Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756266AbXIQS2b (ORCPT ); Mon, 17 Sep 2007 14:28:31 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756066AbXIQS10 (ORCPT ); Mon, 17 Sep 2007 14:27:26 -0400 Received: from e34.co.us.ibm.com ([32.97.110.152]:42214 "EHLO e34.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755965AbXIQS1X (ORCPT ); Mon, 17 Sep 2007 14:27:23 -0400 Subject: [PATCH 01/24] filesystem helpers for custom 'struct file's To: akpm@osdl.org Cc: linux-kernel@vger.kernel.org, hch@infradead.org, Dave Hansen From: Dave Hansen Date: Mon, 17 Sep 2007 11:27:18 -0700 References: <20070917182718.70494C9B@kernel> In-Reply-To: <20070917182718.70494C9B@kernel> Message-Id: <20070917182718.A6B9F7FD@kernel> Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10274 Lines: 303 Christoph H. says this stands on its own and can go in before the rest of the r/o bind mount set. --- Some filesystems forego the vfs and may_open() and create their own 'struct file's. This patch creates a couple of helper functions which can be used by these filesystems, and will provide a unified place which the r/o bind mount code may patch. Also, rename an existing, static-scope init_file() to a less generic name. Signed-off-by: Dave Hansen --- lxc-dave/fs/configfs/dir.c | 5 +++-- lxc-dave/fs/file_table.c | 34 ++++++++++++++++++++++++++++++++++ lxc-dave/fs/hugetlbfs/inode.c | 22 +++++++++------------- lxc-dave/include/linux/file.h | 9 +++++++++ lxc-dave/ipc/shm.c | 13 +++++-------- lxc-dave/mm/shmem.c | 7 ++----- lxc-dave/mm/tiny-shmem.c | 19 +++++++------------ lxc-dave/net/socket.c | 18 +++++++++--------- 8 files changed, 78 insertions(+), 49 deletions(-) diff -puN fs/configfs/dir.c~filesystem-helpers-for-custom-struct-file-s fs/configfs/dir.c --- lxc/fs/configfs/dir.c~filesystem-helpers-for-custom-struct-file-s 2007-09-17 09:43:55.000000000 -0700 +++ lxc-dave/fs/configfs/dir.c 2007-09-17 09:43:55.000000000 -0700 @@ -142,7 +142,7 @@ static int init_dir(struct inode * inode return 0; } -static int init_file(struct inode * inode) +static int configfs_init_file(struct inode * inode) { inode->i_size = PAGE_SIZE; inode->i_fop = &configfs_file_operations; @@ -283,7 +283,8 @@ static int configfs_attach_attr(struct c dentry->d_fsdata = configfs_get(sd); sd->s_dentry = dentry; - error = configfs_create(dentry, (attr->ca_mode & S_IALLUGO) | S_IFREG, init_file); + error = configfs_create(dentry, (attr->ca_mode & S_IALLUGO) | S_IFREG, + configfs_init_file); if (error) { configfs_put(sd); return error; diff -puN fs/file_table.c~filesystem-helpers-for-custom-struct-file-s fs/file_table.c --- lxc/fs/file_table.c~filesystem-helpers-for-custom-struct-file-s 2007-09-17 09:43:55.000000000 -0700 +++ lxc-dave/fs/file_table.c 2007-09-17 09:43:55.000000000 -0700 @@ -137,6 +137,40 @@ fail: EXPORT_SYMBOL(get_empty_filp); +struct file *alloc_file(struct vfsmount *mnt, struct dentry *dentry, + mode_t mode, const struct file_operations *fop) +{ + struct file *file; + struct path; + + file = get_empty_filp(); + if (!file) + return NULL; + + init_file(file, mnt, dentry, mode, fop); + return file; +} +EXPORT_SYMBOL(alloc_file); + +/* + * Note: This is a crappy interface. It is here to make + * merging with the existing users of get_empty_filp() + * who have complex failure logic easier. All users + * of this should be moving to alloc_file(). + */ +int init_file(struct file *file, struct vfsmount *mnt, struct dentry *dentry, + mode_t mode, const struct file_operations *fop) +{ + int error = 0; + file->f_path.dentry = dentry; + file->f_path.mnt = mntget(mnt); + file->f_mapping = dentry->d_inode->i_mapping; + file->f_mode = mode; + file->f_op = fop; + return error; +} +EXPORT_SYMBOL(init_file); + void fastcall fput(struct file *file) { if (atomic_dec_and_test(&file->f_count)) diff -puN fs/hugetlbfs/inode.c~filesystem-helpers-for-custom-struct-file-s