/* AFS superblock handling
*
- * Copyright (c) 2002, 2007 Red Hat, Inc. All rights reserved.
+ * Copyright (c) 2002, 2007, 2018 Red Hat, Inc. All rights reserved.
*
* This software may be freely redistributed under the terms of the
* GNU General Public License.
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
-#include <linux/parser.h>
+#include <linux/fs_parser.h>
#include <linux/statfs.h>
#include <linux/sched.h>
#include <linux/nsproxy.h>
#include "internal.h"
static void afs_i_init_once(void *foo);
-static struct dentry *afs_mount(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *data);
static void afs_kill_super(struct super_block *sb);
static struct inode *afs_alloc_inode(struct super_block *sb);
static void afs_destroy_inode(struct inode *inode);
static int afs_statfs(struct dentry *dentry, struct kstatfs *buf);
static int afs_show_devname(struct seq_file *m, struct dentry *root);
static int afs_show_options(struct seq_file *m, struct dentry *root);
+static int afs_init_fs_context(struct fs_context *fc);
+static const struct fs_parameter_description afs_fs_parameters;
struct file_system_type afs_fs_type = {
- .owner = THIS_MODULE,
- .name = "afs",
- .mount = afs_mount,
- .kill_sb = afs_kill_super,
- .fs_flags = 0,
+ .owner = THIS_MODULE,
+ .name = "afs",
+ .init_fs_context = afs_init_fs_context,
+ .parameters = &afs_fs_parameters,
+ .kill_sb = afs_kill_super,
+ .fs_flags = 0,
};
MODULE_ALIAS_FS("afs");
static struct kmem_cache *afs_inode_cachep;
static atomic_t afs_count_active_inodes;
-enum {
- afs_no_opt,
- afs_opt_cell,
- afs_opt_dyn,
- afs_opt_rwpath,
- afs_opt_vol,
- afs_opt_autocell,
+enum afs_param {
+ Opt_autocell,
+ Opt_cell,
+ Opt_dyn,
+ Opt_rwpath,
+ Opt_source,
+ Opt_vol,
};
-static const match_table_t afs_options_list = {
- { afs_opt_cell, "cell=%s" },
- { afs_opt_dyn, "dyn" },
- { afs_opt_rwpath, "rwpath" },
- { afs_opt_vol, "vol=%s" },
- { afs_opt_autocell, "autocell" },
- { afs_no_opt, NULL },
+static const struct fs_parameter_spec afs_param_specs[] = {
+ fsparam_flag ("autocell", Opt_autocell),
+ fsparam_string("cell", Opt_cell),
+ fsparam_flag ("dyn", Opt_dyn),
+ fsparam_flag ("rwpath", Opt_rwpath),
+ fsparam_string("source", Opt_source),
+ fsparam_string("vol", Opt_vol),
+ {}
+};
+
+static const struct fs_parameter_description afs_fs_parameters = {
+ .name = "kAFS",
+ .specs = afs_param_specs,
};
/*
}
/*
- * parse the mount options
- * - this function has been shamelessly adapted from the ext3 fs which
- * shamelessly adapted it from the msdos fs
- */
-static int afs_parse_options(struct afs_mount_params *params,
- char *options, const char **devname)
-{
- struct afs_cell *cell;
- substring_t args[MAX_OPT_ARGS];
- char *p;
- int token;
-
- _enter("%s", options);
-
- options[PAGE_SIZE - 1] = 0;
-
- while ((p = strsep(&options, ","))) {
- if (!*p)
- continue;
-
- token = match_token(p, afs_options_list, args);
- switch (token) {
- case afs_opt_cell:
- rcu_read_lock();
- cell = afs_lookup_cell_rcu(params->net,
- args[0].from,
- args[0].to - args[0].from);
- rcu_read_unlock();
- if (IS_ERR(cell))
- return PTR_ERR(cell);
- afs_put_cell(params->net, params->cell);
- params->cell = cell;
- break;
-
- case afs_opt_rwpath:
- params->rwpath = true;
- break;
-
- case afs_opt_vol:
- *devname = args[0].from;
- break;
-
- case afs_opt_autocell:
- params->autocell = true;
- break;
-
- case afs_opt_dyn:
- params->dyn_root = true;
- break;
-
- default:
- printk(KERN_ERR "kAFS:"
- " Unknown or invalid mount option: '%s'\n", p);
- return -EINVAL;
- }
- }
-
- _leave(" = 0");
- return 0;
-}
-
-/*
- * parse a device name to get cell name, volume name, volume type and R/W
- * selector
- * - this can be one of the following:
+ * Parse the source name to get cell name, volume name, volume type and R/W
+ * selector.
