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-rw-r--r--fs/exofs/super.c584
1 files changed, 584 insertions, 0 deletions
diff --git a/fs/exofs/super.c b/fs/exofs/super.c
new file mode 100644
index 000000000000..9f1985e857e2
--- /dev/null
+++ b/fs/exofs/super.c
@@ -0,0 +1,584 @@
+/*
+ * Copyright (C) 2005, 2006
+ * Avishay Traeger (avishay@gmail.com) (avishay@il.ibm.com)
+ * Copyright (C) 2005, 2006
+ * International Business Machines
+ * Copyright (C) 2008, 2009
+ * Boaz Harrosh <bharrosh@panasas.com>
+ *
+ * Copyrights for code taken from ext2:
+ * Copyright (C) 1992, 1993, 1994, 1995
+ * Remy Card (card@masi.ibp.fr)
+ * Laboratoire MASI - Institut Blaise Pascal
+ * Universite Pierre et Marie Curie (Paris VI)
+ * from
+ * linux/fs/minix/inode.c
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ *
+ * This file is part of exofs.
+ *
+ * exofs 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. Since it is based on ext2, and the only
+ * valid version of GPL for the Linux kernel is version 2, the only valid
+ * version of GPL for exofs is version 2.
+ *
+ * exofs is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with exofs; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <linux/string.h>
+#include <linux/parser.h>
+#include <linux/vfs.h>
+#include <linux/random.h>
+#include <linux/exportfs.h>
+
+#include "exofs.h"
+
+/******************************************************************************
+ * MOUNT OPTIONS
+ *****************************************************************************/
+
+/*
+ * struct to hold what we get from mount options
+ */
+struct exofs_mountopt {
+ const char *dev_name;
+ uint64_t pid;
+ int timeout;
+};
+
+/*
+ * exofs-specific mount-time options.
+ */
+enum { Opt_pid, Opt_to, Opt_mkfs, Opt_format, Opt_err };
+
+/*
+ * Our mount-time options. These should ideally be 64-bit unsigned, but the
+ * kernel's parsing functions do not currently support that. 32-bit should be
+ * sufficient for most applications now.
+ */
+static match_table_t tokens = {
+ {Opt_pid, "pid=%u"},
+ {Opt_to, "to=%u"},
+ {Opt_err, NULL}
+};
+
+/*
+ * The main option parsing method. Also makes sure that all of the mandatory
+ * mount options were set.
+ */
+static int parse_options(char *options, struct exofs_mountopt *opts)
+{
+ char *p;
+ substring_t args[MAX_OPT_ARGS];
+ int option;
+ bool s_pid = false;
+
+ EXOFS_DBGMSG("parse_options %s\n", options);
+ /* defaults */
+ memset(opts, 0, sizeof(*opts));
+ opts->timeout = BLK_DEFAULT_SG_TIMEOUT;
+
+ while ((p = strsep(&options, ",")) != NULL) {
+ int token;
+ char str[32];
+
+ if (!*p)
+ continue;
+
+ token = match_token(p, tokens, args);
+ switch (token) {
+ case Opt_pid:
+ if (0 == match_strlcpy(str, &args[0], sizeof(str)))
+ return -EINVAL;
+ opts->pid = simple_strtoull(str, NULL, 0);
+ if (opts->pid < EXOFS_MIN_PID) {
+ EXOFS_ERR("Partition ID must be >= %u",
+ EXOFS_MIN_PID);
+ return -EINVAL;
+ }
+ s_pid = 1;
+ break;
+ case Opt_to:
+ if (match_int(&args[0], &option))
+ return -EINVAL;
+ if (option <= 0) {
+ EXOFS_ERR("Timout must be > 0");
+ return -EINVAL;
+ }
+ opts->timeout = option * HZ;
+ break;
+ }
+ }
+
+ if (!s_pid) {
+ EXOFS_ERR("Need to specify the following options:\n");
+ EXOFS_ERR(" -o pid=pid_no_to_use\n");
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/******************************************************************************
+ * INODE CACHE
+ *****************************************************************************/
+
+/*
+ * Our inode cache. Isn't it pretty?
