diff options
author | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
---|---|---|
committer | André Fabian Silva Delgado <emulatorman@parabola.nu> | 2015-08-05 17:04:01 -0300 |
commit | 57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch) | |
tree | 5e910f0e82173f4ef4f51111366a3f1299037a7b /fs/hfs/super.c |
Initial import
Diffstat (limited to 'fs/hfs/super.c')
-rw-r--r-- | fs/hfs/super.c | 508 |
1 files changed, 508 insertions, 0 deletions
diff --git a/fs/hfs/super.c b/fs/hfs/super.c new file mode 100644 index 000000000..eee7206c3 --- /dev/null +++ b/fs/hfs/super.c @@ -0,0 +1,508 @@ +/* + * linux/fs/hfs/super.c + * + * Copyright (C) 1995-1997 Paul H. Hargrove + * (C) 2003 Ardis Technologies <roman@ardistech.com> + * This file may be distributed under the terms of the GNU General Public License. + * + * This file contains hfs_read_super(), some of the super_ops and + * init_hfs_fs() and exit_hfs_fs(). The remaining super_ops are in + * inode.c since they deal with inodes. + * + * Based on the minix file system code, (C) 1991, 1992 by Linus Torvalds + */ + +#include <linux/module.h> +#include <linux/blkdev.h> +#include <linux/mount.h> +#include <linux/init.h> +#include <linux/nls.h> +#include <linux/parser.h> +#include <linux/seq_file.h> +#include <linux/slab.h> +#include <linux/vfs.h> + +#include "hfs_fs.h" +#include "btree.h" + +static struct kmem_cache *hfs_inode_cachep; + +MODULE_LICENSE("GPL"); + +static int hfs_sync_fs(struct super_block *sb, int wait) +{ + hfs_mdb_commit(sb); + return 0; +} + +/* + * hfs_put_super() + * + * This is the put_super() entry in the super_operations structure for + * HFS filesystems. The purpose is to release the resources + * associated with the superblock sb. + */ +static void hfs_put_super(struct super_block *sb) +{ + cancel_delayed_work_sync(&HFS_SB(sb)->mdb_work); + hfs_mdb_close(sb); + /* release the MDB's resources */ + hfs_mdb_put(sb); +} + +static void flush_mdb(struct work_struct *work) +{ + struct hfs_sb_info *sbi; + struct super_block *sb; + + sbi = container_of(work, struct hfs_sb_info, mdb_work.work); + sb = sbi->sb; + + spin_lock(&sbi->work_lock); + sbi->work_queued = 0; + spin_unlock(&sbi->work_lock); + + hfs_mdb_commit(sb); +} + +void hfs_mark_mdb_dirty(struct super_block *sb) +{ + struct hfs_sb_info *sbi = HFS_SB(sb); + unsigned long delay; + + if (sb->s_flags & MS_RDONLY) + return; + + spin_lock(&sbi->work_lock); + if (!sbi->work_queued) { + delay = msecs_to_jiffies(dirty_writeback_interval * 10); + queue_delayed_work(system_long_wq, &sbi->mdb_work, delay); + sbi->work_queued = 1; + } + spin_unlock(&sbi->work_lock); +} + +/* + * hfs_statfs() + * + * This is the statfs() entry in the super_operations structure for + * HFS filesystems. The purpose is to return various data about the + * filesystem. + * + * changed f_files/f_ffree to reflect the fs_ablock/free_ablocks. + */ +static int hfs_statfs(struct dentry *dentry, struct kstatfs *buf) +{ + struct super_block *sb = dentry->d_sb; + u64 id = huge_encode_dev(sb->s_bdev->bd_dev); + + buf->f_type = HFS_SUPER_MAGIC; + buf->f_bsize = sb->s_blocksize; + buf->f_blocks = (u32)HFS_SB(sb)->fs_ablocks * HFS_SB(sb)->fs_div; + buf->f_bfree = (u32)HFS_SB(sb)->free_ablocks * HFS_SB(sb)->fs_div; + buf->f_bavail = buf->f_bfree; + buf->f_files = HFS_SB(sb)->fs_ablocks; + buf->f_ffree = HFS_SB(sb)->free_ablocks; + buf->f_fsid.val[0] = (u32)id; + buf->f_fsid.val[1] = (u32)(id >> 32); + buf->f_namelen = HFS_NAMELEN; + + return 0; +} + +static int hfs_remount(struct super_block *sb, int *flags, char *data) +{ + sync_filesystem(sb); + *flags |= MS_NODIRATIME; + if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY)) + return 0; + if (!