+ *
+ * This can be one of the following:
* "%[cell:]volume[.]" R/W volume
* "#[cell:]volume[.]" R/O or R/W volume (rwpath=0),
* or R/W (rwpath=1) volume
* "%[cell:]volume.backup" Backup volume
* "#[cell:]volume.backup" Backup volume
*/
-static int afs_parse_device_name(struct afs_mount_params *params,
- const char *name)
+static int afs_parse_source(struct fs_context *fc, struct fs_parameter *param)
{
+ struct afs_fs_context *ctx = fc->fs_private;
struct afs_cell *cell;
- const char *cellname, *suffix;
+ const char *cellname, *suffix, *name = param->string;
int cellnamesz;
_enter(",%s", name);
}
if ((name[0] != '%' && name[0] != '#') || !name[1]) {
+ /* To use dynroot, we don't want to have to provide a source */
+ if (strcmp(name, "none") == 0) {
+ ctx->no_cell = true;
+ return 0;
+ }
printk(KERN_ERR "kAFS: unparsable volume name\n");
return -EINVAL;
}
/* determine the type of volume we're looking for */
- params->type = AFSVL_ROVOL;
- params->force = false;
- if (params->rwpath || name[0] == '%') {
- params->type = AFSVL_RWVOL;
- params->force = true;
+ ctx->type = AFSVL_ROVOL;
+ ctx->force = false;
+ if (ctx->rwpath || name[0] == '%') {
+ ctx->type = AFSVL_RWVOL;
+ ctx->force = true;
}
name++;
/* split the cell name out if there is one */
- params->volname = strchr(name, ':');
- if (params->volname) {
+ ctx->volname = strchr(name, ':');
+ if (ctx->volname) {
cellname = name;
- cellnamesz = params->volname - name;
- params->volname++;
+ cellnamesz = ctx->volname - name;
+ ctx->volname++;
} else {
- params->volname = name;
+ ctx->volname = name;
cellname = NULL;
cellnamesz = 0;
}
/* the volume type is further affected by a possible suffix */
- suffix = strrchr(params->volname, '.');
+ suffix = strrchr(ctx->volname, '.');
if (suffix) {
if (strcmp(suffix, ".readonly") == 0) {
- params->type = AFSVL_ROVOL;
- params->force = true;
+ ctx->type = AFSVL_ROVOL;
+ ctx->force = true;
} else if (strcmp(suffix, ".backup") == 0) {
- params->type = AFSVL_BACKVOL;
- params->force = true;
+ ctx->type = AFSVL_BACKVOL;
+ ctx->force = true;
} else if (suffix[1] == 0) {
} else {
suffix = NULL;
}
}
- params->volnamesz = suffix ?
- suffix - params->volname : strlen(params->volname);
+ ctx->volnamesz = suffix ?