+ */
+static struct kmem_cache *exofs_inode_cachep;
+
+/*
+ * Allocate an inode in the cache
+ */
+static struct inode *exofs_alloc_inode(struct super_block *sb)
+{
+ struct exofs_i_info *oi;
+
+ oi = kmem_cache_alloc(exofs_inode_cachep, GFP_KERNEL);
+ if (!oi)
+ return NULL;
+
+ oi->vfs_inode.i_version = 1;
+ return &oi->vfs_inode;
+}
+
+/*
+ * Remove an inode from the cache
+ */
+static void exofs_destroy_inode(struct inode *inode)
+{
+ kmem_cache_free(exofs_inode_cachep, exofs_i(inode));
+}
+
+/*
+ * Initialize the inode
+ */
+static void exofs_init_once(void *foo)
+{
+ struct exofs_i_info *oi = foo;
+
+ inode_init_once(&oi->vfs_inode);
+}
+
+/*
+ * Create and initialize the inode cache
+ */
+static int init_inodecache(void)
+{
+ exofs_inode_cachep = kmem_cache_create("exofs_inode_cache",
+ sizeof(struct exofs_i_info), 0,
+ SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD,
+ exofs_init_once);
+ if (exofs_inode_cachep == NULL)
+ return -ENOMEM;
+ return 0;
+}
+
+/*
+ * Destroy the inode cache
+ */
+static void destroy_inodecache(void)
+{
+ kmem_cache_destroy(exofs_inode_cachep);
+}
+
+/******************************************************************************
+ * SUPERBLOCK FUNCTIONS
+ *****************************************************************************/
+static const struct super_operations exofs_sops;
+static const struct export_operations exofs_export_ops;
+
+/*
+ * Write the superblock to the OSD
+ */
+static void exofs_write_super(struct super_block *sb)
+{
+ struct exofs_sb_info *sbi;
+ struct exofs_fscb *fscb;
+ struct osd_request *or;
+ struct osd_obj_id obj;
+ int ret;
+
+ fscb = kzalloc(sizeof(struct exofs_fscb), GFP_KERNEL);
+ if (!fscb) {
+ EXOFS_ERR("exofs_write_super: memory allocation failed.\n");
+ return;
+ }
+
+ lock_kernel();
+ sbi = sb->s_fs_info;
+ fscb->s_nextid = cpu_to_le64(sbi->s_nextid);
+ fscb->s_numfiles = cpu_to_le32(sbi->s_numfiles);
+ fscb->s_magic = cpu_to_le16(sb->s_magic);
+ fscb->s_newfs = 0;
+
+ or = osd_start_request(sbi->s_dev, GFP_KERNEL);
+ if (unlikely(!or)) {
+ EXOFS_ERR("exofs_write_super: osd_start_request failed.\n");
+ goto out;
+ }
+
+ obj.partition = sbi->s_pid;
+ obj.id = EXOFS_SUPER_ID;
+ ret = osd_req_write_kern(or, &obj, 0, fscb, sizeof(*fscb));
+ if (unlikely(ret)) {
+ EXOFS_ERR("exofs_write_super: osd_req_write_kern failed.\n");
+ goto out;
+ }
+
+ ret = exofs_sync_op(or, sbi->s_timeout, sbi->s_cred);
+ if (unlikely(ret)) {
+ EXOFS_ERR("exofs_write_super: exofs_sync_op failed.\n");
+ goto out;
+ }
+ sb->s_dirt = 0;
+
+out:
+ if (or)
+ osd_end_request(or);
+ unlock_kernel();
+ kfree(fscb);
+}
+
+/*
+ * This function is called when the vfs is freeing the superblock. We just
+ * need to free our own part.
