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-rw-r--r--fs/dlm/dir.c423
1 files changed, 423 insertions, 0 deletions
diff --git a/fs/dlm/dir.c b/fs/dlm/dir.c
new file mode 100644
index 00000000000..46754553fdc
--- /dev/null
+++ b/fs/dlm/dir.c
@@ -0,0 +1,423 @@
+/******************************************************************************
+*******************************************************************************
+**
+** 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"
+
+
+static void put_free_de(struct dlm_ls *ls, struct dlm_direntry *de)
+{
+ spin_lock(&ls->ls_recover_list_lock);
+ list_add(&de->list, &ls->ls_recover_list);
+ spin_unlock(&ls->ls_recover_list_lock);
+}
+
+static struct dlm_direntry *get_free_de(struct dlm_ls *ls, int len)
+{
+ int found = 0;
+ struct dlm_direntry *de;
+
+ spin_lock(&ls->ls_recover_list_lock);
+ list_for_each_entry(de, &ls->ls_recover_list, list) {
+ if (de->length == len) {
+ list_del(&de->list);
+ de->master_nodeid = 0;
+ memset(de->name, 0, len);
+ found = 1;
+ break;
+ }
+ }
+ spin_unlock(&ls->ls_recover_list_lock);
+
+ if (!found)
+ de = allocate_direntry(ls, len);
+ return de;
+}
+
+void dlm_clear_free_entries(struct dlm_ls *ls)
+{
+ struct dlm_direntry *de;
+
+ spin_lock(&ls->ls_recover_list_lock);
+ while (!list_empty(&ls->ls_recover_list)) {
+ de = list_entry(ls->ls_recover_list.next, struct dlm_direntry,
+ list);
+ list_del(&de->list);
+ free_direntry(de);
+ }
+ spin_unlock(&ls->ls_recover_list_lock);
+}
+
+/*
+ * 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)
+{
+ struct list_head *tmp;
+ struct dlm_member *memb = NULL;
+ uint32_t node, n = 0;
+ int nodeid;
+
+ if (ls->ls_num_nodes == 1) {
+ nodeid = dlm_our_nodeid();
+ goto out;
+ }
+
+ if (ls->ls_node_array) {
+ node = (hash >> 16) % ls->ls_total_weight;
+ nodeid = ls->ls_node_array[node];
+ goto out;
+ }
+
+ /* make_member_array() failed to kmalloc ls_node_array... */
+
+ node = (hash >> 16) % ls->ls_num_nodes;
+
+ list_for_each(tmp, &ls->ls_nodes) {
+ if (n++ != node)
+ continue;
+ memb = list_entry(tmp, struct dlm_member, list);
+ break;
+ }
+
+ DLM_ASSERT(memb , printk("num_nodes=%u n=%u node=%u\n",
+ ls->ls_num_nodes, n, node););
+ nodeid = memb->nodeid;
+ out:
+ return nodeid;
+}
+
+int dlm_dir_nodeid(struct dlm_rsb *r)
+{
+ return dlm_hash2nodeid(r->res_ls, r->res_hash);
+}
+
+static inline uint32_t dir_hash(struct dlm_ls *ls, char *name, int len)
+{
+ uint32_t val;
+
+ val = jhash(name, len, 0);
+ val &= (ls->ls_dirtbl_size - 1);
+
+ return val;
+}
+
+static void add_entry_to_hash(struct dlm_ls *ls, struct dlm_direntry *de)
+{
+ uint32_t bucket;
+
+ bucket = dir_hash(ls, de->name, de->length);
+ list_add_tail(&de->list, &ls->ls_dirtbl[bucket].list);
+}
+
+static struct dlm_direntry *search_bucket(struct dlm_ls *ls, char *name,
+ int namelen, uint32_t bucket)
+{
+ struct dlm_direntry *de;
+
+ list_for_each_entry(de, &ls->ls_dirtbl[bucket].list, list) {
+ if (de->length == namelen && !memcmp(name, de->name, namelen))
+ goto out;
+ }
+ de = NULL;
+ out:
+ return de;
+}
+
+void dlm_dir_remove_entry(struct dlm_ls *ls, int nodeid, char *name, int namelen)
+{
+ struct dlm_direntry *de;
+ uint32_t bucket;
+
+ bucket = dir_hash(ls, name, namelen);
+
+ write_lock(&ls->ls_dirtbl[bucket].lock);
+
+ de = search_bucket(ls, name, namelen, bucket);
+
+ if (!de) {
+ log_error(ls, "remove fr %u none", nodeid);
+ goto out;
+ }
+
+ if (de->master_nodeid != nodeid) {
+ log_error(ls, "remove fr %u ID %u", nodeid, de->master_nodeid);
+ goto out;
+ }
+
+ list_del(&de->list);
+ free_direntry(de);
+ out:
+ write_unlock(&ls->ls_dirtbl[bucket].lock);
+}
+
+void dlm_dir_clear(struct dlm_ls *ls)
+{
+ struct list_head *head;
+ struct dlm_direntry *de;
+ int i;
+
+ DLM_ASSERT(list_empty(&ls->ls_recover_list), );
+
+ for (i = 0; i < ls->ls_dirtbl_size; i++) {
+ write_lock(&ls->ls_dirtbl[i].lock);
+ head = &ls->ls_dirtbl[i].list;
+ while (!list_empty(head)) {
+ de = list_entry(head->next, struct dlm_direntry, list);
+ list_del(&de->list);
+ put_free_de(ls, de);
+ }
+ write_unlock(&ls->ls_dirtbl[i].lock);
+ }
+}
+
+int dlm_recover_directory(struct dlm_ls *ls)
