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-rw-r--r--fs/afs/super.c441
1 files changed, 441 insertions, 0 deletions
diff --git a/fs/afs/super.c b/fs/afs/super.c
new file mode 100644
index 000000000000..d6fa8e5999df
--- /dev/null
+++ b/fs/afs/super.c
@@ -0,0 +1,441 @@
+/*
+ * Copyright (c) 2002 Red Hat, Inc. All rights reserved.
+ *
+ * This software may be freely redistributed under the terms of the
+ * GNU General Public License.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * Authors: David Howells <dhowells@redhat.com>
+ * David Woodhouse <dwmw2@cambridge.redhat.com>
+ *
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/fs.h>
+#include <linux/pagemap.h>
+#include "vnode.h"
+#include "volume.h"
+#include "cell.h"
+#include "cmservice.h"
+#include "fsclient.h"
+#include "super.h"
+#include "internal.h"
+
+#define AFS_FS_MAGIC 0x6B414653 /* 'kAFS' */
+
+struct afs_mount_params {
+ int rwpath;
+ struct afs_cell *default_cell;
+ struct afs_volume *volume;
+};
+
+static void afs_i_init_once(void *foo, kmem_cache_t *cachep,
+ unsigned long flags);
+
+static struct super_block *afs_get_sb(struct file_system_type *fs_type,
+ int flags, const char *dev_name,
+ void *data);
+
+static struct inode *afs_alloc_inode(struct super_block *sb);
+
+static void afs_put_super(struct super_block *sb);
+
+static void afs_destroy_inode(struct inode *inode);
+
+static struct file_system_type afs_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "afs",
+ .get_sb = afs_get_sb,
+ .kill_sb = kill_anon_super,
+ .fs_flags = FS_BINARY_MOUNTDATA,
+};
+
+static struct super_operations afs_super_ops = {
+ .statfs = simple_statfs,
+ .alloc_inode = afs_alloc_inode,
+ .drop_inode = generic_delete_inode,
+ .destroy_inode = afs_destroy_inode,
+ .clear_inode = afs_clear_inode,
+ .put_super = afs_put_super,
+};
+
+static kmem_cache_t *afs_inode_cachep;
+static atomic_t afs_count_active_inodes;
+
+/*****************************************************************************/
+/*
+ * initialise the filesystem
+ */
+int __init afs_fs_init(void)
+{
+ int ret;
+
+ _enter("");
+
+ afs_timer_init(&afs_mntpt_expiry_timer, &afs_mntpt_expiry_timer_ops);
+
+ /* create ourselves an inode cache */
+ atomic_set(&afs_count_active_inodes, 0);
+
+ ret = -ENOMEM;
+ afs_inode_cachep = kmem_cache_create("afs_inode_cache",
+ sizeof(struct afs_vnode),
+ 0,
+ SLAB_HWCACHE_ALIGN,
+ afs_i_init_once,
+ NULL);
+ if (!afs_inode_cachep) {
+ printk(KERN_NOTICE "kAFS: Failed to allocate inode cache\n");
+ return ret;
+ }
+
+ /* now export our filesystem to lesser mortals */
+ ret = register_filesystem(&afs_fs_type);
+ if (ret < 0) {
+ kmem_cache_destroy(afs_inode_cachep);
+ kleave(" = %d", ret);
+ return ret;
+ }
+
+ kleave(" = 0");
+ return 0;
+} /* end afs_fs_init() */
+
+/*****************************************************************************/
+/*
+ * clean up the filesystem
+ */
+void __exit afs_fs_exit(void)
+{
+ unregister_filesystem(&afs_fs_type);
+
+ if (atomic_read(&afs_count_active_inodes) != 0) {
+ printk("kAFS: %d active inode objects still present\n",
+ atomic_read(&afs_count_active_inodes));
+ BUG();
+ }
+
+ kmem_cache_destroy(afs_inode_cachep);
+
+} /* end afs_fs_exit() */
+
+/*****************************************************************************/
+/*
+ * check that an argument has a value
+ */
+static int want_arg(char **_value, const char *option)
+{
+ if (!_value || !*_value || !**_value) {
+ printk(KERN_NOTICE "kAFS: %s: argument missing\n", option);