(*flags & MS_RDONLY)) { + if (!(HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_UNMNT))) { + pr_warn("filesystem was not cleanly unmounted, running fsck.hfs is recommended. leaving read-only.\n"); + sb->s_flags |= MS_RDONLY; + *flags |= MS_RDONLY; + } else if (HFS_SB(sb)->mdb->drAtrb & cpu_to_be16(HFS_SB_ATTRIB_SLOCK)) { + pr_warn("filesystem is marked locked, leaving read-only.\n"); + sb->s_flags |= MS_RDONLY; + *flags |= MS_RDONLY; + } + } + return 0; +} + +static int hfs_show_options(struct seq_file *seq, struct dentry *root) +{ + struct hfs_sb_info *sbi = HFS_SB(root->d_sb); + + if (sbi->s_creator != cpu_to_be32(0x3f3f3f3f)) + seq_printf(seq, ",creator=%.4s", (char *)&sbi->s_creator); + if (sbi->s_type != cpu_to_be32(0x3f3f3f3f)) + seq_printf(seq, ",type=%.4s", (char *)&sbi->s_type); + seq_printf(seq, ",uid=%u,gid=%u", + from_kuid_munged(&init_user_ns, sbi->s_uid), + from_kgid_munged(&init_user_ns, sbi->s_gid)); + if (sbi->s_file_umask != 0133) + seq_printf(seq, ",file_umask=%o", sbi->s_file_umask); + if (sbi->s_dir_umask != 0022) + seq_printf(seq, ",dir_umask=%o", sbi->s_dir_umask); + if (sbi->part >= 0) + seq_printf(seq, ",part=%u", sbi->part); + if (sbi->session >= 0) + seq_printf(seq, ",session=%u", sbi->session); + if (sbi->nls_disk) + seq_printf(seq, ",codepage=%s", sbi->nls_disk->charset); + if (sbi->nls_io) + seq_printf(seq, ",iocharset=%s", sbi->nls_io->charset); + if (sbi->s_quiet) + seq_printf(seq, ",quiet"); + return 0; +} + +static struct inode *hfs_alloc_inode(struct super_block *sb) +{ + struct hfs_inode_info *i; + + i = kmem_cache_alloc(hfs_inode_cachep, GFP_KERNEL); + return i ? &i->vfs_inode : NULL; +} + +static void hfs_i_callback(struct rcu_head *head) +{ + struct inode *inode = container_of(head, struct inode, i_rcu); + kmem_cache_free(hfs_inode_cachep, HFS_I(inode)); +} + +static void hfs_destroy_inode(struct inode *inode) +{ + call_rcu(&inode->i_rcu, hfs_i_callback); +} + +static const struct super_operations hfs_super_operations = { + .alloc_inode = hfs_alloc_inode, + .destroy_inode = hfs_destroy_inode, + .write_inode = hfs_write_inode, + .evict_inode = hfs_evict_inode, + .put_super = hfs_put_super, + .sync_fs = hfs_sync_fs, + .statfs = hfs_statfs, + .remount_fs = hfs_remount, + .show_options = hfs_show_options, +}; + +enum { + opt_uid, opt_gid, opt_umask, opt_file_umask, opt_dir_umask, + opt_part, opt_session, opt_type, opt_creator, opt_quiet, + opt_codepage, opt_iocharset, + opt_err +}; + +static const match_table_t tokens = { + { opt_uid, "uid=%u" }, + { opt_gid, "gid=%u" }, + { opt_umask, "umask=%o" }, + { opt_file_umask, "file_umask=%o" }, + { opt_dir_umask, "dir_umask=%o" }, + { opt_part, "part=%u" }, + { opt_session, "session=%u" }, + { opt_type, "type=%s" }, + { opt_creator, "creator=%s" }, + { opt_quiet, "quiet" }, + { opt_codepage, "codepage=%s" }, + { opt_iocharset, "iocharset=%s" }, + { opt_err, NULL } +}; + +static inline