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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /fs/affs/super.c
Initial import
Diffstat (limited to 'fs/affs/super.c')
-rw-r--r--fs/affs/super.c649
1 files changed, 649 insertions, 0 deletions
diff --git a/fs/affs/super.c b/fs/affs/super.c
new file mode 100644
index 000000000..3f89c9e05
--- /dev/null
+++ b/fs/affs/super.c
@@ -0,0 +1,649 @@
+/*
+ * linux/fs/affs/inode.c
+ *
+ * (c) 1996 Hans-Joachim Widmaier - Rewritten
+ *
+ * (C) 1993 Ray Burr - Modified for Amiga FFS filesystem.
+ *
+ * (C) 1992 Eric Youngdale Modified for ISO 9660 filesystem.
+ *
+ * (C) 1991 Linus Torvalds - minix filesystem
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/statfs.h>
+#include <linux/parser.h>
+#include <linux/magic.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/writeback.h>
+#include "affs.h"
+
+static int affs_statfs(struct dentry *dentry, struct kstatfs *buf);
+static int affs_remount (struct super_block *sb, int *flags, char *data);
+
+static void
+affs_commit_super(struct super_block *sb, int wait)
+{
+ struct affs_sb_info *sbi = AFFS_SB(sb);
+ struct buffer_head *bh = sbi->s_root_bh;
+ struct affs_root_tail *tail = AFFS_ROOT_TAIL(sb, bh);
+
+ lock_buffer(bh);
+ secs_to_datestamp(get_seconds(), &tail->disk_change);
+ affs_fix_checksum(sb, bh);
+ unlock_buffer(bh);
+
+ mark_buffer_dirty(bh);
+ if (wait)
+ sync_dirty_buffer(bh);
+}
+
+static void
+affs_put_super(struct super_block *sb)
+{
+ struct affs_sb_info *sbi = AFFS_SB(sb);
+ pr_debug("%s()\n", __func__);
+
+ cancel_delayed_work_sync(&sbi->sb_work);
+}
+
+static int
+affs_sync_fs(struct super_block *sb, int wait)
+{
+ affs_commit_super(sb, wait);
+ return 0;
+}
+
+static void flush_superblock(struct work_struct *work)
+{
+ struct affs_sb_info *sbi;
+ struct super_block *sb;
+
+ sbi = container_of(work, struct affs_sb_info, sb_work.work);
+ sb = sbi->sb;
+
+ spin_lock(&sbi->work_lock);
+ sbi->work_queued = 0;
+ spin_unlock(&sbi->work_lock);
+
+ affs_commit_super(sb, 1);
+}
+
+void affs_mark_sb_dirty(struct super_block *sb)
+{
+ struct affs_sb_info *sbi = AFFS_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->sb_work, delay);
+ sbi->work_queued = 1;
+ }
+ spin_unlock(&sbi->work_lock);
+}
+
+static struct kmem_cache * affs_inode_cachep;
+
+static struct inode *affs_alloc_inode(struct super_block *sb)
+{
+ struct affs_inode_info *i;
+
+ i = kmem_cache_alloc(affs_inode_cachep, GFP_KERNEL);
+ if (!i)
+ return NULL;
+
+ i->vfs_inode.i_version = 1;
+ i->i_lc = NULL;
+ i->i_ext_bh = NULL;
+ i->i_pa_cnt = 0;
+
+ return &i->vfs_inode;
+}
+
+static void affs_i_callback(struct rcu_head *head)
+{
+ struct inode *inode = container_of(head, struct inode, i_rcu);
+ kmem_cache_free(affs_inode_cachep, AFFS_I(inode));
+}
+
+static void affs_destroy_inode(struct inode *inode)
+{
+ call_rcu(&inode->i_rcu, affs_i_callback);
+}
+
+static void init_once(void *foo)
+{
+ struct affs_inode_info *ei = (struct affs_inode_info *) foo;
+
+ sema_init(&ei->i_link_lock, 1);
+ sema_init(&ei->i_ext_lock, 1);
+ inode_init_once(&ei->vfs_inode);
+}
+
+static int __init init_inodecache(void)
+{
+ affs_inode_cachep = kmem_cache_create("affs_inode_cache",
+ sizeof(struct affs_inode_info),
+ 0, (SLAB_RECLAIM_ACCOUNT|
+ SLAB_MEM_SPREAD),
+ init_once);
+ if (affs_inode_cachep == NULL)
+ return -ENOMEM;
+ return 0;
+}
+
+static void destroy_inodecache(void)
+{
+ /*
+ * Make sure all delayed rcu free inodes are flushed before we
+ * destroy cache.