+ return 0;
+ }
+ return 1;
+} /* end want_arg() */
+
+/*****************************************************************************/
+/*
+ * check that there's no subsequent value
+ */
+static int want_no_value(char *const *_value, const char *option)
+{
+ if (*_value && **_value) {
+ printk(KERN_NOTICE "kAFS: %s: Invalid argument: %s\n",
+ option, *_value);
+ return 0;
+ }
+ return 1;
+} /* end want_no_value() */
+
+/*****************************************************************************/
+/*
+ * 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_super_parse_options(struct afs_mount_params *params,
+ char *options,
+ const char **devname)
+{
+ char *key, *value;
+ int ret;
+
+ _enter("%s", options);
+
+ options[PAGE_SIZE - 1] = 0;
+
+ ret = 0;
+ while ((key = strsep(&options, ",")) != 0)
+ {
+ value = strchr(key, '=');
+ if (value)
+ *value++ = 0;
+
+ printk("kAFS: KEY: %s, VAL:%s\n", key, value ?: "-");
+
+ if (strcmp(key, "rwpath") == 0) {
+ if (!want_no_value(&value, "rwpath"))
+ return -EINVAL;
+ params->rwpath = 1;
+ continue;
+ }
+ else if (strcmp(key, "vol") == 0) {
+ if (!want_arg(&value, "vol"))
+ return -EINVAL;
+ *devname = value;
+ continue;
+ }
+ else if (strcmp(key, "cell") == 0) {
+ if (!want_arg(&value, "cell"))
+ return -EINVAL;
+ afs_put_cell(params->default_cell);
+ ret = afs_cell_lookup(value,
+ strlen(value),
+ &params->default_cell);
+ if (ret < 0)
+ return -EINVAL;
+ continue;
+ }
+
+ printk("kAFS: Unknown mount option: '%s'\n", key);
+ ret = -EINVAL;
+ goto error;
+ }
+
+ ret = 0;
+
+ error:
+ _leave(" = %d", ret);
+ return ret;
+} /* end afs_super_parse_options() */
+
+/*****************************************************************************/
+/*
+ * 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)
+{
+ struct afs_mount_params *params = data;
+ struct afs_super_info *as = sb->s_fs_info;
+
+ return as->volume == params->volume;
+} /* end afs_test_super() */
+
+/*****************************************************************************/
+/*
+ * fill in the superblock
+ */
+static int afs_fill_super(struct super_block *sb, void *data, int silent)
+{
+ struct afs_mount_params *params = data;
+ struct afs_super_info *as = NULL;
+ struct afs_fid fid;
+ struct dentry *root = NULL;
+ struct inode *inode = NULL;
+ int ret;
+
+ kenter("");
+
+ /* allocate a superblock info record */
+ as = kmalloc(sizeof(struct afs_super_info), GFP_KERNEL);
+ if (!as) {
+ _leave(" = -ENOMEM");
+ return -ENOMEM;
+ }
+
+ memset(as, 0, sizeof(struct afs_super_info));
+
+ afs_get_volume(params->volume);
+ as->volume = params->volume;
+
+ /* fill in the superblock */
+ sb->s_blocksize = PAGE_CACHE_SIZE;
+ sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
+ sb->s_magic = AFS_FS_MAGIC;
+ sb->s_op = &afs_super_ops;
+ sb->s_fs_info = as;
+
+ /* allocate the root inode and dentry */
+ fid.vid = as->volume->vid;
+ fid.vnode = 1;
+ fid.unique = 1;
+ ret = afs_iget(sb, &fid, &inode);
+ if (ret < 0)
+ goto error;
+
+ ret = -ENOMEM;
+ root = d_alloc_root(inode);
+ if (!root)
+ goto error;
+
+ sb->s_root = root;
+
+ kleave(" = 0");
+ return 0;
+
+ error:
+ iput(inode);
+ afs_put_volume(as->volume);
+ kfree(as);
+
+ sb->s_fs_info = NULL;
+
+ kleave(" = %d", ret);
+ return ret;
+} /* end afs_fill_super() */
+
+/*****************************************************************************/
+/*
+ * get an AFS superblock
+ * - TODO: don't use get_sb_nodev(), but rather call sget() directly
+ */
+static struct super_block *afs_get_sb(struct file_system_type *fs_type,
