v4.19.13 snapshot.
diff --git a/fs/afs/volume.c b/fs/afs/volume.c
new file mode 100644
index 0000000..3037bd0
--- /dev/null
+++ b/fs/afs/volume.c
@@ -0,0 +1,368 @@
+/* AFS volume management
+ *
+ * Copyright (C) 2002, 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include "internal.h"
+
+unsigned __read_mostly afs_volume_gc_delay = 10;
+unsigned __read_mostly afs_volume_record_life = 60 * 60;
+
+static const char *const afs_voltypes[] = { "R/W", "R/O", "BAK" };
+
+/*
+ * Allocate a volume record and load it up from a vldb record.
+ */
+static struct afs_volume *afs_alloc_volume(struct afs_mount_params *params,
+ struct afs_vldb_entry *vldb,
+ unsigned long type_mask)
+{
+ struct afs_server_list *slist;
+ struct afs_volume *volume;
+ int ret = -ENOMEM, nr_servers = 0, i;
+
+ for (i = 0; i < vldb->nr_servers; i++)
+ if (vldb->fs_mask[i] & type_mask)
+ nr_servers++;
+
+ volume = kzalloc(sizeof(struct afs_volume), GFP_KERNEL);
+ if (!volume)
+ goto error_0;
+
+ volume->vid = vldb->vid[params->type];
+ volume->update_at = ktime_get_real_seconds() + afs_volume_record_life;
+ volume->cell = afs_get_cell(params->cell);
+ volume->type = params->type;
+ volume->type_force = params->force;
+ volume->name_len = vldb->name_len;
+
+ atomic_set(&volume->usage, 1);
+ INIT_LIST_HEAD(&volume->proc_link);
+ rwlock_init(&volume->servers_lock);
+ memcpy(volume->name, vldb->name, vldb->name_len + 1);
+
+ slist = afs_alloc_server_list(params->cell, params->key, vldb, type_mask);
+ if (IS_ERR(slist)) {
+ ret = PTR_ERR(slist);
+ goto error_1;
+ }
+
+ refcount_set(&slist->usage, 1);
+ volume->servers = slist;
+ return volume;
+
+error_1:
+ afs_put_cell(params->net, volume->cell);
+ kfree(volume);
+error_0:
+ return ERR_PTR(ret);
+}
+
+/*
+ * Look up a VLDB record for a volume.
+ */
+static struct afs_vldb_entry *afs_vl_lookup_vldb(struct afs_cell *cell,
+ struct key *key,
+ const char *volname,
+ size_t volnamesz)
+{
+ struct afs_addr_cursor ac;
+ struct afs_vldb_entry *vldb;
+ int ret;
+
+ ret = afs_set_vl_cursor(&ac, cell);
+ if (ret < 0)
+ return ERR_PTR(ret);
+
+ while (afs_iterate_addresses(&ac)) {
+ if (!test_bit(ac.index, &ac.alist->probed)) {
+ ret = afs_vl_get_capabilities(cell->net, &ac, key);
+ switch (ret) {
+ case VL_SERVICE:
+ clear_bit(ac.index, &ac.alist->yfs);
+ set_bit(ac.index, &ac.alist->probed);
+ ac.addr->srx_service = ret;
+ break;
+ case YFS_VL_SERVICE:
+ set_bit(ac.index, &ac.alist->yfs);
+ set_bit(ac.index, &ac.alist->probed);
+ ac.addr->srx_service = ret;
+ break;
+ }
+ }
+
+ vldb = afs_vl_get_entry_by_name_u(cell->net, &ac, key,
+ volname, volnamesz);
+ switch (ac.error) {
+ case 0:
+ afs_end_cursor(&ac);
+ return vldb;
+ case -ECONNABORTED:
+ ac.error = afs_abort_to_error(ac.abort_code);
+ goto error;
+ case -ENOMEM:
+ case -ENONET:
+ goto error;
+ case -ENETUNREACH:
+ case -EHOSTUNREACH:
+ case -ECONNREFUSED:
+ break;
+ default:
+ ac.error = -EIO;
+ goto error;
+ }
+ }
+
+error:
+ return ERR_PTR(afs_end_cursor(&ac));
+}
+
+/*
+ * Look up a volume in the VL server and create a candidate volume record for
+ * it.