+ suffix - ctx->volname : strlen(ctx->volname);
_debug("cell %*.*s [%p]",
- cellnamesz, cellnamesz, cellname ?: "", params->cell);
+ cellnamesz, cellnamesz, cellname ?: "", ctx->cell);
/* lookup the cell record */
- if (cellname || !params->cell) {
- cell = afs_lookup_cell(params->net, cellname, cellnamesz,
+ if (cellname) {
+ cell = afs_lookup_cell(ctx->net, cellname, cellnamesz,
NULL, false);
if (IS_ERR(cell)) {
- printk(KERN_ERR "kAFS: unable to lookup cell '%*.*s'\n",
+ pr_err("kAFS: unable to lookup cell '%*.*s'\n",
cellnamesz, cellnamesz, cellname ?: "");
return PTR_ERR(cell);
}
- afs_put_cell(params->net, params->cell);
- params->cell = cell;
+ afs_put_cell(ctx->net, ctx->cell);
+ ctx->cell = cell;
}
_debug("CELL:%s [%p] VOLUME:%*.*s SUFFIX:%s TYPE:%d%s",
- params->cell->name, params->cell,
- params->volnamesz, params->volnamesz, params->volname,
- suffix ?: "-", params->type, params->force ? " FORCE" : "");
+ ctx->cell->name, ctx->cell,
+ ctx->volnamesz, ctx->volnamesz, ctx->volname,
+ suffix ?: "-", ctx->type, ctx->force ? " FORCE" : "");
+
+ fc->source = param->string;
+ param->string = NULL;
+ return 0;
+}
+
+/*
+ * Parse a single mount parameter.
+ */
+static int afs_parse_param(struct fs_context *fc, struct fs_parameter *param)
+{
+ struct fs_parse_result result;
+ struct afs_fs_context *ctx = fc->fs_private;
+ struct afs_cell *cell;
+ int opt;
+
+ opt = fs_parse(fc, &afs_fs_parameters, param, &result);
+ if (opt < 0)
+ return opt;
+
+ switch (opt) {
+ case Opt_cell:
+ if (param->size <= 0)
+ return -EINVAL;
+ if (param->size > AFS_MAXCELLNAME)
+ return -ENAMETOOLONG;
+
+ rcu_read_lock();
+ cell = afs_lookup_cell_rcu(ctx->net, param->string, param->size);
+ rcu_read_unlock();
+ if (IS_ERR(cell))
+ return PTR_ERR(cell);
+ afs_put_cell(ctx->net, ctx->cell);
+ ctx->cell = cell;
+ break;
+
+ case Opt_source:
+ return afs_parse_source(fc, param);
+
+ case Opt_autocell:
+ ctx->autocell = true;
+ break;
+
+ case Opt_dyn:
+ ctx->dyn_root = true;
+ break;
+
+ case Opt_rwpath:
+ ctx->rwpath = true;
+ break;
+
+ case Opt_vol:
+ return invalf(fc, "'vol' param is obsolete");
+
+ default:
+ return -EINVAL;
+ }
+
+ _leave(" = 0");
+ return 0;
+}
+
+/*
+ * Validate the options, get the cell key and look up the volume.
+ */
+static int afs_validate_fc(struct fs_context *fc)
+{
+ struct afs_fs_context *ctx = fc->fs_private;
+ struct afs_volume *volume;
+ struct key *key;
+
+ if (!ctx->dyn_root) {
+ if (ctx->no_cell) {
+ pr_warn("kAFS: Can only specify source 'none' with -o dyn\n");
+ return -EINVAL;
+ }
+
+ if (!ctx->cell) {
+ pr_warn("kAFS: No cell specified\n");
+ return -EDESTADDRREQ;
+ }
+
+ /* We try to do the mount securely. */
+ key = afs_request_key(ctx->cell);
+ if (IS_ERR(key))
+ return PTR_ERR(key);
+
+ ctx->key = key;
+
+ if (ctx->volume) {
+ afs_put_volume(ctx->cell, ctx->volume);
+ ctx->volume = NULL;
+ }
+
+ volume = afs_create_volume(ctx);
+ if (IS_ERR(volume))
+ return PTR_ERR(volume);
+
+ ctx->volume = volume;
+ }
return 0;
}
/*
* check a superblock to see if it's the one we're looking for
*/
-static int afs_test_super(struct super_block *sb, void *data)
+static int afs_test_super(struct super_block *sb, struct fs_context *fc)
{
- struct afs_super_info *as1 = data;
+ struct afs_fs_context *ctx = fc->fs_private;
struct afs_super_info *as = AFS_FS_S(sb);
- return (as->net_ns == as1->net_ns &&
+ return (as->net_ns == fc->net_ns &&
as->volume &&
- as->volume->vid == as1->volume->vid &&
+ as->volume->vid == ctx->volume->vid &&
