This adds the rbd under fs/ceph. The rados block device is
based on the drivers/block/osdblk.c. It allows mapping of
rados (ther ceph block layer) objects over a block device.
Each device has a metadata object, and data is being striped
across different objects.
Signed-off-by: Yehuda Sadeh <yehuda@xxxxxxxxxxxxxxx>
---
fs/ceph/Makefile | 3 +-
fs/ceph/rbd.c | 1224 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
fs/ceph/rbd.h | 8 +
fs/ceph/super.c | 8 +
4 files changed, 1242 insertions(+), 1 deletions(-)
diff --git a/fs/ceph/Makefile b/fs/ceph/Makefile
index 6a660e6..f06ff40 100644
--- a/fs/ceph/Makefile
+++ b/fs/ceph/Makefile
@@ -16,7 +16,8 @@ ceph-objs := super.o inode.o dir.o file.o addr.o ioctl.o \
auth.o auth_none.o \
crypto.o armor.o \
auth_x.o \
- ceph_fs.o ceph_strings.o ceph_hash.o ceph_frag.o
+ ceph_fs.o ceph_strings.o ceph_hash.o ceph_frag.o \
+ rbd.o
else
#Otherwise we were called directly from the command
diff --git a/fs/ceph/rbd.c b/fs/ceph/rbd.c
new file mode 100644
index 0000000..3f7a7bd
--- /dev/null
+++ b/fs/ceph/rbd.c
@@ -0,0 +1,1224 @@
+/*
+ rbd.c -- Export ceph rados objects as a Linux block device
+
+
+ based on drivers/block/osdblk.c:
+
+ Copyright 2009 Red Hat, Inc.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; see the file COPYING. If not, write to
+ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
+
+
+
+ Instructions for use
+ --------------------
+
+ 1) Map a Linux block device to an existing rbd image.
+
+ Usage: <mon ip addr> <options> <pool id> <rbd image name>
+
+ $ echo "192.168.0.1 name=admin 0 foo" > /sys/class/rbd/add
+
+
+ 2) List all active blkdev<->object mappings.
+
+ In this example, we have performed step #1 twice, creating two blkdevs,
+ mapped to two separate rados objects in rados pool 0.
+
+ $ cat /sys/class/rbd/list
+ 0 254 0 foo
+ 1 253 0 bar
+
+ The columns, in order, are:
+ - blkdev unique id
+ - blkdev assigned major
+ - rados pool id
+ - rados block device name
+
+
+ 3) Remove an active blkdev<->rbd image mapping.
+
+ In this example, we remove the mapping with blkdev unique id 1.
+
+ $ echo 1 > /sys/class/rbd/remove
+
+
+ NOTE: The actual creation and deletion of rados objects is outside the scope
+ of this driver.
+
+ */
+
+#include "super.h"
+#include "osd_client.h"
+
+#include <linux/kernel.h>
+#include <linux/device.h>
+#include <linux/module.h>
+#include <linux/fs.h>
+#include <linux/blkdev.h>
+
+#define DRV_NAME "rbd"
+#define DRV_NAME_LONG "rbd (rados block device)"
+
+
+enum {
+ RBD_MINORS_PER_MAJOR = 256, /* max minors per blkdev */
+};
+
+static const char rbd_text[] = "<<< Rados Block Device Image >>>\n";
+static const char rbd_signature[] = "RBD";
+static const char rbd_version[] = "001.000";
+
+#define RBD_COMP_NONE 0
+#define RBD_CRYPT_NONE 0
+
+#define RBD_DEFAULT_OBJ_ORDER 22 /* 4MB */
+
+#define RBD_SUFFIX ".rbd"
+
+#define RBD_MAX_OBJ_NAME_SIZE 96
+#define RBD_MAX_SEG_NAME_SIZE 128
+
+#define RBD_STRIPE_UNIT (1 << 22)
+
+#define RBD_MAX_OPT_LEN 1024
+
+
+struct rbd_obj_header_ondisk {
+ char text[64];
+ char signature[4];
+ char version[8];
+ __le64 image_size;
+ __u8 obj_order;
+ __u8 crypt_type;
+ __u8 comp_type;
+ __le64 snap_seq;
+ __le16 snap_count;
+ __le64 snap_id[0];
+} __attribute__((packed));
+
+struct rbd_obj_header {
+ u64 image_size;
+ __u8 obj_order;
+ __u8 crypt_type;
+ __u8 comp_type;
+ u64 snap_seq;
+ u16 snap_count;
+ u64 snap_id[0];
+};
+
+struct rbd_request {
+ struct request *rq; /* blk layer request */
+ struct bio *bio; /* cloned bio */
+ struct page **pages; /* list of used pages */
+ u64 len;
+};
+
+struct rbd_client_node {
+ struct ceph_client *client;
+ const char *opt;
+ struct kref kref;
+ struct list_head node;
+};
+
+#define DEV_NAME_LEN 32
+
+struct rbd_device {
+ int id; /* blkdev unique id */
+
+ int major; /* blkdev assigned major */
+ struct gendisk *disk; /* blkdev's gendisk and rq */
+ struct request_queue *q;
+
+ struct ceph_client *client; /* associated OSD */
+
+ char name[DEV_NAME_LEN]; /* blkdev name, e.g. rbd34 */
+
+ spinlock_t lock; /* queue lock */
+
+ struct rbd_obj_header *header;
+ char obj[RBD_MAX_OBJ_NAME_SIZE]; /* rbd image name */
+ int obj_len;
+ int poolid;
+
+ struct list_head node;
+ struct rbd_client_node *client_node;
+};
+
+static spinlock_t node_lock; /* protects client get/put */
+
+static struct class *class_rbd; /* /sys/class/rbd */
+static DEFINE_MUTEX(ctl_mutex); /* Serialize open/close/setup/teardown */
+static LIST_HEAD(rbddev_list);
+static LIST_HEAD(node_list);
+
+static const struct block_device_operations rbd_bd_ops = {
+ .owner = THIS_MODULE,
+};
+
+/*
+ * Initialize ceph client for a specific device.
