diff options
Diffstat (limited to 'fs/libfs.c')
| -rw-r--r-- | fs/libfs.c | 168 |
1 files changed, 125 insertions, 43 deletions
diff --git a/fs/libfs.c b/fs/libfs.c index 3a3a9b53bf5..88e3e00e2ec 100644 --- a/fs/libfs.c +++ b/fs/libfs.c @@ -3,6 +3,7 @@ * Library for filesystems writers. */ +#include <linux/blkdev.h> #include <linux/export.h> #include <linux/pagemap.h> #include <linux/slab.h> @@ -10,6 +11,7 @@ #include <linux/vfs.h> #include <linux/quotaops.h> #include <linux/mutex.h> +#include <linux/namei.h> #include <linux/exportfs.h> #include <linux/writeback.h> #include <linux/buffer_head.h> /* sync_mapping_buffers */ @@ -31,6 +33,7 @@ int simple_getattr(struct vfsmount *mnt, struct dentry *dentry, stat->blocks = inode->i_mapping->nrpages << (PAGE_CACHE_SHIFT - 9); return 0; } +EXPORT_SYMBOL(simple_getattr); int simple_statfs(struct dentry *dentry, struct kstatfs *buf) { @@ -39,15 +42,22 @@ int simple_statfs(struct dentry *dentry, struct kstatfs *buf) buf->f_namelen = NAME_MAX; return 0; } +EXPORT_SYMBOL(simple_statfs); /* * Retaining negative dentries for an in-memory filesystem just wastes * memory and lookup time: arrange for them to be deleted immediately. */ -static int simple_delete_dentry(const struct dentry *dentry) +int always_delete_dentry(const struct dentry *dentry) { return 1; } +EXPORT_SYMBOL(always_delete_dentry); + +const struct dentry_operations simple_dentry_operations = { + .d_delete = always_delete_dentry, +}; +EXPORT_SYMBOL(simple_dentry_operations); /* * Lookup the data. This is trivial - if the dentry didn't already @@ -55,10 +65,6 @@ static int simple_delete_dentry(const struct dentry *dentry) */ struct dentry *simple_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags) { - static const struct dentry_operations simple_dentry_operations = { - .d_delete = simple_delete_dentry, - }; - if (dentry->d_name.len > NAME_MAX) return ERR_PTR(-ENAMETOOLONG); if (!dentry->d_sb->s_d_op) @@ -66,6 +72,7 @@ struct dentry *simple_lookup(struct inode *dir, struct dentry *dentry, unsigned d_add(dentry, NULL); return NULL; } +EXPORT_SYMBOL(simple_lookup); int dcache_dir_open(struct inode *inode, struct file *file) { @@ -75,12 +82,14 @@ int dcache_dir_open(struct inode *inode, struct file *file) return file->private_data ? 0 : -ENOMEM; } +EXPORT_SYMBOL(dcache_dir_open); int dcache_dir_close(struct inode *inode, struct file *file) { dput(file->private_data); return 0; } +EXPORT_SYMBOL(dcache_dir_close); loff_t dcache_dir_lseek(struct file *file, loff_t offset, int whence) { @@ -123,6 +132,7 @@ loff_t dcache_dir_lseek(struct file *file, loff_t offset, int whence) mutex_unlock(&dentry->d_inode->i_mutex); return offset; } +EXPORT_SYMBOL(dcache_dir_lseek); /* Relationship between i_mode and the DT_xxx types */ static inline unsigned char dt_type(struct inode *inode) @@ -172,11 +182,13 @@ int dcache_readdir(struct file *file, struct dir_context *ctx) spin_unlock(&dentry->d_lock); return 0; } +EXPORT_SYMBOL(dcache_readdir); ssize_t generic_read_dir(struct file *filp, char __user *buf, size_t siz, loff_t *ppos) { return -EISDIR; } +EXPORT_SYMBOL(generic_read_dir); const struct file_operations simple_dir_operations = { .open = dcache_dir_open, @@ -186,10 +198,12 @@ const struct file_operations