* block device image metadata (in-memory version)
*/
struct rbd_image_header {
- /* These four fields never change for a given rbd image */
+ /* These six fields never change for a given rbd image */
char *object_prefix;
- u64 features;
__u8 obj_order;
__u8 crypt_type;
__u8 comp_type;
+ u64 stripe_unit;
+ u64 stripe_count;
+ u64 features; /* Might be changeable someday? */
/* The remaining fields need to be updated occasionally */
u64 image_size;
struct ceph_snap_context *snapc;
- char *snap_names;
- u64 *snap_sizes;
-
- u64 stripe_unit;
- u64 stripe_count;
+ char *snap_names; /* format 1 only */
+ u64 *snap_sizes; /* format 1 only */
};
/*
size_t count);
static ssize_t rbd_remove(struct bus_type *bus, const char *buf,
size_t count);
-static int rbd_dev_image_probe(struct rbd_device *rbd_dev);
+static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool read_only);
static struct bus_attribute rbd_bus_attrs[] = {
__ATTR(add, S_IWUSR, NULL, rbd_add),
}
/*
- * Create a new header structure, translate header format from the on-disk
- * header.
+ * Fill an rbd image header with information from the given format 1
+ * on-disk header.
*/
-static int rbd_header_from_disk(struct rbd_image_header *header,
+static int rbd_header_from_disk(struct rbd_device *rbd_dev,
struct rbd_image_header_ondisk *ondisk)
{
+ struct rbd_image_header *header = &rbd_dev->header;
+ bool first_time = header->object_prefix == NULL;
+ struct ceph_snap_context *snapc;
+ char *object_prefix = NULL;
+ char *snap_names = NULL;
+ u64 *snap_sizes = NULL;
u32 snap_count;
- size_t len;
size_t size;
+ int ret = -ENOMEM;
u32 i;
- memset(header, 0, sizeof (*header));
+ /* Allocate this now to avoid having to handle failure below */
- snap_count = le32_to_cpu(ondisk->snap_count);
+ if (first_time) {
+ size_t len;
- len = strnlen(ondisk->object_prefix, sizeof (ondisk->object_prefix));
- header->object_prefix = kmalloc(len + 1, GFP_KERNEL);
- if (!header->object_prefix)
- return -ENOMEM;
- memcpy(header->object_prefix, ondisk->object_prefix, len);
- header->object_prefix[len] = '\0';
+ len = strnlen(ondisk->object_prefix,
+ sizeof (ondisk->object_prefix));
+ object_prefix = kmalloc(len + 1, GFP_KERNEL);
+ if (!object_prefix)
+ return -ENOMEM;
+ memcpy(object_prefix, ondisk->object_prefix, len);
+ object_prefix[len] = '\0';
+ }
+ /* Allocate the snapshot context and fill it in */
+
+ snap_count = le32_to_cpu(ondisk->snap_count);
+ snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
+ if (!snapc)
+ goto out_err;
+ snapc->seq = le64_to_cpu(ondisk->snap_seq);
if (snap_count) {
+ struct rbd_image_snap_ondisk *snaps;
u64 snap_names_len = le64_to_cpu(ondisk->snap_names_len);
- /* Save a copy of the snapshot names */
+ /* We'll keep a copy of the snapshot names... */
- if (snap_names_len > (u64) SIZE_MAX)
- return -EIO;
- header->snap_names = kmalloc(snap_names_len, GFP_KERNEL);
- if (!header->snap_names)
+ if (snap_names_len > (u64)SIZE_MAX)
+ goto out_2big;
+ snap_names = kmalloc(snap_names_len, GFP_KERNEL);
+ if (!snap_names)
goto out_err;
+
+ /* ...as well as the array of their sizes. */
+
+ size = snap_count * sizeof (*header->snap_sizes);
+ snap_sizes = kmalloc(size, GFP_KERNEL);
+ if (!snap_sizes)
+ goto out_err;
+
/*
- * Note that rbd_dev_v1_header_read() guarantees
- * the ondisk buffer we're working with has
+ * Copy the names, and fill in each snapshot's id
+ * and size.