+ */
+static int rbd_init_client(struct rbd_device *rbd_dev,
+ struct ceph_mount_args *args)
+{
+ dout("rbd_init_device\n");
+ rbd_dev->client = ceph_create_client(args, 0);
+ if (IS_ERR(rbd_dev->client))
+ return PTR_ERR(rbd_dev->client);
+
+ return ceph_open_session(rbd_dev->client);
+}
+
+/*
+ * Find a ceph client with specific addr and configuration.
+ */
+static struct rbd_client_node *__get_client_node(struct ceph_mount_args *args)
+{
+ struct rbd_client_node *client_node;
+
+ if (args->flags & CEPH_OPT_NOSHARE)
+ return NULL;
+
+ list_for_each_entry(client_node, &node_list, node)
+ if (ceph_compare_mount_args(args, client_node->client) == 0)
+ return client_node;
+ return NULL;
+}
+
+/*
+ * Get a ceph client with specific addr and configuration, if one does
+ * not exist create it.
+ */
+static int rbd_get_client(struct rbd_device *rbd_dev, const char *mon_addr,
+ char *opt)
+{
+ struct rbd_client_node *client_node;
+ struct ceph_mount_args *args;
+ int ret;
+
+ spin_lock(&node_lock);
+
+ args = parse_mount_args(0, opt, mon_addr, NULL);
+ if (IS_ERR(args))
+ return PTR_ERR(args);
+
+ client_node = __get_client_node(args);
+ if (client_node) {
+ kfree(args);
+
+ kref_get(&client_node->kref);
+ rbd_dev->client_node = client_node;
+ rbd_dev->client = client_node->client;
+ spin_unlock(&node_lock);
+ return 0;
+ }
+
+ spin_unlock(&node_lock);
+
+ ret = -ENOMEM;
+ client_node = kmalloc(sizeof(struct rbd_client_node), GFP_KERNEL);
+ if (!client_node)
+ goto out;
+
+ ret = rbd_init_client(rbd_dev, args);
+ if (ret < 0)
+ goto out_free;
+
+ client_node->client = rbd_dev->client;
+ client_node->opt = kstrdup(opt, GFP_KERNEL);
+ kref_init(&client_node->kref);
+ INIT_LIST_HEAD(&client_node->node);
+
+ rbd_dev->client_node = client_node;
+
+ spin_lock(&node_lock);
+ list_add_tail(&client_node->node, &node_list);
+ spin_unlock(&node_lock);
+
+ return 0;
+
+out_free:
+ kfree(client_node);
+out:
+ return ret;
+}
+
+/*
+ * Destroy ceph client
+ */
+static void rbd_release_client(struct kref *kref)
+{
+ struct rbd_client_node *node =
+ container_of(kref, struct rbd_client_node, kref);
+
+ dout("rbd_release_client\n");
+
+ spin_lock(&node_lock);
+ list_del(&node->node);
+ spin_unlock(&node_lock);
+
+ ceph_destroy_client(node->client);
+ kfree(node->opt);
+ kfree(node);
+}
+
+/*
+ * Drop reference to ceph client node. If it's not referenced anymore, release
+ * it.
+ */
+static void rbd_put_client(struct rbd_device *rbd_dev)
+{
+ if (!rbd_dev->client_node)
+ return;
+
+ kref_put(&rbd_dev->client_node->kref, rbd_release_client);
+ rbd_dev->client_node = NULL;
+}
+
+
+/*
+ * Create a new header structure, translate header format from the on-disk
+ * header.