int match_fourchar(substring_t *arg, u32 *result) +{ + if (arg->to - arg->from != 4) + return -EINVAL; + memcpy(result, arg->from, 4); + return 0; +} + +/* + * parse_options() + * + * adapted from linux/fs/msdos/inode.c written 1992,93 by Werner Almesberger + * This function is called by hfs_read_super() to parse the mount options. + */ +static int parse_options(char *options, struct hfs_sb_info *hsb) +{ + char *p; + substring_t args[MAX_OPT_ARGS]; + int tmp, token; + + /* initialize the sb with defaults */ + hsb->s_uid = current_uid(); + hsb->s_gid = current_gid(); + hsb->s_file_umask = 0133; + hsb->s_dir_umask = 0022; + hsb->s_type = hsb->s_creator = cpu_to_be32(0x3f3f3f3f); /* == '????' */ + hsb->s_quiet = 0; + hsb->part = -1; + hsb->session = -1; + + if (!options) + return 1; + + while ((p = strsep(&options, ",")) != NULL) { + if (!*p) + continue; + + token = match_token(p, tokens, args); + switch (token) { + case opt_uid: + if (match_int(&args[0], &tmp)) { + pr_err("uid requires an argument\n"); + return 0; + } + hsb->s_uid = make_kuid(current_user_ns(), (uid_t)tmp); + if (!uid_valid(hsb->s_uid)) { + pr_err("invalid uid %d\n", tmp); + return 0; + } + break; + case opt_gid: + if (match_int(&args[0], &tmp)) { + pr_err("gid requires an argument\n"); + return 0; + } + hsb->s_gid = make_kgid(current_user_ns(), (gid_t)tmp); + if (!gid_valid(hsb->s_gid)) { + pr_err("invalid gid %d\n", tmp); + return 0; + } + break; + case opt_umask: + if (match_octal(&args[0], &tmp)) { + pr_err("umask requires a value\n"); + return 0; + } + hsb->s_file_umask = (umode_t)tmp; + hsb->s_dir_umask = (umode_t)tmp; + break; + case opt_file_umask: + if (match_octal(&args[0], &tmp)) { + pr_err("file_umask requires a value\n"); + return 0; + } + hsb->s_file_umask = (umode_t)tmp; + break; + case opt_dir_umask: + if (match_octal(&args[0], &tmp)) { + pr_err("dir_umask requires a value\n"); + return 0; + } + hsb->s_dir_umask = (umode_t)tmp; + break; + case opt_part: + if (match_int(&args[0], &hsb->part)) { + pr_err("part requires an argument\n"); + return 0; + } + break; + case opt_session: + if (match_int(&args[0], &hsb->session)) { + pr_err("session requires an argument\n"); + return 0; + } + break; + case opt_type: + if (match_fourchar(&args[0], &hsb->s_type)) { + pr_err("type requires a 4 character value\n"); + return 0; + } + break; + case opt_creator: + if (match_fourchar(&args[0], &hsb->s_creator)) { + pr_err("creator requires a 4 character value\n"); + return 0; + } + break; + case opt_quiet: + hsb->s_quiet = 1; + break; + case opt_codepage: + if (hsb->nls_disk) { + pr_err("unable to change codepage\n"); + return 0; + } + p = match_strdup(&args[0]); + if (p) + hsb->nls_disk = load_nls(p); + if (!hsb->nls_disk) { + pr_err("unable to load codepage \"%s\"\n", p); + kfree(p); + return 0; + } + kfree(p); + break; + case opt_iocharset: + if (hsb->nls_io) { + pr_err("unable to change iocharset\n"); + return 0; + } + p = match_strdup(&args[0]); + if (p) + hsb->nls_io = load_nls(p); + if (!hsb->nls_io) { + pr_err("unable to load iocharset \"%s\"\n", p); + kfree(p); + return 0; + } + kfree(p); + break; + default: + return 0; + } + } + + if (hsb->nls_disk && !hsb->nls_io) { + hsb->nls_io = load_nls_default(); + if (!hsb->nls_io) { + pr_err("unable to load default iocharset\n"); + return 