+ */
+static void exofs_put_super(struct super_block *sb)
+{
+ int num_pend;
+ struct exofs_sb_info *sbi = sb->s_fs_info;
+
+ /* make sure there are no pending commands */
+ for (num_pend = atomic_read(&sbi->s_curr_pending); num_pend > 0;
+ num_pend = atomic_read(&sbi->s_curr_pending)) {
+ wait_queue_head_t wq;
+ init_waitqueue_head(&wq);
+ wait_event_timeout(wq,
+ (atomic_read(&sbi->s_curr_pending) == 0),
+ msecs_to_jiffies(100));
+ }
+
+ osduld_put_device(sbi->s_dev);
+ kfree(sb->s_fs_info);
+ sb->s_fs_info = NULL;
+}
+
+/*
+ * Read the superblock from the OSD and fill in the fields
+ */
+static int exofs_fill_super(struct super_block *sb, void *data, int silent)
+{
+ struct inode *root;
+ struct exofs_mountopt *opts = data;
+ struct exofs_sb_info *sbi; /*extended info */
+ struct exofs_fscb fscb; /*on-disk superblock info */
+ struct osd_request *or = NULL;
+ struct osd_obj_id obj;
+ int ret;
+
+ sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
+ if (!sbi)
+ return -ENOMEM;
+ sb->s_fs_info = sbi;
+
+ /* use mount options to fill superblock */
+ sbi->s_dev = osduld_path_lookup(opts->dev_name);
+ if (IS_ERR(sbi->s_dev)) {
+ ret = PTR_ERR(sbi->s_dev);
+ sbi->s_dev = NULL;
+ goto free_sbi;
+ }
+
+ sbi->s_pid = opts->pid;
+ sbi->s_timeout = opts->timeout;
+
+ /* fill in some other data by hand */
+ memset(sb->s_id, 0, sizeof(sb->s_id));
+ strcpy(sb->s_id, "exofs");
+ sb->s_blocksize = EXOFS_BLKSIZE;
+ sb->s_blocksize_bits = EXOFS_BLKSHIFT;
+ sb->s_maxbytes = MAX_LFS_FILESIZE;
+ atomic_set(&sbi->s_curr_pending, 0);
+ sb->s_bdev = NULL;
+ sb->s_dev = 0;
+
+ /* read data from on-disk superblock object */
+ obj.partition = sbi->s_pid;
+ obj.id = EXOFS_SUPER_ID;
+ exofs_make_credential(sbi->s_cred, &obj);
+
+ or = osd_start_request(sbi->s_dev, GFP_KERNEL);
+ if (unlikely(!or)) {
+ if (!silent)
+ EXOFS_ERR(
+ "exofs_fill_super: osd_start_request failed.\n");
+ ret = -ENOMEM;
+ goto free_sbi;
+ }
+ ret = osd_req_read_kern(or, &obj, 0, &fscb, sizeof(fscb));
+ if (unlikely(ret)) {
+ if (!silent)
+ EXOFS_ERR(
+ "exofs_fill_super: osd_req_read_kern failed.\n");
+ ret = -ENOMEM;
+ goto free_sbi;
+ }
+
+ ret = exofs_sync_op(or, sbi->s_timeout, sbi->s_cred);
+ if (unlikely(ret)) {
+ if (!silent)
+ EXOFS_ERR("exofs_fill_super: exofs_sync_op failed.\n");
+ ret = -EIO;
+ goto free_sbi;
+ }
+
+ sb->s_magic = le16_to_cpu(fscb.s_magic);
+ sbi->s_nextid = le64_to_cpu(fscb.s_nextid);
+ sbi->s_numfiles = le32_to_cpu(fscb.s_numfiles);
+
+ /* make sure what we read from the object store is correct */
+ if (sb->s_magic != EXOFS_SUPER_MAGIC) {
+ if (!silent)
+ EXOFS_ERR("ERROR: Bad magic value\n");
+ ret = -EINVAL;
+ goto free_sbi;
+ }
+
+ /* start generation numbers from a random point */
+ get_random_bytes(&sbi->s_next_generation, sizeof(u32));
+ spin_lock_init(&sbi->s_next_gen_lock);