+ *
+ * Note that rbd_dev_v1_header_read() guarantees the
+ * ondisk buffer we're working with has
* snap_names_len bytes beyond the end of the
* snapshot id array, this memcpy() is safe.
*/
- memcpy(header->snap_names, &ondisk->snaps[snap_count],
- snap_names_len);
+ memcpy(snap_names, &ondisk->snaps[snap_count], snap_names_len);
+ snaps = ondisk->snaps;
+ for (i = 0; i < snap_count; i++) {
+ snapc->snaps[i] = le64_to_cpu(snaps[i].id);
+ snap_sizes[i] = le64_to_cpu(snaps[i].image_size);
+ }
+ }
- /* Record each snapshot's size */
+ /* We won't fail any more, fill in the header */
- size = snap_count * sizeof (*header->snap_sizes);
- header->snap_sizes = kmalloc(size, GFP_KERNEL);
- if (!header->snap_sizes)
- goto out_err;
- for (i = 0; i < snap_count; i++)
- header->snap_sizes[i] =
- le64_to_cpu(ondisk->snaps[i].image_size);
+ down_write(&rbd_dev->header_rwsem);
+ if (first_time) {
+ header->object_prefix = object_prefix;
+ header->obj_order = ondisk->options.order;
+ header->crypt_type = ondisk->options.crypt_type;
+ header->comp_type = ondisk->options.comp_type;
+ /* The rest aren't used for format 1 images */
+ header->stripe_unit = 0;
+ header->stripe_count = 0;
+ header->features = 0;
} else {
- header->snap_names = NULL;
- header->snap_sizes = NULL;
+ ceph_put_snap_context(header->snapc);
+ kfree(header->snap_names);
+ kfree(header->snap_sizes);
}
- header->features = 0; /* No features support in v1 images */
- header->obj_order = ondisk->options.order;
- header->crypt_type = ondisk->options.crypt_type;
- header->comp_type = ondisk->options.comp_type;
-
- /* Allocate and fill in the snapshot context */
+ /* The remaining fields always get updated (when we refresh) */
header->image_size = le64_to_cpu(ondisk->image_size);
+ header->snapc = snapc;
+ header->snap_names = snap_names;
+ header->snap_sizes = snap_sizes;
- header->snapc = ceph_create_snap_context(snap_count, GFP_KERNEL);
- if (!header->snapc)
- goto out_err;
- header->snapc->seq = le64_to_cpu(ondisk->snap_seq);
- for (i = 0; i < snap_count; i++)
- header->snapc->snaps[i] = le64_to_cpu(ondisk->snaps[i].id);
+ /* Make sure mapping size is consistent with header info */
- return 0;
+ if (rbd_dev->spec->snap_id == CEPH_NOSNAP || first_time)
+ if (rbd_dev->mapping.size != header->image_size)
+ rbd_dev->mapping.size = header->image_size;
+
+ up_write(&rbd_dev->header_rwsem);
+ return 0;
+out_2big:
+ ret = -EIO;
out_err:
- kfree(header->snap_sizes);
- header->snap_sizes = NULL;
- kfree(header->snap_names);
- header->snap_names = NULL;
- kfree(header->object_prefix);
- header->object_prefix = NULL;
+ kfree(snap_sizes);
+ kfree(snap_names);
+ ceph_put_snap_context(snapc);
+ kfree(object_prefix);
- return -ENOMEM;
+ return ret;
}
static const char *_rbd_dev_v1_snap_name(struct rbd_device *rbd_dev, u32 which)
rbd_dev->mapping.size = size;
rbd_dev->mapping.features = features;
- /* If we are mapping a snapshot it must be marked read-only */
-
- if (snap_id != CEPH_NOSNAP)
- rbd_dev->mapping.read_only = true;
-
return 0;
}
{
rbd_dev->mapping.size = 0;
rbd_dev->mapping.features = 0;
- rbd_dev->mapping.read_only = true;
}
static const char *rbd_segment_name(struct rbd_device *rbd_dev, u64 offset)
}
/*
- * Read the complete header for the given rbd device.