+ */
+static int rbd_header_from_disk(struct rbd_obj_header **header,
+ struct rbd_obj_header_ondisk *ondisk,
+ gfp_t gfp_flags)
+{
+ int i;
+ u16 snap_count = le16_to_cpu(ondisk->snap_count);
+
+ *header = kmalloc(sizeof(struct rbd_obj_header) +
+ snap_count * sizeof(u32), gfp_flags);
+ if (!*header)
+ return -ENOMEM;
+
+ (*header)->image_size = le64_to_cpu(ondisk->image_size);
+ (*header)->obj_order = ondisk->obj_order;
+ (*header)->crypt_type = ondisk->crypt_type;
+ (*header)->comp_type = ondisk->comp_type;
+ (*header)->snap_seq = le64_to_cpu(ondisk->snap_seq);
+ (*header)->snap_count = snap_count;
+
+ for (i = 0; i < snap_count; i++)
+ (*header)->snap_id[i] = le64_to_cpu(ondisk->snap_id[i]);
+
+ return 0;
+}
+
+/*
+ * get the actual striped segment name, offset and length
+ */
+static u64 rbd_get_segment(struct rbd_obj_header *header,
+ const char *obj_name,
+ u64 ofs, u64 len,
+ char *seg_name, u64 *segofs)
+{
+ u64 seg = ofs >> header->obj_order;
+
+ if (seg_name)
+ snprintf(seg_name, RBD_MAX_SEG_NAME_SIZE,
+ "%s.%012llx", obj_name, seg);
+
+ ofs = ofs & ((1 << header->obj_order) - 1);
+ len = min_t(u64, len, (1 << header->obj_order) - ofs);
+
+ if (segofs)
+ *segofs = ofs;
+
+ return len;
+}
+
+static void bio_chain_put(struct bio *chain)
+{
+ struct bio *tmp;
+
+ while (chain) {
+ tmp = chain;
+ chain = chain->bi_next;
+
+ bio_put(tmp);
+ }
+}
+
+/*
+ * zeros a bio chain, starting at specific offset
+ */
+static void zero_bio_chain(struct bio *chain, int start_ofs)
+{
+ struct bio_vec *bv;
+ unsigned long flags;
+ void *buf;
+ int i;
+ int pos = 0;
+
+ while (chain) {
+ bio_for_each_segment(bv, chain, i) {
+ if (pos + bv->bv_len > start_ofs) {
+ int remainder = max(start_ofs - pos, 0);
+ buf = bvec_kmap_irq(bv, &flags);
+ memset(buf + remainder, 0,
+ bv->bv_len - remainder);
+ bvec_kunmap_irq(bv, &flags);
+ }
+ pos += bv->bv_len;
+ }
+
+ chain = chain->bi_next;
+ }
+}
+
+/*
+ * bio_chain_clone - clone a chain of bios up to a certain length.
+ * might return a bio_pair that will need to be released.
+ */
+static struct bio *bio_chain_clone(struct bio **old, struct bio **next,
+ struct bio_pair **bp,
+ int len, gfp_t gfpmask)
+{
+ struct bio *tmp, *old_chain = *old, *new_chain = NULL, *tail = NULL;
+ int total = 0;
+
+ if (*bp) {
+ bio_pair_release(*bp);
+ *bp = NULL;
+ }
+
+ while (old_chain && (total < len)) {
+ tmp = bio_kmalloc(gfpmask, old_chain->bi_max_vecs);
+ if (!tmp)
+ goto err_out;
+
+ if (total + old_chain->bi_size > len) {
+ struct bio_pair *bp;
+
+ /*
+ * this split can only happen with a single paged bio,
+ * split_bio will BUG_ON if this is not the case
+ */
+ dout("bio_chain_clone split! total=%d remaining=%d bi_size=%d\n",
+ (int)total, (int)len-total, (int)old_chain->bi_size);
+
+ /* split the bio. We'll release it either in the next
+ call, or it will have to be released outside */
+ bp = bio_split(old_chain, (len - total) / 512ULL);
+ if (!bp)
+ goto err_out;
+
+ __bio_clone(tmp, &bp->bio1);
+
+ *next = &bp->bio2;
+ } else {
+ __bio_clone(tmp, old_chain);
+ *next = old_chain->bi_next;
+ }
+
+ tmp->bi_bdev = NULL;
+ gfpmask &= ~__GFP_WAIT;
+ tmp->bi_next = NULL;
+
+ if (!new_chain) {
+ new_chain = tail = tmp;
+ } else {
+ tail->bi_next = tmp;
+ tail = tmp;
+ }
+ old_chain = old_chain->bi_next;
+
+ total += tmp->bi_size;
+ }
+
+ BUG_ON(total < len);
+
+ if (tail)
+ tail->bi_next = NULL;
+
+ *old = old_chain;
+
+ return new_chain;
+
+err_out:
