1 files changed, 423 insertions, 0 deletions

diff --git a/fs/dlm/dir.c b/fs/dlm/dir.c
new file mode 100644
index 000000000000..0f1dde54bcd2
--- /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 = FALSE;
+        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 = TRUE;
+                        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);
+}
+