From ba9e5e98ca2f808fe92b103a8e6ce5271b10cc89 Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Tue, 28 Oct 2008 16:11:41 +0200 Subject: exofs: super_operations and file_system_type This patch ties all operation vectors into a file system superblock and registers the exofs file_system_type at module's load time. * The file system control block (AKA on-disk superblock) resides in an object with a special ID (defined in common.h). Information included in the file system control block is used to fill the in-memory superblock structure at mount time. This object is created before the file system is used by mkexofs.c It contains information such as: - The file system's magic number - The next inode number to be allocated Signed-off-by: Boaz Harrosh --- fs/exofs/Kbuild | 2 +- fs/exofs/exofs.h | 2 + fs/exofs/inode.c | 186 +++++++++++++++++++ fs/exofs/super.c | 531 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 4 files changed, 720 insertions(+), 1 deletion(-) create mode 100644 fs/exofs/super.c (limited to 'fs/exofs') diff --git a/fs/exofs/Kbuild b/fs/exofs/Kbuild index 0a23f24db8b2..cc2d22db119c 100644 --- a/fs/exofs/Kbuild +++ b/fs/exofs/Kbuild @@ -12,5 +12,5 @@ # Kbuild - Gets included from the Kernels Makefile and build system # -exofs-y := osd.o inode.o file.o symlink.o namei.o dir.o +exofs-y := osd.o inode.o file.o symlink.o namei.o dir.o super.o obj-$(CONFIG_EXOFS_FS) += exofs.o diff --git a/fs/exofs/exofs.h b/fs/exofs/exofs.h index d11982c67e2a..11e11d5c97ba 100644 --- a/fs/exofs/exofs.h +++ b/fs/exofs/exofs.h @@ -140,6 +140,8 @@ int exofs_write_begin(struct file *file, struct address_space *mapping, struct page **pagep, void **fsdata); extern struct inode *exofs_iget(struct super_block *, unsigned long); struct inode *exofs_new_inode(struct inode *, int); +extern int exofs_write_inode(struct inode *, int); +extern void exofs_delete_inode(struct inode *); /* dir.c: */ int exofs_add_link(struct dentry *, struct inode *); diff --git a/fs/exofs/inode.c b/fs/exofs/inode.c index 7c26ba371e1b..ba8d9fab4693 100644 --- a/fs/exofs/inode.c +++ b/fs/exofs/inode.c @@ -1115,3 +1115,189 @@ struct inode *exofs_new_inode(struct inode *dir, int mode) return inode; } + +/* + * struct to pass two arguments to update_inode's callback + */ +struct updatei_args { + struct exofs_sb_info *sbi; + struct exofs_fcb fcb; +}; + +/* + * Callback function from exofs_update_inode(). + */ +static void updatei_done(struct osd_request *or, void *p) +{ + struct updatei_args *args = p; + + osd_end_request(or); + + atomic_dec(&args->sbi->s_curr_pending); + + kfree(args); +} + +/* + * Write the inode to the OSD. Just fill up the struct, and set the attribute + * synchronously or asynchronously depending on the do_sync flag. + */ +static int exofs_update_inode(struct inode *inode, int do_sync) +{ + struct exofs_i_info *oi = exofs_i(inode); + struct super_block *sb = inode->i_sb; + struct exofs_sb_info *sbi = sb->s_fs_info; + struct osd_obj_id obj = {sbi->s_pid, inode->i_ino + EXOFS_OBJ_OFF}; + struct osd_request *or; + struct osd_attr attr; + struct exofs_fcb *fcb; + struct updatei_args *args; + int ret; + + args = kzalloc(sizeof(*args), GFP_KERNEL); + if (!args) + return -ENOMEM; + + fcb = &args->fcb; + + fcb->i_mode = cpu_to_le16(inode->i_mode); + fcb->i_uid = cpu_to_le32(inode->i_uid); + fcb->i_gid = cpu_to_le32(inode->i_gid); + fcb->i_links_count = cpu_to_le16(inode->i_nlink); + fcb->i_ctime = cpu_to_le32(inode->i_ctime.tv_sec); + fcb->i_atime = cpu_to_le32(inode->i_atime.tv_sec); + fcb->i_mtime = cpu_to_le32(inode->i_mtime.tv_sec); + oi->i_commit_size = i_size_read(inode); + fcb->i_size = cpu_to_le64(oi->i_commit_size); + fcb->i_generation = cpu_to_le32(inode->i_generation); + + if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode)) { + if (old_valid_dev(inode->i_rdev)) { + fcb->i_data[0] = + cpu_to_le32(old_encode_dev(inode->i_rdev)); + fcb->i_data[1] = 0; + } else { + fcb->i_data[0] = 0; + fcb->i_data[1] = + cpu_to_le32(new_encode_dev(inode->i_rdev)); + fcb->i_data[2] = 0; + } + } else + memcpy(fcb->i_data, oi->i_data, sizeof(fcb->i_data)); + + or = osd_start_request(sbi->s_dev, GFP_KERNEL); + if (unlikely(!or)) { + EXOFS_ERR("exofs_update_inode: osd_start_request failed.