+ dout("bio_chain_clone with err\n");
+ bio_chain_put(new_chain);
+ return NULL;
+}
+
+static void rbd_req_flush_object(struct request *rq,
+ const char *obj,
+ u64 offset, u64 len)
+{
+ /* not really flushing anything currently */
+ blk_end_request_all(rq, 0);
+}
+
+/*
+ * Send ceph osd request
+ */
+static int rbd_do_request(struct request *rq,
+ struct rbd_device *dev,
+ const char *obj, u64 ofs, u64 len,
+ struct bio *bio,
+ struct page **pages,
+ int num_pages,
+ int opcode, int flags,
+ int num_reply,
+ void (*rbd_cb)(struct ceph_osd_request *req,
+ struct ceph_msg *msg))
+{
+ struct ceph_osd_request *req;
+ struct ceph_file_layout *layout;
+ int ret;
+ u64 bno;
+ struct timespec mtime = CURRENT_TIME;
+ struct rbd_request *req_data;
+ struct ceph_osd_request_head *reqhead;
+
+ ret = -ENOMEM;
+ req_data = kzalloc(sizeof(*req_data), GFP_NOFS);
+ if (!req_data)
+ goto done;
+
+ dout("rbd_do_request len=%lld ofs=%lld\n", len, ofs);
+
+ req = ceph_osdc_alloc_request(&dev->client->osdc, flags,
+ NULL, 0,
+ false,
+ GFP_NOFS, pages, bio);
+ if (IS_ERR(req)) {
+ ret = PTR_ERR(req);
+ goto done_pages;
+ }
+
+ req->r_callback = rbd_cb;
+
+ req_data->rq = rq;
+ req_data->bio = bio;
+ req_data->pages = pages;
+ req_data->len = len;
+
+ req->r_priv = req_data;
+
+ reqhead = req->r_request->front.iov_base;
+ reqhead->snapid = cpu_to_le64(CEPH_NOSNAP);
+
+ strncpy(req->r_oid, obj, sizeof(req->r_oid));
+ req->r_oid_len = strlen(req->r_oid);
+
+ layout = &req->r_file_layout;
+ memset(layout, 0, sizeof(*layout));
+ layout->fl_stripe_unit = RBD_STRIPE_UNIT;
+ layout->fl_stripe_count = 1;
+ layout->fl_object_size = RBD_STRIPE_UNIT;
+ layout->fl_pg_preferred = -1;
+ layout->fl_pg_pool = dev->poolid;
+ ceph_calc_raw_layout(&dev->client->osdc, layout, ofs, len, &bno, req);
+
+ ceph_osdc_build_request(req, ofs, &len, opcode,
+ NULL, 0,
+ 0, 0,
+ &mtime,
+ req->r_oid, req->r_oid_len);
+
+ ret = ceph_osdc_start_request(&dev->client->osdc, req, false);
+ if (ret < 0)
+ goto done_err;
+
+ if (!rbd_cb) {
+ ret = ceph_osdc_wait_request(&dev->client->osdc, req);
+ ceph_osdc_put_request(req);
+ }
+ return ret;
+
+done_err:
+ bio_chain_put(req_data->bio);
+ ceph_osdc_put_request(req);
+done_pages:
+ kfree(req_data);
+done:
+ if (rq)
+ blk_end_request(rq, ret, len);
+ return ret;
+}
+
+/*
+ * Ceph osd op callback
+ */
+static void rbd_req_cb(struct ceph_osd_request *req, struct ceph_msg *msg)
+{
+ struct rbd_request *req_data = req->r_priv;
+ struct ceph_osd_reply_head *replyhead;
+ struct ceph_osd_op *op;
+ __s32 rc;
+ u64 bytes;
+ int read_op;
+
+ /* parse reply */
+ replyhead = msg->front.iov_base;
+ WARN_ON(le32_to_cpu(replyhead->num_ops) == 0);
+ op = (void *)(replyhead + 1);
+ rc = le32_to_cpu(replyhead->result);
+ bytes = le64_to_cpu(op->extent.length);
+
+ dout("rbd_req_cb bytes=%lld rc=%d\n", bytes, rc);
+
+ read_op = (le32_to_cpu(op->op) == CEPH_OSD_OP_READ);
+
+ if (rc == -ENOENT && read_op) {
+ zero_bio_chain(req_data->bio, 0);
+ rc = 0;
+ } else if (rc == 0 && read_op && bytes < req_data->len) {
+ zero_bio_chain(req_data->bio, bytes);
+ bytes = req_data->len;
+ }
+
+ blk_end_request(req_data->rq, rc, bytes);
+
+ if (req_data->bio)
+ bio_chain_put(req_data->bio);
+
+ ceph_osdc_put_request(req);
+ kfree(req_data);
+}
+
+/*
+ * Do a synchronous ceph osd operation
+ */
+static int rbd_req_sync_op(struct rbd_device *dev,
+ int opcode, int flags,
+ int num_reply,
+ const char *obj,
