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-rw-r--r--block/gluster.c624
1 files changed, 624 insertions, 0 deletions
diff --git a/block/gluster.c b/block/gluster.c
new file mode 100644
index 0000000..3588d73
--- /dev/null
+++ b/block/gluster.c
@@ -0,0 +1,624 @@
+/*
+ * GlusterFS backend for QEMU
+ *
+ * Copyright (C) 2012 Bharata B Rao <bharata@linux.vnet.ibm.com>
+ *
+ * Pipe handling mechanism in AIO implementation is derived from
+ * block/rbd.c. Hence,
+ *
+ * Copyright (C) 2010-2011 Christian Brunner <chb@muc.de>,
+ * Josh Durgin <josh.durgin@dreamhost.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ * Contributions after 2012-01-13 are licensed under the terms of the
+ * GNU GPL, version 2 or (at your option) any later version.
+ */
+#include <glusterfs/api/glfs.h>
+#include "block_int.h"
+#include "qemu_socket.h"
+#include "uri.h"
+
+typedef struct GlusterAIOCB {
+ BlockDriverAIOCB common;
+ int64_t size;
+ int ret;
+ bool *finished;
+ QEMUBH *bh;
+} GlusterAIOCB;
+
+typedef struct BDRVGlusterState {
+ struct glfs *glfs;
+ int fds[2];
+ struct glfs_fd *fd;
+ int qemu_aio_count;
+ int event_reader_pos;
+ GlusterAIOCB *event_acb;
+} BDRVGlusterState;
+
+#define GLUSTER_FD_READ 0
+#define GLUSTER_FD_WRITE 1
+
+typedef struct GlusterConf {
+ char *server;
+ int port;
+ char *volname;
+ char *image;
+ char *transport;
+} GlusterConf;
+
+static void qemu_gluster_gconf_free(GlusterConf *gconf)
+{
+ g_free(gconf->server);
+ g_free(gconf->volname);
+ g_free(gconf->image);
+ g_free(gconf->transport);
+ g_free(gconf);
+}
+
+static int parse_volume_options(GlusterConf *gconf, char *path)
+{
+ char *p, *q;
+
+ if (!path) {
+ return -EINVAL;
+ }
+
+ /* volume */
+ p = q = path + strspn(path, "/");
+ p += strcspn(p, "/");
+ if (*p == '\0') {
+ return -EINVAL;
+ }
+ gconf->volname = g_strndup(q, p - q);
+
+ /* image */
+ p += strspn(p, "/");
+ if (*p == '\0') {
+ return -EINVAL;
+ }
+ gconf->image = g_strdup(p);
+ return 0;
+}
+
+/*
+ * file=gluster[+transport]://[server[:port]]/volname/image[?socket=...]
+ *
+ * 'gluster' is the protocol.
+ *
+ * 'transport' specifies the transport type used to connect to gluster
+ * management daemon (glusterd). Valid transport types are
+ * tcp, unix and rdma. If a transport type isn't specified, then tcp
+ * type is assumed.
+ *
+ * 'server' specifies the server where the volume file specification for
+ * the given volume resides. This can be either hostname, ipv4 address
+ * or ipv6 address. ipv6 address needs to be within square brackets [ ].
+ * If transport type is 'unix', then 'server' field should not be specifed.
+ * The 'socket' field needs to be populated with the path to unix domain
+ * socket.
+ *
+ * 'port' is the port number on which glusterd is listening. This is optional
+ * and if not specified, QEMU will send 0 which will make gluster to use the
+ * default port. If the transport type is unix, then 'port' should not be
+ * specified.
+ *
+ * 'volname' is the name of the gluster volume which contains the VM image.
+ *
+ * 'image' is the path to the actual VM image that resides on gluster volume.
