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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /fs/dlm/dir.c
Initial import
Diffstat (limited to 'fs/dlm/dir.c')
-rw-r--r--fs/dlm/dir.c308
1 files changed, 308 insertions, 0 deletions
diff --git a/fs/dlm/dir.c b/fs/dlm/dir.c
new file mode 100644
index 000000000..d975851a7
--- /dev/null
+++ b/fs/dlm/dir.c
@@ -0,0 +1,308 @@
+/******************************************************************************
+*******************************************************************************
+**
+** Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved.
+** Copyright (C) 2004-2005 Red Hat, Inc. All rights reserved.
+**
+** This copyrighted material is made available to anyone wishing to use,
+** modify, copy, or redistribute it subject to the terms and conditions
+** of the GNU General Public License v.2.
+**
+*******************************************************************************
+******************************************************************************/
+
+#include "dlm_internal.h"
+#include "lockspace.h"
+#include "member.h"
+#include "lowcomms.h"
+#include "rcom.h"
+#include "config.h"
+#include "memory.h"
+#include "recover.h"
+#include "util.h"
+#include "lock.h"
+#include "dir.h"
+
+/*
+ * We use the upper 16 bits of the hash value to select the directory node.
+ * Low bits are used for distribution of rsb's among hash buckets on each node.
+ *
+ * To give the exact range wanted (0 to num_nodes-1), we apply a modulus of
+ * num_nodes to the hash value. This value in the desired range is used as an
+ * offset into the sorted list of nodeid's to give the particular nodeid.
+ */
+
+int dlm_hash2nodeid(struct dlm_ls *ls, uint32_t hash)
+{
+ uint32_t node;
+
+ if (ls->ls_num_nodes == 1)
+ return dlm_our_nodeid();
+ else {
+ node = (hash >> 16) % ls->ls_total_weight;
+ return ls->ls_node_array[node];
+ }
+}
+
+int dlm_dir_nodeid(struct dlm_rsb *r)
+{
+ return r->res_dir_nodeid;
+}
+
+void dlm_recover_dir_nodeid(struct dlm_ls *ls)
+{
+ struct dlm_rsb *r;
+
+ down_read(&ls->ls_root_sem);
+ list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
+ r->res_dir_nodeid = dlm_hash2nodeid(ls, r->res_hash);
+ }
+ up_read(&ls->ls_root_sem);
+}
+
+int dlm_recover_directory(struct dlm_ls *ls)
+{
+ struct dlm_member *memb;
+ char *b, *last_name = NULL;
+ int error = -ENOMEM, last_len, nodeid, result;
+ uint16_t namelen;
+ unsigned int count = 0, count_match = 0, count_bad = 0, count_add = 0;
+
+ log_rinfo(ls, "dlm_recover_directory");
+
+ if (dlm_no_directory(ls))
+ goto out_status;
+
+ last_name = kmalloc(DLM_RESNAME_MAXLEN, GFP_NOFS);
+ if (!last_name)
+ goto out;
+
+ list_for_each_entry(memb, &ls->ls_nodes, list) {
+ if (memb->nodeid == dlm_our_nodeid())
+ continue;
+
+ memset(last_name, 0, DLM_RESNAME_MAXLEN);
+ last_len = 0;
+
+ for (;;) {
+ int left;
+ error = dlm_recovery_stopped(ls);
+ if (error)
+ goto out_free;
+
+ error = dlm_rcom_names(ls, memb->nodeid,
+ last_name, last_len);
+ if (error)
+ goto out_free;
+
+ cond_resched();
+
+ /*
+ * pick namelen/name pairs out of received buffer
+ */
+
+ b = ls->ls_recover_buf->rc_buf;
+ left = ls->ls_recover_buf->rc_header.h_length;
+ left -= sizeof(struct dlm_rcom);
+
+ for (;;) {
+ __be16 v;
+
+ error = -EINVAL;
+ if (left < sizeof(__be16))
+ goto out_free;
+
+ memcpy(&v, b, sizeof(__be16));
+ namelen = be16_to_cpu(v);
+ b += sizeof(__be16);
+ left -= sizeof(__be16);
+
+ /* namelen of 0xFFFFF marks end of names for
+ this node; namelen of 0 marks end of the
+ buffer */
+
+ if (namelen == 0xFFFF)
+ goto done;
+ if (!namelen)
+ break;
+
+ if (namelen > left)
+ goto out_free;
+
+ if (namelen > DLM_RESNAME_MAXLEN)
+ goto out_free;
+
+ error = dlm_master_lookup(ls, memb->nodeid,
+ b, namelen,
+ DLM_LU_RECOVER_DIR,
+ &nodeid, &result);
+ if (error) {
+ log_error(ls, "recover_dir lookup %d",
+ error);
+ goto out_free;
+ }
+
+ /* The name was found in rsbtbl, but the
+ * master nodeid is different from
+ * memb->nodeid which says it is the master.