simple_dir_operations = { .iterate = dcache_readdir, .fsync = noop_fsync, }; +EXPORT_SYMBOL(simple_dir_operations); const struct inode_operations simple_dir_inode_operations = { .lookup = simple_lookup, }; +EXPORT_SYMBOL(simple_dir_inode_operations); static const struct super_operations simple_super_operations = { .statfs = simple_statfs, @@ -244,6 +258,7 @@ Enomem: deactivate_locked_super(s); return ERR_PTR(-ENOMEM); } +EXPORT_SYMBOL(mount_pseudo); int simple_open(struct inode *inode, struct file *file) { @@ -251,6 +266,7 @@ int simple_open(struct inode *inode, struct file *file) file->private_data = inode->i_private; return 0; } +EXPORT_SYMBOL(simple_open); int simple_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry) { @@ -263,6 +279,7 @@ int simple_link(struct dentry *old_dentry, struct inode *dir, struct dentry *den d_instantiate(dentry, inode); return 0; } +EXPORT_SYMBOL(simple_link); int simple_empty(struct dentry *dentry) { @@ -283,6 +300,7 @@ out: spin_unlock(&dentry->d_lock); return ret; } +EXPORT_SYMBOL(simple_empty); int simple_unlink(struct inode *dir, struct dentry *dentry) { @@ -293,6 +311,7 @@ int simple_unlink(struct inode *dir, struct dentry *dentry) dput(dentry); return 0; } +EXPORT_SYMBOL(simple_unlink); int simple_rmdir(struct inode *dir, struct dentry *dentry) { @@ -304,6 +323,7 @@ int simple_rmdir(struct inode *dir, struct dentry *dentry) drop_nlink(dir); return 0; } +EXPORT_SYMBOL(simple_rmdir); int simple_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry) @@ -330,6 +350,7 @@ int simple_rename(struct inode *old_dir, struct dentry *old_dentry, return 0; } +EXPORT_SYMBOL(simple_rename); /** * simple_setattr - setattr for simple filesystem @@ -370,6 +391,7 @@ int simple_readpage(struct file *file, struct page *page) unlock_page(page); return 0; } +EXPORT_SYMBOL(simple_readpage); int simple_write_begin(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned flags, @@ -393,6 +415,7 @@ int simple_write_begin(struct file *file, struct address_space *mapping, } return 0; } +EXPORT_SYMBOL(simple_write_begin); /** * simple_write_end - .write_end helper for non-block-device FSes @@ -444,6 +467,7 @@ int simple_write_end(struct file *file, struct address_space *mapping, return copied; } +EXPORT_SYMBOL(simple_write_end); /* * the inodes created here are not hashed. If you use iunique to generate @@ -512,6 +536,7 @@ out: dput(root); return -ENOMEM; } +EXPORT_SYMBOL(simple_fill_super); static DEFINE_SPINLOCK(pin_fs_lock); @@ -534,6 +559,7 @@ int simple_pin_fs(struct file_system_type *type, struct vfsmount **mount, int *c mntput(mnt); return 0; } +EXPORT_SYMBOL(simple_pin_fs); void simple_release_fs(struct vfsmount **mount, int *count) { @@ -545,6 +571,7 @@ void simple_release_fs(struct vfsmount **mount, int *count) spin_unlock(&pin_fs_lock); mntput(mnt); } +EXPORT_SYMBOL(simple_release_fs); /** * simple_read_from_buffer - copy data from the buffer to user space @@ -579,6 +606,7 @@ ssize_t simple_read_from_buffer(void __user *to, size_t count, loff_t *ppos, *ppos = pos + count; return count; } +EXPORT_SYMBOL(simple_read_from_buffer); /** * simple_write_to_buffer - copy data from user space to the buffer @@ -613,6 +641,7 @@ ssize_t simple_write_to_buffer(void *to, size_t available, loff_t *ppos, *ppos = pos + count; return count; } +EXPORT_SYMBOL(simple_write_to_buffer); /** * memory_read_from_buffer - copy data from the buffer @@ -644,6 +673,7 @@ ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos, return count; } +EXPORT_SYMBOL(memory_read_from_buffer); /* * Transaction based IO. @@ -665,6 +695,7 @@ void simple_transaction_set(struct file *file, size_t n) smp_mb(); ar->size = n; } +EXPORT_SYMBOL(simple_transaction_set); char *simple_transaction_get(struct file *file, const char __user *buf, size_t size) { @@ -696,6 +727,7 @@ char *simple_transaction_get(struct file *file, const char __user *buf, size_t s return ar->data; } +EXPORT_SYMBOL(simple_transaction_get); ssize_t simple_transaction_read(struct file *file, char __user *buf, size_t size, loff_t *pos) { @@ -705,12 +737,14 @@ ssize_t simple_transaction_read(struct file *file, char __user *buf, size_t size return 0; return simple_read_from_buffer(buf, size, pos, ar->data, ar->size); } +EXPORT_SYMBOL(simple_transaction_read); int simple_transaction_release(struct inode *inode, struct file *file) { free_page((unsigned long)file->private_data); return 0; } +EXPORT_SYMBOL(simple_transaction_release); /* Simple attribute files */ @@ -746,12 +780,14 @@ int simple_attr_open(struct inode *inode, struct file *file, return nonseekable_open(inode, file); } +EXPORT_SYMBOL_GPL(simple_attr_open); int simple_attr_release(struct inode *inode, struct file *file) { kfree(file->private_data); return 0; } +EXPORT_SYMBOL_GPL(simple_attr_release); /* GPL-only? This? Really? */ /* read from the buffer that is filled with the get function */ ssize_t simple_attr_read(struct file *file, char __user *buf, @@ -787,6 +823,7 @@ out: mutex_unlock(&attr->mutex); return ret; } +EXPORT_SYMBOL_GPL(simple_attr_read); /* interpret the buffer as a number to call the set function with */ ssize_t simple_attr_write(struct file *file, const char __user *buf, @@ -819,6 +856,7 @@ out: mutex_unlock(&attr->mutex); return ret; } +EXPORT_SYMBOL_GPL(simple_attr_write); /** * generic_fh_to_dentry - generic helper for the fh_to_dentry export operation @@ -886,16 +924,19 @@ struct dentry *generic_fh_to_parent(struct super_block *sb, struct fid *fid, EXPORT_SYMBOL_GPL(generic_fh_to_parent); /** - * generic_file_fsync - generic fsync implementation for simple filesystems + * __generic_file_fsync - generic fsync implementation for simple filesystems + * * @file: file to synchronize + * @start: start offset in bytes + * @end: end offset in bytes (inclusive) * @datasync: only synchronize essential metadata if true * * This is a generic implementation of the fsync method for simple * filesystems which track all non-inode metadata in the buffers list * hanging off the address_space structure. */ -int generic_file_fsync(struct file *file, loff_t start, loff_t end, - int datasync) +int __generic_file_fsync(struct file *file, loff_t start, loff_t end, + int datasync) { struct inode *inode = file->f_mapping->host; int err; @@ -915,10 +956,34 @@ int generic_file_fsync(struct file *file, loff_t start, loff_t end, err = sync_inode_metadata(inode, 1); if (ret == 0) ret = err; + out: mutex_unlock(&inode->i_mutex); return ret; } +EXPORT_SYMBOL(__generic_file_fsync); + +/** + * generic_file_fsync - generic