+ u64 ofs, u64 len,
+ char *buf)
+{
+ int ret;
+ struct page **pages;
+ int num_pages;
+
+ num_pages = calc_pages_for(ofs , len);
+ pages = ceph_alloc_page_vector(num_pages, GFP_KERNEL);
+ if (!pages)
+ return -ENOMEM;
+
+ if (flags & CEPH_OSD_FLAG_WRITE) {
+ ret = ceph_copy_to_page_vector(pages, buf, ofs, len);
+ if (ret < 0)
+ goto done;
+ }
+
+ ret = rbd_do_request(NULL, dev, obj, ofs, len, NULL,
+ pages, num_pages,
+ opcode,
+ flags,
+ 2,
+ NULL);
+ if (ret < 0)
+ goto done;
+
+ if (flags & CEPH_OSD_FLAG_READ)
+ ret = ceph_copy_from_page_vector(pages, buf, ofs, len);
+
+done:
+ ceph_release_page_vector(pages, num_pages);
+ return ret;
+}
+
+/*
+ * Do an asynchronous ceph osd operation
+ */
+static int rbd_do_op(struct request *rq,
+ struct rbd_device *rbd_dev ,
+ int opcode, int flags, int num_reply,
+ u64 ofs, u64 len,
+ struct bio *bio)
+{
+ char *seg_name;
+ u64 seg_ofs;
+ u64 seg_len;
+ int ret;
+
+ seg_name = kmalloc(RBD_MAX_SEG_NAME_SIZE + 1, GFP_NOIO);
+ if (!seg_name)
+ return -ENOMEM;
+
+ seg_len = rbd_get_segment(rbd_dev->header,
+ rbd_dev->obj,
+ ofs, len,
+ seg_name, &seg_ofs);
+ if (seg_len < 0)
+ return seg_len;
+
+ /* we've taken care of segment sizes earlier when we
+ cloned the bios. We should never have a segment
+ truncated at this point */
+ BUG_ON(seg_len < len);
+
+ ret = rbd_do_request(rq, rbd_dev,
+ seg_name, seg_ofs, seg_len,
+ bio,
+ NULL, 0,
+ opcode,
+ flags,
+ num_reply,
+ rbd_req_cb);
+ kfree(seg_name);
+ return ret;
+}
+
+/*
+ * Request async osd write
+ */
+static int rbd_req_write(struct request *rq,
+ struct rbd_device *rbd_dev,
+ u64 ofs, u64 len,
+ struct bio *bio)
+{
+ return rbd_do_op(rq, rbd_dev,
+ CEPH_OSD_OP_WRITE,
+ CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK,
+ 2,
+ ofs, len, bio);
+}
+
+/*
+ * Request sync osd write
+ */
+static int __attribute__ ((unused))
+rbd_req_sync_write(struct rbd_device *dev,
+ const char *obj,
+ u64 ofs, u64 len,
+ char *buf)
+{
+ return rbd_req_sync_op(dev,
+ CEPH_OSD_OP_WRITE,
+ CEPH_OSD_FLAG_WRITE | CEPH_OSD_FLAG_ONDISK,
+ 2, obj, ofs, len, buf);
+}
+
+/*
+ * Request async osd read
+ */
+static int rbd_req_read(struct request *rq,
+ struct rbd_device *rbd_dev,
+ u64 ofs, u64 len,
+ struct bio *bio)
+{
+ return rbd_do_op(rq, rbd_dev,
+ CEPH_OSD_OP_READ,
+ CEPH_OSD_FLAG_READ,
+ 2,
+ ofs, len, bio);
+}
+
+/*
+ * Request sync osd read
+ */
+static int rbd_req_sync_read(struct rbd_device *dev,
+ const char *obj,
+ u64 ofs, u64 len,
+ char *buf)
+{
+ return rbd_req_sync_op(dev,
+ CEPH_OSD_OP_READ,
+ CEPH_OSD_FLAG_READ,
+ 1, obj, ofs, len, buf);
+}
+
+/*
+ * block device queue callback
+ */
+static void rbd_rq_fn(struct request_queue *q)
+{
+ struct rbd_device *rbd_dev = q->queuedata;
+ struct request *rq;
+ struct bio_pair *bp = NULL;
+
+ rq = blk_fetch_request(q);
+
+ while (1) {
+ struct bio *bio;
+ struct bio *rq_bio, *next_bio = NULL;
+ bool do_write, do_flush;
+ int size, op_size = 0;
+ u64 ofs;
+
+ /* peek at request from block layer */
+ if (!rq)
+ break;
+
+ dout("fetched request\n");
+
+ /* filter out block requests we don't understand */
+ if (!blk_fs_request(rq) && !blk_barrier_rq(rq)) {
+ blk_end_request_all(rq, 0);
+ continue;
+ }
+
+ /* deduce our operation (read, write, flush) */
+ /* I wish the block layer simplified cmd_type/cmd_flags/cmd[]
+ * into a clearly defined set of RPC commands:
+ * read, write, flush, scsi command, power mgmt req,
+ * driver-specific, etc.