!as->dyn_root);
}
-static int afs_dynroot_test_super(struct super_block *sb, void *data)
+static int afs_dynroot_test_super(struct super_block *sb, struct fs_context *fc)
{
- struct afs_super_info *as1 = data;
struct afs_super_info *as = AFS_FS_S(sb);
- return (as->net_ns == as1->net_ns &&
+ return (as->net_ns == fc->net_ns &&
as->dyn_root);
}
-static int afs_set_super(struct super_block *sb, void *data)
+static int afs_set_super(struct super_block *sb, struct fs_context *fc)
{
- struct afs_super_info *as = data;
-
- sb->s_fs_info = as;
return set_anon_super(sb, NULL);
}
/*
* fill in the superblock
*/
-static int afs_fill_super(struct super_block *sb,
- struct afs_mount_params *params)
+static int afs_fill_super(struct super_block *sb, struct afs_fs_context *ctx)
{
struct afs_super_info *as = AFS_FS_S(sb);
struct afs_fid fid;
fid.vnode = 1;
fid.vnode_hi = 0;
fid.unique = 1;
- inode = afs_iget(sb, params->key, &fid, NULL, NULL, NULL);
+ inode = afs_iget(sb, ctx->key, &fid, NULL, NULL, NULL);
}
if (IS_ERR(inode))
return PTR_ERR(inode);
- if (params->autocell || params->dyn_root)
+ if (ctx->autocell || as->dyn_root)
set_bit(AFS_VNODE_AUTOCELL, &AFS_FS_I(inode)->flags);
ret = -ENOMEM;
return ret;
}
-static struct afs_super_info *afs_alloc_sbi(struct afs_mount_params *params)
+static struct afs_super_info *afs_alloc_sbi(struct fs_context *fc)
{
+ struct afs_fs_context *ctx = fc->fs_private;
struct afs_super_info *as;
as = kzalloc(sizeof(struct afs_super_info), GFP_KERNEL);
if (as) {
- as->net_ns = get_net(params->net_ns);
- if (params->dyn_root)
+ as->net_ns = get_net(fc->net_ns);
+ if (ctx->dyn_root) {
as->dyn_root = true;
- else
- as->cell = afs_get_cell(params->cell);
+ } else {
+ as->cell = afs_get_cell(ctx->cell);
+ as->volume = __afs_get_volume(ctx->volume);
+ }
}
return as;
}
if (as->dyn_root)
afs_dynroot_depopulate(sb);
-
+
/* Clear the callback interests (which will do ilookup5) before
* deactivating the superblock.
*/
}
/*
- * get an AFS superblock
+ * Get an AFS superblock and root directory.
*/
-static struct dentry *afs_mount(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *options)
+static int afs_get_tree(struct fs_context *fc)
{
- struct afs_mount_params params;
+ struct afs_fs_context *ctx = fc->fs_private;
struct super_block *sb;
- struct afs_volume *candidate;
- struct key *key;
struct afs_super_info *as;
int ret;
- _enter(",,%s,%p", dev_name, options);
-
- memset(¶ms, 0, sizeof(params));
-
- ret = -EINVAL;
- if (current->nsproxy->net_ns != &init_net)
+ ret = afs_validate_fc(fc);
+ if (ret)
goto error;
- params.net_ns = current->nsproxy->net_ns;
- params.net = afs_net(params.net_ns);
-
- /* parse the options and device name */
- if (options) {
- ret = afs_parse_options(¶ms, options, &dev_name);
- if (ret < 0)
- goto error;
- }
-
- if (!params.dyn_root) {
- ret = afs_parse_device_name(¶ms, dev_name);
- if (ret < 0)
- goto error;
- /* try and do the mount securely */
- key = afs_request_key(params.cell);
- if (IS_ERR(key)) {
- _leave(" = %ld [key]", PTR_ERR(key));
- ret = PTR_ERR(key);
- goto error;
- }
- params.key = key;
- }
+ _enter("");
/* allocate a superblock info record */
ret = -ENOMEM;
- as = afs_alloc_sbi(¶ms);
+ as = afs_alloc_sbi(fc);
if (!as)
- goto error_key;
-
- if (!params.dyn_root) {
- /* Assume we're going to need a volume record; at the very
- * least we can use it to update the volume record if we have
- * one already. This checks that the volume exists within the
- * cell.