+ * This should not happen. */
+
+ if (result == DLM_LU_MATCH &&
+ nodeid != memb->nodeid) {
+ count_bad++;
+ log_error(ls, "recover_dir lookup %d "
+ "nodeid %d memb %d bad %u",
+ result, nodeid, memb->nodeid,
+ count_bad);
+ print_hex_dump_bytes("dlm_recover_dir ",
+ DUMP_PREFIX_NONE,
+ b, namelen);
+ }
+
+ /* The name was found in rsbtbl, and the
+ * master nodeid matches memb->nodeid. */
+
+ if (result == DLM_LU_MATCH &&
+ nodeid == memb->nodeid) {
+ count_match++;
+ }
+
+ /* The name was not found in rsbtbl and was
+ * added with memb->nodeid as the master. */
+
+ if (result == DLM_LU_ADD) {
+ count_add++;
+ }
+
+ last_len = namelen;
+ memcpy(last_name, b, namelen);
+ b += namelen;
+ left -= namelen;
+ count++;
+ }
+ }
+ done:
+ ;
+ }
+
+ out_status:
+ error = 0;
+ dlm_set_recover_status(ls, DLM_RS_DIR);
+
+ log_rinfo(ls, "dlm_recover_directory %u in %u new",
+ count, count_add);
+ out_free:
+ kfree(last_name);
+ out:
+ return error;
+}
+
+static struct dlm_rsb *find_rsb_root(struct dlm_ls *ls, char *name, int len)
+{
+ struct dlm_rsb *r;
+ uint32_t hash, bucket;
+ int rv;
+
+ hash = jhash(name, len, 0);
+ bucket = hash & (ls->ls_rsbtbl_size - 1);
+
+ spin_lock(&ls->ls_rsbtbl[bucket].lock);
+ rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[bucket].keep, name, len, &r);
+ if (rv)
+ rv = dlm_search_rsb_tree(&ls->ls_rsbtbl[bucket].toss,
+ name, len, &r);
+ spin_unlock(&ls->ls_rsbtbl[bucket].lock);
+
+ if (!rv)
+ return r;
+
+ down_read(&ls->ls_root_sem);
+ list_for_each_entry(r, &ls->ls_root_list, res_root_list) {
+ if (len == r->res_length && !memcmp(name, r->res_name, len)) {
+ up_read(&ls->ls_root_sem);
+ log_debug(ls, "find_rsb_root revert to root_list %s",
+ r->res_name);
+ return r;
+ }
+ }
+ up_read(&ls->ls_root_sem);
+ return NULL;
+}
+
+/* Find the rsb where we left off (or start again), then send rsb names
+ for rsb's we're master of and whose directory node matches the requesting
+ node. inbuf is the rsb name last sent, inlen is the name's length */
+
+void dlm_copy_master_names(struct dlm_ls *ls, char *inbuf, int inlen,
+ char *outbuf, int outlen, int nodeid)
+{
+ struct list_head *list;
+ struct dlm_rsb *r;
+ int offset = 0, dir_nodeid;
+ __be16 be_namelen;
+
+ down_read(&ls->ls_root_sem);
+
+ if (inlen > 1) {
+ r = find_rsb_root(ls, inbuf, inlen);
+ if (!r) {
+ inbuf[inlen - 1] = '\0';
+ log_error(ls, "copy_master_names from %d start %d %s",
+ nodeid, inlen, inbuf);
+ goto out;
+ }
+ list = r->res_root_list.next;
+ } else {
+ list = ls->ls_root_list.next;
+ }
+
+ for (offset = 0; list != &ls->ls_root_list; list = list->next) {
+ r = list_entry(list, struct dlm_rsb, res_root_list);
+ if (r->res_nodeid)
+ continue;
+
+ dir_nodeid = dlm_dir_nodeid(r);
+ if (dir_nodeid != nodeid)
+ continue;
+
+ /*
+ * The block ends when we can't fit the following in the
+ * remaining buffer space:
+ * namelen (uint16_t) +
+ * name (r->res_length) +
+ * end-of-block record 0x0000 (uint16_t)
+ */
+
+ if (offset + sizeof(uint16_t)*2 + r->res_length > outlen) {
+ /* Write end-of-block record */
+ be_namelen = cpu_to_be16(0);
+ memcpy(outbuf + offset, &be_namelen, sizeof(__be16));
+ offset += sizeof(__be16);
+ ls->ls_recover_dir_sent_msg++;
+ goto out;
+ }
+
+ be_namelen = cpu_to_be16(r->res_length);
+ memcpy(outbuf + offset, &be_namelen, sizeof(__be16));
+ offset += sizeof(__be16);
+ memcpy(outbuf + offset, r->res_name, r->res_length);
+ offset += r->res_length;
+ ls->ls_recover_dir_sent_res++;
+ }
+
+ /*
+ * If we've reached the end of the list (and there's room) write a
+ * terminating record.
+ */
+
+ if ((list == &ls->ls_root_list) &&
+ (offset + sizeof(uint16_t) <= outlen)) {
+ be_namelen = cpu_to_be16(0xFFFF);
+ memcpy(outbuf + offset, &be_namelen, sizeof(__be16));
+ offset += sizeof(__be16);
+ ls->ls_recover_dir_sent_msg++;
+ }
+ out:
+ up_read(&ls->ls_root_sem);
+}
+