+ int flags,
+ const char *dev_name,
+ void *options)
+{
+ struct afs_mount_params params;
+ struct super_block *sb;
+ int ret;
+
+ _enter(",,%s,%p", dev_name, options);
+
+ memset(&params, 0, sizeof(params));
+
+ /* start the cache manager */
+ ret = afscm_start();
+ if (ret < 0) {
+ _leave(" = %d", ret);
+ return ERR_PTR(ret);
+ }
+
+ /* parse the options */
+ if (options) {
+ ret = afs_super_parse_options(&params, options, &dev_name);
+ if (ret < 0)
+ goto error;
+ if (!dev_name) {
+ printk("kAFS: no volume name specified\n");
+ ret = -EINVAL;
+ goto error;
+ }
+ }
+
+ /* parse the device name */
+ ret = afs_volume_lookup(dev_name,
+ params.default_cell,
+ params.rwpath,
+ &params.volume);
+ if (ret < 0)
+ goto error;
+
+ /* allocate a deviceless superblock */
+ sb = sget(fs_type, afs_test_super, set_anon_super, &params);
+ if (IS_ERR(sb))
+ goto error;
+
+ sb->s_flags = flags;
+
+ ret = afs_fill_super(sb, &params, flags & MS_VERBOSE ? 1 : 0);
+ if (ret < 0) {
+ up_write(&sb->s_umount);
+ deactivate_super(sb);
+ goto error;
+ }
+ sb->s_flags |= MS_ACTIVE;
+
+ afs_put_volume(params.volume);
+ afs_put_cell(params.default_cell);
+ _leave(" = %p", sb);
+ return sb;
+
+ error:
+ afs_put_volume(params.volume);
+ afs_put_cell(params.default_cell);
+ afscm_stop();
+ _leave(" = %d", ret);
+ return ERR_PTR(ret);
+} /* end afs_get_sb() */
+
+/*****************************************************************************/
+/*
+ * finish the unmounting process on the superblock
+ */
+static void afs_put_super(struct super_block *sb)
+{
+ struct afs_super_info *as = sb->s_fs_info;
+
+ _enter("");
+
+ afs_put_volume(as->volume);
+ afscm_stop();
+
+ _leave("");
+} /* end afs_put_super() */
+
+/*****************************************************************************/
+/*
+ * initialise an inode cache slab element prior to any use
+ */
+static void afs_i_init_once(void *_vnode, kmem_cache_t *cachep,
+ unsigned long flags)
+{
+ struct afs_vnode *vnode = (struct afs_vnode *) _vnode;
+
+ if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) ==
+ SLAB_CTOR_CONSTRUCTOR) {
+ memset(vnode, 0, sizeof(*vnode));
+ inode_init_once(&vnode->vfs_inode);
+ init_waitqueue_head(&vnode->update_waitq);
+ spin_lock_init(&vnode->lock);
+ INIT_LIST_HEAD(&vnode->cb_link);
+ INIT_LIST_HEAD(&vnode->cb_hash_link);
+ afs_timer_init(&vnode->cb_timeout,
+ &afs_vnode_cb_timed_out_ops);
+ }
+
+} /* end afs_i_init_once() */
+
+/*****************************************************************************/
+/*
+ * allocate an AFS inode struct from our slab cache
+ */
+static struct inode *afs_alloc_inode(struct super_block *sb)
+{
+ struct afs_vnode *vnode;
+
+ vnode = (struct afs_vnode *)
+ kmem_cache_alloc(afs_inode_cachep, SLAB_KERNEL);
+ if (!vnode)
+ return NULL;
+
+ atomic_inc(&afs_count_active_inodes);
+
+ memset(&vnode->fid, 0, sizeof(vnode->fid));
+ memset(&vnode->status, 0, sizeof(vnode->status));
+
+ vnode->volume = NULL;
+ vnode->update_cnt = 0;
+ vnode->flags = 0;
+
+ return &vnode->vfs_inode;
+} /* end afs_alloc_inode() */
+
+/*****************************************************************************/
+/*
+ * destroy an AFS inode struct
+ */
+static void afs_destroy_inode(struct inode *inode)
+{
+ _enter("{%lu}", inode->i_ino);
+
+ kmem_cache_free(afs_inode_cachep, AFS_FS_I(inode));
+
+ atomic_dec(&afs_count_active_inodes);
+
+} /* end afs_destroy_inode() */
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-11-27 02:20:11 +0000