+ */
+ rcu_barrier();
+ kmem_cache_destroy(affs_inode_cachep);
+}
+
+static const struct super_operations affs_sops = {
+ .alloc_inode = affs_alloc_inode,
+ .destroy_inode = affs_destroy_inode,
+ .write_inode = affs_write_inode,
+ .evict_inode = affs_evict_inode,
+ .put_super = affs_put_super,
+ .sync_fs = affs_sync_fs,
+ .statfs = affs_statfs,
+ .remount_fs = affs_remount,
+ .show_options = generic_show_options,
+};
+
+enum {
+ Opt_bs, Opt_mode, Opt_mufs, Opt_notruncate, Opt_prefix, Opt_protect,
+ Opt_reserved, Opt_root, Opt_setgid, Opt_setuid,
+ Opt_verbose, Opt_volume, Opt_ignore, Opt_err,
+};
+
+static const match_table_t tokens = {
+ {Opt_bs, "bs=%u"},
+ {Opt_mode, "mode=%o"},
+ {Opt_mufs, "mufs"},
+ {Opt_notruncate, "nofilenametruncate"},
+ {Opt_prefix, "prefix=%s"},
+ {Opt_protect, "protect"},
+ {Opt_reserved, "reserved=%u"},
+ {Opt_root, "root=%u"},
+ {Opt_setgid, "setgid=%u"},
+ {Opt_setuid, "setuid=%u"},
+ {Opt_verbose, "verbose"},
+ {Opt_volume, "volume=%s"},
+ {Opt_ignore, "grpquota"},
+ {Opt_ignore, "noquota"},
+ {Opt_ignore, "quota"},
+ {Opt_ignore, "usrquota"},
+ {Opt_err, NULL},
+};
+
+static int
+parse_options(char *options, kuid_t *uid, kgid_t *gid, int *mode, int *reserved, s32 *root,
+ int *blocksize, char **prefix, char *volume, unsigned long *mount_opts)
+{
+ char *p;
+ substring_t args[MAX_OPT_ARGS];
+
+ /* Fill in defaults */
+
+ *uid = current_uid();
+ *gid = current_gid();
+ *reserved = 2;
+ *root = -1;
+ *blocksize = -1;
+ volume[0] = ':';
+ volume[1] = 0;
+ *mount_opts = 0;
+ if (!options)
+ return 1;
+
+ while ((p = strsep(&options, ",")) != NULL) {
+ int token, n, option;
+ if (!*p)
+ continue;
+
+ token = match_token(p, tokens, args);
+ switch (token) {
+ case Opt_bs:
+ if (match_int(&args[0], &n))
+ return 0;
+ if (n != 512 && n != 1024 && n != 2048
+ && n != 4096) {
+ pr_warn("Invalid blocksize (512, 1024, 2048, 4096 allowed)\n");
+ return 0;
+ }
+ *blocksize = n;
+ break;
+ case Opt_mode:
+ if (match_octal(&args[0], &option))
+ return 0;
+ *mode = option & 0777;
+ affs_set_opt(*mount_opts, SF_SETMODE);
+ break;
+ case Opt_mufs:
+ affs_set_opt(*mount_opts, SF_MUFS);
+ break;
+ case Opt_notruncate:
+ affs_set_opt(*mount_opts, SF_NO_TRUNCATE);
+ break;
+ case Opt_prefix:
+ *prefix = match_strdup(&args[0]);
+ if (!*prefix)
+ return 0;
+ affs_set_opt(*mount_opts, SF_PREFIX);
+ break;
+ case Opt_protect:
+ affs_set_opt(*mount_opts, SF_IMMUTABLE);
+ break;
+ case Opt_reserved:
+ if (match_int(&args[0], reserved))
+ return 0;
+ break;
+ case Opt_root:
+ if (match_int(&args[0], root))
+ return 0;
+ break;
+ case Opt_setgid:
+ if (match_int(&args[0], &option))
+ return 0;
+ *gid = make_kgid(current_user_ns(), option);
+ if (!gid_valid(*gid))
+ return 0;
+ affs_set_opt(*mount_opts, SF_SETGID);
+ break;
+ case Opt_setuid:
+ if (match_int(&args[0], &option))
+ return 0;
+ *uid = make_kuid(current_user_ns(), option);
+ if (!uid_valid(*uid))
+ return 0;
+ affs_set_opt(*mount_opts, SF_SETUID);
+ break;
+ case Opt_verbose:
+ affs_set_opt(*mount_opts, SF_VERBOSE);
+ break;
+ case Opt_volume: {
+ char *vol = match_strdup(&args[0]);
+ if (!vol)
+ return 0;
+ strlcpy(volume, vol, 32);
+ kfree(vol);
+ break;
+ }
+ case Opt_ignore:
+ /* Silently ignore the quota options */
+ break;
+ default:
+ pr_warn("Unrecognized mount option \"%s\" or missing value\n",
+ p);
+ return 0;
+ }
+ }
+ return 1;
+}
+
+/* This function definitely needs to be split up. Some fine day I'll
+ * hopefully have the guts to do so. Until then: sorry for the mess.
