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fs/libfs.c
21.1 KB
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/* * fs/libfs.c * Library for filesystems writers. */ #include <linux/module.h> #include <linux/pagemap.h> #include <linux/mount.h> #include <linux/vfs.h> |
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#include <linux/mutex.h> |
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#include <linux/exportfs.h> |
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#include <asm/uaccess.h> int simple_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat) { struct inode *inode = dentry->d_inode; generic_fillattr(inode, stat); stat->blocks = inode->i_mapping->nrpages << (PAGE_CACHE_SHIFT - 9); return 0; } |
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int simple_statfs(struct dentry *dentry, struct kstatfs *buf) |
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{ |
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buf->f_type = dentry->d_sb->s_magic; |
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buf->f_bsize = PAGE_CACHE_SIZE; buf->f_namelen = NAME_MAX; return 0; } /* * 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(struct dentry *dentry) { return 1; } /* * Lookup the data. This is trivial - if the dentry didn't already * exist, we know it is negative. Set d_op to delete negative dentries. */ struct dentry *simple_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd) { static struct dentry_operations simple_dentry_operations = { .d_delete = simple_delete_dentry, }; if (dentry->d_name.len > NAME_MAX) return ERR_PTR(-ENAMETOOLONG); dentry->d_op = &simple_dentry_operations; d_add(dentry, NULL); return NULL; } int simple_sync_file(struct file * file, struct dentry *dentry, int datasync) { return 0; } int dcache_dir_open(struct inode *inode, struct file *file) { static struct qstr cursor_name = {.len = 1, .name = "."}; |
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file->private_data = d_alloc(file->f_path.dentry, &cursor_name); |
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return file->private_data ? 0 : -ENOMEM; } int dcache_dir_close(struct inode *inode, struct file *file) { dput(file->private_data); return 0; } loff_t dcache_dir_lseek(struct file *file, loff_t offset, int origin) { |
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mutex_lock(&file->f_path.dentry->d_inode->i_mutex); |
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switch (origin) { case 1: offset += file->f_pos; case 0: if (offset >= 0) break; default: |
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mutex_unlock(&file->f_path.dentry->d_inode->i_mutex); |
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return -EINVAL; } if (offset != file->f_pos) { file->f_pos = offset; if (file->f_pos >= 2) { struct list_head *p; struct dentry *cursor = file->private_data; loff_t n = file->f_pos - 2; spin_lock(&dcache_lock); |
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list_del(&cursor->d_u.d_child); |
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p = file->f_path.dentry->d_subdirs.next; while (n && p != &file->f_path.dentry->d_subdirs) { |
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struct dentry *next; |
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next = list_entry(p, struct dentry, d_u.d_child); |
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if (!d_unhashed(next) && next->d_inode) n--; p = p->next; } |
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list_add_tail(&cursor->d_u.d_child, p); |
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spin_unlock(&dcache_lock); } } |
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mutex_unlock(&file->f_path.dentry->d_inode->i_mutex); |
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return offset; } /* Relationship between i_mode and the DT_xxx types */ static inline unsigned char dt_type(struct inode *inode) { return (inode->i_mode >> 12) & 15; } /* * Directory is locked and all positive dentries in it are safe, since * for ramfs-type trees they can't go away without unlink() or rmdir(), * both impossible due to the lock on directory. */ int dcache_readdir(struct file * filp, void * dirent, filldir_t filldir) { |
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struct dentry *dentry = filp->f_path.dentry; |
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struct dentry *cursor = filp->private_data; |
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struct list_head *p, *q = &cursor->d_u.d_child; |
