diff options
| -rw-r--r-- | fs/ceph/mds_client.c | 71 |
1 files changed, 70 insertions, 1 deletions
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c index 5edf206354b2..5474feb77743 100644 --- a/fs/ceph/mds_client.c +++ b/fs/ceph/mds_client.c @@ -7,6 +7,7 @@ #include <linux/sched.h> #include <linux/debugfs.h> #include <linux/seq_file.h> +#include <linux/utsname.h> #include "super.h" #include "mds_client.h" @@ -812,6 +813,74 @@ static struct ceph_msg *create_session_msg(u32 op, u64 seq) h = msg->front.iov_base; h->op = cpu_to_le32(op); h->seq = cpu_to_le64(seq); + + return msg; +} + +/* + * session message, specialization for CEPH_SESSION_REQUEST_OPEN + * to include additional client metadata fields. + */ +static struct ceph_msg *create_session_open_msg(struct ceph_mds_client *mdsc, u64 seq) +{ + struct ceph_msg *msg; + struct ceph_mds_session_head *h; + int i = -1; + int metadata_bytes = 0; + int metadata_key_count = 0; + struct ceph_options *opt = mdsc->fsc->client->options; + void *p; + + const char* metadata[3][2] = { + {"hostname", utsname()->nodename}, + {"entity_id", opt->name ? opt->name : ""}, + {NULL, NULL} + }; + + /* Calculate serialized length of metadata */ + metadata_bytes = 4; /* map length */ + for (i = 0; metadata[i][0] != NULL; ++i) { + metadata_bytes += 8 + strlen(metadata[i][0]) + + strlen(metadata[i][1]); + metadata_key_count++; + } + + /* Allocate the message */ + msg = ceph_msg_new(CEPH_MSG_CLIENT_SESSION, sizeof(*h) + metadata_bytes, + GFP_NOFS, false); + if (!msg) { + pr_err("create_session_msg ENOMEM creating msg\n"); + return NULL; + } + h = msg->front.iov_base; + h->op = cpu_to_le32(CEPH_SESSION_REQUEST_OPEN); + h->seq = cpu_to_le64(seq); + + /* + * Serialize client metadata into waiting buffer space, using + * the format that userspace expects for map<string, string> + */ + msg->hdr.version = 2; /* ClientSession messages with metadata are v2 */ + + /* The write pointer, following the session_head structure */ + p = msg->front.iov_base + sizeof(*h); + + /* Number of entries in the map */ + ceph_encode_32(&p, metadata_key_count); + + /* Two length-prefixed strings for each entry in the map */ + for (i = 0; metadata[i][0] != NULL; ++i) { + size_t const key_len = strlen(metadata[i][0]); + size_t const val_len = strlen(metadata[i][1]); + + ceph_encode_32(&p, key_len); + memcpy(p, metadata[i][0], key_len); + p += key_len; + ceph_encode_32(&p, val_len); + memcpy(p, metadata[i][1], val_len); + p += val_len; + } + return msg; } @@ -835,7 +904,7 @@ static int __open_session(struct ceph_mds_client *mdsc, session->s_renew_requested = jiffies; /* send connect message */ - msg = create_session_msg(CEPH_SESSION_REQUEST_OPEN, session->s_seq); + msg = create_session_open_msg(mdsc, session->s_seq); if (!msg) return -ENOMEM; ceph_con_send(&session->s_con, msg); |