+ *
+ * Examples:
+ *
+ * file=gluster://1.2.3.4/testvol/a.img
+ * file=gluster+tcp://1.2.3.4/testvol/a.img
+ * file=gluster+tcp://1.2.3.4:24007/testvol/dir/a.img
+ * file=gluster+tcp://[1:2:3:4:5:6:7:8]/testvol/dir/a.img
+ * file=gluster+tcp://[1:2:3:4:5:6:7:8]:24007/testvol/dir/a.img
+ * file=gluster+tcp://server.domain.com:24007/testvol/dir/a.img
+ * file=gluster+unix:///testvol/dir/a.img?socket=/tmp/glusterd.socket
+ * file=gluster+rdma://1.2.3.4:24007/testvol/a.img
+ */
+static int qemu_gluster_parseuri(GlusterConf *gconf, const char *filename)
+{
+ URI *uri;
+ QueryParams *qp = NULL;
+ bool is_unix = false;
+ int ret = 0;
+
+ uri = uri_parse(filename);
+ if (!uri) {
+ return -EINVAL;
+ }
+
+ /* transport */
+ if (!strcmp(uri->scheme, "gluster")) {
+ gconf->transport = g_strdup("tcp");
+ } else if (!strcmp(uri->scheme, "gluster+tcp")) {
+ gconf->transport = g_strdup("tcp");
+ } else if (!strcmp(uri->scheme, "gluster+unix")) {
+ gconf->transport = g_strdup("unix");
+ is_unix = true;
+ } else if (!strcmp(uri->scheme, "gluster+rdma")) {
+ gconf->transport = g_strdup("rdma");
+ } else {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = parse_volume_options(gconf, uri->path);
+ if (ret < 0) {
+ goto out;
+ }
+
+ qp = query_params_parse(uri->query);
+ if (qp->n > 1 || (is_unix && !qp->n) || (!is_unix && qp->n)) {
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (is_unix) {
+ if (uri->server || uri->port) {
+ ret = -EINVAL;
+ goto out;
+ }
+ if (strcmp(qp->p[0].name, "socket")) {
+ ret = -EINVAL;
+ goto out;
+ }
+ gconf->server = g_strdup(qp->p[0].value);
+ } else {
+ gconf->server = g_strdup(uri->server);
+ gconf->port = uri->port;
+ }
+
+out:
+ if (qp) {
+ query_params_free(qp);
+ }
+ uri_free(uri);
+ return ret;
+}
+
+static struct glfs *qemu_gluster_init(GlusterConf *gconf, const char *filename)
+{
+ struct glfs *glfs = NULL;
+ int ret;
+ int old_errno;
+
+ ret = qemu_gluster_parseuri(gconf, filename);
+ if (ret < 0) {
+ error_report("Usage: file=gluster[+transport]://[server[:port]]/"
+ "volname/image[?socket=...]");
+ errno = -ret;
+ goto out;
+ }
+
+ glfs = glfs_new(gconf->volname);
+ if (!glfs) {
+ goto out;
+ }
+
+ ret = glfs_set_volfile_server(glfs, gconf->transport, gconf->server,
+ gconf->port);
+ if (ret < 0) {
+ 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);
+ if (ret < 0) {
+ goto out;
+ }
+
+ ret = glfs_init(glfs);
+ if (ret) {
+ error_report("Gluster connection failed for server=%s port=%d "
+ "volume=%s image=%s transport=%s\n", gconf->server, gconf->port,
+ gconf->volname, gconf->image, gconf->transport);
+ goto out;
+ }
+ return glfs;
+
+out:
+ if (glfs) {
+ old_errno = errno;
+ glfs_fini(glfs);
+ errno = old_errno;
+ }
+ return NULL;
+}
+
+static void qemu_gluster_complete_aio(GlusterAIOCB *acb, BDRVGlusterState *s)
+{
+ int ret;
+ bool *finished = acb->finished;
+ BlockDriverCompletionFunc *cb = acb->common.cb;
+ void *opaque = acb->common.opaque;
+
+ if (!acb->ret || acb->ret == acb->size) {
+ ret = 0; /* Success */
+ } else if (acb->ret < 0) {
+ ret = acb->ret; /* Read/Write failed */
+ } else {
+ ret = -EIO; /* Partial read/write - fail it */
+ }
+
+ s->qemu_aio_count--;
+ qemu_aio_release(acb);
+ cb(opaque, ret);
+ if (finished) {
+ *finished = true;
+ }
+}
+