+ */
+
+static int affs_fill_super(struct super_block *sb, void *data, int silent)
+{
+ struct affs_sb_info *sbi;
+ struct buffer_head *root_bh = NULL;
+ struct buffer_head *boot_bh;
+ struct inode *root_inode = NULL;
+ s32 root_block;
+ int size, blocksize;
+ u32 chksum;
+ int num_bm;
+ int i, j;
+ kuid_t uid;
+ kgid_t gid;
+ int reserved;
+ unsigned long mount_flags;
+ int tmp_flags; /* fix remount prototype... */
+ u8 sig[4];
+ int ret;
+
+ save_mount_options(sb, data);
+
+ pr_debug("read_super(%s)\n", data ? (const char *)data : "no options");
+
+ sb->s_magic = AFFS_SUPER_MAGIC;
+ sb->s_op = &affs_sops;
+ sb->s_flags |= MS_NODIRATIME;
+
+ sbi = kzalloc(sizeof(struct affs_sb_info), GFP_KERNEL);
+ if (!sbi)
+ return -ENOMEM;
+
+ sb->s_fs_info = sbi;
+ sbi->sb = sb;
+ mutex_init(&sbi->s_bmlock);
+ spin_lock_init(&sbi->symlink_lock);
+ spin_lock_init(&sbi->work_lock);
+ INIT_DELAYED_WORK(&sbi->sb_work, flush_superblock);
+
+ if (!parse_options(data,&uid,&gid,&i,&reserved,&root_block,
+ &blocksize,&sbi->s_prefix,
+ sbi->s_volume, &mount_flags)) {
+ pr_err("Error parsing options\n");
+ return -EINVAL;
+ }
+ /* N.B. after this point s_prefix must be released */
+
+ sbi->s_flags = mount_flags;
+ sbi->s_mode = i;
+ sbi->s_uid = uid;
+ sbi->s_gid = gid;
+ sbi->s_reserved= reserved;
+
+ /* Get the size of the device in 512-byte blocks.
+ * If we later see that the partition uses bigger
+ * blocks, we will have to change it.
+ */
+
+ size = sb->s_bdev->bd_inode->i_size >> 9;
+ pr_debug("initial blocksize=%d, #blocks=%d\n", 512, size);
+
+ affs_set_blocksize(sb, PAGE_SIZE);
+ /* Try to find root block. Its location depends on the block size. */
+
+ i = 512;
+ j = 4096;
+ if (blocksize > 0) {
+ i = j = blocksize;
+ size = size / (blocksize / 512);
+ }
+ for (blocksize = i; blocksize <= j; blocksize <<= 1, size >>= 1) {
+ sbi->s_root_block = root_block;
+ if (root_block < 0)
+ sbi->s_root_block = (reserved + size - 1) / 2;
+ pr_debug("setting blocksize to %d\n", blocksize);
+ affs_set_blocksize(sb, blocksize);
+ sbi->s_partition_size = size;
+
+ /* The root block location that was calculated above is not
+ * correct if the partition size is an odd number of 512-
+ * byte blocks, which will be rounded down to a number of
+ * 1024-byte blocks, and if there were an even number of
+ * reserved blocks. Ideally, all partition checkers should
+ * report the real number of blocks of the real blocksize,
+ * but since this just cannot be done, we have to try to
+ * find the root block anyways. In the above case, it is one
+ * block behind the calculated one. So we check this one, too.