+{
+ struct dlm_member *memb;
+ struct dlm_direntry *de;
+ char *b, *last_name = NULL;
+ int error = -ENOMEM, last_len, count = 0;
+ uint16_t namelen;
+
+ log_debug(ls, "dlm_recover_directory");
+
+ if (dlm_no_directory(ls))
+ goto out_status;
+
+ dlm_dir_clear(ls);
+
+ last_name = kmalloc(DLM_RESNAME_MAXLEN, GFP_KERNEL);
+ if (!last_name)
+ goto out;
+
+ list_for_each_entry(memb, &ls->ls_nodes, list) {
+ memset(last_name, 0, DLM_RESNAME_MAXLEN);
+ last_len = 0;
+
+ for (;;) {
+ 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;
+
+ schedule();
+
+ /*
+ * pick namelen/name pairs out of received buffer
+ */
+
+ b = ls->ls_recover_buf + sizeof(struct dlm_rcom);
+
+ for (;;) {
+ memcpy(&namelen, b, sizeof(uint16_t));
+ namelen = be16_to_cpu(namelen);
+ b += sizeof(uint16_t);
+
+ /* 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;
+
+ error = -ENOMEM;
+ de = get_free_de(ls, namelen);
+ if (!de)
+ goto out_free;
+
+ de->master_nodeid = memb->nodeid;
+ de->length = namelen;
+ last_len = namelen;
+ memcpy(de->name, b, namelen);
+ memcpy(last_name, b, namelen);
+ b += namelen;
+
+ add_entry_to_hash(ls, de);
+ count++;
+ }
+ }
+ done:
+ ;
+ }
+
+ out_status:
+ error = 0;
+ dlm_set_recover_status(ls, DLM_RS_DIR);
+ log_debug(ls, "dlm_recover_directory %d entries", count);
+ out_free:
+ kfree(last_name);
+ out:
+ dlm_clear_free_entries(ls);
+ return error;
+}
+
+static int get_entry(struct dlm_ls *ls, int nodeid, char *name,
+ int namelen, int *r_nodeid)
+{
+ struct dlm_direntry *de, *tmp;
+ uint32_t bucket;
+
+ bucket = dir_hash(ls, name, namelen);
+
+ write_lock(&ls->ls_dirtbl[bucket].lock);
+ de = search_bucket(ls, name, namelen, bucket);
+ if (de) {
+ *r_nodeid = de->master_nodeid;
+ write_unlock(&ls->ls_dirtbl[bucket].lock);
+ if (*r_nodeid == nodeid)
+ return -EEXIST;
+ return 0;
+ }
+
+ write_unlock(&ls->ls_dirtbl[bucket].lock);
+
+ de = allocate_direntry(ls, namelen);
+ if (!de)
+ return -ENOMEM;
+
+ de->master_nodeid = nodeid;
+ de->length = namelen;
+ memcpy(de->name, name, namelen);
+
+ write_lock(&ls->ls_dirtbl[bucket].lock);
+ tmp = search_bucket(ls, name, namelen, bucket);
+ if (tmp) {
+ free_direntry(de);
+ de = tmp;
+ } else {
+ list_add_tail(&de->list, &ls->ls_dirtbl[bucket].list);
+ }
+ *r_nodeid = de->master_nodeid;
+ write_unlock(&ls->ls_dirtbl[bucket].lock);
+ return 0;
+}
+
+int dlm_dir_lookup(struct dlm_ls *ls, int nodeid, char *name, int namelen,
+ int *r_nodeid)
+{
+ return get_entry(ls, nodeid, name, namelen, r_nodeid);
+}
+
+/* Copy the names of master rsb's into the buffer provided.
+ Only select names whose dir node is the given nodeid. */
+
+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 *start_r = NULL, *r = NULL;
+ int offset = 0, start_namelen, error, dir_nodeid;
+ char *start_name;
+ uint16_t be_namelen;
+
+ /*
+ * Find the rsb where we left off (or start again)
+ */
+
+ start_namelen = inlen;
+ start_name = inbuf;
+
+ if (start_namelen > 1) {
+ /*
+ * We could also use a find_rsb_root() function here that
+ * searched the ls_root_list.
+ */
+ error = dlm_find_rsb(ls, start_name, start_namelen, R_MASTER,
+ &start_r);
+ DLM_ASSERT(!error && start_r,
+ printk("error %d\n", error););
+ DLM_ASSERT(!list_empty(&start_r->res_root_list),
+ dlm_print_rsb(start_r););
+ dlm_put_rsb(start_r);
+ }
+
+ /*
+ * Send rsb names for rsb's we're master of and whose directory node
+ * matches the requesting node.
+ */
+
+ down_read(&ls->ls_root_sem);
+ if (start_r)
+ list = start_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 = 0;
+ memcpy(outbuf + offset, &be_namelen, sizeof(uint16_t));
+ offset += sizeof(uint16_t);
+ goto out;
+ }
+
+ be_namelen = cpu_to_be16(r->res_length);
+ memcpy(outbuf + offset, &be_namelen, sizeof(uint16_t));
+ offset += sizeof(uint16_t);
+ memcpy(outbuf + offset, r->res_name, r->res_length);
+ offset += r->res_length;
+ }
+
+ /*
+ * 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 = 0xFFFF;
+ memcpy(outbuf + offset, &be_namelen, sizeof(uint16_t));
+ offset += sizeof(uint16_t);
+ }
+
+ out:
+ up_read(&ls->ls_root_sem);
+}
+
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