+ */
+ do_flush = (rq->special == (void *) 0xdeadbeefUL);
+ do_write = (rq_data_dir(rq) == WRITE);
+
+ size = blk_rq_bytes(rq);
+ ofs = blk_rq_pos(rq) * 512ULL;
+ rq_bio = rq->bio;
+
+ spin_unlock_irq(q->queue_lock);
+
+ dout("%s 0x%x bytes at 0x%llx\n",
+ do_flush ? "flush" : (do_write ? "write" : "read"),
+ size, blk_rq_pos(rq) * 512ULL);
+
+ do {
+ if (!do_flush) { /* osd_flush does not use a bio */
+ /* a bio clone to be passed down to OSD req */
+ dout("rq->bio->bi_vcnt=%d\n", rq->bio->bi_vcnt);
+ op_size = rbd_get_segment(rbd_dev->header,
+ rbd_dev->obj,
+ ofs, size,
+ NULL, NULL);
+ bio = bio_chain_clone(&rq_bio, &next_bio, &bp,
+ op_size, GFP_ATOMIC);
+ if (!bio)
+ break;
+ } else {
+ bio = NULL;
+ }
+
+ /* init OSD command: flush, write or read */
+ if (do_flush)
+ rbd_req_flush_object(rq, rbd_dev->obj,
+ 0, 0);
+ else if (do_write)
+ rbd_req_write(rq, rbd_dev,
+ ofs,
+ op_size, bio);
+ else
+ rbd_req_read(rq, rbd_dev,
+ ofs,
+ op_size, bio);
+
+ size -= op_size;
+ ofs += op_size;
+
+ rq_bio = next_bio;
+ } while (size > 0);
+
+ if (bp)
+ bio_pair_release(bp);
+
+ spin_lock_irq(q->queue_lock);
+
+ /* remove the special 'flush' marker, now that the command
+ * is executing */
+ rq->special = NULL;
+
+ rq = blk_fetch_request(q);
+ }
+}
+
+/*
+ * a queue callback. Makes sure that we don't create a bio that spans across
+ * multiple osd objects. One exception would be with a single page bios,
+ * which we handle later at bio_chain_clone
+ */
+static int rbd_merge_bvec(struct request_queue *q, struct bvec_merge_data *bmd,
+ struct bio_vec *bvec)
+{
+ sector_t sector = bmd->bi_sector + get_start_sect(bmd->bi_bdev);
+ unsigned int chunk_sectors = (RBD_STRIPE_UNIT >> 9);
+ unsigned int bio_sectors = bmd->bi_size >> 9;
+ int max;
+
+ max = (chunk_sectors - ((sector & (chunk_sectors - 1))
+ + bio_sectors)) << 9;
+ if (max < 0)
+ max = 0; /* bio_add cannot handle a negative return */
+ if (max <= bvec->bv_len && bio_sectors == 0)
+ return bvec->bv_len;
+ return max;
+}
+
+static void rbd_prepare_flush(struct request_queue *q, struct request *rq)
+{
+ /*
+ * add driver-specific marker, to indicate that this request
+ * is a flush command
+ */
+ rq->special = (void *) 0xdeadbeefUL;
+}
+
+static void rbd_free_disk(struct rbd_device *rbd_dev)
+{
+ struct gendisk *disk = rbd_dev->disk;
+
+ if (!disk)
+ return;
+
+ if (disk->flags & GENHD_FL_UP)
+ del_gendisk(disk);
+ if (disk->queue)
+ blk_cleanup_queue(disk->queue);
+ put_disk(disk);
+}
+
+static int rbd_read_header(struct rbd_device *rbd_dev,
+ struct rbd_obj_header **header)
+{
+ ssize_t rc;
+ char *obj_md_name;
+ struct rbd_obj_header_ondisk *dh;
+ int snap_count = 0;
+
+ obj_md_name = kmalloc(strlen(rbd_dev->obj) + sizeof(RBD_SUFFIX),
+ GFP_KERNEL);
+ if (!obj_md_name)
+ return -ENOMEM;
+ sprintf(obj_md_name, "%s%s", rbd_dev->obj, RBD_SUFFIX);
+
+ while (1) {
+ dh = kmalloc(sizeof(*dh) + snap_count * sizeof(u32),
+ GFP_KERNEL);
+ if (!dh)
+ goto out_obj_md;
+
+ rc = rbd_req_sync_read(rbd_dev,
+ obj_md_name,
+ 0, sizeof(*dh),
+ (char *)dh);
+ if (rc < 0)
+ goto out_dh;
+
+ rc = rbd_header_from_disk(header, dh, GFP_KERNEL);
+ if (rc < 0)
+ goto out_dh;
+
+ if (snap_count != (*header)->snap_count) {
+ snap_count = (*header)->snap_count;
+ kfree(*header);
+ kfree(dh);
+ continue;
+ }
+ break;
+ }
+
+out_dh:
+ kfree(dh);
+out_obj_md:
+ kfree(obj_md_name);
+ return rc;
+}
+
+static int rbd_init_disk(struct rbd_device *rbd_dev)
+{
+ struct gendisk *disk;
+ struct request_queue *q;
+ int rc;
+ u64 total_size;
+
+ /* contact OSD, request size info about the object being mapped */
+ rc = rbd_read_header(rbd_dev, &rbd_dev->header);
+ if (rc)
+ return rc;
+
+ total_size = rbd_dev->header->image_size;