+ *
+ * The volume name can be one of the following:
+ * "%[cell:]volume[.]" R/W volume
+ * "#[cell:]volume[.]" R/O or R/W volume (rwparent=0),
+ * or R/W (rwparent=1) volume
+ * "%[cell:]volume.readonly" R/O volume
+ * "#[cell:]volume.readonly" R/O volume
+ * "%[cell:]volume.backup" Backup volume
+ * "#[cell:]volume.backup" Backup volume
+ *
+ * The cell name is optional, and defaults to the current cell.
+ *
+ * See "The Rules of Mount Point Traversal" in Chapter 5 of the AFS SysAdmin
+ * Guide
+ * - Rule 1: Explicit type suffix forces access of that type or nothing
+ * (no suffix, then use Rule 2 & 3)
+ * - Rule 2: If parent volume is R/O, then mount R/O volume by preference, R/W
+ * if not available
+ * - Rule 3: If parent volume is R/W, then only mount R/W volume unless
+ * explicitly told otherwise
+ */
+struct afs_volume *afs_create_volume(struct afs_mount_params *params)
+{
+ struct afs_vldb_entry *vldb;
+ struct afs_volume *volume;
+ unsigned long type_mask = 1UL << params->type;
+
+ vldb = afs_vl_lookup_vldb(params->cell, params->key,
+ params->volname, params->volnamesz);
+ if (IS_ERR(vldb))
+ return ERR_CAST(vldb);
+
+ if (test_bit(AFS_VLDB_QUERY_ERROR, &vldb->flags)) {
+ volume = ERR_PTR(vldb->error);
+ goto error;
+ }
+
+ /* Make the final decision on the type we want */
+ volume = ERR_PTR(-ENOMEDIUM);
+ if (params->force) {
+ if (!(vldb->flags & type_mask))
+ goto error;
+ } else if (test_bit(AFS_VLDB_HAS_RO, &vldb->flags)) {
+ params->type = AFSVL_ROVOL;
+ } else if (test_bit(AFS_VLDB_HAS_RW, &vldb->flags)) {
+ params->type = AFSVL_RWVOL;
+ } else {
+ goto error;
+ }
+
+ type_mask = 1UL << params->type;
+ volume = afs_alloc_volume(params, vldb, type_mask);
+
+error:
+ kfree(vldb);
+ return volume;
+}
+
+/*
+ * Destroy a volume record
+ */
+static void afs_destroy_volume(struct afs_net *net, struct afs_volume *volume)
+{
+ _enter("%p", volume);
+
+#ifdef CONFIG_AFS_FSCACHE
+ ASSERTCMP(volume->cache, ==, NULL);
+#endif
+
+ afs_put_serverlist(net, volume->servers);
+ afs_put_cell(net, volume->cell);
+ kfree(volume);
+
+ _leave(" [destroyed]");
+}
+
+/*
+ * Drop a reference on a volume record.
+ */
+void afs_put_volume(struct afs_cell *cell, struct afs_volume *volume)
+{
+ if (volume) {
+ _enter("%s", volume->name);
+
+ if (atomic_dec_and_test(&volume->usage))
+ afs_destroy_volume(cell->net, volume);
+ }
+}
+
+/*
+ * Activate a volume.
+ */
+void afs_activate_volume(struct afs_volume *volume)
+{
+#ifdef CONFIG_AFS_FSCACHE
+ volume->cache = fscache_acquire_cookie(volume->cell->cache,
+ &afs_volume_cache_index_def,
+ &volume->vid, sizeof(volume->vid),
+ NULL, 0,
+ volume, 0, true);
+#endif
+
+ write_lock(&volume->cell->proc_lock);
+ list_add_tail(&volume->proc_link, &volume->cell->proc_volumes);
+ write_unlock(&volume->cell->proc_lock);
+}
+
+/*
+ * Deactivate a volume.
