ceph: OSD client
The OSD client is responsible for reading and writing data from/to the
object storage pool. This includes determining where objects are
stored in the cluster, and ensuring that requests are retried or
redirected in the event of a node failure or data migration.
If an OSD does not respond before a timeout expires, keepalive
messages are sent across the lossless, ordered communications channel
to ensure that any break in the TCP is discovered. If the session
does reset, a reconnection is attempted and affected requests are
resent (by the message transport layer).
Signed-off-by: Sage Weil <sage@newdream.net>
diff --git a/fs/ceph/osd_client.c b/fs/ceph/osd_client.c
new file mode 100644
index 0000000..978593a
--- /dev/null
+++ b/fs/ceph/osd_client.c
@@ -0,0 +1,1294 @@
+#include "ceph_debug.h"
+
+#include <linux/err.h>
+#include <linux/highmem.h>
+#include <linux/mm.h>
+#include <linux/pagemap.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+
+#include "super.h"
+#include "osd_client.h"
+#include "messenger.h"
+#include "decode.h"
+
+const static struct ceph_connection_operations osd_con_ops;
+
+static void kick_requests(struct ceph_osd_client *osdc, struct ceph_osd *osd);
+
+/*
+ * Implement client access to distributed object storage cluster.
+ *
+ * All data objects are stored within a cluster/cloud of OSDs, or
+ * "object storage devices." (Note that Ceph OSDs have _nothing_ to
+ * do with the T10 OSD extensions to SCSI.) Ceph OSDs are simply
+ * remote daemons serving up and coordinating consistent and safe
+ * access to storage.
+ *
+ * Cluster membership and the mapping of data objects onto storage devices
+ * are described by the osd map.
+ *
+ * We keep track of pending OSD requests (read, write), resubmit
+ * requests to different OSDs when the cluster topology/data layout
+ * change, or retry the affected requests when the communications
+ * channel with an OSD is reset.
+ */
+
+/*
+ * calculate the mapping of a file extent onto an object, and fill out the
+ * request accordingly. shorten extent as necessary if it crosses an
+ * object boundary.
+ *
+ * fill osd op in request message.
+ */
+static void calc_layout(struct ceph_osd_client *osdc,
+ struct ceph_vino vino, struct ceph_file_layout *layout,
+ u64 off, u64 *plen,
+ struct ceph_osd_request *req)
+{
+ struct ceph_osd_request_head *reqhead = req->r_request->front.iov_base;
+ struct ceph_osd_op *op = (void *)(reqhead + 1);
+ u64 orig_len = *plen;
+ u64 objoff, objlen; /* extent in object */
+ u64 bno;
+
+ reqhead->snapid = cpu_to_le64(vino.snap);
+
+ /* object extent? */
+ ceph_calc_file_object_mapping(layout, off, plen, &bno,
+ &objoff, &objlen);
+ if (*plen < orig_len)
+ dout(" skipping last %llu, final file extent %llu~%llu\n",
+ orig_len - *plen, off, *plen);
+
+ sprintf(req->r_oid, "%llx.%08llx", vino.ino, bno);
+ req->r_oid_len = strlen(req->r_oid);
+
+ op->extent.offset = cpu_to_le64(objoff);
+ op->extent.length = cpu_to_le64(objlen);
+ req->r_num_pages = calc_pages_for(off, *plen);
+
+ dout("calc_layout %s (%d) %llu~%llu (%d pages)\n",
+ req->r_oid, req->r_oid_len, objoff, objlen, req->r_num_pages);
+}
+
+
+/*
+ * requests
+ */
+void ceph_osdc_put_request(struct ceph_osd_request *req)
+{
+ dout("osdc put_request %p %d -> %d\n", req, atomic_read(&req->r_ref),
+ atomic_read(&req->r_ref)-1);
+ BUG_ON(atomic_read(&req->r_ref) <= 0);
+ if (atomic_dec_and_test(&req->r_ref)) {
+ if (req->r_request)
+ ceph_msg_put(req->r_request);
+ if (req->r_reply)
+ ceph_msg_put(req->r_reply);
+ if (req->r_own_pages)
+ ceph_release_page_vector(req->r_pages,
+ req->r_num_pages);
+ ceph_put_snap_context(req->r_snapc);
+ if (req->r_mempool)
+ mempool_free(req, req->r_osdc->req_mempool);
+ else
+ kfree(req);
+ }
+}
+
+/*
+ * build new request AND message, calculate layout, and adjust file
+ * extent as needed.
+ *
+ * if the file was recently truncated, we include information about its
+ * old and new size so that the object can be updated appropriately. (we
+ * avoid synchronously deleting truncated objects because it's slow.)
+ *
+ * if @do_sync, include a 'startsync' command so that the osd will flush
+ * data quickly.