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ino_t ino; int i = filp->f_pos; switch (i) { case 0: ino = dentry->d_inode->i_ino; if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) break; filp->f_pos++; i++; /* fallthrough */ case 1: ino = parent_ino(dentry); if (filldir(dirent, "..", 2, i, ino, DT_DIR) < 0) break; filp->f_pos++; i++; /* fallthrough */ default: spin_lock(&dcache_lock); |
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if (filp->f_pos == 2) list_move(q, &dentry->d_subdirs); |
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for (p=q->next; p != &dentry->d_subdirs; p=p->next) { struct dentry *next; |
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next = list_entry(p, struct dentry, d_u.d_child); |
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if (d_unhashed(next) || !next->d_inode) continue; spin_unlock(&dcache_lock); |
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if (filldir(dirent, next->d_name.name, next->d_name.len, filp->f_pos, next->d_inode->i_ino, dt_type(next->d_inode)) < 0) |
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return 0; spin_lock(&dcache_lock); /* next is still alive */ |
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list_move(q, p); |
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p = q; filp->f_pos++; } spin_unlock(&dcache_lock); } return 0; } ssize_t generic_read_dir(struct file *filp, char __user *buf, size_t siz, loff_t *ppos) { return -EISDIR; } |
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const struct file_operations simple_dir_operations = { |
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.open = dcache_dir_open, .release = dcache_dir_close, .llseek = dcache_dir_lseek, .read = generic_read_dir, .readdir = dcache_readdir, |
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.fsync = simple_sync_file, |
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}; |
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const struct inode_operations simple_dir_inode_operations = { |
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.lookup = simple_lookup, }; |
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static const struct super_operations simple_super_operations = { .statfs = simple_statfs, }; |
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/* * Common helper for pseudo-filesystems (sockfs, pipefs, bdev - stuff that * will never be mountable) */ |
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int get_sb_pseudo(struct file_system_type *fs_type, char *name, |
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const struct super_operations *ops, unsigned long magic, |
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struct vfsmount *mnt) |
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{ struct super_block *s = sget(fs_type, NULL, set_anon_super, NULL); |
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struct dentry *dentry; struct inode *root; struct qstr d_name = {.name = name, .len = strlen(name)}; if (IS_ERR(s)) |
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return PTR_ERR(s); |
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s->s_flags = MS_NOUSER; s->s_maxbytes = ~0ULL; |
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s->s_blocksize = PAGE_SIZE; s->s_blocksize_bits = PAGE_SHIFT; |
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s->s_magic = magic; |
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s->s_op = ops ? ops : &simple_super_operations; |
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s->s_time_gran = 1; root = new_inode(s); if (!root) goto Enomem; |
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/* * since this is the first inode, make it number 1. New inodes created * after this must take care not to collide with it (by passing * max_reserved of 1 to iunique). */ root->i_ino = 1; |
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root->i_mode = S_IFDIR | S_IRUSR | S_IWUSR; root->i_uid = root->i_gid = 0; root->i_atime = root->i_mtime = root->i_ctime = CURRENT_TIME; dentry = d_alloc(NULL, &d_name); if (!dentry) { iput(root); goto Enomem; } dentry->d_sb = s; dentry->d_parent = dentry; d_instantiate(dentry, root); s->s_root = dentry; s->s_flags |= MS_ACTIVE; |
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return simple_set_mnt(mnt, s); |
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Enomem: up_write(&s->s_umount); deactivate_super(s); |
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return -ENOMEM; |
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} int simple_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry) { struct inode *inode = old_dentry->d_inode; inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME; |
