diff options
Diffstat (limited to 'fs/ceph/mdsmap.c')
| -rw-r--r-- | fs/ceph/mdsmap.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/fs/ceph/mdsmap.c b/fs/ceph/mdsmap.c new file mode 100644 index 000000000000..c4c498e6dfef --- /dev/null +++ b/fs/ceph/mdsmap.c @@ -0,0 +1,174 @@ +#include "ceph_debug.h" + +#include <linux/bug.h> +#include <linux/err.h> +#include <linux/random.h> +#include <linux/slab.h> +#include <linux/types.h> + +#include "mdsmap.h" +#include "messenger.h" +#include "decode.h" + +#include "super.h" + + +/* + * choose a random mds that is "up" (i.e. has a state > 0), or -1. + */ +int ceph_mdsmap_get_random_mds(struct ceph_mdsmap *m) +{ + int n = 0; + int i; + char r; + + /* count */ + for (i = 0; i < m->m_max_mds; i++) + if (m->m_info[i].state > 0) + n++; + if (n == 0) + return -1; + + /* pick */ + get_random_bytes(&r, 1); + n = r % n; + i = 0; + for (i = 0; n > 0; i++, n--) + while (m->m_info[i].state <= 0) + i++; + + return i; +} + +/* + * Decode an MDS map + * + * Ignore any fields we don't care about (there are quite a few of + * them). + */ +struct ceph_mdsmap *ceph_mdsmap_decode(void **p, void *end) +{ + struct ceph_mdsmap *m; + const void *start = *p; + int i, j, n; + int err = -EINVAL; + u16 version; + + m = kzalloc(sizeof(*m), GFP_NOFS); + if (m == NULL) + return ERR_PTR(-ENOMEM); + + ceph_decode_16_safe(p, end, version, bad); + + ceph_decode_need(p, end, 8*sizeof(u32) + sizeof(u64), bad); + m->m_epoch = ceph_decode_32(p); + m->m_client_epoch = ceph_decode_32(p); + m->m_last_failure = ceph_decode_32(p); + m->m_root = ceph_decode_32(p); + m->m_session_timeout = ceph_decode_32(p); + m->m_session_autoclose = ceph_decode_32(p); + m->m_max_file_size = ceph_decode_64(p); + m->m_max_mds = ceph_decode_32(p); + + m->m_info = kcalloc(m->m_max_mds, sizeof(*m->m_info), GFP_NOFS); + if (m->m_info == NULL) + goto badmem; + + /* pick out active nodes from mds_info (state > 0) */ + n = ceph_decode_32(p); + for (i = 0; i < n; i++) { + u64 global_id; + u32 namelen; + s32 mds, inc, state; + u64 state_seq; + u8 infoversion; + struct ceph_entity_addr addr; + u32 num_export_targets; + void *pexport_targets = NULL; + + ceph_decode_need(p, end, sizeof(u64)*2 + 1 + sizeof(u32), bad); + global_id = ceph_decode_64(p); + infoversion = ceph_decode_8(p); + *p += sizeof(u64); + namelen = ceph_decode_32(p); /* skip mds name */ + *p += namelen; + + ceph_decode_need(p, end, + 4*sizeof(u32) + sizeof(u64) + + sizeof(addr) + sizeof(struct ceph_timespec), + bad); + mds = ceph_decode_32(p); + inc = ceph_decode_32(p); + state = ceph_decode_32(p); + state_seq = ceph_decode_64(p); + ceph_decode_copy(p, &addr, sizeof(addr)); + ceph_decode_addr(&addr); + *p += sizeof(struct ceph_timespec); + *p += sizeof(u32); + ceph_decode_32_safe(p, end, namelen, bad); + *p += namelen; + if (infoversion >= 2) { + ceph_decode_32_safe(p, end, num_export_targets, bad); + pexport_targets = *p; + *p += num_export_targets * sizeof(u32); + } else { + num_export_targets = 0; + } + + dout("mdsmap_decode %d/%d %lld mds%d.%d %s %s\n", + i+1, n, global_id, mds, inc, pr_addr(&addr.in_addr), + ceph_mds_state_name(state)); + if (mds >= 0 && mds < m->m_max_mds && state > 0) { + m->m_info[mds].global_id = global_id; + m->m_info[mds].state = state; + m->m_info[mds].addr = addr; + m->m_info[mds].num_export_targets = num_export_targets; + if (num_export_targets) { + m->m_info[mds].export_targets = + kcalloc(num_export_targets, sizeof(u32), + GFP_NOFS); + for (j = 0; j < num_export_targets; j++) + m->m_info[mds].export_targets[j] = + ceph_decode_32(&pexport_targets); + } else { + m->m_info[mds].export_targets = NULL; + } + } + } + + /* pg_pools */ + ceph_decode_32_safe(p, end, n, bad); + m->m_num_data_pg_pools = n; + m->m_data_pg_pools = kcalloc(n, sizeof(u32), GFP_NOFS); + if (!m->m_data_pg_pools) + goto badmem; + ceph_decode_need(p, end, sizeof(u32)*(n+1), bad); + for (i = 0; i < n; i++) + m->m_data_pg_pools[i] = ceph_decode_32(p); + m->m_cas_pg_pool = ceph_decode_32(p); + + /* ok, we don't care about the rest. */ + dout("mdsmap_decode success epoch %u\n", m->m_epoch); + return m; + +badmem: + err = -ENOMEM; +bad: + pr_err("corrupt mdsmap\n"); + print_hex_dump(KERN_DEBUG, "mdsmap: ", + DUMP_PREFIX_OFFSET, 16, 1, + start, end - start, true); + ceph_mdsmap_destroy(m); + return ERR_PTR(-EINVAL); +} + +void ceph_mdsmap_destroy(struct ceph_mdsmap *m) +{ + int i; + + for (i = 0; i < m->m_max_mds; i++) + kfree(m->m_info[i].export_targets); + kfree(m->m_info); + kfree(m->m_data_pg_pools); + kfree(m); +} |