- *
- * Returns a pointer to a dynamically-allocated buffer containing
- * the complete and validated header. Caller can pass the address
- * of a variable that will be filled in with the version of the
- * header object at the time it was read.
- *
- * Returns a pointer-coded errno if a failure occurs.
+ * Read the complete header for the given rbd device. On successful
+ * return, the rbd_dev->header field will contain up-to-date
+ * information about the image.
*/
-static struct rbd_image_header_ondisk *
-rbd_dev_v1_header_read(struct rbd_device *rbd_dev)
+static int rbd_dev_v1_header_read(struct rbd_device *rbd_dev)
{
struct rbd_image_header_ondisk *ondisk = NULL;
u32 snap_count = 0;
size += names_size;
ondisk = kmalloc(size, GFP_KERNEL);
if (!ondisk)
- return ERR_PTR(-ENOMEM);
+ return -ENOMEM;
ret = rbd_obj_read_sync(rbd_dev, rbd_dev->header_name,
0, size, ondisk);
if (ret < 0)
- goto out_err;
+ goto out;
if ((size_t)ret < size) {
ret = -ENXIO;
rbd_warn(rbd_dev, "short header read (want %zd got %d)",
size, ret);
- goto out_err;
+ goto out;
}
if (!rbd_dev_ondisk_valid(ondisk)) {
ret = -ENXIO;
rbd_warn(rbd_dev, "invalid header");
- goto out_err;
+ goto out;
}
names_size = le64_to_cpu(ondisk->snap_names_len);
snap_count = le32_to_cpu(ondisk->snap_count);
} while (snap_count != want_count);
- return ondisk;
-
-out_err:
- kfree(ondisk);
-
- return ERR_PTR(ret);
-}
-
-/*
- * reload the ondisk the header
- */
-static int rbd_read_header(struct rbd_device *rbd_dev,
- struct rbd_image_header *header)
-{
- struct rbd_image_header_ondisk *ondisk;
- int ret;
-
- ondisk = rbd_dev_v1_header_read(rbd_dev);
- if (IS_ERR(ondisk))
- return PTR_ERR(ondisk);
- ret = rbd_header_from_disk(header, ondisk);
+ ret = rbd_header_from_disk(rbd_dev, ondisk);
+out:
kfree(ondisk);
return ret;
*/
static int rbd_dev_v1_refresh(struct rbd_device *rbd_dev)
{
- int ret;
- struct rbd_image_header h;
-
- ret = rbd_read_header(rbd_dev, &h);
- if (ret < 0)
- return ret;
-
- down_write(&rbd_dev->header_rwsem);
-
- /* Update image size, and check for resize of mapped image */
- rbd_dev->header.image_size = h.image_size;
- if (rbd_dev->spec->snap_id == CEPH_NOSNAP)
- if (rbd_dev->mapping.size != rbd_dev->header.image_size)
- rbd_dev->mapping.size = rbd_dev->header.image_size;
-
- /* rbd_dev->header.object_prefix shouldn't change */
- kfree(rbd_dev->header.snap_sizes);
- kfree(rbd_dev->header.snap_names);
- /* osd requests may still refer to snapc */
- ceph_put_snap_context(rbd_dev->header.snapc);
-
- rbd_dev->header.image_size = h.image_size;
- rbd_dev->header.snapc = h.snapc;
- rbd_dev->header.snap_names = h.snap_names;
- rbd_dev->header.snap_sizes = h.snap_sizes;
- /* Free the extra copy of the object prefix */
- if (strcmp(rbd_dev->header.object_prefix, h.object_prefix))
- rbd_warn(rbd_dev, "object prefix changed (ignoring)");
- kfree(h.object_prefix);
-
- up_write(&rbd_dev->header_rwsem);
-
- return ret;
+ return rbd_dev_v1_header_read(rbd_dev);
}
/*
static int rbd_dev_v1_probe(struct rbd_device *rbd_dev)