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inc_nlink(inode); |
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atomic_inc(&inode->i_count); dget(dentry); d_instantiate(dentry, inode); return 0; } static inline int simple_positive(struct dentry *dentry) { return dentry->d_inode && !d_unhashed(dentry); } int simple_empty(struct dentry *dentry) { struct dentry *child; int ret = 0; spin_lock(&dcache_lock); |
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list_for_each_entry(child, &dentry->d_subdirs, d_u.d_child) |
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if (simple_positive(child)) goto out; ret = 1; out: spin_unlock(&dcache_lock); return ret; } int simple_unlink(struct inode *dir, struct dentry *dentry) { struct inode *inode = dentry->d_inode; inode->i_ctime = dir->i_ctime = dir->i_mtime = CURRENT_TIME; |
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drop_nlink(inode); |
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dput(dentry); return 0; } int simple_rmdir(struct inode *dir, struct dentry *dentry) { if (!simple_empty(dentry)) return -ENOTEMPTY; |
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drop_nlink(dentry->d_inode); |
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simple_unlink(dir, dentry); |
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drop_nlink(dir); |
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return 0; } int simple_rename(struct inode *old_dir, struct dentry *old_dentry, struct inode *new_dir, struct dentry *new_dentry) { struct inode *inode = old_dentry->d_inode; int they_are_dirs = S_ISDIR(old_dentry->d_inode->i_mode); if (!simple_empty(new_dentry)) return -ENOTEMPTY; if (new_dentry->d_inode) { simple_unlink(new_dir, new_dentry); if (they_are_dirs) |
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drop_nlink(old_dir); |
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} else if (they_are_dirs) { |
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drop_nlink(old_dir); |
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inc_nlink(new_dir); |
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} old_dir->i_ctime = old_dir->i_mtime = new_dir->i_ctime = new_dir->i_mtime = inode->i_ctime = CURRENT_TIME; return 0; } int simple_readpage(struct file *file, struct page *page) { |
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clear_highpage(page); |
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flush_dcache_page(page); SetPageUptodate(page); |
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unlock_page(page); return 0; } int simple_prepare_write(struct file *file, struct page *page, unsigned from, unsigned to) { if (!PageUptodate(page)) { |
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if (to - from != PAGE_CACHE_SIZE) zero_user_segments(page, 0, from, to, PAGE_CACHE_SIZE); |
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} return 0; } |
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int simple_write_begin(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned flags, struct page **pagep, void **fsdata) { struct page *page; pgoff_t index; unsigned from; index = pos >> PAGE_CACHE_SHIFT; from = pos & (PAGE_CACHE_SIZE - 1); page = __grab_cache_page(mapping, index); if (!page) return -ENOMEM; *pagep = page; return simple_prepare_write(file, page, from, from+len); } |
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static int simple_commit_write(struct file *file, struct page *page, unsigned from, unsigned to) |
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{ struct inode *inode = page->mapping->host; loff_t pos = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to; |
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if (!PageUptodate(page)) SetPageUptodate(page); |
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/* * No need to use i_size_read() here, the i_size |
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* cannot change under us because we hold the i_mutex. |
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*/ if (pos > inode->i_size) i_size_write(inode, pos); set_page_dirty(page); return 0; } |
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int simple_write_end(struct file *file, struct address_space *mapping, loff_t pos, unsigned len, unsigned copied, struct page *page, void *fsdata) { unsigned from = pos & (PAGE_CACHE_SIZE - 1); /* zero the stale part of the page if we did a short copy */ if (copied < len) { void *kaddr = kmap_atomic(page, KM_USER0); memset(kaddr + from + copied, 0, len - copied); flush_dcache_page(page); kunmap_atomic(kaddr, KM_USER0); } simple_commit_write(file, page, from, from+copied); unlock_page(page); page_cache_release(page); return copied; } |