- */
- candidate = afs_create_volume(¶ms);
- if (IS_ERR(candidate)) {
- ret = PTR_ERR(candidate);
- goto error_as;
- }
-
- as->volume = candidate;
- }
+ goto error;
+ fc->s_fs_info = as;
/* allocate a deviceless superblock */
- sb = sget(fs_type,
- as->dyn_root ? afs_dynroot_test_super : afs_test_super,
- afs_set_super, flags, as);
+ sb = sget_fc(fc,
+ as->dyn_root ? afs_dynroot_test_super : afs_test_super,
+ afs_set_super);
if (IS_ERR(sb)) {
ret = PTR_ERR(sb);
- goto error_as;
+ goto error;
}
if (!sb->s_root) {
/* initial superblock/root creation */
_debug("create");
- ret = afs_fill_super(sb, ¶ms);
+ ret = afs_fill_super(sb, ctx);
if (ret < 0)
goto error_sb;
- as = NULL;
sb->s_flags |= SB_ACTIVE;
} else {
_debug("reuse");
ASSERTCMP(sb->s_flags, &, SB_ACTIVE);
- afs_destroy_sbi(as);
- as = NULL;
}
- afs_put_cell(params.net, params.cell);
- key_put(params.key);
+ fc->root = dget(sb->s_root);
_leave(" = 0 [%p]", sb);
- return dget(sb->s_root);
+ return 0;
error_sb:
deactivate_locked_super(sb);
- goto error_key;
-error_as:
- afs_destroy_sbi(as);
-error_key:
- key_put(params.key);
error:
- afs_put_cell(params.net, params.cell);
_leave(" = %d", ret);
- return ERR_PTR(ret);
+ return ret;
+}
+
+static void afs_free_fc(struct fs_context *fc)
+{
+ struct afs_fs_context *ctx = fc->fs_private;
+
+ afs_destroy_sbi(fc->s_fs_info);
+ afs_put_volume(ctx->cell, ctx->volume);
+ afs_put_cell(ctx->net, ctx->cell);
+ key_put(ctx->key);
+ kfree(ctx);
+}
+
+static const struct fs_context_operations afs_context_ops = {
+ .free = afs_free_fc,
+ .parse_param = afs_parse_param,
+ .get_tree = afs_get_tree,
+};
+
+/*
+ * Set up the filesystem mount context.
+ */
+static int afs_init_fs_context(struct fs_context *fc)
+{
+ struct afs_fs_context *ctx;
+ struct afs_cell *cell;
+
+ if (current->nsproxy->net_ns != &init_net)
+ return -EINVAL;
+
+ ctx = kzalloc(sizeof(struct afs_fs_context), GFP_KERNEL);
+ if (!ctx)
+ return -ENOMEM;
+
+ ctx->type = AFSVL_ROVOL;
+ ctx->net = afs_net(fc->net_ns);
+
+ /* Default to the workstation cell. */
+ rcu_read_lock();
+ cell = afs_lookup_cell_rcu(ctx->net, NULL, 0);
+ rcu_read_unlock();
+ if (IS_ERR(cell))
+ cell = NULL;
+ ctx->cell = cell;
+
+ fc->fs_private = ctx;
+ fc->ops = &afs_context_ops;
+ return 0;
}
/*