diff options
Diffstat (limited to 'fs/cramfs/inode.c')
| -rw-r--r-- | fs/cramfs/inode.c | 244 |
1 files changed, 133 insertions, 111 deletions
diff --git a/fs/cramfs/inode.c b/fs/cramfs/inode.c index dd3634e4c96..ddcfe590b8a 100644 --- a/fs/cramfs/inode.c +++ b/fs/cramfs/inode.c @@ -17,15 +17,30 @@ #include <linux/init.h> #include <linux/string.h> #include <linux/blkdev.h> -#include <linux/cramfs_fs.h> #include <linux/slab.h> -#include <linux/cramfs_fs_sb.h> -#include <linux/buffer_head.h> #include <linux/vfs.h> #include <linux/mutex.h> - +#include <uapi/linux/cramfs_fs.h> #include <asm/uaccess.h> +#include "internal.h" + +/* + * cramfs super-block data in memory + */ +struct cramfs_sb_info { + unsigned long magic; + unsigned long size; + unsigned long blocks; + unsigned long files; + unsigned long flags; +}; + +static inline struct cramfs_sb_info *CRAMFS_SB(struct super_block *sb) +{ + return sb->s_fs_info; +} + static const struct super_operations cramfs_ops; static const struct inode_operations cramfs_dir_inode_operations; static const struct file_operations cramfs_directory_operations; @@ -34,69 +49,82 @@ static const struct address_space_operations cramfs_aops; static DEFINE_MUTEX(read_mutex); -/* These two macros may change in future, to provide better st_ino - semantics. */ -#define CRAMINO(x) (((x)->offset && (x)->size)?(x)->offset<<2:1) +/* These macros may change in future, to provide better st_ino semantics. */ #define OFFSET(x) ((x)->i_ino) - -static int cramfs_iget5_test(struct inode *inode, void *opaque) +static unsigned long cramino(const struct cramfs_inode *cino, unsigned int offset) { - struct cramfs_inode *cramfs_inode = opaque; - return inode->i_ino == CRAMINO(cramfs_inode) && inode->i_ino != 1; -} - -static int cramfs_iget5_set(struct inode *inode, void *opaque) -{ - struct cramfs_inode *cramfs_inode = opaque; - inode->i_ino = CRAMINO(cramfs_inode); - return 0; + if (!cino->offset) + return offset + 1; + if (!cino->size) + return offset + 1; + + /* + * The file mode test fixes buggy mkcramfs implementations where + * cramfs_inode->offset is set to a non zero value for entries + * which did not contain data, like devices node and fifos. + */ + switch (cino->mode & S_IFMT) { + case S_IFREG: + case S_IFDIR: + case S_IFLNK: + return cino->offset << 2; + default: + break; + } + return offset + 1; } static struct inode *get_cramfs_inode(struct super_block *sb, - struct cramfs_inode * cramfs_inode) + const struct cramfs_inode *cramfs_inode, unsigned int offset) { - struct inode *inode = iget5_locked(sb, CRAMINO(cramfs_inode), - cramfs_iget5_test, cramfs_iget5_set, - cramfs_inode); + struct inode *inode; static struct timespec zerotime; - if (inode && (inode->i_state & I_NEW)) { - inode->i_mode = cramfs_inode->mode; - inode->i_uid = cramfs_inode->uid; + inode = iget_locked(sb, cramino(cramfs_inode, offset)); + if (!inode) + return ERR_PTR(-ENOMEM); + if (!(inode->i_state & I_NEW)) + return inode; + + switch (cramfs_inode->mode & S_IFMT) { + case S_IFREG: + inode->i_fop = &generic_ro_fops; + inode->i_data.a_ops = &cramfs_aops; + break; + case S_IFDIR: + inode->i_op = &cramfs_dir_inode_operations; + inode->i_fop = &cramfs_directory_operations; + break; + case S_IFLNK: + inode->i_op = &page_symlink_inode_operations; + inode->i_data.a_ops = &cramfs_aops; + break; + default: + init_special_inode(inode, cramfs_inode->mode, + old_decode_dev(cramfs_inode->size)); + } + + inode->i_mode = cramfs_inode->mode; + i_uid_write(inode, cramfs_inode->uid); + i_gid_write(inode, cramfs_inode->gid); + + /* if the lower 2 bits are zero, the inode contains data */ + if (!(inode->i_ino & 3)) { inode->i_size = cramfs_inode->size; inode->i_blocks = (cramfs_inode->size - 1) / 512 + 1; - inode->i_gid = cramfs_inode->gid; - /* Struct copy intentional */ - inode->i_mtime = inode->i_atime = inode->i_ctime = zerotime; - /* inode->i_nlink is left 1 - arguably wrong for directories, - but it's the best we can do without reading the directory - contents. 