+ */
+ for (num_bm = 0; num_bm < 2; num_bm++) {
+ pr_debug("Dev %s, trying root=%u, bs=%d, "
+ "size=%d, reserved=%d\n",
+ sb->s_id,
+ sbi->s_root_block + num_bm,
+ blocksize, size, reserved);
+ root_bh = affs_bread(sb, sbi->s_root_block + num_bm);
+ if (!root_bh)
+ continue;
+ if (!affs_checksum_block(sb, root_bh) &&
+ be32_to_cpu(AFFS_ROOT_HEAD(root_bh)->ptype) == T_SHORT &&
+ be32_to_cpu(AFFS_ROOT_TAIL(sb, root_bh)->stype) == ST_ROOT) {
+ sbi->s_hashsize = blocksize / 4 - 56;
+ sbi->s_root_block += num_bm;
+ goto got_root;
+ }
+ affs_brelse(root_bh);
+ root_bh = NULL;
+ }
+ }
+ if (!silent)
+ pr_err("No valid root block on device %s\n", sb->s_id);
+ return -EINVAL;
+
+ /* N.B. after this point bh must be released */
+got_root:
+ /* Keep super block in cache */
+ sbi->s_root_bh = root_bh;
+ root_block = sbi->s_root_block;
+
+ /* Find out which kind of FS we have */
+ boot_bh = sb_bread(sb, 0);
+ if (!boot_bh) {
+ pr_err("Cannot read boot block\n");
+ return -EINVAL;
+ }
+ memcpy(sig, boot_bh->b_data, 4);
+ brelse(boot_bh);
+ chksum = be32_to_cpu(*(__be32 *)sig);
+
+ /* Dircache filesystems are compatible with non-dircache ones
+ * when reading. As long as they aren't supported, writing is
+ * not recommended.
+ */
+ if ((chksum == FS_DCFFS || chksum == MUFS_DCFFS || chksum == FS_DCOFS
+ || chksum == MUFS_DCOFS) && !(sb->s_flags & MS_RDONLY)) {
+ pr_notice("Dircache FS - mounting %s read only\n", sb->s_id);
+ sb->s_flags |= MS_RDONLY;
+ }
+ switch (chksum) {
+ case MUFS_FS:
+ case MUFS_INTLFFS:
+ case MUFS_DCFFS:
+ affs_set_opt(sbi->s_flags, SF_MUFS);
+ /* fall thru */
+ case FS_INTLFFS:
+ case FS_DCFFS:
+ affs_set_opt(sbi->s_flags, SF_INTL);
+ break;
+ case MUFS_FFS:
+ affs_set_opt(sbi->s_flags, SF_MUFS);
+ break;
+ case FS_FFS:
+ break;
+ case MUFS_OFS:
+ affs_set_opt(sbi->s_flags, SF_MUFS);
+ /* fall thru */
+ case FS_OFS:
+ affs_set_opt(sbi->s_flags, SF_OFS);
+ sb->s_flags |= MS_NOEXEC;
+ break;
+ case MUFS_DCOFS:
+ case MUFS_INTLOFS:
+ affs_set_opt(sbi->s_flags, SF_MUFS);
+ case FS_DCOFS:
+ case FS_INTLOFS:
+ affs_set_opt(sbi->s_flags, SF_INTL);
+ affs_set_opt(sbi->s_flags, SF_OFS);
+ sb->s_flags |= MS_NOEXEC;
+ break;
+ default:
+ pr_err("Unknown filesystem on device %s: %08X\n",
+ sb->s_id, chksum);
+ return -EINVAL;
+ }
+
+ if (affs_test_opt(mount_flags, SF_VERBOSE)) {
+ u8 len = AFFS_ROOT_TAIL(sb, root_bh)->disk_name[0];
+ pr_notice("Mounting volume \"%.*s\": Type=%.3s\\%c, Blocksize=%d\n",
+ len > 31 ? 31 : len,
+ AFFS_ROOT_TAIL(sb, root_bh)->disk_name + 1,
+ sig, sig[3] + '0', blocksize);
+ }
+
+ sb->s_flags |= MS_NODEV | MS_NOSUID;
+
+ sbi->s_data_blksize = sb->s_blocksize;
+ if (affs_test_opt(sbi->s_flags, SF_OFS))
+ sbi->s_data_blksize -= 24;
+
+ tmp_flags = sb->s_flags;
+ ret = affs_init_bitmap(sb, &tmp_flags);
+ if (ret)
+ return ret;
+ sb->s_flags = tmp_flags;
+
+ /* set up enough so that it can read an inode */
+
+ root_inode = affs_iget(sb, root_block);
+ if (IS_ERR(root_inode))
+ return PTR_ERR(root_inode);
+
+ if (affs_test_opt(AFFS_SB(sb)->s_flags, SF_INTL))
+ sb->s_d_op = &affs_intl_dentry_operations;
+ else
+ sb->s_d_op = &affs_dentry_operations;
+
+ sb->s_root = d_make_root(root_inode);
+ if (!sb->s_root) {