+ */
+struct ceph_osd_request *ceph_osdc_new_request(struct ceph_osd_client *osdc,
+ struct ceph_file_layout *layout,
+ struct ceph_vino vino,
+ u64 off, u64 *plen,
+ int opcode, int flags,
+ struct ceph_snap_context *snapc,
+ int do_sync,
+ u32 truncate_seq,
+ u64 truncate_size,
+ struct timespec *mtime,
+ bool use_mempool, int num_reply)
+{
+ struct ceph_osd_request *req;
+ struct ceph_msg *msg;
+ struct ceph_osd_request_head *head;
+ struct ceph_osd_op *op;
+ void *p;
+ int do_trunc = truncate_seq && (off + *plen > truncate_size);
+ int num_op = 1 + do_sync + do_trunc;
+ size_t msg_size = sizeof(*head) + num_op*sizeof(*op);
+ int err, i;
+ u64 prevofs;
+
+ if (use_mempool) {
+ req = mempool_alloc(osdc->req_mempool, GFP_NOFS);
+ memset(req, 0, sizeof(*req));
+ } else {
+ req = kzalloc(sizeof(*req), GFP_NOFS);
+ }
+ if (req == NULL)
+ return ERR_PTR(-ENOMEM);
+
+ err = ceph_msgpool_resv(&osdc->msgpool_op_reply, num_reply);
+ if (err) {
+ ceph_osdc_put_request(req);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ req->r_osdc = osdc;
+ req->r_mempool = use_mempool;
+ atomic_set(&req->r_ref, 1);
+ init_completion(&req->r_completion);
+ init_completion(&req->r_safe_completion);
+ INIT_LIST_HEAD(&req->r_unsafe_item);
+ req->r_flags = flags;
+
+ WARN_ON((flags & (CEPH_OSD_FLAG_READ|CEPH_OSD_FLAG_WRITE)) == 0);
+
+ /* create message; allow space for oid */
+ msg_size += 40;
+ if (snapc)
+ msg_size += sizeof(u64) * snapc->num_snaps;
+ if (use_mempool)
+ msg = ceph_msgpool_get(&osdc->msgpool_op);
+ else
+ msg = ceph_msg_new(CEPH_MSG_OSD_OP, msg_size, 0, 0, NULL);
+ if (IS_ERR(msg)) {
+ ceph_msgpool_resv(&osdc->msgpool_op_reply, num_reply);
+ ceph_osdc_put_request(req);
+ return ERR_PTR(PTR_ERR(msg));
+ }
+ msg->hdr.type = cpu_to_le16(CEPH_MSG_OSD_OP);
+ memset(msg->front.iov_base, 0, msg->front.iov_len);
+ head = msg->front.iov_base;
+ op = (void *)(head + 1);
+ p = (void *)(op + num_op);
+
+ req->r_request = msg;
+ req->r_snapc = ceph_get_snap_context(snapc);
+
+ head->client_inc = cpu_to_le32(1); /* always, for now. */
+ head->flags = cpu_to_le32(flags);
+ if (flags & CEPH_OSD_FLAG_WRITE)
+ ceph_encode_timespec(&head->mtime, mtime);
+ head->num_ops = cpu_to_le16(num_op);
+ op->op = cpu_to_le16(opcode);
+
+ /* calculate max write size */
+ calc_layout(osdc, vino, layout, off, plen, req);
+ req->r_file_layout = *layout; /* keep a copy */
+
+ if (flags & CEPH_OSD_FLAG_WRITE) {
+ req->r_request->hdr.data_off = cpu_to_le16(off);
+ req->r_request->hdr.data_len = cpu_to_le32(*plen);
+ op->payload_len = cpu_to_le32(*plen);
+ }
+
+ /* fill in oid */
+ head->object_len = cpu_to_le32(req->r_oid_len);
+ memcpy(p, req->r_oid, req->r_oid_len);
+ p += req->r_oid_len;
+
+ /* additional ops */
+ if (do_trunc) {
+ op++;
+ op->op = cpu_to_le16(opcode == CEPH_OSD_OP_READ ?
+ CEPH_OSD_OP_MASKTRUNC : CEPH_OSD_OP_SETTRUNC);
+ op->trunc.truncate_seq = cpu_to_le32(truncate_seq);
+ prevofs = le64_to_cpu((op-1)->extent.offset);
+ op->trunc.truncate_size = cpu_to_le64(truncate_size -
+ (off-prevofs));
+ }
+ if (do_sync) {
+ op++;
+ op->op = cpu_to_le16(CEPH_OSD_OP_STARTSYNC);
+ }
+ if (snapc) {
+ head->snap_seq = cpu_to_le64(snapc->seq);
+ head->num_snaps = cpu_to_le32(snapc->num_snaps);
+ for (i = 0; i < snapc->num_snaps; i++) {
+ put_unaligned_le64(snapc->snaps[i], p);
+ p += sizeof(u64);
+ }
+ }
+
+ BUG_ON(p > msg->front.iov_base + msg->front.iov_len);
+ return req;
+}
+
+/*
+ * We keep osd requests in an rbtree, sorted by ->r_tid.
+ */
+static void __insert_request(struct ceph_osd_client *osdc,
+ struct ceph_osd_request *new)
+{
+ struct rb_node **p = &osdc->requests.rb_node;
+ struct rb_node *parent = NULL;
+ struct ceph_osd_request *req = NULL;
+
+ while (*p) {
+ parent = *p;
+ req = rb_entry(parent, struct ceph_osd_request, r_node);
+ if (new->r_tid < req->r_tid)
+ p = &(*p)->rb_left;
+ else if (new->r_tid > req->r_tid)
+ p = &(*p)->rb_right;
+ else
+ BUG();
+ }
+
+ rb_link_node(&new->r_node, parent, p);
+ rb_insert_color(&new->r_node, &osdc->requests);
+}
+
+static struct ceph_osd_request *__lookup_request(struct ceph_osd_client *osdc,
+ u64 tid)
+{
+ struct ceph_osd_request *req;
+ struct rb_node *n = osdc->requests.rb_node;
+
+ while (n) {
+ req = rb_entry(n, struct ceph_osd_request, r_node);
+ if (tid < req->r_tid)
+ n = n->rb_left;
+ else if (tid > req->r_tid)
+ n = n->rb_right;
+ else
+ return req;
+ }
+ return NULL;
+}
+
+static struct ceph_osd_request *
+__lookup_request_ge(struct ceph_osd_client *osdc,
+ u64 tid)
+{
+ struct ceph_osd_request *req;
+ struct rb_node *n = osdc->requests.rb_node;
+
+ while (n) {
+ req = rb_entry(n, struct ceph_osd_request, r_node);
+ if (tid < req->r_tid) {
+ if (!n->rb_left)
+ return req;
+ n = n->rb_left;
+ } else if (tid > req->r_tid) {
+ n = n->rb_right;
+ } else {
+ return req;
+ }
+ }
+ return NULL;
+}
+
+
+/*
+ * The messaging layer will reconnect to the osd as needed. If the
+ * session has dropped, the OSD will have dropped the session state,
+ * and we'll get notified by the messaging layer. If that happens, we
+ * need to resubmit all requests for that osd.