+
+ /* set up operation vectors */
+ sb->s_op = &exofs_sops;
+ sb->s_export_op = &exofs_export_ops;
+ root = exofs_iget(sb, EXOFS_ROOT_ID - EXOFS_OBJ_OFF);
+ if (IS_ERR(root)) {
+ EXOFS_ERR("ERROR: exofs_iget failed\n");
+ ret = PTR_ERR(root);
+ goto free_sbi;
+ }
+ sb->s_root = d_alloc_root(root);
+ if (!sb->s_root) {
+ iput(root);
+ EXOFS_ERR("ERROR: get root inode failed\n");
+ ret = -ENOMEM;
+ goto free_sbi;
+ }
+
+ if (!S_ISDIR(root->i_mode)) {
+ dput(sb->s_root);
+ sb->s_root = NULL;
+ EXOFS_ERR("ERROR: corrupt root inode (mode = %hd)\n",
+ root->i_mode);
+ ret = -EINVAL;
+ goto free_sbi;
+ }
+
+ ret = 0;
+out:
+ if (or)
+ osd_end_request(or);
+ return ret;
+
+free_sbi:
+ osduld_put_device(sbi->s_dev); /* NULL safe */
+ kfree(sbi);
+ goto out;
+}
+
+/*
+ * Set up the superblock (calls exofs_fill_super eventually)
+ */
+static int exofs_get_sb(struct file_system_type *type,
+ int flags, const char *dev_name,
+ void *data, struct vfsmount *mnt)
+{
+ struct exofs_mountopt opts;
+ int ret;
+
+ ret = parse_options(data, &opts);
+ if (ret)
+ return ret;
+
+ opts.dev_name = dev_name;
+ return get_sb_nodev(type, flags, &opts, exofs_fill_super, mnt);
+}
+
+/*
+ * Return information about the file system state in the buffer. This is used
+ * by the 'df' command, for example.
+ */
+static int exofs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+ struct super_block *sb = dentry->d_sb;
+ struct exofs_sb_info *sbi = sb->s_fs_info;
+ struct osd_obj_id obj = {sbi->s_pid, 0};
+ struct osd_attr attrs[] = {
+ ATTR_DEF(OSD_APAGE_PARTITION_QUOTAS,
+ OSD_ATTR_PQ_CAPACITY_QUOTA, sizeof(__be64)),
+ ATTR_DEF(OSD_APAGE_PARTITION_INFORMATION,
+ OSD_ATTR_PI_USED_CAPACITY, sizeof(__be64)),
+ };
+ uint64_t capacity = ULLONG_MAX;
+ uint64_t used = ULLONG_MAX;
+ struct osd_request *or;
+ uint8_t cred_a[OSD_CAP_LEN];
+ int ret;
+
+ /* get used/capacity attributes */
+ exofs_make_credential(cred_a, &obj);
+
+ or = osd_start_request(sbi->s_dev, GFP_KERNEL);
+ if (unlikely(!or)) {
+ EXOFS_DBGMSG("exofs_statfs: osd_start_request failed.\n");
+ return -ENOMEM;
+ }
+
+ osd_req_get_attributes(or, &obj);
+ osd_req_add_get_attr_list(or, attrs, ARRAY_SIZE(attrs));
+ ret = exofs_sync_op(or, sbi->s_timeout, cred_a);
+ if (unlikely(ret))
+ goto out;
+
+ ret = extract_attr_from_req(or, &attrs[0]);
+ if (likely(!ret))
+ capacity = get_unaligned_be64(attrs[0].val_ptr);
+ else
+ EXOFS_DBGMSG("exofs_statfs: get capacity failed.\n");
+
+ ret = extract_attr_from_req(or, &attrs[1]);
+ if (likely(!ret))
+ used = get_unaligned_be64(attrs[1].val_ptr);
+ else
+ EXOFS_DBGMSG("exofs_statfs: get used-space failed.\n");
+
+ /* fill in the stats buffer */
+ buf->f_type = EXOFS_SUPER_MAGIC;
+ buf->f_bsize = EXOFS_BLKSIZE;
+ buf->f_blocks = (capacity >> EXOFS_BLKSHIFT);
+ buf->f_bfree = ((capacity - used) >> EXOFS_BLKSHIFT);