+
+ /* create gendisk info */
+ rc = -ENOMEM;
+ disk = alloc_disk(RBD_MINORS_PER_MAJOR);
+ if (!disk)
+ goto out;
+
+ sprintf(disk->disk_name, DRV_NAME "%d", rbd_dev->id);
+ disk->major = rbd_dev->major;
+ disk->first_minor = 0;
+ disk->fops = &rbd_bd_ops;
+ disk->private_data = rbd_dev;
+
+ /* init rq */
+ rc = -ENOMEM;
+ q = blk_init_queue(rbd_rq_fn, &rbd_dev->lock);
+ if (!q)
+ goto out_disk;
+ blk_queue_ordered(q, QUEUE_ORDERED_DRAIN_FLUSH, rbd_prepare_flush);
+ blk_queue_merge_bvec(q, rbd_merge_bvec);
+ disk->queue = q;
+
+ q->queuedata = rbd_dev;
+
+ rbd_dev->disk = disk;
+ rbd_dev->q = q;
+
+ /* finally, announce the disk to the world */
+ set_capacity(disk, total_size / 512ULL);
+ add_disk(disk);
+
+ pr_info("%s: added with size 0x%llx\n",
+ disk->disk_name, (unsigned long long)total_size);
+ return 0;
+
+out_disk:
+ put_disk(disk);
+out:
+ return rc;
+}
+
+/********************************************************************
+ * /sys/class/rbd/
+ * add map rados objects to blkdev
+ * remove unmap rados objects
+ * list show mappings
+ *******************************************************************/
+
+static void class_rbd_release(struct class *cls)
+{
+ kfree(cls);
+}
+
+static ssize_t class_rbd_list(struct class *c,
+ struct class_attribute *attr,
+ char *data)
+{
+ int n = 0;
+ struct list_head *tmp;
+
+ mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
+
+ list_for_each(tmp, &rbddev_list) {
+ struct rbd_device *rbd_dev;
+
+ rbd_dev = list_entry(tmp, struct rbd_device, node);
+ n += sprintf(data+n, "%d %d %d %s\n",
+ rbd_dev->id,
+ rbd_dev->major,
+ rbd_dev->poolid,
+ rbd_dev->obj);
+ }
+
+ mutex_unlock(&ctl_mutex);
+ return n;
+}
+
+static ssize_t class_rbd_add(struct class *c,
+ struct class_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct rbd_device *rbd_dev;
+ ssize_t rc = -ENOMEM;
+ int irc, new_id = 0;
+ struct list_head *tmp;
+ char *mon_dev_name;
+ char *opt;
+
+ if (!try_module_get(THIS_MODULE))
+ return -ENODEV;
+
+ mon_dev_name = kmalloc(RBD_MAX_OPT_LEN, GFP_KERNEL);
+ if (!mon_dev_name)
+ goto err_out_mod;
+
+ opt = kmalloc(RBD_MAX_OPT_LEN, GFP_KERNEL);
+ if (!opt)
+ goto err_mon_dev;
+
+ /* new rbd_device object */
+ rbd_dev = kzalloc(sizeof(*rbd_dev), GFP_KERNEL);
+ if (!rbd_dev)
+ goto err_out_opt;
+
+ /* static rbd_device initialization */
+ spin_lock_init(&rbd_dev->lock);
+ INIT_LIST_HEAD(&rbd_dev->node);
+
+ /* generate unique id: find highest unique id, add one */
+ mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
+
+ list_for_each(tmp, &rbddev_list) {
+ struct rbd_device *rbd_dev;
+
+ rbd_dev = list_entry(tmp, struct rbd_device, node);
+ if (rbd_dev->id >= new_id)
+ new_id = rbd_dev->id + 1;
+ }
+
+ rbd_dev->id = new_id;
+
+ /* add to global list */
+ list_add_tail(&rbd_dev->node, &rbddev_list);
+
+ /* parse add command */
+ if (sscanf(buf, "%" __stringify(RBD_MAX_OPT_LEN) "s "
+ "%" __stringify(RBD_MAX_OPT_LEN) "s "
+ "%d %" __stringify(RBD_MAX_OBJ_NAME_SIZE) "s",
+ mon_dev_name, opt, &rbd_dev->poolid,
+ rbd_dev->obj) != 4) {
+ rc = -EINVAL;
+ goto err_out_slot;
+ }
+
+ rbd_dev->obj_len = strlen(rbd_dev->obj);
+
+ /* initialize rest of new object */
+ snprintf(rbd_dev->name, DEV_NAME_LEN, "%d", rbd_dev->id);
+ rc = rbd_get_client(rbd_dev, mon_dev_name, opt);
+ if (rc < 0)
+ goto err_out_slot;
+
+ mutex_unlock(&ctl_mutex);
+
+ /* register our block device */
+ irc = register_blkdev(0, rbd_dev->name);
+ if (irc < 0) {
+ rc = irc;
+ goto err_out_slot;
+ }
+ rbd_dev->major = irc;
+
+ /* set up and announce blkdev mapping */
+ rc = rbd_init_disk(rbd_dev);
+ if (rc)
+ goto err_out_blkdev;
+
+ return count;
+
+err_out_blkdev:
+ unregister_blkdev(rbd_dev->major, rbd_dev->name);