+ pr_err("AFFS: Get root inode failed\n");
+ return -ENOMEM;
+ }
+
+ pr_debug("s_flags=%lX\n", sb->s_flags);
+ return 0;
+}
+
+static int
+affs_remount(struct super_block *sb, int *flags, char *data)
+{
+ struct affs_sb_info *sbi = AFFS_SB(sb);
+ int blocksize;
+ kuid_t uid;
+ kgid_t gid;
+ int mode;
+ int reserved;
+ int root_block;
+ unsigned long mount_flags;
+ int res = 0;
+ char *new_opts;
+ char volume[32];
+ char *prefix = NULL;
+
+ new_opts = kstrdup(data, GFP_KERNEL);
+ if (!new_opts)
+ return -ENOMEM;
+
+ pr_debug("%s(flags=0x%x,opts=\"%s\")\n", __func__, *flags, data);
+
+ sync_filesystem(sb);
+ *flags |= MS_NODIRATIME;
+
+ memcpy(volume, sbi->s_volume, 32);
+ if (!parse_options(data, &uid, &gid, &mode, &reserved, &root_block,
+ &blocksize, &prefix, volume,
+ &mount_flags)) {
+ kfree(prefix);
+ kfree(new_opts);
+ return -EINVAL;
+ }
+
+ flush_delayed_work(&sbi->sb_work);
+ replace_mount_options(sb, new_opts);
+
+ sbi->s_flags = mount_flags;
+ sbi->s_mode = mode;
+ sbi->s_uid = uid;
+ sbi->s_gid = gid;
+ /* protect against readers */
+ spin_lock(&sbi->symlink_lock);
+ if (prefix) {
+ kfree(sbi->s_prefix);
+ sbi->s_prefix = prefix;
+ }
+ memcpy(sbi->s_volume, volume, 32);
+ spin_unlock(&sbi->symlink_lock);
+
+ if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
+ return 0;
+
+ if (*flags & MS_RDONLY)
+ affs_free_bitmap(sb);
+ else
+ res = affs_init_bitmap(sb, flags);
+
+ return res;
+}
+
+static int
+affs_statfs(struct dentry *dentry, struct kstatfs *buf)
+{
+ struct super_block *sb = dentry->d_sb;
+ int free;
+ u64 id = huge_encode_dev(sb->s_bdev->bd_dev);
+
+ pr_debug("%s() partsize=%d, reserved=%d\n",
+ __func__, AFFS_SB(sb)->s_partition_size,
+ AFFS_SB(sb)->s_reserved);
+
+ free = affs_count_free_blocks(sb);
+ buf->f_type = AFFS_SUPER_MAGIC;
+ buf->f_bsize = sb->s_blocksize;
+ buf->f_blocks = AFFS_SB(sb)->s_partition_size - AFFS_SB(sb)->s_reserved;
+ buf->f_bfree = free;
+ buf->f_bavail = free;
+ buf->f_fsid.val[0] = (u32)id;
+ buf->f_fsid.val[1] = (u32)(id >> 32);
+ buf->f_namelen = AFFSNAMEMAX;
+ return 0;
+}
+
+static struct dentry *affs_mount(struct file_system_type *fs_type,
+ int flags, const char *dev_name, void *data)
+{
+ return mount_bdev(fs_type, flags, dev_name, data, affs_fill_super);
+}
+
+static void affs_kill_sb(struct super_block *sb)
+{
+ struct affs_sb_info *sbi = AFFS_SB(sb);
+ kill_block_super(sb);
+ if (sbi) {
+ affs_free_bitmap(sb);
+ affs_brelse(sbi->s_root_bh);
+ kfree(sbi->s_prefix);
+ mutex_destroy(&sbi->s_bmlock);
+ kfree(sbi);
+ }
+}
+
+static struct file_system_type affs_fs_type = {
+ .owner = THIS_MODULE,
+ .name = "affs",
+ .mount = affs_mount,
+ .kill_sb = affs_kill_sb,
+ .fs_flags = FS_REQUIRES_DEV,
+};
+MODULE_ALIAS_FS("affs");
+
+static int __init init_affs_fs(void)
+{
+ int err = init_inodecache();
+ if (err)
+ goto out1;
+ err = register_filesystem(&affs_fs_type);
+ if (err)
+ goto out;
+ return 0;
+out:
+ destroy_inodecache();
+out1:
+ return err;
+}
+
+static void __exit exit_affs_fs(void)
+{
+ unregister_filesystem(&affs_fs_type);
+ destroy_inodecache();
+}
+
+MODULE_DESCRIPTION("Amiga filesystem support for Linux");
+MODULE_LICENSE("GPL");
+
+module_init(init_affs_fs)
+module_exit(exit_affs_fs)