0; + } + } + hsb->s_dir_umask &= 0777; + hsb->s_file_umask &= 0577; + + return 1; +} + +/* + * hfs_read_super() + * + * This is the function that is responsible for mounting an HFS + * filesystem. It performs all the tasks necessary to get enough data + * from the disk to read the root inode. This includes parsing the + * mount options, dealing with Macintosh partitions, reading the + * superblock and the allocation bitmap blocks, calling + * hfs_btree_init() to get the necessary data about the extents and + * catalog B-trees and, finally, reading the root inode into memory. + */ +static int hfs_fill_super(struct super_block *sb, void *data, int silent) +{ + struct hfs_sb_info *sbi; + struct hfs_find_data fd; + hfs_cat_rec rec; + struct inode *root_inode; + int res; + + sbi = kzalloc(sizeof(struct hfs_sb_info), GFP_KERNEL); + if (!sbi) + return -ENOMEM; + + sbi->sb = sb; + sb->s_fs_info = sbi; + spin_lock_init(&sbi->work_lock); + INIT_DELAYED_WORK(&sbi->mdb_work, flush_mdb); + + res = -EINVAL; + if (!parse_options((char *)data, sbi)) { + pr_err("unable to parse mount options\n"); + goto bail; + } + + sb->s_op = &hfs_super_operations; + sb->s_flags |= MS_NODIRATIME; + mutex_init(&sbi->bitmap_lock); + + res = hfs_mdb_get(sb); + if (res) { + if (!silent) + pr_warn("can't find a HFS filesystem on dev %s\n", + hfs_mdb_name(sb)); + res = -EINVAL; + goto bail; + } + + /* try to get the root inode */ + res = hfs_find_init(HFS_SB(sb)->cat_tree, &fd); + if (res) + goto bail_no_root; + res = hfs_cat_find_brec(sb, HFS_ROOT_CNID, &fd); + if (!res) { + if (fd.entrylength > sizeof(rec) || fd.entrylength < 0) { + res = -EIO; + goto bail; + } + hfs_bnode_read(fd.bnode, &rec, fd.entryoffset, fd.entrylength); + } + if (res) { + hfs_find_exit(&fd); + goto bail_no_root; + } + res = -EINVAL; + root_inode = hfs_iget(sb, &fd.search_key->cat, &rec); + hfs_find_exit(&fd); + if (!root_inode) + goto bail_no_root; + + sb->s_d_op = &hfs_dentry_operations; + res = -ENOMEM; + sb->s_root = d_make_root(root_inode); + if (!sb->s_root) + goto bail_no_root; + + /* everything's okay */ + return 0; + +bail_no_root: + pr_err("get root inode failed\n"); +bail: + hfs_mdb_put(sb); + return res; +} + +static struct dentry *hfs_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data) +{ + return mount_bdev(fs_type, flags, dev_name, data, hfs_fill_super); +} + +static struct file_system_type hfs_fs_type = { + .owner = THIS_MODULE, + .name = "hfs", + .mount = hfs_mount, + .kill_sb = kill_block_super, + .fs_flags = FS_REQUIRES_DEV, +}; +MODULE_ALIAS_FS("hfs"); + +static void hfs_init_once(void *p) +{ + struct hfs_inode_info *i = p; + + inode_init_once(&i->vfs_inode); +} + +static int __init init_hfs_fs(void) +{ + int err; + + hfs_inode_cachep = kmem_cache_create("hfs_inode_cache", + sizeof(struct hfs_inode_info), 0, SLAB_HWCACHE_ALIGN, + hfs_init_once); + if (!hfs_inode_cachep) + return -ENOMEM; + err = register_filesystem(&hfs_fs_type); + if (err) + kmem_cache_destroy(hfs_inode_cachep); + return err; +} + +static void __exit exit_hfs_fs(void) +{ + unregister_filesystem(&hfs_fs_type); + + /* + * Make sure all delayed rcu free inodes are flushed before we + * destroy cache. + */ + rcu_barrier(); + kmem_cache_destroy(hfs_inode_cachep); +} + +module_init(init_hfs_fs) +module_exit(exit_hfs_fs) |