+static void qemu_gluster_aio_event_reader(void *opaque)
+{
+ BDRVGlusterState *s = opaque;
+ ssize_t ret;
+
+ do {
+ char *p = (char *)&s->event_acb;
+
+ ret = read(s->fds[GLUSTER_FD_READ], p + s->event_reader_pos,
+ sizeof(s->event_acb) - s->event_reader_pos);
+ if (ret > 0) {
+ s->event_reader_pos += ret;
+ if (s->event_reader_pos == sizeof(s->event_acb)) {
+ s->event_reader_pos = 0;
+ qemu_gluster_complete_aio(s->event_acb, s);
+ }
+ }
+ } while (ret < 0 && errno == EINTR);
+}
+
+static int qemu_gluster_aio_flush_cb(void *opaque)
+{
+ BDRVGlusterState *s = opaque;
+
+ return (s->qemu_aio_count > 0);
+}
+
+static int qemu_gluster_open(BlockDriverState *bs, const char *filename,
+ int bdrv_flags)
+{
+ BDRVGlusterState *s = bs->opaque;
+ int open_flags = O_BINARY;
+ int ret = 0;
+ GlusterConf *gconf = g_malloc0(sizeof(GlusterConf));
+
+ s->glfs = qemu_gluster_init(gconf, filename);
+ if (!s->glfs) {
+ ret = -errno;
+ goto out;
+ }
+
+ if (bdrv_flags & BDRV_O_RDWR) {
+ open_flags |= O_RDWR;
+ } else {
+ open_flags |= O_RDONLY;
+ }
+
+ if ((bdrv_flags & BDRV_O_NOCACHE)) {
+ open_flags |= O_DIRECT;
+ }
+
+ s->fd = glfs_open(s->glfs, gconf->image, open_flags);
+ if (!s->fd) {
+ ret = -errno;
+ goto out;
+ }
+
+ ret = qemu_pipe(s->fds);
+ if (ret < 0) {
+ ret = -errno;
+ goto out;
+ }
+ fcntl(s->fds[GLUSTER_FD_READ], F_SETFL, O_NONBLOCK);
+ qemu_aio_set_fd_handler(s->fds[GLUSTER_FD_READ],
+ qemu_gluster_aio_event_reader, NULL, qemu_gluster_aio_flush_cb, s);
+
+out:
+ qemu_gluster_gconf_free(gconf);
+ if (!ret) {
+ return ret;
+ }
+ if (s->fd) {
+ glfs_close(s->fd);
+ }
+ if (s->glfs) {
+ glfs_fini(s->glfs);
+ }
+ return ret;
+}
+
+static int qemu_gluster_create(const char *filename,
+ QEMUOptionParameter *options)
+{
+ struct glfs *glfs;
+ struct glfs_fd *fd;
+ int ret = 0;
+ int64_t total_size = 0;
+ GlusterConf *gconf = g_malloc0(sizeof(GlusterConf));
+
+ glfs = qemu_gluster_init(gconf, filename);
+ if (!glfs) {
+ ret = -errno;
+ goto out;
+ }
+
+ while (options && options->name) {
+ if (!strcmp(options->name, BLOCK_OPT_SIZE)) {
+ total_size = options->value.n / BDRV_SECTOR_SIZE;
+ }
+ options++;
+ }
+
+ fd = glfs_creat(glfs, gconf->image,
+ O_WRONLY | O_CREAT | O_TRUNC | O_BINARY, S_IRUSR | S_IWUSR);
+ if (!fd) {
+ ret = -errno;
+ } else {
+ if (glfs_ftruncate(fd, total_size * BDRV_SECTOR_SIZE) != 0) {
+ ret = -errno;
+ }
+ if (glfs_close(fd) != 0) {
+ ret = -errno;
+ }
+ }
+out:
+ qemu_gluster_gconf_free(gconf);
+ if (glfs) {
+ glfs_fini(glfs);
+ }
+ return ret;
+}
+
+static void qemu_gluster_aio_cancel(BlockDriverAIOCB *blockacb)
+{
+ GlusterAIOCB *acb = (GlusterAIOCB *)blockacb;
+ bool finished = false;
+
+ acb->finished = &finished;
+ while (!finished) {
+ qemu_aio_wait();
+ }
+}
+
+static AIOPool gluster_aio_pool = {
+ .aiocb_size = sizeof(GlusterAIOCB),
+ .cancel = qemu_gluster_aio_cancel,
+};
+
+static void gluster_finish_aiocb(struct glfs_fd *fd, ssize_t ret, void *arg)
+{
+ GlusterAIOCB *acb = (GlusterAIOCB *)arg;
+ BlockDriverState *bs = acb->common.bs;
+ BDRVGlusterState *s = bs->opaque;
+ int retval;
+
+ acb->ret = ret;
+ retval = qemu_write_full(s->fds[GLUSTER_FD_WRITE], &acb, sizeof(acb));
+ if (retval != sizeof(acb)) {
+ /*
+ * Gluster AIO callback thread failed to notify the waiting
+ * QEMU thread about IO completion.