+ */
+static void osd_reset(struct ceph_connection *con)
+{
+ struct ceph_osd *osd = con->private;
+ struct ceph_osd_client *osdc;
+
+ if (!osd)
+ return;
+ dout("osd_reset osd%d\n", osd->o_osd);
+ osdc = osd->o_osdc;
+ osd->o_incarnation++;
+ down_read(&osdc->map_sem);
+ kick_requests(osdc, osd);
+ up_read(&osdc->map_sem);
+}
+
+/*
+ * Track open sessions with osds.
+ */
+static struct ceph_osd *create_osd(struct ceph_osd_client *osdc)
+{
+ struct ceph_osd *osd;
+
+ osd = kzalloc(sizeof(*osd), GFP_NOFS);
+ if (!osd)
+ return NULL;
+
+ atomic_set(&osd->o_ref, 1);
+ osd->o_osdc = osdc;
+ INIT_LIST_HEAD(&osd->o_requests);
+ osd->o_incarnation = 1;
+
+ ceph_con_init(osdc->client->msgr, &osd->o_con);
+ osd->o_con.private = osd;
+ osd->o_con.ops = &osd_con_ops;
+ osd->o_con.peer_name.type = CEPH_ENTITY_TYPE_OSD;
+ return osd;
+}
+
+static struct ceph_osd *get_osd(struct ceph_osd *osd)
+{
+ if (atomic_inc_not_zero(&osd->o_ref)) {
+ dout("get_osd %p %d -> %d\n", osd, atomic_read(&osd->o_ref)-1,
+ atomic_read(&osd->o_ref));
+ return osd;
+ } else {
+ dout("get_osd %p FAIL\n", osd);
+ return NULL;
+ }
+}
+
+static void put_osd(struct ceph_osd *osd)
+{
+ dout("put_osd %p %d -> %d\n", osd, atomic_read(&osd->o_ref),
+ atomic_read(&osd->o_ref) - 1);
+ if (atomic_dec_and_test(&osd->o_ref)) {
+ ceph_con_shutdown(&osd->o_con);
+ kfree(osd);
+ }
+}
+
+/*
+ * remove an osd from our map
+ */
+static void remove_osd(struct ceph_osd_client *osdc, struct ceph_osd *osd)
+{
+ dout("remove_osd %p\n", osd);
+ BUG_ON(!list_empty(&osd->o_requests));
+ rb_erase(&osd->o_node, &osdc->osds);
+ ceph_con_close(&osd->o_con);
+ put_osd(osd);
+}
+
+/*
+ * reset osd connect
+ */
+static int reset_osd(struct ceph_osd_client *osdc, struct ceph_osd *osd)
+{
+ int ret = 0;
+
+ dout("reset_osd %p osd%d\n", osd, osd->o_osd);
+ if (list_empty(&osd->o_requests)) {
+ remove_osd(osdc, osd);
+ } else {
+ ceph_con_close(&osd->o_con);
+ ceph_con_open(&osd->o_con, &osdc->osdmap->osd_addr[osd->o_osd]);
+ osd->o_incarnation++;
+ }
+ return ret;
+}
+
+static void __insert_osd(struct ceph_osd_client *osdc, struct ceph_osd *new)
+{
+ struct rb_node **p = &osdc->osds.rb_node;
+ struct rb_node *parent = NULL;
+ struct ceph_osd *osd = NULL;
+
+ while (*p) {
+ parent = *p;
+ osd = rb_entry(parent, struct ceph_osd, o_node);
+ if (new->o_osd < osd->o_osd)
+ p = &(*p)->rb_left;
+ else if (new->o_osd > osd->o_osd)
+ p = &(*p)->rb_right;
+ else
+ BUG();
+ }
+
+ rb_link_node(&new->o_node, parent, p);
+ rb_insert_color(&new->o_node, &osdc->osds);
+}
+
+static struct ceph_osd *__lookup_osd(struct ceph_osd_client *osdc, int o)
+{
+ struct ceph_osd *osd;
+ struct rb_node *n = osdc->osds.rb_node;
+
+ while (n) {
+ osd = rb_entry(n, struct ceph_osd, o_node);
+ if (o < osd->o_osd)
+ n = n->rb_left;
+ else if (o > osd->o_osd)
+ n = n->rb_right;
+ else
+ return osd;
+ }
+ return NULL;
+}
+
+
+/*
+ * Register request, assign tid. If this is the first request, set up
+ * the timeout event.