+ */
+void afs_deactivate_volume(struct afs_volume *volume)
+{
+ _enter("%s", volume->name);
+
+ write_lock(&volume->cell->proc_lock);
+ list_del_init(&volume->proc_link);
+ write_unlock(&volume->cell->proc_lock);
+
+#ifdef CONFIG_AFS_FSCACHE
+ fscache_relinquish_cookie(volume->cache, NULL,
+ test_bit(AFS_VOLUME_DELETED, &volume->flags));
+ volume->cache = NULL;
+#endif
+
+ _leave("");
+}
+
+/*
+ * Query the VL service to update the volume status.
+ */
+static int afs_update_volume_status(struct afs_volume *volume, struct key *key)
+{
+ struct afs_server_list *new, *old, *discard;
+ struct afs_vldb_entry *vldb;
+ char idbuf[16];
+ int ret, idsz;
+
+ _enter("");
+
+ /* We look up an ID by passing it as a decimal string in the
+ * operation's name parameter.
+ */
+ idsz = sprintf(idbuf, "%u", volume->vid);
+
+ vldb = afs_vl_lookup_vldb(volume->cell, key, idbuf, idsz);
+ if (IS_ERR(vldb)) {
+ ret = PTR_ERR(vldb);
+ goto error;
+ }
+
+ /* See if the volume got renamed. */
+ if (vldb->name_len != volume->name_len ||
+ memcmp(vldb->name, volume->name, vldb->name_len) != 0) {
+ /* TODO: Use RCU'd string. */
+ memcpy(volume->name, vldb->name, AFS_MAXVOLNAME);
+ volume->name_len = vldb->name_len;
+ }
+
+ /* See if the volume's server list got updated. */
+ new = afs_alloc_server_list(volume->cell, key,
+ vldb, (1 << volume->type));
+ if (IS_ERR(new)) {
+ ret = PTR_ERR(new);
+ goto error_vldb;
+ }
+
+ write_lock(&volume->servers_lock);
+
+ discard = new;
+ old = volume->servers;
+ if (afs_annotate_server_list(new, old)) {
+ new->seq = volume->servers_seq + 1;
+ volume->servers = new;
+ smp_wmb();
+ volume->servers_seq++;
+ discard = old;
+ }
+
+ volume->update_at = ktime_get_real_seconds() + afs_volume_record_life;
+ clear_bit(AFS_VOLUME_NEEDS_UPDATE, &volume->flags);
+ write_unlock(&volume->servers_lock);
+ ret = 0;
+
+ afs_put_serverlist(volume->cell->net, discard);
+error_vldb:
+ kfree(vldb);
+error:
+ _leave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * Make sure the volume record is up to date.
+ */
+int afs_check_volume_status(struct afs_volume *volume, struct key *key)
+{
+ time64_t now = ktime_get_real_seconds();
+ int ret, retries = 0;
+
+ _enter("");
+
+ if (volume->update_at <= now)
+ set_bit(AFS_VOLUME_NEEDS_UPDATE, &volume->flags);
+
+retry:
+ if (!test_bit(AFS_VOLUME_NEEDS_UPDATE, &volume->flags) &&
+ !test_bit(AFS_VOLUME_WAIT, &volume->flags)) {
+ _leave(" = 0");
+ return 0;
+ }
+
+ if (!test_and_set_bit_lock(AFS_VOLUME_UPDATING, &volume->flags)) {
+ ret = afs_update_volume_status(volume, key);
+ clear_bit_unlock(AFS_VOLUME_WAIT, &volume->flags);
+ clear_bit_unlock(AFS_VOLUME_UPDATING, &volume->flags);
+ wake_up_bit(&volume->flags, AFS_VOLUME_WAIT);
+ _leave(" = %d", ret);
+ return ret;
+ }
+
+ if (!test_bit(AFS_VOLUME_WAIT, &volume->flags)) {
+ _leave(" = 0 [no wait]");
+ return 0;
+ }
+
+ ret = wait_on_bit(&volume->flags, AFS_VOLUME_WAIT, TASK_INTERRUPTIBLE);
+ if (ret == -ERESTARTSYS) {
+ _leave(" = %d", ret);
+ return ret;
+ }
+
+ retries++;
+ if (retries == 4) {
+ _leave(" = -ESTALE");
+ return -ESTALE;
+ }
+ goto retry;
+}