diff options
| -rw-r--r-- | drivers/block/rbd.c | 127 |
1 files changed, 99 insertions, 28 deletions
diff --git a/drivers/block/rbd.c b/drivers/block/rbd.c index 366a3a1f2aac..3b284d53a566 100644 --- a/drivers/block/rbd.c +++ b/drivers/block/rbd.c @@ -170,6 +170,7 @@ struct rbd_device { int major; /* blkdev assigned major */ struct gendisk *disk; /* blkdev's gendisk and rq */ + u32 image_format; /* Either 1 or 2 */ struct rbd_options rbd_opts; struct rbd_client *rbd_client; @@ -507,6 +508,11 @@ static void rbd_coll_release(struct kref *kref) kfree(coll); } +static bool rbd_image_format_valid(u32 image_format) +{ + return image_format == 1 || image_format == 2; +} + static bool rbd_dev_ondisk_valid(struct rbd_image_header_ondisk *ondisk) { size_t size; @@ -2584,6 +2590,96 @@ out: return ret; } +static int rbd_dev_v1_probe(struct rbd_device *rbd_dev) +{ + int ret; + size_t size; + + /* Version 1 images have no id; empty string is used */ + + rbd_dev->image_id = kstrdup("", GFP_KERNEL); + if (!rbd_dev->image_id) + return -ENOMEM; + rbd_dev->image_id_len = 0; + + /* Record the header object name for this rbd image. */ + + size = rbd_dev->image_name_len + sizeof (RBD_SUFFIX); + rbd_dev->header_name = kmalloc(size, GFP_KERNEL); + if (!rbd_dev->header_name) { + ret = -ENOMEM; + goto out_err; + } + sprintf(rbd_dev->header_name, "%s%s", rbd_dev->image_name, RBD_SUFFIX); + + /* Populate rbd image metadata */ + + ret = rbd_read_header(rbd_dev, &rbd_dev->header); + if (ret < 0) + goto out_err; + rbd_dev->image_format = 1; + + dout("discovered version 1 image, header name is %s\n", + rbd_dev->header_name); + + return 0; + +out_err: + kfree(rbd_dev->header_name); + rbd_dev->header_name = NULL; + kfree(rbd_dev->image_id); + rbd_dev->image_id = NULL; + + return ret; +} + +static int rbd_dev_v2_probe(struct rbd_device *rbd_dev) +{ + size_t size; + + /* + * Image id was filled in by the caller. Record the header + * object name for this rbd image. + */ + size = sizeof (RBD_HEADER_PREFIX) + rbd_dev->image_id_len; + rbd_dev->header_name = kmalloc(size, GFP_KERNEL); + if (!rbd_dev->header_name) + return -ENOMEM; + sprintf(rbd_dev->header_name, "%s%s", + RBD_HEADER_PREFIX, rbd_dev->image_id); + rbd_dev->image_format = 2; + + dout("discovered version 2 image, header name is %s\n", + rbd_dev->header_name); + + return -ENOTSUPP; +} + +/* + * Probe for the existence of the header object for the given rbd + * device. For format 2 images this includes determining the image + * id. + */ +static int rbd_dev_probe(struct rbd_device *rbd_dev) +{ + int ret; + + /* + * Get the id from the image id object. If it's not a + * format 2 image, we'll get ENOENT back, and we'll assume + * it's a format 1 image. + */ + ret = rbd_dev_image_id(rbd_dev); + if (ret) + ret = rbd_dev_v1_probe(rbd_dev); + else + ret = rbd_dev_v2_probe(rbd_dev); + if (ret) + dout("probe failed, returning %d\n", ret); + + return ret; +} + static ssize_t rbd_add(struct bus_type *bus, const char *buf, size_t count) @@ -2631,35 +2727,10 @@ static ssize_t rbd_add(struct bus_type *bus, goto err_out_client; rbd_dev->pool_id = rc; - rc = rbd_dev_image_id(rbd_dev); - if (!rc) { - rc = -ENOTSUPP; /* Not actually supporting format 2 yet */ - goto err_out_client; - } - - /* Version 1 images have no id; empty string is used */ - - rbd_dev->image_id = kstrdup("", GFP_KERNEL); - if (!rbd_dev->image_id) { - rc = -ENOMEM; - goto err_out_client; - } - rbd_dev->image_id_len = 0; - - /* Create the name of the header object */ - - rbd_dev->header_name = kmalloc(rbd_dev->image_name_len - + sizeof (RBD_SUFFIX), - GFP_KERNEL); - if (!rbd_dev->header_name) - goto err_out_client; - sprintf(rbd_dev->header_name, "%s%s", rbd_dev->image_name, RBD_SUFFIX); - - /* Get information about the image being mapped */ - - rc = rbd_read_header(rbd_dev, &rbd_dev->header); - if (rc) + rc = rbd_dev_probe(rbd_dev); + if (rc < 0) goto err_out_client; + rbd_assert(rbd_image_format_valid(rbd_dev->image_format)); /* no need to lock here, as rbd_dev is not registered yet */ rc = rbd_dev_snaps_update(rbd_dev); |