+ */
+static void register_request(struct ceph_osd_client *osdc,
+ struct ceph_osd_request *req)
+{
+ struct ceph_osd_request_head *head = req->r_request->front.iov_base;
+
+ mutex_lock(&osdc->request_mutex);
+ req->r_tid = ++osdc->last_tid;
+ head->tid = cpu_to_le64(req->r_tid);
+
+ dout("register_request %p tid %lld\n", req, req->r_tid);
+ __insert_request(osdc, req);
+ ceph_osdc_get_request(req);
+ osdc->num_requests++;
+
+ req->r_timeout_stamp =
+ jiffies + osdc->client->mount_args.osd_timeout*HZ;
+
+ if (osdc->num_requests == 1) {
+ osdc->timeout_tid = req->r_tid;
+ dout(" timeout on tid %llu at %lu\n", req->r_tid,
+ req->r_timeout_stamp);
+ schedule_delayed_work(&osdc->timeout_work,
+ round_jiffies_relative(req->r_timeout_stamp - jiffies));
+ }
+ mutex_unlock(&osdc->request_mutex);
+}
+
+/*
+ * called under osdc->request_mutex
+ */
+static void __unregister_request(struct ceph_osd_client *osdc,
+ struct ceph_osd_request *req)
+{
+ dout("__unregister_request %p tid %lld\n", req, req->r_tid);
+ rb_erase(&req->r_node, &osdc->requests);
+ osdc->num_requests--;
+
+ list_del_init(&req->r_osd_item);
+ if (list_empty(&req->r_osd->o_requests))
+ remove_osd(osdc, req->r_osd);
+ req->r_osd = NULL;
+
+ ceph_osdc_put_request(req);
+
+ if (req->r_tid == osdc->timeout_tid) {
+ if (osdc->num_requests == 0) {
+ dout("no requests, canceling timeout\n");
+ osdc->timeout_tid = 0;
+ cancel_delayed_work(&osdc->timeout_work);
+ } else {
+ req = rb_entry(rb_first(&osdc->requests),
+ struct ceph_osd_request, r_node);
+ osdc->timeout_tid = req->r_tid;
+ dout("rescheduled timeout on tid %llu at %lu\n",
+ req->r_tid, req->r_timeout_stamp);
+ schedule_delayed_work(&osdc->timeout_work,
+ round_jiffies_relative(req->r_timeout_stamp -
+ jiffies));
+ }
+ }
+}
+
+/*
+ * Cancel a previously queued request message
+ */
+static void __cancel_request(struct ceph_osd_request *req)
+{
+ if (req->r_sent) {
+ ceph_con_revoke(&req->r_osd->o_con, req->r_request);
+ req->r_sent = 0;
+ }
+}
+
+/*
+ * Pick an osd (the first 'up' osd in the pg), allocate the osd struct
+ * (as needed), and set the request r_osd appropriately. If there is
+ * no up osd, set r_osd to NULL.
+ *
+ * Return 0 if unchanged, 1 if changed, or negative on error.
+ *
+ * Caller should hold map_sem for read and request_mutex.
+ */
+static int __map_osds(struct ceph_osd_client *osdc,
+ struct ceph_osd_request *req)
+{
+ struct ceph_osd_request_head *reqhead = req->r_request->front.iov_base;
+ union ceph_pg pgid;
+ int o = -1;
+ int err;
+ struct ceph_osd *newosd = NULL;
+
+ dout("map_osds %p tid %lld\n", req, req->r_tid);
+ err = ceph_calc_object_layout(&reqhead->layout, req->r_oid,
+ &req->r_file_layout, osdc->osdmap);
+ if (err)
+ return err;
+ pgid.pg64 = le64_to_cpu(reqhead->layout.ol_pgid);
+ o = ceph_calc_pg_primary(osdc->osdmap, pgid);
+
+ if ((req->r_osd && req->r_osd->o_osd == o &&
+ req->r_sent >= req->r_osd->o_incarnation) ||
+ (req->r_osd == NULL && o == -1))
+ return 0; /* no change */
+
+ dout("map_osds tid %llu pgid %llx pool %d osd%d (was osd%d)\n",
+ req->r_tid, pgid.pg64, pgid.pg.pool, o,
+ req->r_osd ? req->r_osd->o_osd : -1);
+
+ if (req->r_osd) {
+ __cancel_request(req);
+ list_del_init(&req->r_osd_item);
+ if (list_empty(&req->r_osd->o_requests)) {
+ /* try to re-use r_osd if possible */
+ newosd = get_osd(req->r_osd);
+ remove_osd(osdc, newosd);
+ }
+ req->r_osd = NULL;
+ }
+
+ req->r_osd = __lookup_osd(osdc, o);
+ if (!req->r_osd && o >= 0) {
+ if (newosd) {
+ req->r_osd = newosd;
+ newosd = NULL;
+ } else {
+ err = -ENOMEM;
+ req->r_osd = create_osd(osdc);
+ if (!req->r_osd)
+ goto out;
+ }
+
+ dout("map_osds osd %p is osd%d\n", req->r_osd, o);
+ req->r_osd->o_osd = o;
+ req->r_osd->o_con.peer_name.num = cpu_to_le64(o);
+ __insert_osd(osdc, req->r_osd);
+
+ ceph_con_open(&req->r_osd->o_con, &osdc->osdmap->osd_addr[o]);
+ }
+
+ if (req->r_osd)
+ list_add(&req->r_osd_item, &req->r_osd->o_requests);
+ err = 1; /* osd changed */
+
+out:
+ if (newosd)
+ put_osd(newosd);
+ return err;
+}
+
+/*
+ * caller should hold map_sem (for read) and request_mutex
+ */
+static int __send_request(struct ceph_osd_client *osdc,
+ struct ceph_osd_request *req)
+{
+ struct ceph_osd_request_head *reqhead;
+ int err;
+
+ err = __map_osds(osdc, req);
+ if (err < 0)
+ return err;
+ if (req->r_osd == NULL) {
+ dout("send_request %p no up osds in pg\n", req);
+ ceph_monc_request_next_osdmap(&osdc->client->monc);
+ return 0;
+ }
+
+ dout("send_request %p tid %llu to osd%d flags %d\n",
+ req, req->r_tid, req->r_osd->o_osd, req->r_flags);
+
+ reqhead = req->r_request->front.iov_base;
+ reqhead->osdmap_epoch = cpu_to_le32(osdc->osdmap->epoch);
+ reqhead->flags |= cpu_to_le32(req->r_flags); /* e.g., RETRY */
+ reqhead->reassert_version = req->r_reassert_version;
+
+ req->r_timeout_stamp = jiffies+osdc->client->mount_args.osd_timeout*HZ;
+
+ ceph_msg_get(req->r_request); /* send consumes a ref */
+ ceph_con_send(&req->r_osd->o_con, req->r_request);
+ req->r_sent = req->r_osd->o_incarnation;
+ return 0;
+}
+
+/*
+ * Timeout callback, called every N seconds when 1 or more osd
+ * requests has been active for more than N seconds. When this
+ * happens, we ping all OSDs with requests who have timed out to
+ * ensure any communications channel reset is detected. Reset the
+ * request timeouts another N seconds in the future as we go.
+ * Reschedule the timeout event another N seconds in future (unless
+ * there are no open requests).