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/* * the inodes created here are not hashed. If you use iunique to generate * unique inode values later for this filesystem, then you must take care * to pass it an appropriate max_reserved value to avoid collisions. */ |
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int simple_fill_super(struct super_block *s, int magic, struct tree_descr *files) { |
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struct inode *inode; struct dentry *root; struct dentry *dentry; int i; s->s_blocksize = PAGE_CACHE_SIZE; s->s_blocksize_bits = PAGE_CACHE_SHIFT; s->s_magic = magic; |
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s->s_op = &simple_super_operations; |
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s->s_time_gran = 1; inode = new_inode(s); if (!inode) return -ENOMEM; |
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/* * because the root inode is 1, the files array must not contain an * entry at index 1 */ inode->i_ino = 1; |
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inode->i_mode = S_IFDIR | 0755; inode->i_uid = inode->i_gid = 0; |
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inode->i_blocks = 0; inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; inode->i_op = &simple_dir_inode_operations; inode->i_fop = &simple_dir_operations; |
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inode->i_nlink = 2; |
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root = d_alloc_root(inode); if (!root) { iput(inode); return -ENOMEM; } for (i = 0; !files->name || files->name[0]; i++, files++) { if (!files->name) continue; |
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/* warn if it tries to conflict with the root inode */ if (unlikely(i == 1)) printk(KERN_WARNING "%s: %s passed in a files array" "with an index of 1! ", __func__, s->s_type->name); |
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dentry = d_alloc_name(root, files->name); if (!dentry) goto out; inode = new_inode(s); if (!inode) goto out; inode->i_mode = S_IFREG | files->mode; inode->i_uid = inode->i_gid = 0; |
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inode->i_blocks = 0; inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; inode->i_fop = files->ops; inode->i_ino = i; d_add(dentry, inode); } s->s_root = root; return 0; out: d_genocide(root); dput(root); return -ENOMEM; } static DEFINE_SPINLOCK(pin_fs_lock); |
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int simple_pin_fs(struct file_system_type *type, struct vfsmount **mount, int *count) |
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{ struct vfsmount *mnt = NULL; spin_lock(&pin_fs_lock); if (unlikely(!*mount)) { spin_unlock(&pin_fs_lock); |
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mnt = vfs_kern_mount(type, 0, type->name, NULL); |
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if (IS_ERR(mnt)) return PTR_ERR(mnt); spin_lock(&pin_fs_lock); if (!*mount) *mount = mnt; } mntget(*mount); ++*count; spin_unlock(&pin_fs_lock); mntput(mnt); return 0; } void simple_release_fs(struct vfsmount **mount, int *count) { struct vfsmount *mnt; spin_lock(&pin_fs_lock); mnt = *mount; if (!--*count) *mount = NULL; spin_unlock(&pin_fs_lock); mntput(mnt); } |
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/** * simple_read_from_buffer - copy data from the buffer to user space * @to: the user space buffer to read to * @count: the maximum number of bytes to read * @ppos: the current position in the buffer * @from: the buffer to read from * @available: the size of the buffer * * The simple_read_from_buffer() function reads up to @count bytes from the * buffer @from at offset @ppos into the user space address starting at @to. * * On success, the number of bytes read is returned and the offset @ppos is * advanced by this number, or negative value is returned on error. **/ |
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ssize_t simple_read_from_buffer(void __user *to, size_t count, loff_t *ppos, const void *from, size_t available) { loff_t pos = *ppos; if (pos < 0) return -EINVAL; if (pos >= available) return 0; if (count > available - pos) count = available - pos; if (copy_to_user(to, from + pos, count)) return -EFAULT; *ppos = pos + count; return count; } |
