diff options
| -rw-r--r-- | fs/Makefile | 3 | ||||
| -rw-r--r-- | fs/stack.c | 40 | ||||
| -rw-r--r-- | include/linux/fs_stack.h | 31 |
3 files changed, 73 insertions, 1 deletions
diff --git a/fs/Makefile b/fs/Makefile index 9a5ce9323bf..b9ffa63f77f 100644 --- a/fs/Makefile +++ b/fs/Makefile @@ -10,7 +10,8 @@ obj-y := open.o read_write.o file_table.o super.o \ ioctl.o readdir.o select.o fifo.o locks.o dcache.o inode.o \ attr.o bad_inode.o file.o filesystems.o namespace.o aio.o \ seq_file.o xattr.o libfs.o fs-writeback.o \ - pnode.o drop_caches.o splice.o sync.o utimes.o + pnode.o drop_caches.o splice.o sync.o utimes.o \ + stack.o ifeq ($(CONFIG_BLOCK),y) obj-y += buffer.o bio.o block_dev.o direct-io.o mpage.o ioprio.o diff --git a/fs/stack.c b/fs/stack.c new file mode 100644 index 00000000000..5ddbc34535f --- /dev/null +++ b/fs/stack.c @@ -0,0 +1,40 @@ +#include <linux/module.h> +#include <linux/fs.h> +#include <linux/fs_stack.h> + +/* does _NOT_ require i_mutex to be held. + * + * This function cannot be inlined since i_size_{read,write} is rather + * heavy-weight on 32-bit systems + */ +void fsstack_copy_inode_size(struct inode *dst, const struct inode *src) +{ + i_size_write(dst, i_size_read((struct inode *)src)); + dst->i_blocks = src->i_blocks; +} +EXPORT_SYMBOL_GPL(fsstack_copy_inode_size); + +/* copy all attributes; get_nlinks is optional way to override the i_nlink + * copying + */ +void fsstack_copy_attr_all(struct inode *dest, const struct inode *src, + int (*get_nlinks)(struct inode *)) +{ + if (!get_nlinks) + dest->i_nlink = src->i_nlink; + else + dest->i_nlink = (*get_nlinks)(dest); + + dest->i_mode = src->i_mode; + dest->i_uid = src->i_uid; + dest->i_gid = src->i_gid; + dest->i_rdev = src->i_rdev; + dest->i_atime = src->i_atime; + dest->i_mtime = src->i_mtime; + dest->i_ctime = src->i_ctime; + dest->i_blkbits = src->i_blkbits; + dest->i_flags = src->i_flags; + + fsstack_copy_inode_size(dest, src); +} +EXPORT_SYMBOL_GPL(fsstack_copy_attr_all); diff --git a/include/linux/fs_stack.h b/include/linux/fs_stack.h new file mode 100644 index 00000000000..bb516ceeefc --- /dev/null +++ b/include/linux/fs_stack.h @@ -0,0 +1,31 @@ +#ifndef _LINUX_FS_STACK_H +#define _LINUX_FS_STACK_H + +/* This file defines generic functions used primarily by stackable + * filesystems; none of these functions require i_mutex to be held. + */ + +#include <linux/fs.h> + +/* externs for fs/stack.c */ +extern void fsstack_copy_attr_all(struct inode *dest, const struct inode *src, + int (*get_nlinks)(struct inode *)); + +extern void fsstack_copy_inode_size(struct inode *dst, const struct inode *src); + +/* inlines */ +static inline void fsstack_copy_attr_atime(struct inode *dest, + const struct inode *src) +{ + dest->i_atime = src->i_atime; +} + +static inline void fsstack_copy_attr_times(struct inode *dest, + const struct inode *src) +{ + dest->i_atime = src->i_atime; + dest->i_mtime = src->i_mtime; + dest->i_ctime = src->i_ctime; +} + +#endif /* _LINUX_FS_STACK_H */ |