+ */
+static void handle_timeout(struct work_struct *work)
+{
+ struct ceph_osd_client *osdc =
+ container_of(work, struct ceph_osd_client, timeout_work.work);
+ struct ceph_osd_request *req;
+ struct ceph_osd *osd;
+ unsigned long timeout = osdc->client->mount_args.osd_timeout * HZ;
+ unsigned long next_timeout = timeout + jiffies;
+ struct rb_node *p;
+
+ dout("timeout\n");
+ down_read(&osdc->map_sem);
+
+ ceph_monc_request_next_osdmap(&osdc->client->monc);
+
+ mutex_lock(&osdc->request_mutex);
+ for (p = rb_first(&osdc->requests); p; p = rb_next(p)) {
+ req = rb_entry(p, struct ceph_osd_request, r_node);
+
+ if (req->r_resend) {
+ int err;
+
+ dout("osdc resending prev failed %lld\n", req->r_tid);
+ err = __send_request(osdc, req);
+ if (err)
+ dout("osdc failed again on %lld\n", req->r_tid);
+ else
+ req->r_resend = false;
+ continue;
+ }
+ }
+ for (p = rb_first(&osdc->osds); p; p = rb_next(p)) {
+ osd = rb_entry(p, struct ceph_osd, o_node);
+ if (list_empty(&osd->o_requests))
+ continue;
+ req = list_first_entry(&osd->o_requests,
+ struct ceph_osd_request, r_osd_item);
+ if (time_before(jiffies, req->r_timeout_stamp))
+ continue;
+
+ dout(" tid %llu (at least) timed out on osd%d\n",
+ req->r_tid, osd->o_osd);
+ req->r_timeout_stamp = next_timeout;
+ ceph_con_keepalive(&osd->o_con);
+ }
+
+ if (osdc->timeout_tid)
+ schedule_delayed_work(&osdc->timeout_work,
+ round_jiffies_relative(timeout));
+
+ mutex_unlock(&osdc->request_mutex);
+
+ up_read(&osdc->map_sem);
+}
+
+/*
+ * handle osd op reply. either call the callback if it is specified,
+ * or do the completion to wake up the waiting thread.
+ */
+static void handle_reply(struct ceph_osd_client *osdc, struct ceph_msg *msg)
+{
+ struct ceph_osd_reply_head *rhead = msg->front.iov_base;
+ struct ceph_osd_request *req;
+ u64 tid;
+ int numops, object_len, flags;
+
+ if (msg->front.iov_len < sizeof(*rhead))
+ goto bad;
+ tid = le64_to_cpu(rhead->tid);
+ numops = le32_to_cpu(rhead->num_ops);
+ object_len = le32_to_cpu(rhead->object_len);
+ if (msg->front.iov_len != sizeof(*rhead) + object_len +
+ numops * sizeof(struct ceph_osd_op))
+ goto bad;
+ dout("handle_reply %p tid %llu\n", msg, tid);
+
+ /* lookup */
+ mutex_lock(&osdc->request_mutex);
+ req = __lookup_request(osdc, tid);
+ if (req == NULL) {
+ dout("handle_reply tid %llu dne\n", tid);
+ mutex_unlock(&osdc->request_mutex);
+ return;
+ }
+ ceph_osdc_get_request(req);
+ flags = le32_to_cpu(rhead->flags);
+
+ if (req->r_reply) {
+ /*
+ * once we see the message has been received, we don't
+ * need a ref (which is only needed for revoking
+ * pages)
+ */
+ ceph_msg_put(req->r_reply);
+ req->r_reply = NULL;
+ }
+
+ if (!req->r_got_reply) {
+ unsigned bytes;
+
+ req->r_result = le32_to_cpu(rhead->result);
+ bytes = le32_to_cpu(msg->hdr.data_len);
+ dout("handle_reply result %d bytes %d\n", req->r_result,
+ bytes);
+ if (req->r_result == 0)
+ req->r_result = bytes;
+
+ /* in case this is a write and we need to replay, */
+ req->r_reassert_version = rhead->reassert_version;
+
+ req->r_got_reply = 1;
+ } else if ((flags & CEPH_OSD_FLAG_ONDISK) == 0) {
+ dout("handle_reply tid %llu dup ack\n", tid);
+ goto done;
+ }
+
+ dout("handle_reply tid %llu flags %d\n", tid, flags);
+
+ /* either this is a read, or we got the safe response */
+ if ((flags & CEPH_OSD_FLAG_ONDISK) ||
+ ((flags & CEPH_OSD_FLAG_WRITE) == 0))
+ __unregister_request(osdc, req);
+
+ mutex_unlock(&osdc->request_mutex);
+
+ if (req->r_callback)
+ req->r_callback(req, msg);
+ else
+ complete(&req->r_completion);
+
+ if (flags & CEPH_OSD_FLAG_ONDISK) {
+ if (req->r_safe_callback)
+ req->r_safe_callback(req, msg);
+ complete(&req->r_safe_completion); /* fsync waiter */
+ }
+
+done:
+ ceph_osdc_put_request(req);
+ return;
+
+bad:
+ pr_err("corrupt osd_op_reply got %d %d expected %d\n",
+ (int)msg->front.iov_len, le32_to_cpu(msg->hdr.front_len),
+ (int)sizeof(*rhead));
+}
+
+
+/*
+ * Resubmit osd requests whose osd or osd address has changed. Request
+ * a new osd map if osds are down, or we are otherwise unable to determine
+ * how to direct a request.
+ *
+ * Close connections to down osds.
+ *
+ * If @who is specified, resubmit requests for that specific osd.
+ *
+ * Caller should hold map_sem for read and request_mutex.