\n"); + ret = -ENOMEM; + goto free_args; + } + + osd_req_set_attributes(or, &obj); + + attr = g_attr_inode_data; + attr.val_ptr = fcb; + osd_req_add_set_attr_list(or, &attr, 1); + + if (!obj_created(oi)) { + EXOFS_DBGMSG("!obj_created\n"); + BUG_ON(!obj_2bcreated(oi)); + wait_event(oi->i_wq, obj_created(oi)); + EXOFS_DBGMSG("wait_event done\n"); + } + + if (do_sync) { + ret = exofs_sync_op(or, sbi->s_timeout, oi->i_cred); + osd_end_request(or); + goto free_args; + } else { + args->sbi = sbi; + + ret = exofs_async_op(or, updatei_done, args, oi->i_cred); + if (ret) { + osd_end_request(or); + goto free_args; + } + atomic_inc(&sbi->s_curr_pending); + goto out; /* deallocation in updatei_done */ + } + +free_args: + kfree(args); +out: + EXOFS_DBGMSG("ret=>%d\n", ret); + return ret; +} + +int exofs_write_inode(struct inode *inode, int wait) +{ + return exofs_update_inode(inode, wait); +} + +/* + * Callback function from exofs_delete_inode() - don't have much cleaning up to + * do. + */ +static void delete_done(struct osd_request *or, void *p) +{ + struct exofs_sb_info *sbi; + osd_end_request(or); + sbi = p; + atomic_dec(&sbi->s_curr_pending); +} + +/* + * Called when the refcount of an inode reaches zero. We remove the object + * from the OSD here. We make sure the object was created before we try and + * delete it. + */ +void exofs_delete_inode(struct inode *inode) +{ + struct exofs_i_info *oi = exofs_i(inode); + struct super_block *sb = inode->i_sb; + struct exofs_sb_info *sbi = sb->s_fs_info; + struct osd_obj_id obj = {sbi->s_pid, inode->i_ino + EXOFS_OBJ_OFF}; + struct osd_request *or; + int ret; + + truncate_inode_pages(&inode->i_data, 0); + + if (is_bad_inode(inode)) + goto no_delete; + + mark_inode_dirty(inode); + exofs_update_inode(inode, inode_needs_sync(inode)); + + inode->i_size = 0; + if (inode->i_blocks) + exofs_truncate(inode); + + clear_inode(inode); + + or = osd_start_request(sbi->s_dev, GFP_KERNEL); + if (unlikely(!or)) { + EXOFS_ERR("exofs_delete_inode: osd_start_request failed\n"); + return; + } + + osd_req_remove_object(or, &obj); + + /* if we are deleting an obj that hasn't been created yet, wait */ + if (!obj_created(oi)) { + BUG_ON(!obj_2bcreated(oi)); + wait_event(oi->i_wq, obj_created(oi)); + } + + ret = exofs_async_op(or, delete_done, sbi, oi->i_cred); + if (ret) { + EXOFS_ERR( + "ERROR: @exofs_delete_inode exofs_async_op failed\n"); + osd_end_request(or); + return; + } + atomic_inc(&sbi->s_curr_pending); + + return; + +no_delete: + clear_inode(inode); +} diff --git a/fs/exofs/super.c b/fs/exofs/super.c new file mode 100644 index 000000000000..b736b117a2a4 --- /dev/null +++ b/fs/exofs/super.c @@ -0,0 +1,531 @@ +/* + * 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 + * + * 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 +#include +#include +#include + +#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; + +/* + * 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; + 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, +}; + +/****************************************************************************** + * 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 "); +MODULE_DESCRIPTION("exofs"); +MODULE_LICENSE("GPL"); + +module_init(init_exofs) +module_exit(exit_exofs) -- cgit v1.2.2