From: Eric Sandeen <sandeen@redhat.com> Date: Tue, 18 Dec 2007 12:06:24 -0600 Subject: [fs] ecryptfs: stacking functions from upstream vfs Message-id: 47680C20.9010202@redhat.com O-Subject: [RHEL 5.2 PATCH] 2/15: stacking filesystem functions from upstream vfs Bugzilla: 228341 Filesystem stacking code from upstream (2.6.24-rc4) fs/Makefile | 3 ++- fs/stack.c | 42 ++++++++++++++++++++++++++++++++++++++++++ include/linux/fs_stack.h | 31 +++++++++++++++++++++++++++++++ 3 files changed, 75 insertions(+), 1 deletion(-) diff --git a/fs/Makefile b/fs/Makefile index 10b629b..e6b3fc3 100644 --- a/fs/Makefile +++ b/fs/Makefile @@ -10,7 +10,8 @@ obj-y := open.o read_write.o file_table.o buffer.o bio.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 mpage.o direct-io.o \ - ioprio.o pnode.o drop_caches.o splice.o sync.o + ioprio.o pnode.o drop_caches.o splice.o sync.o \ + stack.o obj-$(CONFIG_INOTIFY) += inotify.o obj-$(CONFIG_INOTIFY_USER) += inotify_user.o diff --git a/fs/stack.c b/fs/stack.c new file mode 100644 index 0000000..67716f6 --- /dev/null +++ b/fs/stack.c @@ -0,0 +1,42 @@ +#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 *)) +{ + 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; + + /* + * Update the nlinks AFTER updating the above fields, because the + * get_links callback may depend on them. + */ + if (!get_nlinks) + dest->i_nlink = src->i_nlink; + else + dest->i_nlink = (*get_nlinks)(dest); +} +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 0000000..bb516ce --- /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 */