb, &acb);
if (ret < 0) {
ret = -errno;
- goto out;
+ goto error;
}
qemu_coroutine_yield();
- ret = acb->ret;
+ if (acb.ret < 0) {
+ ret = acb.ret;
+ goto error;
+ }
-out:
- g_slice_free(GlusterAIOCB, acb);
+ return acb.ret;
+
+error:
+ /* Some versions of Gluster (3.5.6 -> 3.5.8?) will not retain its cache
+ * after a fsync failure, so we have no way of allowing the guest to safely
+ * continue. Gluster versions prior to 3.5.6 don't retain the cache
+ * either, but will invalidate the fd on error, so this is again our only
+ * option.
+ *
+ * The 'resync-failed-syncs-after-fsync' xlator option for the
+ * write-behind cache will cause later gluster versions to retain its
+ * cache after error, so long as the fd remains open. However, we
+ * currently have no way of knowing if this option is supported.
+ *
+ * TODO: Once gluster provides a way for us to determine if the option
+ * is supported, bypass the closure and setting drv to NULL. */
+ qemu_gluster_close(bs);
+ bs->drv = NULL;
return ret;
}
int64_t sector_num, int nb_sectors)
{
int ret;
- GlusterAIOCB *acb = g_slice_new(GlusterAIOCB);
+ GlusterAIOCB acb;
BDRVGlusterState *s = bs->opaque;
size_t size = nb_sectors * BDRV_SECTOR_SIZE;
off_t offset = sector_num * BDRV_SECTOR_SIZE;
- acb->size = 0;
- acb->ret = 0;
- acb->coroutine = qemu_coroutine_self();
- acb->aio_context = bdrv_get_aio_context(bs);
+ acb.size = 0;
+ acb.ret = 0;
+ acb.coroutine = qemu_coroutine_self();
+ acb.aio_context = bdrv_get_aio_context(bs);
- ret = glfs_discard_async(s->fd, offset, size, &gluster_finish_aiocb, acb);
+ ret = glfs_discard_async(s->fd, offset, size, gluster_finish_aiocb, &acb);
if (ret < 0) {
- ret = -errno;
- goto out;
+ return -errno;
}
qemu_coroutine_yield();
- ret = acb->ret;
-
-out:
- g_slice_free(GlusterAIOCB, acb);
- return ret;
+ return acb.ret;
}
#endif
}
}
-static void qemu_gluster_close(BlockDriverState *bs)
+static int qemu_gluster_has_zero_init(BlockDriverState *bs)
+{
+ /* GlusterFS volume could be backed by a block device */
+ return 0;
+}
+
+/*
+ * 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.
+ *
+ * (Shamefully copied from raw-posix.c, only miniscule adaptions.)
+ */
+static int find_allocation(BlockDriverState *bs, off_t start,
+ off_t *data, off_t *hole)
{
BDRVGlusterState *s = bs->opaque;
+ off_t offs;
- if (s->fd) {
- glfs_close(s->fd);
- s->fd = NULL;
+ if (!s->supports_seek_data) {
+ return -ENOTSUP;
}
- glfs_fini(s->glfs);
+
+ /*
+ * 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 = glfs_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;
+ }
+
+ /* 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 = glfs_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;
+ *hole = offs;
+ return 0;
+ }
+
+ /* D1 and H1 */
+ return -EBUSY;
}
-static int qemu_gluster_has_zero_init(BlockDriverState *bs)
+/*
+ * 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.
+ *
+ * 'pnum' is set to the number of sectors (including and immediately following
+ * the specified sector) that are known to be in the same
+ * allocated/unallocated state.
+ *
+ * 'nb_sectors' is the max value 'pnum' should be set to. If nb_sectors goes
+ * beyond the end of the disk image it will be clamped.
+ *
+ * (Based on raw_co_get_block_status() from raw-posix.c.)
+ */
+static int64_t coroutine_fn qemu_gluster_co_get_block_status(
+ BlockDriverState *bs, int64_t sector_num, int nb_sectors, int *pnum,
+ BlockDriverState **file)
{
- /* GlusterFS volume could be backed by a block device */
- return 0;
+ BDRVGlusterState *s = bs->opaque;
+ off_t start, data = 0, hole = 0;
+ int64_t total_size;
+ int ret = -EINVAL;
+
+ if (!s->fd) {
+ return ret;
+ }
+
+ start = sector_num * BDRV_SECTOR_SIZE;
+ total_size = bdrv_getlength(bs);
+ if (total_size < 0) {
+ return total_size;
+ } else if (start >= total_size) {
+ *pnum = 0;
+ return 0;
+ } else if (start + nb_sectors * BDRV_SECTOR_SIZE > total_size) {
+ nb_sectors = DIV_ROUND_UP(total_size - start, BDRV_SECTOR_SIZE);
+ }
+
+ 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,
+ * possibly including a partial sector at EOF. */
+ *pnum = MIN(nb_sectors, DIV_ROUND_UP(hole - start, BDRV_SECTOR_SIZE));
+ 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);
+ ret = BDRV_BLOCK_ZERO;
+ }
+
+ *file = bs;
+
+ return ret | BDRV_BLOCK_OFFSET_VALID | start;
}
+
static QemuOptsList qemu_gluster_create_opts = {
.name = "qemu-gluster-create-opts",
.head = QTAILQ_HEAD_INITIALIZER(qemu_gluster_create_opts.head),
.type = QEMU_OPT_STRING,
.help = "Preallocation mode (allowed values: off, full)"
},
+ {
+ .name = GLUSTER_OPT_DEBUG,
+ .type = QEMU_OPT_NUMBER,
+ .help = "Gluster log level, valid range is 0-9",
+ },
{ /* end of list */ }
}
};
.bdrv_co_discard = qemu_gluster_co_discard,
#endif
#ifdef CONFIG_GLUSTERFS_ZEROFILL
- .bdrv_co_write_zeroes = qemu_gluster_co_write_zeroes,
+ .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes,
#endif
+ .bdrv_co_get_block_status = qemu_gluster_co_get_block_status,
.create_opts = &qemu_gluster_create_opts,
};
.bdrv_co_discard = qemu_gluster_co_discard,
#endif
#ifdef CONFIG_GLUSTERFS_ZEROFILL
- .bdrv_co_write_zeroes = qemu_gluster_co_write_zeroes,
+ .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes,
#endif
+ .bdrv_co_get_block_status = qemu_gluster_co_get_block_status,
.create_opts = &qemu_gluster_create_opts,
};
.bdrv_co_discard = qemu_gluster_co_discard,
#endif
#ifdef CONFIG_GLUSTERFS_ZEROFILL
- .bdrv_co_write_zeroes = qemu_gluster_co_write_zeroes,
+ .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes,
#endif
+ .bdrv_co_get_block_status = qemu_gluster_co_get_block_status,
.create_opts = &qemu_gluster_create_opts,
};
.bdrv_co_discard = qemu_gluster_co_discard,
#endif
#ifdef CONFIG_GLUSTERFS_ZEROFILL
- .bdrv_co_write_zeroes = qemu_gluster_co_write_zeroes,
+ .bdrv_co_pwrite_zeroes = qemu_gluster_co_pwrite_zeroes,
#endif
+ .bdrv_co_get_block_status = qemu_gluster_co_get_block_status,
.create_opts = &qemu_gluster_create_opts,
};
projects / mirror_qemu.git / blobdiff