+ *
+ * Complete this IO request and make the disk inaccessible for
+ * subsequent reads and writes.
+ */
+ error_report("Gluster failed to notify QEMU about IO completion");
+
+ qemu_mutex_lock_iothread(); /* We are in gluster thread context */
+ acb->common.cb(acb->common.opaque, -EIO);
+ qemu_aio_release(acb);
+ s->qemu_aio_count--;
+ close(s->fds[GLUSTER_FD_READ]);
+ close(s->fds[GLUSTER_FD_WRITE]);
+ qemu_aio_set_fd_handler(s->fds[GLUSTER_FD_READ], NULL, NULL, NULL,
+ NULL);
+ bs->drv = NULL; /* Make the disk inaccessible */
+ qemu_mutex_unlock_iothread();
+ }
+}
+
+static BlockDriverAIOCB *qemu_gluster_aio_rw(BlockDriverState *bs,
+ int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
+ BlockDriverCompletionFunc *cb, void *opaque, int write)
+{
+ int ret;
+ GlusterAIOCB *acb;
+ BDRVGlusterState *s = bs->opaque;
+ size_t size;
+ off_t offset;
+
+ offset = sector_num * BDRV_SECTOR_SIZE;
+ size = nb_sectors * BDRV_SECTOR_SIZE;
+ s->qemu_aio_count++;
+
+ acb = qemu_aio_get(&gluster_aio_pool, bs, cb, opaque);
+ acb->size = size;
+ acb->ret = 0;
+ acb->finished = NULL;
+
+ if (write) {
+ ret = glfs_pwritev_async(s->fd, qiov->iov, qiov->niov, offset, 0,
+ &gluster_finish_aiocb, acb);
+ } else {
+ ret = glfs_preadv_async(s->fd, qiov->iov, qiov->niov, offset, 0,
+ &gluster_finish_aiocb, acb);
+ }
+
+ if (ret < 0) {
+ goto out;
+ }
+ return &acb->common;
+
+out:
+ s->qemu_aio_count--;
+ qemu_aio_release(acb);
+ return NULL;
+}
+
+static BlockDriverAIOCB *qemu_gluster_aio_readv(BlockDriverState *bs,
+ int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
+ BlockDriverCompletionFunc *cb, void *opaque)
+{
+ return qemu_gluster_aio_rw(bs, sector_num, qiov, nb_sectors, cb, opaque, 0);
+}
+
+static BlockDriverAIOCB *qemu_gluster_aio_writev(BlockDriverState *bs,
+ int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
+ BlockDriverCompletionFunc *cb, void *opaque)
+{
+ return qemu_gluster_aio_rw(bs, sector_num, qiov, nb_sectors, cb, opaque, 1);
+}
+
+static BlockDriverAIOCB *qemu_gluster_aio_flush(BlockDriverState *bs,
+ BlockDriverCompletionFunc *cb, void *opaque)
+{
+ int ret;
+ GlusterAIOCB *acb;
+ BDRVGlusterState *s = bs->opaque;
+
+ acb = qemu_aio_get(&gluster_aio_pool, bs, cb, opaque);
+ acb->size = 0;
+ acb->ret = 0;
+ acb->finished = NULL;
+ s->qemu_aio_count++;
+
+ ret = glfs_fsync_async(s->fd, &gluster_finish_aiocb, acb);
+ if (ret < 0) {
+ goto out;
+ }
+ return &acb->common;
+
+out:
+ s->qemu_aio_count--;
+ qemu_aio_release(acb);
+ return NULL;
+}
+
+static int64_t qemu_gluster_getlength(BlockDriverState *bs)
+{
+ BDRVGlusterState *s = bs->opaque;
+ int64_t ret;
+
+ ret = glfs_lseek(s->fd, 0, SEEK_END);
+ if (ret < 0) {
+ return -errno;
+ } else {
+ return ret;
+ }
+}
+
+static int64_t qemu_gluster_allocated_file_size(BlockDriverState *bs)
+{
+ BDRVGlusterState *s = bs->opaque;
+ struct stat st;
+ int ret;
+
+ ret = glfs_fstat(s->fd, &st);
+ if (ret < 0) {
+ return -errno;
+ } else {
+ return st.st_blocks * 512;
+ }
+}
+