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/** * memory_read_from_buffer - copy data from the buffer * @to: the kernel space buffer to read to * @count: the maximum number of bytes to read * @ppos: the current position in the buffer * @from: the buffer to read from * @available: the size of the buffer * * The memory_read_from_buffer() function reads up to @count bytes from the * buffer @from at offset @ppos into the kernel space address starting at @to. * * On success, the number of bytes read is returned and the offset @ppos is * advanced by this number, or negative value is returned on error. **/ |
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ssize_t memory_read_from_buffer(void *to, size_t count, loff_t *ppos, const void *from, size_t available) { loff_t pos = *ppos; if (pos < 0) return -EINVAL; if (pos >= available) return 0; if (count > available - pos) count = available - pos; memcpy(to, from + pos, count); *ppos = pos + count; return count; } |
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/* * Transaction based IO. * The file expects a single write which triggers the transaction, and then * possibly a read which collects the result - which is stored in a * file-local buffer. */ char *simple_transaction_get(struct file *file, const char __user *buf, size_t size) { struct simple_transaction_argresp *ar; static DEFINE_SPINLOCK(simple_transaction_lock); if (size > SIMPLE_TRANSACTION_LIMIT - 1) return ERR_PTR(-EFBIG); ar = (struct simple_transaction_argresp *)get_zeroed_page(GFP_KERNEL); if (!ar) return ERR_PTR(-ENOMEM); spin_lock(&simple_transaction_lock); /* only one write allowed per open */ if (file->private_data) { spin_unlock(&simple_transaction_lock); free_page((unsigned long)ar); return ERR_PTR(-EBUSY); } file->private_data = ar; spin_unlock(&simple_transaction_lock); if (copy_from_user(ar->data, buf, size)) return ERR_PTR(-EFAULT); return ar->data; } ssize_t simple_transaction_read(struct file *file, char __user *buf, size_t size, loff_t *pos) { struct simple_transaction_argresp *ar = file->private_data; if (!ar) return 0; return simple_read_from_buffer(buf, size, pos, ar->data, ar->size); } int simple_transaction_release(struct inode *inode, struct file *file) { free_page((unsigned long)file->private_data); return 0; } |
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/* Simple attribute files */ struct simple_attr { |
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int (*get)(void *, u64 *); int (*set)(void *, u64); |
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char get_buf[24]; /* enough to store a u64 and " \0" */ char set_buf[24]; void *data; const char *fmt; /* format for read operation */ |
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struct mutex mutex; /* protects access to these buffers */ |
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}; /* simple_attr_open is called by an actual attribute open file operation * to set the attribute specific access operations. */ int simple_attr_open(struct inode *inode, struct file *file, |
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int (*get)(void *, u64 *), int (*set)(void *, u64), |
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const char *fmt) { struct simple_attr *attr; attr = kmalloc(sizeof(*attr), GFP_KERNEL); if (!attr) return -ENOMEM; attr->get = get; attr->set = set; |
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attr->data = inode->i_private; |
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attr->fmt = fmt; |
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mutex_init(&attr->mutex); |
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file->private_data = attr; return nonseekable_open(inode, file); } |
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int simple_attr_release(struct inode *inode, struct file *file) |
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{ kfree(file->private_data); return 0; } /* read from the buffer that is filled with the get function */ ssize_t simple_attr_read(struct file *file, char __user *buf, size_t len, loff_t *ppos) { struct simple_attr *attr; size_t size; ssize_t ret; attr = file->private_data; if (!attr->get) return -EACCES; |
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ret = mutex_lock_interruptible(&attr->mutex); if (ret) return ret; |
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666 |
if (*ppos) { /* continued read */ |
acaefc25d
|
667 |
size = strlen(attr->get_buf); |
8b88b0998
|
668 669 670 671 672 |
} else { /* first read */ u64 val; ret = attr->get(attr->data, &val); if (ret) goto out; |
acaefc25d
|
673 |
size = scnprintf(attr->get_buf, sizeof(attr->get_buf), |
8b88b0998
|
674 675 |
attr->fmt, (unsigned long long)val); } |
acaefc25d
|
676 677 |
ret = simple_read_from_buffer(buf, len, ppos, attr->get_buf, size); |
8b88b0998
|
678 |
out: |
7cf34c761
|
679 |
mutex_unlock(&attr->mutex); |
acaefc25d
|