+ */
+static void kick_requests(struct ceph_osd_client *osdc,
+ struct ceph_osd *kickosd)
+{
+ struct ceph_osd_request *req;
+ struct rb_node *p, *n;
+ int needmap = 0;
+ int err;
+
+ dout("kick_requests osd%d\n", kickosd ? kickosd->o_osd : -1);
+ mutex_lock(&osdc->request_mutex);
+ if (!kickosd) {
+ for (p = rb_first(&osdc->osds); p; p = n) {
+ struct ceph_osd *osd =
+ rb_entry(p, struct ceph_osd, o_node);
+
+ n = rb_next(p);
+ if (!ceph_osd_is_up(osdc->osdmap, osd->o_osd) ||
+ !ceph_entity_addr_equal(&osd->o_con.peer_addr,
+ ceph_osd_addr(osdc->osdmap,
+ osd->o_osd)))
+ reset_osd(osdc, osd);
+ }
+ }
+
+ for (p = rb_first(&osdc->requests); p; p = rb_next(p)) {
+ req = rb_entry(p, struct ceph_osd_request, r_node);
+
+ if (req->r_resend) {
+ dout(" r_resend set on tid %llu\n", req->r_tid);
+ goto kick;
+ }
+ if (req->r_osd && kickosd == req->r_osd)
+ goto kick;
+
+ err = __map_osds(osdc, req);
+ if (err == 0)
+ continue; /* no change */
+ if (err < 0) {
+ /*
+ * FIXME: really, we should set the request
+ * error and fail if this isn't a 'nofail'
+ * request, but that's a fair bit more
+ * complicated to do. So retry!
+ */
+ dout(" setting r_resend on %llu\n", req->r_tid);
+ req->r_resend = true;
+ continue;
+ }
+ if (req->r_osd == NULL) {
+ dout("tid %llu maps to no valid osd\n", req->r_tid);
+ needmap++; /* request a newer map */
+ continue;
+ }
+
+kick:
+ dout("kicking tid %llu osd%d\n", req->r_tid, req->r_osd->o_osd);
+ req->r_flags |= CEPH_OSD_FLAG_RETRY;
+ err = __send_request(osdc, req);
+ if (err) {
+ dout(" setting r_resend on %llu\n", req->r_tid);
+ req->r_resend = true;
+ }
+ }
+ mutex_unlock(&osdc->request_mutex);
+
+ if (needmap) {
+ dout("%d requests for down osds, need new map\n", needmap);
+ ceph_monc_request_next_osdmap(&osdc->client->monc);
+ }
+}
+
+/*
+ * Process updated osd map.
+ *
+ * The message contains any number of incremental and full maps, normally
+ * indicating some sort of topology change in the cluster. Kick requests
+ * off to different OSDs as needed.
+ */
+void ceph_osdc_handle_map(struct ceph_osd_client *osdc, struct ceph_msg *msg)
+{
+ void *p, *end, *next;
+ u32 nr_maps, maplen;
+ u32 epoch;
+ struct ceph_osdmap *newmap = NULL, *oldmap;
+ int err;
+ struct ceph_fsid fsid;
+
+ dout("handle_map have %u\n", osdc->osdmap ? osdc->osdmap->epoch : 0);
+ p = msg->front.iov_base;
+ end = p + msg->front.iov_len;
+
+ /* verify fsid */
+ ceph_decode_need(&p, end, sizeof(fsid), bad);
+ ceph_decode_copy(&p, &fsid, sizeof(fsid));
+ if (ceph_fsid_compare(&fsid, &osdc->client->monc.monmap->fsid)) {
+ pr_err("got osdmap with wrong fsid, ignoring\n");
+ return;
+ }
+
+ down_write(&osdc->map_sem);
+
+ /* incremental maps */
+ ceph_decode_32_safe(&p, end, nr_maps, bad);
+ dout(" %d inc maps\n", nr_maps);
+ while (nr_maps > 0) {
+ ceph_decode_need(&p, end, 2*sizeof(u32), bad);
+ ceph_decode_32(&p, epoch);
+ ceph_decode_32(&p, maplen);
+ ceph_decode_need(&p, end, maplen, bad);
+ next = p + maplen;
+ if (osdc->osdmap && osdc->osdmap->epoch+1 == epoch) {
+ dout("applying incremental map %u len %d\n",
+ epoch, maplen);
+ newmap = osdmap_apply_incremental(&p, next,
+ osdc->osdmap,
+ osdc->client->msgr);
+ if (IS_ERR(newmap)) {
+ err = PTR_ERR(newmap);
+ goto bad;
+ }
+ if (newmap != osdc->osdmap) {
+ ceph_osdmap_destroy(osdc->osdmap);
+ osdc->osdmap = newmap;
+ }
+ } else {
+ dout("ignoring incremental map %u len %d\n",
+ epoch, maplen);
+ }
+ p = next;
+ nr_maps--;
+ }
+ if (newmap)
+ goto done;
+
+ /* full maps */
+ ceph_decode_32_safe(&p, end, nr_maps, bad);
+ dout(" %d full maps\n", nr_maps);
+ while (nr_maps) {
+ ceph_decode_need(&p, end, 2*sizeof(u32), bad);
+ ceph_decode_32(&p, epoch);
+ ceph_decode_32(&p, maplen);
+ ceph_decode_need(&p, end, maplen, bad);
+ if (nr_maps > 1) {
+ dout("skipping non-latest full map %u len %d\n",
+ epoch, maplen);
+ } else if (osdc->osdmap && osdc->osdmap->epoch >= epoch) {
+ dout("skipping full map %u len %d, "
+ "older than our %u\n", epoch, maplen,
+ osdc->osdmap->epoch);
+ } else {
+ dout("taking full map %u len %d\n", epoch, maplen);
+ newmap = osdmap_decode(&p, p+maplen);
+ if (IS_ERR(newmap)) {
+ err = PTR_ERR(newmap);
+ goto bad;
+ }
+ oldmap = osdc->osdmap;
+ osdc->osdmap = newmap;
+ if (oldmap)
+ ceph_osdmap_destroy(oldmap);
+ }
+ p += maplen;
+ nr_maps--;
+ }
+
+done:
+ downgrade_write(&osdc->map_sem);
+ ceph_monc_got_osdmap(&osdc->client->monc, osdc->osdmap->epoch);
+ if (newmap)
+ kick_requests(osdc, NULL);
+ up_read(&osdc->map_sem);
+ return;
+
+bad:
+ pr_err("osdc handle_map corrupt msg\n");
+ up_write(&osdc->map_sem);
+ return;
+}
+
+
+/*
+ * A read request prepares specific pages that data is to be read into.