+static void qemu_gluster_close(BlockDriverState *bs)
+{
+ BDRVGlusterState *s = bs->opaque;
+
+ close(s->fds[GLUSTER_FD_READ]);
+ close(s->fds[GLUSTER_FD_WRITE]);
+ qemu_aio_set_fd_handler(s->fds[GLUSTER_FD_READ], NULL, NULL, NULL, NULL);
+
+ if (s->fd) {
+ glfs_close(s->fd);
+ s->fd = NULL;
+ }
+ glfs_fini(s->glfs);
+}
+
+static QEMUOptionParameter qemu_gluster_create_options[] = {
+ {
+ .name = BLOCK_OPT_SIZE,
+ .type = OPT_SIZE,
+ .help = "Virtual disk size"
+ },
+ { NULL }
+};
+
+static BlockDriver bdrv_gluster = {
+ .format_name = "gluster",
+ .protocol_name = "gluster",
+ .instance_size = sizeof(BDRVGlusterState),
+ .bdrv_file_open = qemu_gluster_open,
+ .bdrv_close = qemu_gluster_close,
+ .bdrv_create = qemu_gluster_create,
+ .bdrv_getlength = qemu_gluster_getlength,
+ .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size,
+ .bdrv_aio_readv = qemu_gluster_aio_readv,
+ .bdrv_aio_writev = qemu_gluster_aio_writev,
+ .bdrv_aio_flush = qemu_gluster_aio_flush,
+ .create_options = qemu_gluster_create_options,
+};
+
+static BlockDriver bdrv_gluster_tcp = {
+ .format_name = "gluster",
+ .protocol_name = "gluster+tcp",
+ .instance_size = sizeof(BDRVGlusterState),
+ .bdrv_file_open = qemu_gluster_open,
+ .bdrv_close = qemu_gluster_close,
+ .bdrv_create = qemu_gluster_create,
+ .bdrv_getlength = qemu_gluster_getlength,
+ .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size,
+ .bdrv_aio_readv = qemu_gluster_aio_readv,
+ .bdrv_aio_writev = qemu_gluster_aio_writev,
+ .bdrv_aio_flush = qemu_gluster_aio_flush,
+ .create_options = qemu_gluster_create_options,
+};
+
+static BlockDriver bdrv_gluster_unix = {
+ .format_name = "gluster",
+ .protocol_name = "gluster+unix",
+ .instance_size = sizeof(BDRVGlusterState),
+ .bdrv_file_open = qemu_gluster_open,
+ .bdrv_close = qemu_gluster_close,
+ .bdrv_create = qemu_gluster_create,
+ .bdrv_getlength = qemu_gluster_getlength,
+ .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size,
+ .bdrv_aio_readv = qemu_gluster_aio_readv,
+ .bdrv_aio_writev = qemu_gluster_aio_writev,
+ .bdrv_aio_flush = qemu_gluster_aio_flush,
+ .create_options = qemu_gluster_create_options,
+};
+
+static BlockDriver bdrv_gluster_rdma = {
+ .format_name = "gluster",
+ .protocol_name = "gluster+rdma",
+ .instance_size = sizeof(BDRVGlusterState),
+ .bdrv_file_open = qemu_gluster_open,
+ .bdrv_close = qemu_gluster_close,
+ .bdrv_create = qemu_gluster_create,
+ .bdrv_getlength = qemu_gluster_getlength,
+ .bdrv_get_allocated_file_size = qemu_gluster_allocated_file_size,
+ .bdrv_aio_readv = qemu_gluster_aio_readv,
+ .bdrv_aio_writev = qemu_gluster_aio_writev,
+ .bdrv_aio_flush = qemu_gluster_aio_flush,
+ .create_options = qemu_gluster_create_options,
+};
+
+static void bdrv_gluster_init(void)
+{
+ bdrv_register(&bdrv_gluster_rdma);
+ bdrv_register(&bdrv_gluster_unix);
+ bdrv_register(&bdrv_gluster_tcp);
+ bdrv_register(&bdrv_gluster);
+}
+
+block_init(bdrv_gluster_init);
generated by cgit v1.1 at 2024-12-26 18:23:30 +0000