+ buf->f_bavail = buf->f_bfree;
+ buf->f_files = sbi->s_numfiles;
+ buf->f_ffree = EXOFS_MAX_ID - sbi->s_numfiles;
+ buf->f_namelen = EXOFS_NAME_LEN;
+
+out:
+ osd_end_request(or);
+ return ret;
+}
+
+static const struct super_operations exofs_sops = {
+ .alloc_inode = exofs_alloc_inode,
+ .destroy_inode = exofs_destroy_inode,
+ .write_inode = exofs_write_inode,
+ .delete_inode = exofs_delete_inode,
+ .put_super = exofs_put_super,
+ .write_super = exofs_write_super,
+ .statfs = exofs_statfs,
+};
+
+/******************************************************************************
+ * EXPORT OPERATIONS
+ *****************************************************************************/
+
+struct dentry *exofs_get_parent(struct dentry *child)
+{
+ unsigned long ino = exofs_parent_ino(child);
+
+ if (!ino)
+ return NULL;
+
+ return d_obtain_alias(exofs_iget(child->d_inode->i_sb, ino));
+}
+
+static struct inode *exofs_nfs_get_inode(struct super_block *sb,
+ u64 ino, u32 generation)
+{
+ struct inode *inode;
+
+ inode = exofs_iget(sb, ino);
+ if (IS_ERR(inode))
+ return ERR_CAST(inode);
+ if (generation && inode->i_generation != generation) {
+ /* we didn't find the right inode.. */
+ iput(inode);
+ return ERR_PTR(-ESTALE);
+ }
+ return inode;
+}
+
+static struct dentry *exofs_fh_to_dentry(struct super_block *sb,
+ struct fid *fid, int fh_len, int fh_type)
+{
+ return generic_fh_to_dentry(sb, fid, fh_len, fh_type,
+ exofs_nfs_get_inode);
+}
+
+static struct dentry *exofs_fh_to_parent(struct super_block *sb,
+ struct fid *fid, int fh_len, int fh_type)
+{
+ return generic_fh_to_parent(sb, fid, fh_len, fh_type,
+ exofs_nfs_get_inode);
+}
+
+static const struct export_operations exofs_export_ops = {
+ .fh_to_dentry = exofs_fh_to_dentry,
+ .fh_to_parent = exofs_fh_to_parent,
+ .get_parent = exofs_get_parent,
+};
+
+/******************************************************************************
+ * INSMOD/RMMOD
+ *****************************************************************************/
+
+/*
+ * struct that describes this file system
+ */
+static struct file_system_type exofs_type = {
+ .owner = THIS_MODULE,
+ .name = "exofs",
+ .get_sb = exofs_get_sb,
+ .kill_sb = generic_shutdown_super,
+};
+
+static int __init init_exofs(void)
+{
+ int err;
+
+ err = init_inodecache();
+ if (err)
+ goto out;
+
+ err = register_filesystem(&exofs_type);
+ if (err)
+ goto out_d;
+
+ return 0;
+out_d:
+ destroy_inodecache();
+out:
+ return err;
+}
+
+static void __exit exit_exofs(void)
+{
+ unregister_filesystem(&exofs_type);
+ destroy_inodecache();
+}
+
+MODULE_AUTHOR("Avishay Traeger <avishay@gmail.com>");
+MODULE_DESCRIPTION("exofs");
+MODULE_LICENSE("GPL");
+
+module_init(init_exofs)
+module_exit(exit_exofs)
generated by cgit v1.2.3 (git 2.39.0) at 2024-11-28 19:12:35 +0300