+ * When a message is being read off the wire, we call prepare_pages to
+ * find those pages.
+ * 0 = success, -1 failure.
+ */
+static int prepare_pages(struct ceph_connection *con, struct ceph_msg *m,
+ int want)
+{
+ struct ceph_osd *osd = con->private;
+ struct ceph_osd_client *osdc;
+ struct ceph_osd_reply_head *rhead = m->front.iov_base;
+ struct ceph_osd_request *req;
+ u64 tid;
+ int ret = -1;
+ int type = le16_to_cpu(m->hdr.type);
+
+ if (!osd)
+ return -1;
+ osdc = osd->o_osdc;
+
+ dout("prepare_pages on msg %p want %d\n", m, want);
+ if (unlikely(type != CEPH_MSG_OSD_OPREPLY))
+ return -1; /* hmm! */
+
+ tid = le64_to_cpu(rhead->tid);
+ mutex_lock(&osdc->request_mutex);
+ req = __lookup_request(osdc, tid);
+ if (!req) {
+ dout("prepare_pages unknown tid %llu\n", tid);
+ goto out;
+ }
+ dout("prepare_pages tid %llu has %d pages, want %d\n",
+ tid, req->r_num_pages, want);
+ if (likely(req->r_num_pages >= want && !req->r_prepared_pages)) {
+ m->pages = req->r_pages;
+ m->nr_pages = req->r_num_pages;
+ req->r_reply = m; /* only for duration of read over socket */
+ ceph_msg_get(m);
+ req->r_prepared_pages = 1;
+ ret = 0; /* success */
+ }
+out:
+ mutex_unlock(&osdc->request_mutex);
+ return ret;
+}
+
+/*
+ * Register request, send initial attempt.
+ */
+int ceph_osdc_start_request(struct ceph_osd_client *osdc,
+ struct ceph_osd_request *req,
+ bool nofail)
+{
+ int rc;
+
+ req->r_request->pages = req->r_pages;
+ req->r_request->nr_pages = req->r_num_pages;
+
+ register_request(osdc, req);
+
+ down_read(&osdc->map_sem);
+ mutex_lock(&osdc->request_mutex);
+ rc = __send_request(osdc, req);
+ if (rc) {
+ if (nofail) {
+ dout("osdc_start_request failed send, marking %lld\n",
+ req->r_tid);
+ req->r_resend = true;
+ rc = 0;
+ } else {
+ __unregister_request(osdc, req);
+ }
+ }
+ mutex_unlock(&osdc->request_mutex);
+ up_read(&osdc->map_sem);
+ return rc;
+}
+
+/*
+ * wait for a request to complete
+ */
+int ceph_osdc_wait_request(struct ceph_osd_client *osdc,
+ struct ceph_osd_request *req)
+{
+ int rc;
+
+ rc = wait_for_completion_interruptible(&req->r_completion);
+ if (rc < 0) {
+ mutex_lock(&osdc->request_mutex);
+ __cancel_request(req);
+ mutex_unlock(&osdc->request_mutex);
+ dout("wait_request tid %llu timed out\n", req->r_tid);
+ return rc;
+ }
+
+ dout("wait_request tid %llu result %d\n", req->r_tid, req->r_result);
+ return req->r_result;
+}
+
+/*
+ * sync - wait for all in-flight requests to flush. avoid starvation.
+ */
+void ceph_osdc_sync(struct ceph_osd_client *osdc)
+{
+ struct ceph_osd_request *req;
+ u64 last_tid, next_tid = 0;
+
+ mutex_lock(&osdc->request_mutex);
+ last_tid = osdc->last_tid;
+ while (1) {
+ req = __lookup_request_ge(osdc, next_tid);
+ if (!req)
+ break;
+ if (req->r_tid > last_tid)
+ break;
+
+ next_tid = req->r_tid + 1;
+ if ((req->r_flags & CEPH_OSD_FLAG_WRITE) == 0)
+ continue;
+
+ ceph_osdc_get_request(req);
+ mutex_unlock(&osdc->request_mutex);
+ dout("sync waiting on tid %llu (last is %llu)\n",
+ req->r_tid, last_tid);
+ wait_for_completion(&req->r_safe_completion);
+ mutex_lock(&osdc->request_mutex);
+ ceph_osdc_put_request(req);
+ }
+ mutex_unlock(&osdc->request_mutex);
+ dout("sync done (thru tid %llu)\n", last_tid);
+}
+
+/*
+ * init, shutdown
+ */
+int ceph_osdc_init(struct ceph_osd_client *osdc, struct ceph_client *client)
+{
+ int err;
+
+ dout("init\n");
+ osdc->client = client;
+ osdc->osdmap = NULL;
+ init_rwsem(&osdc->map_sem);
+ init_completion(&osdc->map_waiters);
+ osdc->last_requested_map = 0;
+ mutex_init(&osdc->request_mutex);
+ osdc->timeout_tid = 0;
+ osdc->last_tid = 0;
+ osdc->osds = RB_ROOT;
+ osdc->requests = RB_ROOT;
+ osdc->num_requests = 0;
+ INIT_DELAYED_WORK(&osdc->timeout_work, handle_timeout);
+
+ osdc->req_mempool = mempool_create_kmalloc_pool(10,
+ sizeof(struct ceph_osd_request));
+ if (!osdc->req_mempool)
+ return -ENOMEM;
+
+ err = ceph_msgpool_init(&osdc->msgpool_op, 4096, 10, true);
+ if (err < 0)
+ return -ENOMEM;
+ err = ceph_msgpool_init(&osdc->msgpool_op_reply, 512, 0, false);
+ if (err < 0)
+ return -ENOMEM;
+
+ return 0;
+}
+
+void ceph_osdc_stop(struct ceph_osd_client *osdc)
+{
+ cancel_delayed_work_sync(&osdc->timeout_work);
+ if (osdc->osdmap) {
+ ceph_osdmap_destroy(osdc->osdmap);
+ osdc->osdmap = NULL;
+ }
+ mempool_destroy(osdc->req_mempool);
+ ceph_msgpool_destroy(&osdc->msgpool_op);
+ ceph_msgpool_destroy(&osdc->msgpool_op_reply);
+}
+
+/*
+ * Read some contiguous pages. If we cross a stripe boundary, shorten
+ * *plen. Return number of bytes read, or error.