{
- int ret;
-
- /* Populate rbd image metadata */
-
- ret = rbd_read_header(rbd_dev, &rbd_dev->header);
- if (ret < 0)
- goto out_err;
-
- /* Version 1 images have no parent (no layering) */
-
- rbd_dev->parent_spec = NULL;
- rbd_dev->parent_overlap = 0;
-
- 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->spec->image_id);
- rbd_dev->spec->image_id = NULL;
-
- return ret;
+ return rbd_dev_v1_header_read(rbd_dev);
}
static int rbd_dev_v2_probe(struct rbd_device *rbd_dev)
if (ret)
goto out_err;
- dout("discovered version 2 image, header name is %s\n",
- rbd_dev->header_name);
-
return 0;
out_err:
rbd_dev->parent_overlap = 0;
if (!parent)
goto out_err;
- ret = rbd_dev_image_probe(parent);
+ ret = rbd_dev_image_probe(parent, true);
if (ret < 0)
goto out_err;
rbd_dev->parent = parent;
{
int ret;
- ret = rbd_dev_mapping_set(rbd_dev);
- if (ret)
- return ret;
-
/* generate unique id: find highest unique id, add one */
rbd_dev_id_get(rbd_dev);
if (ret)
goto err_out_blkdev;
- ret = rbd_bus_add_dev(rbd_dev);
+ ret = rbd_dev_mapping_set(rbd_dev);
if (ret)
goto err_out_disk;
+ set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
+
+ ret = rbd_bus_add_dev(rbd_dev);
+ if (ret)
+ goto err_out_mapping;
/* Everything's ready. Announce the disk to the world. */
- set_capacity(rbd_dev->disk, rbd_dev->mapping.size / SECTOR_SIZE);
set_bit(RBD_DEV_FLAG_EXISTS, &rbd_dev->flags);
add_disk(rbd_dev->disk);
return ret;
+err_out_mapping:
+ rbd_dev_mapping_clear(rbd_dev);
err_out_disk:
rbd_free_disk(rbd_dev);
err_out_blkdev:
* device. For format 2 images this includes determining the image
* id.
*/
-static int rbd_dev_image_probe(struct rbd_device *rbd_dev)
+static int rbd_dev_image_probe(struct rbd_device *rbd_dev, bool read_only)
{
int ret;
int tmp;
if (ret)
goto err_out_probe;
+ /* If we are mapping a snapshot it must be marked read-only */
+
+ if (rbd_dev->spec->snap_id != CEPH_NOSNAP)
+ read_only = true;
+ rbd_dev->mapping.read_only = read_only;
+
ret = rbd_dev_probe_parent(rbd_dev);
- if (!ret)
- return 0;
+ if (ret)
+ goto err_out_probe;
+ dout("discovered format %u image, header name is %s\n",
+ rbd_dev->image_format, rbd_dev->header_name);
+
+ return 0;
err_out_probe:
rbd_dev_unprobe(rbd_dev);
err_out_watch:
struct rbd_spec *spec = NULL;
struct rbd_client *rbdc;
struct ceph_osd_client *osdc;
+ bool read_only;
int rc = -ENOMEM;
if (!try_module_get(THIS_MODULE))
rc = rbd_add_parse_args(buf, &ceph_opts, &rbd_opts, &spec);
if (rc < 0)
goto err_out_module;
+ read_only = rbd_opts->read_only;
+ kfree(rbd_opts);
+ rbd_opts = NULL; /* done with this */
rbdc = rbd_get_client(ceph_opts);
if (IS_ERR(rbdc)) {
rbdc = NULL; /* rbd_dev now owns this */
spec = NULL; /* rbd_dev now owns this */
- rbd_dev->mapping.read_only = rbd_opts->read_only;
- kfree(rbd_opts);
- rbd_opts = NULL; /* done with this */
-
- rc = rbd_dev_image_probe(rbd_dev);
+ rc = rbd_dev_image_probe(rbd_dev, read_only);
if (rc < 0)
goto err_out_rbd_dev;
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