+err_out_slot:
+ mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
+ list_del_init(&rbd_dev->node);
+ mutex_unlock(&ctl_mutex);
+
+ kfree(rbd_dev);
+err_out_opt:
+ kfree(opt);
+err_mon_dev:
+ kfree(mon_dev_name);
+err_out_mod:
+ dout("Error adding device %s\n", buf);
+ module_put(THIS_MODULE);
+ return rc;
+}
+
+static ssize_t class_rbd_remove(struct class *c,
+ struct class_attribute *attr,
+ const char *buf,
+ size_t count)
+{
+ struct rbd_device *rbd_dev = NULL;
+ int target_id, rc;
+ unsigned long ul;
+ struct list_head *tmp;
+
+ rc = strict_strtoul(buf, 10, &ul);
+ if (rc)
+ return rc;
+
+ /* convert to int; abort if we lost anything in the conversion */
+ target_id = (int) ul;
+ if (target_id != ul)
+ return -EINVAL;
+
+ /* remove object from list immediately */
+ mutex_lock_nested(&ctl_mutex, SINGLE_DEPTH_NESTING);
+
+ list_for_each(tmp, &rbddev_list) {
+ rbd_dev = list_entry(tmp, struct rbd_device, node);
+ if (rbd_dev->id == target_id) {
+ list_del_init(&rbd_dev->node);
+ break;
+ }
+ rbd_dev = NULL;
+ }
+
+ mutex_unlock(&ctl_mutex);
+
+ if (!rbd_dev)
+ return -ENOENT;
+
+ rbd_put_client(rbd_dev);
+
+ /* clean up and free blkdev and associated OSD connection */
+ rbd_free_disk(rbd_dev);
+ unregister_blkdev(rbd_dev->major, rbd_dev->name);
+ kfree(rbd_dev);
+
+ /* release module ref */
+ module_put(THIS_MODULE);
+
+ return count;
+}
+
+static struct class_attribute class_rbd_attrs[] = {
+ __ATTR(add, 0200, NULL, class_rbd_add),
+ __ATTR(remove, 0200, NULL, class_rbd_remove),
+ __ATTR(list, 0444, class_rbd_list, NULL),
+ __ATTR_NULL
+};
+
+/*
+ * create control files in sysfs
+ * /sys/class/rbd/...
+ */
+static int rbd_sysfs_init(void)
+{
+ int ret = -ENOMEM;
+
+ class_rbd = kzalloc(sizeof(*class_rbd), GFP_KERNEL);
+ if (!class_rbd)
+ goto out;
+
+ class_rbd->name = DRV_NAME;
+ class_rbd->owner = THIS_MODULE;
+ class_rbd->class_release = class_rbd_release;
+ class_rbd->class_attrs = class_rbd_attrs;
+
+ ret = class_register(class_rbd);
+ if (ret)
+ goto out_class;
+ return 0;
+
+out_class:
+ kfree(class_rbd);
+ class_rbd = NULL;
+ pr_err(DRV_NAME ": failed to create class rbd\n");
+out:
+ return ret;
+}
+
+static void rbd_sysfs_cleanup(void)
+{
+ if (class_rbd)
+ class_destroy(class_rbd);
+ class_rbd = NULL;
+}
+
+int __init rbd_init(void)
+{
+ int rc;
+
+ rc = rbd_sysfs_init();
+ if (rc)
+ return rc;
+ spin_lock_init(&node_lock);
+ pr_info("loaded " DRV_NAME_LONG);
+ return 0;
+}
+
+void __exit rbd_exit(void)
+{
+ rbd_sysfs_cleanup();
+}
diff --git a/fs/ceph/rbd.h b/fs/ceph/rbd.h
new file mode 100644
index 0000000..68e0a5c
--- /dev/null
+++ b/fs/ceph/rbd.h
@@ -0,0 +1,8 @@
+#ifndef _FS_CEPH_RBD
+#define _FS_CEPH_RBD
+
+extern void rbd_set_osdc(struct ceph_osd_client *o);
+extern int __init rbd_init(void);
+extern void __exit rbd_exit(void);
+
+#endif
diff --git a/fs/ceph/super.c b/fs/ceph/super.c
index 52e9e86..9a73b25 100644
--- a/fs/ceph/super.c
+++ b/fs/ceph/super.c
@@ -17,6 +17,7 @@
#include "super.h"
#include "mon_client.h"
#include "auth.h"
+#include "rbd.h"
/*
* Ceph superblock operations
@@ -1079,8 +1080,14 @@ static int __init init_ceph(void)
pr_info("loaded %d.%d.%d (mon/mds/osd proto %d/%d/%d)\n",
CEPH_VERSION_MAJOR, CEPH_VERSION_MINOR, CEPH_VERSION_PATCH,
CEPH_MONC_PROTOCOL, CEPH_MDSC_PROTOCOL, CEPH_OSDC_PROTOCOL);
+
+ ret = rbd_init();
+ if (ret)
+ goto out_fs;
return 0;
+out_fs:
+ unregister_filesystem(&ceph_fs_type);
out_icache:
destroy_caches();
out_msgr:
@@ -1094,6 +1101,7 @@ out:
static void __exit exit_ceph(void)
{
dout("exit_ceph\n");
+ rbd_exit();
unregister_filesystem(&ceph_fs_type);
ceph_caps_finalize();
destroy_caches();
--
1.5.6.5
--
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