680 681 682 683 684 685 686 687 688 689 690 691 692 |
return ret; } /* interpret the buffer as a number to call the set function with */ ssize_t simple_attr_write(struct file *file, const char __user *buf, size_t len, loff_t *ppos) { struct simple_attr *attr; u64 val; size_t size; ssize_t ret; attr = file->private_data; |
acaefc25d
|
693 694 |
if (!attr->set) return -EACCES; |
9261303ab
|
695 696 697 |
ret = mutex_lock_interruptible(&attr->mutex); if (ret) return ret; |
acaefc25d
|
698 699 700 701 702 703 704 705 706 707 |
ret = -EFAULT; size = min(sizeof(attr->set_buf) - 1, len); if (copy_from_user(attr->set_buf, buf, size)) goto out; ret = len; /* claim we got the whole input */ attr->set_buf[size] = '\0'; val = simple_strtol(attr->set_buf, NULL, 0); attr->set(attr->data, val); out: |
7cf34c761
|
708 |
mutex_unlock(&attr->mutex); |
acaefc25d
|
709 710 |
return ret; } |
2596110a3
|
711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 |
/* * This is what d_alloc_anon should have been. Once the exportfs * argument transition has been finished I will update d_alloc_anon * to this prototype and this wrapper will go away. --hch */ static struct dentry *exportfs_d_alloc(struct inode *inode) { struct dentry *dentry; if (!inode) return NULL; if (IS_ERR(inode)) return ERR_PTR(PTR_ERR(inode)); dentry = d_alloc_anon(inode); if (!dentry) { iput(inode); dentry = ERR_PTR(-ENOMEM); } return dentry; } /** * generic_fh_to_dentry - generic helper for the fh_to_dentry export operation * @sb: filesystem to do the file handle conversion on * @fid: file handle to convert * @fh_len: length of the file handle in bytes * @fh_type: type of file handle * @get_inode: filesystem callback to retrieve inode * * This function decodes @fid as long as it has one of the well-known * Linux filehandle types and calls @get_inode on it to retrieve the * inode for the object specified in the file handle. */ struct dentry *generic_fh_to_dentry(struct super_block *sb, struct fid *fid, int fh_len, int fh_type, struct inode *(*get_inode) (struct super_block *sb, u64 ino, u32 gen)) { struct inode *inode = NULL; if (fh_len < 2) return NULL; switch (fh_type) { case FILEID_INO32_GEN: case FILEID_INO32_GEN_PARENT: inode = get_inode(sb, fid->i32.ino, fid->i32.gen); break; } return exportfs_d_alloc(inode); } EXPORT_SYMBOL_GPL(generic_fh_to_dentry); /** * generic_fh_to_dentry - generic helper for the fh_to_parent export operation * @sb: filesystem to do the file handle conversion on * @fid: file handle to convert * @fh_len: length of the file handle in bytes * @fh_type: type of file handle * @get_inode: filesystem callback to retrieve inode * * This function decodes @fid as long as it has one of the well-known * Linux filehandle types and calls @get_inode on it to retrieve the * inode for the _parent_ object specified in the file handle if it * is specified in the file handle, or NULL otherwise. */ struct dentry *generic_fh_to_parent(struct super_block *sb, struct fid *fid, int fh_len, int fh_type, struct inode *(*get_inode) (struct super_block *sb, u64 ino, u32 gen)) { struct inode *inode = NULL; if (fh_len <= 2) return NULL; switch (fh_type) { case FILEID_INO32_GEN_PARENT: inode = get_inode(sb, fid->i32.parent_ino, (fh_len > 3 ? fid->i32.parent_gen : 0)); break; } return exportfs_d_alloc(inode); } EXPORT_SYMBOL_GPL(generic_fh_to_parent); |
1da177e4c
|
797 798 799 800 801 802 |
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(get_sb_pseudo); |
afddba49d
|
803 804 |
EXPORT_SYMBOL(simple_write_begin); EXPORT_SYMBOL(simple_write_end); |
1da177e4c
|
805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 |
EXPORT_SYMBOL(simple_dir_inode_operations); EXPORT_SYMBOL(simple_dir_operations); EXPORT_SYMBOL(simple_empty); EXPORT_SYMBOL(d_alloc_name); EXPORT_SYMBOL(simple_fill_super); EXPORT_SYMBOL(simple_getattr); EXPORT_SYMBOL(simple_link); EXPORT_SYMBOL(simple_lookup); EXPORT_SYMBOL(simple_pin_fs); EXPORT_SYMBOL(simple_prepare_write); EXPORT_SYMBOL(simple_readpage); EXPORT_SYMBOL(simple_release_fs); EXPORT_SYMBOL(simple_rename); EXPORT_SYMBOL(simple_rmdir); EXPORT_SYMBOL(simple_statfs); EXPORT_SYMBOL(simple_sync_file); EXPORT_SYMBOL(simple_unlink); EXPORT_SYMBOL(simple_read_from_buffer); |
93b071139
|
823 |
EXPORT_SYMBOL(memory_read_from_buffer); |
1da177e4c
|
824 825 826 |
EXPORT_SYMBOL(simple_transaction_get); EXPORT_SYMBOL(simple_transaction_read); EXPORT_SYMBOL(simple_transaction_release); |
acaefc25d
|
827 |
EXPORT_SYMBOL_GPL(simple_attr_open); |
74bedc4d5
|
828 |
EXPORT_SYMBOL_GPL(simple_attr_release); |
acaefc25d
|
829 830 |
EXPORT_SYMBOL_GPL(simple_attr_read); EXPORT_SYMBOL_GPL(simple_attr_write); |