+ */
+int ceph_osdc_readpages(struct ceph_osd_client *osdc,
+ struct ceph_vino vino, struct ceph_file_layout *layout,
+ u64 off, u64 *plen,
+ u32 truncate_seq, u64 truncate_size,
+ struct page **pages, int num_pages)
+{
+ struct ceph_osd_request *req;
+ int rc = 0;
+
+ dout("readpages on ino %llx.%llx on %llu~%llu\n", vino.ino,
+ vino.snap, off, *plen);
+ req = ceph_osdc_new_request(osdc, layout, vino, off, plen,
+ CEPH_OSD_OP_READ, CEPH_OSD_FLAG_READ,
+ NULL, 0, truncate_seq, truncate_size, NULL,
+ false, 1);
+ if (IS_ERR(req))
+ return PTR_ERR(req);
+
+ /* it may be a short read due to an object boundary */
+ req->r_pages = pages;
+ num_pages = calc_pages_for(off, *plen);
+ req->r_num_pages = num_pages;
+
+ dout("readpages final extent is %llu~%llu (%d pages)\n",
+ off, *plen, req->r_num_pages);
+
+ rc = ceph_osdc_start_request(osdc, req, false);
+ if (!rc)
+ rc = ceph_osdc_wait_request(osdc, req);
+
+ ceph_osdc_put_request(req);
+ dout("readpages result %d\n", rc);
+ return rc;
+}
+
+/*
+ * do a synchronous write on N pages
+ */
+int ceph_osdc_writepages(struct ceph_osd_client *osdc, struct ceph_vino vino,
+ struct ceph_file_layout *layout,
+ struct ceph_snap_context *snapc,
+ u64 off, u64 len,
+ u32 truncate_seq, u64 truncate_size,
+ struct timespec *mtime,
+ struct page **pages, int num_pages,
+ int flags, int do_sync, bool nofail)
+{
+ struct ceph_osd_request *req;
+ int rc = 0;
+
+ BUG_ON(vino.snap != CEPH_NOSNAP);
+ req = ceph_osdc_new_request(osdc, layout, vino, off, &len,
+ CEPH_OSD_OP_WRITE,
+ flags | CEPH_OSD_FLAG_ONDISK |
+ CEPH_OSD_FLAG_WRITE,
+ snapc, do_sync,
+ truncate_seq, truncate_size, mtime,
+ nofail, 1);
+ if (IS_ERR(req))
+ return PTR_ERR(req);
+
+ /* it may be a short write due to an object boundary */
+ req->r_pages = pages;
+ req->r_num_pages = calc_pages_for(off, len);
+ dout("writepages %llu~%llu (%d pages)\n", off, len,
+ req->r_num_pages);
+
+ rc = ceph_osdc_start_request(osdc, req, nofail);
+ if (!rc)
+ rc = ceph_osdc_wait_request(osdc, req);
+
+ ceph_osdc_put_request(req);
+ if (rc == 0)
+ rc = len;
+ dout("writepages result %d\n", rc);
+ return rc;
+}
+
+/*
+ * handle incoming message
+ */
+static void dispatch(struct ceph_connection *con, struct ceph_msg *msg)
+{
+ struct ceph_osd *osd = con->private;
+ struct ceph_osd_client *osdc = osd->o_osdc;
+ int type = le16_to_cpu(msg->hdr.type);
+
+ if (!osd)
+ return;
+
+ switch (type) {
+ case CEPH_MSG_OSD_MAP:
+ ceph_osdc_handle_map(osdc, msg);
+ break;
+ case CEPH_MSG_OSD_OPREPLY:
+ handle_reply(osdc, msg);
+ break;
+
+ default:
+ pr_err("received unknown message type %d %s\n", type,
+ ceph_msg_type_name(type));
+ }
+ ceph_msg_put(msg);
+}
+
+static struct ceph_msg *alloc_msg(struct ceph_connection *con,
+ struct ceph_msg_header *hdr)
+{
+ struct ceph_osd *osd = con->private;
+ struct ceph_osd_client *osdc = osd->o_osdc;
+ int type = le16_to_cpu(hdr->type);
+
+ switch (type) {
+ case CEPH_MSG_OSD_OPREPLY:
+ return ceph_msgpool_get(&osdc->msgpool_op_reply);
+ }
+ return ceph_alloc_msg(con, hdr);
+}
+
+/*
+ * Wrappers to refcount containing ceph_osd struct
+ */
+static struct ceph_connection *get_osd_con(struct ceph_connection *con)
+{
+ struct ceph_osd *osd = con->private;
+ if (get_osd(osd))
+ return con;
+ return NULL;
+}
+
+static void put_osd_con(struct ceph_connection *con)
+{
+ struct ceph_osd *osd = con->private;
+ put_osd(osd);
+}
+
+const static struct ceph_connection_operations osd_con_ops = {
+ .get = get_osd_con,
+ .put = put_osd_con,
+ .dispatch = dispatch,
+ .alloc_msg = alloc_msg,
+ .peer_reset = osd_reset,
+ .alloc_middle = ceph_alloc_middle,
+ .prepare_pages = prepare_pages,
+};