1 yields the right result in GNU find, even - without -noleaf option. */ - if (S_ISREG(inode->i_mode)) { - inode->i_fop = &generic_ro_fops; - inode->i_data.a_ops = &cramfs_aops; - } else if (S_ISDIR(inode->i_mode)) { - inode->i_op = &cramfs_dir_inode_operations; - inode->i_fop = &cramfs_directory_operations; - } else if (S_ISLNK(inode->i_mode)) { - inode->i_op = &page_symlink_inode_operations; - inode->i_data.a_ops = &cramfs_aops; - } else { - init_special_inode(inode, inode->i_mode, - old_decode_dev(cramfs_inode->size)); - } - unlock_new_inode(inode); } - return inode; -} -static void cramfs_drop_inode(struct inode *inode) -{ - if (inode->i_ino == 1) - generic_delete_inode(inode); - else - generic_drop_inode(inode); + /* Struct copy intentional */ + inode->i_mtime = inode->i_atime = inode->i_ctime = zerotime; + /* inode->i_nlink is left 1 - arguably wrong for directories, + but it's the best we can do without reading the directory + contents. 1 yields the right result in GNU find, even + without -noleaf option. */ + + unlock_new_inode(inode); + + return inode; } /* @@ -167,8 +195,7 @@ static void *cramfs_read(struct super_block *sb, unsigned int offset, unsigned i struct page *page = NULL; if (blocknr + i < devsize) { - page = read_mapping_page_async(mapping, blocknr + i, - NULL); + page = read_mapping_page(mapping, blocknr + i, NULL); /* synchronous error? */ if (IS_ERR(page)) page = NULL; @@ -207,14 +234,16 @@ static void *cramfs_read(struct super_block *sb, unsigned int offset, unsigned i return read_buffers[buffer] + offset; } -static void cramfs_put_super(struct super_block *sb) +static void cramfs_kill_sb(struct super_block *sb) { - kfree(sb->s_fs_info); - sb->s_fs_info = NULL; + struct cramfs_sb_info *sbi = CRAMFS_SB(sb); + kill_block_super(sb); + kfree(sbi); } static int cramfs_remount(struct super_block *sb, int *flags, char *data) { + sync_filesystem(sb); *flags |= MS_RDONLY; return 0; } @@ -245,11 +274,11 @@ static int cramfs_fill_super(struct super_block *sb, void *data, int silent) /* Do sanity checks on the superblock */ if (super.magic != CRAMFS_MAGIC) { - /* check for wrong endianess */ + /* check for wrong endianness */ if (super.magic == CRAMFS_MAGIC_WEND) { if (!silent) - printk(KERN_ERR "cramfs: wrong endianess\n"); - goto out; + printk(KERN_ERR "cramfs: wrong endianness\n"); + return -EINVAL; } /* check at 512 byte offset */ @@ -258,24 +287,27 @@ static int cramfs_fill_super(struct super_block *sb, void *data, int silent) mutex_unlock(&read_mutex); if (super.magic != CRAMFS_MAGIC) { if (super.magic == CRAMFS_MAGIC_WEND && !silent) - printk(KERN_ERR "cramfs: wrong endianess\n"); + printk(KERN_ERR "cramfs: wrong endianness\n"); else if (!silent) printk(KERN_ERR "cramfs: wrong magic\n"); - goto out; + return -EINVAL; } } /* get feature flags first */ if (super.flags & ~CRAMFS_SUPPORTED_FLAGS) { printk(KERN_ERR "cramfs: unsupported filesystem features\n"); - goto out; + return -EINVAL; } /* Check that the root inode is in a sane state */ if (!S_ISDIR(super.root.mode)) { printk(KERN_ERR "cramfs: root is not a directory\n"); - goto out; + return -EINVAL; } + /* correct strange, hard-coded permissions of mkcramfs */ + super.root.mode |= (S_IRUSR | S_IXUSR | S_IRGRP | S_IXGRP | S_IROTH | S_IXOTH); + root_offset = super.root.offset << 2; if (super.flags & CRAMFS_FLAG_FSID_VERSION_2) { sbi->size=super.size; @@ -295,24 +327,18 @@ static int cramfs_fill_super(struct super_block *sb, void *data, int silent) (root_offset != 512 + sizeof(struct cramfs_super)))) { printk(KERN_ERR "cramfs: bad root offset %lu\n", root_offset); - goto out; + return -EINVAL; } /* Set it all up.. */ sb->s_op = &cramfs_ops; - root = get_cramfs_inode(sb, &super.root); - if (!root) - goto out; - sb->s_root = d_alloc_root(root); - if (!sb->s_root) { - iput(root); - goto out; - } + root = get_cramfs_inode(sb, &super.root, 0); + if (IS_ERR(root)) + return PTR_ERR(root); + sb->s_root = d_make_root(root); + if (!sb->s_root) + return -ENOMEM; return 0; -out: - kfree(sbi); - sb->s_fs_info = NULL; - return -EINVAL; } static int cramfs_statfs(struct dentry *dentry, struct kstatfs *buf) @@ -336,18 +362,17 @@ static int cramfs_statfs(struct dentry *dentry, struct kstatfs *buf) /* * Read a cramfs directory entry. */ -static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir) +static int cramfs_readdir(struct file *file, struct dir_context *ctx) { - struct inode *inode = filp->f_path.dentry->d_inode; + struct inode *inode = file_inode(file); struct super_block *sb = inode->i_sb; char *buf; unsigned int offset; - int copied; /* Offset within the thing. */ - offset = filp->f_pos; - if (offset >= inode->i_size) + if (ctx->pos >= inode->i_size) return 0; + offset = ctx->pos; /* Directory entries are always 4-byte aligned */ if (offset & 3) return -EINVAL; @@ -356,14 +381,13 @@ static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir) if (!buf) return -ENOMEM; - copied = 0; while (offset < inode->i_size) { struct cramfs_inode *de; unsigned long nextoffset; char *name; ino_t ino; - mode_t mode; - int namelen, error; + umode_t mode; + int namelen; mutex_lock(&read_mutex); de = cramfs_read(sb, OFFSET(inode) + offset, sizeof(*de)+CRAMFS_MAXPATHLEN); @@ -376,7 +400,7 @@ static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir) */ namelen = de->namelen << 2; memcpy(buf, name, namelen); - ino = CRAMINO(de); + ino = cramino(de, OFFSET(inode) + offset); mode = de->mode; mutex_unlock(&read_mutex); nextoffset = offset + sizeof(*de) + namelen; @@ -389,13 +413,10 @@ static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir) break; namelen--; } - error = filldir(dirent, buf, namelen, offset, ino, mode >> 12); - if (error) + if (!dir_emit(ctx, buf, namelen, ino, mode >> 12)) break; - offset = nextoffset; - filp->f_pos = offset; - copied++; + ctx->pos = offset = nextoffset; } kfree(buf); return 0; @@ -404,9 +425,10 @@ static int cramfs_readdir(struct file *filp, void *dirent, filldir_t filldir) /* * Lookup and fill in the inode data.. */ -static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) +static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) { unsigned int offset = 0; + struct inode *inode = NULL; int sorted; mutex_lock(&read_mutex); @@ -415,8 +437,9 @@ static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, s struct cramfs_inode *de; char *name; int namelen, retval; + int dir_off = OFFSET(dir) + offset; - de = cramfs_read(dir->i_sb, OFFSET(dir) + offset, sizeof(*de)+CRAMFS_MAXPATHLEN); + de = cramfs_read(dir->i_sb, dir_off, sizeof(*de)+CRAMFS_MAXPATHLEN); name = (char *)(de+1); /* Try to take advantage of sorted directories */ @@ -432,8 +455,8 @@ static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, s for (;;) { if (!namelen) { - mutex_unlock(&read_mutex); - return ERR_PTR(-EIO); + inode = ERR_PTR(-EIO); + goto out; } if (name[namelen-1]) break; @@ -445,17 +468,18 @@ static struct dentry * cramfs_lookup(struct inode *dir, struct dentry *dentry, s if (retval > 0) continue; if (!retval) { - struct cramfs_inode entry = *de; - mutex_unlock(&read_mutex); - d_add(dentry, get_cramfs_inode(dir->i_sb, &entry)); - return NULL; + inode = get_cramfs_inode(dir->i_sb, de, dir_off); + break; } /* else (retval < 0) */ if (sorted) break; } +out: mutex_unlock(&read_mutex); - d_add(dentry, NULL); + if (IS_ERR(inode)) + return ERR_CAST(inode); + d_add(dentry, inode); return NULL; } @@ -531,7 +555,7 @@ static const struct address_space_operations cramfs_aops = { static const struct file_operations cramfs_directory_operations = { .llseek = generic_file_llseek, .read = generic_read_dir, - .readdir = cramfs_readdir, + .iterate = cramfs_readdir, }; static const struct inode_operations cramfs_dir_inode_operations = { @@ -539,26 +563,24 @@ static const struct inode_operations cramfs_dir_inode_operations = { }; static const struct super_operations cramfs_ops = { - .put_super = cramfs_put_super, .remount_fs = cramfs_remount, .statfs = cramfs_statfs, - .drop_inode = cramfs_drop_inode, }; -static int cramfs_get_sb(struct file_system_type *fs_type, - int flags, const char *dev_name, void *data, struct vfsmount *mnt) +static struct dentry *cramfs_mount(struct file_system_type *fs_type, + int flags, const char *dev_name, void *data) { - return get_sb_bdev(fs_type, flags, dev_name, data, cramfs_fill_super, - mnt); + return mount_bdev(fs_type, flags, dev_name, data, cramfs_fill_super); } static struct file_system_type cramfs_fs_type = { .owner = THIS_MODULE, .name = "cramfs", - .get_sb = cramfs_get_sb, - .kill_sb = kill_block_super, + .mount = cramfs_mount, + .kill_sb = cramfs_kill_sb, .fs_flags = FS_REQUIRES_DEV, }; +MODULE_ALIAS_FS("cramfs"); static int __init init_cramfs_fs(void) { |