fsync implementation for simple filesystems + * with flush + * @file: file to synchronize + * @start: start offset in bytes + * @end: end offset in bytes (inclusive) + * @datasync: only synchronize essential metadata if true + * + */ + +int generic_file_fsync(struct file *file, loff_t start, loff_t end, + int datasync) +{ + struct inode *inode = file->f_mapping->host; + int err; + + err = __generic_file_fsync(file, start, end, datasync); + if (err) + return err; + return blkdev_issue_flush(inode->i_sb->s_bdev, GFP_KERNEL, NULL); +} EXPORT_SYMBOL(generic_file_fsync); /** @@ -957,39 +1022,56 @@ int noop_fsync(struct file *file, loff_t start, loff_t end, int datasync) { return 0; } - -EXPORT_SYMBOL(dcache_dir_close); -EXPORT_SYMBOL(dcache_dir_lseek); -EXPORT_SYMBOL(dcache_dir_open); -EXPORT_SYMBOL(dcache_readdir); -EXPORT_SYMBOL(generic_read_dir); -EXPORT_SYMBOL(mount_pseudo); -EXPORT_SYMBOL(simple_write_begin); -EXPORT_SYMBOL(simple_write_end); -EXPORT_SYMBOL(simple_dir_inode_operations); -EXPORT_SYMBOL(simple_dir_operations); -EXPORT_SYMBOL(simple_empty); -EXPORT_SYMBOL(simple_fill_super); -EXPORT_SYMBOL(simple_getattr); -EXPORT_SYMBOL(simple_open); -EXPORT_SYMBOL(simple_link); -EXPORT_SYMBOL(simple_lookup); -EXPORT_SYMBOL(simple_pin_fs); -EXPORT_SYMBOL(simple_readpage); -EXPORT_SYMBOL(simple_release_fs); -EXPORT_SYMBOL(simple_rename); -EXPORT_SYMBOL(simple_rmdir); -EXPORT_SYMBOL(simple_statfs); EXPORT_SYMBOL(noop_fsync); -EXPORT_SYMBOL(simple_unlink); -EXPORT_SYMBOL(simple_read_from_buffer); -EXPORT_SYMBOL(simple_write_to_buffer); -EXPORT_SYMBOL(memory_read_from_buffer); -EXPORT_SYMBOL(simple_transaction_set); -EXPORT_SYMBOL(simple_transaction_get); -EXPORT_SYMBOL(simple_transaction_read); -EXPORT_SYMBOL(simple_transaction_release); -EXPORT_SYMBOL_GPL(simple_attr_open); -EXPORT_SYMBOL_GPL(simple_attr_release); -EXPORT_SYMBOL_GPL(simple_attr_read); -EXPORT_SYMBOL_GPL(simple_attr_write); + +void kfree_put_link(struct dentry *dentry, struct nameidata *nd, + void *cookie) +{ + char *s = nd_get_link(nd); + if (!IS_ERR(s)) + kfree(s); +} +EXPORT_SYMBOL(kfree_put_link); + +/* + * nop .set_page_dirty method so that people can use .page_mkwrite on + * anon inodes. + */ +static int anon_set_page_dirty(struct page *page) +{ + return 0; +}; + +/* + * A single inode exists for all anon_inode files. Contrary to pipes, + * anon_inode inodes have no associated per-instance data, so we need + * only allocate one of them. + */ +struct inode *alloc_anon_inode(struct super_block *s) +{ + static const struct address_space_operations anon_aops = { + .set_page_dirty = anon_set_page_dirty, + }; + struct inode *inode = new_inode_pseudo(s); + + if (!inode) + return ERR_PTR(-ENOMEM); + + inode->i_ino = get_next_ino(); + inode->i_mapping->a_ops = &anon_aops; + + /* + * Mark the inode dirty from the very beginning, + * that way it will never be moved to the dirty + * list because mark_inode_dirty() will think + * that it already _is_ on the dirty list. + */ + inode->i_state = I_DIRTY; + inode->i_mode = S_IRUSR | S_IWUSR; + inode->i_uid = current_fsuid(); + inode->i_gid = current_fsgid(); + inode->i_flags |= S_PRIVATE; + inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; + return inode; +} +EXPORT_SYMBOL(alloc_anon_inode); |