fs/hugetlbfs/inode.c --- lxc/fs/hugetlbfs/inode.c~filesystem-helpers-for-custom-struct-file-s 2007-09-17 09:43:55.000000000 -0700 +++ lxc-dave/fs/hugetlbfs/inode.c 2007-09-17 09:43:55.000000000 -0700 @@ -923,16 +923,11 @@ struct file *hugetlb_file_setup(const ch if (!dentry) goto out_shm_unlock; - error = -ENFILE; - file = get_empty_filp(); - if (!file) - goto out_dentry; - error = -ENOSPC; inode = hugetlbfs_get_inode(root->d_sb, current->fsuid, current->fsgid, S_IFREG | S_IRWXUGO, 0); if (!inode) - goto out_file; + goto out_dentry; error = -ENOMEM; if (hugetlb_reserve_pages(inode, 0, size >> HPAGE_SHIFT)) @@ -941,17 +936,18 @@ struct file *hugetlb_file_setup(const ch d_instantiate(dentry, inode); inode->i_size = size; inode->i_nlink = 0; - file->f_path.mnt = mntget(hugetlbfs_vfsmount); - file->f_path.dentry = dentry; - file->f_mapping = inode->i_mapping; - file->f_op = &hugetlbfs_file_operations; - file->f_mode = FMODE_WRITE | FMODE_READ; + + error = -ENFILE; + file = alloc_file(hugetlbfs_vfsmount, dentry, + FMODE_WRITE | FMODE_READ, + &hugetlbfs_file_operations); + if (!file) + goto out_inode; + return file; out_inode: iput(inode); -out_file: - put_filp(file); out_dentry: dput(dentry); out_shm_unlock: diff -puN include/linux/file.h~filesystem-helpers-for-custom-struct-file-s include/linux/file.h --- lxc/include/linux/file.h~filesystem-helpers-for-custom-struct-file-s 2007-09-17 09:43:55.000000000 -0700 +++ lxc-dave/include/linux/file.h 2007-09-17 09:43:55.000000000 -0700 @@ -62,6 +62,15 @@ extern struct kmem_cache *filp_cachep; extern void FASTCALL(__fput(struct file *)); extern void FASTCALL(fput(struct file *)); +struct file_operations; +struct vfsmount; +struct dentry; +extern int init_file(struct file *, struct vfsmount *mnt, + struct dentry *dentry, mode_t mode, + const struct file_operations *fop); +extern struct file *alloc_file(struct vfsmount *, struct dentry *dentry, + mode_t mode, const struct file_operations *fop); + static inline void fput_light(struct file *file, int fput_needed) { if (unlikely(fput_needed)) diff -puN ipc/shm.c~filesystem-helpers-for-custom-struct-file-s ipc/shm.c --- lxc/ipc/shm.c~filesystem-helpers-for-custom-struct-file-s 2007-09-17 09:43:55.000000000 -0700 +++ lxc-dave/ipc/shm.c 2007-09-17 09:43:55.000000000 -0700 @@ -907,7 +907,7 @@ long do_shmat(int shmid, char __user *sh goto out_unlock; path.dentry = dget(shp->shm_file->f_path.dentry); - path.mnt = mntget(shp->shm_file->f_path.mnt); + path.mnt = shp->shm_file->f_path.mnt; shp->shm_nattch++; size = i_size_read(path.dentry->d_inode); shm_unlock(shp); @@ -915,18 +915,16 @@ long do_shmat(int shmid, char __user *sh err = -ENOMEM; sfd = kzalloc(sizeof(*sfd), GFP_KERNEL); if (!sfd) - goto out_put_path; + goto out_put_dentry; err = -ENOMEM; - file = get_empty_filp(); + + file = alloc_file(path.mnt, path.dentry, f_mode, &shm_file_operations); if (!file) goto out_free; - file->f_op = &shm_file_operations; file->private_data = sfd; - file->f_path = path; file->f_mapping = shp->shm_file->f_mapping; - file->f_mode = f_mode; sfd->id = shp->id; sfd->ns = get_ipc_ns(ns); sfd->file = shp->shm_file; @@ -977,9 +975,8 @@ out_unlock: out_free: kfree(sfd); -out_put_path: +out_put_dentry: dput(path.dentry); - mntput(path.mnt); goto out_nattch; } diff -puN mm/shmem.c~filesystem-helpers-for-custom-struct-file-s mm/shmem.c --- lxc/mm/shmem.c~filesystem-helpers-for-custom-struct-file-s 2007-09-17 09:43:55.000000000 -0700 +++ lxc-dave/mm/shmem.c 2007-09-17 09:43:55.000000000 -0700 @@ -2538,11 +2538,8 @@ struct file *shmem_file_setup(char *name d_instantiate(dentry, inode); inode->i_size = size; inode->i_nlink = 0; /* It is unlinked */ - file->f_path.mnt = mntget(shm_mnt); - file->f_path.dentry = dentry; - file->f_mapping = inode->i_mapping; - file->f_op = &shmem_file_operations; - file->f_mode = FMODE_WRITE | FMODE_READ; + init_file(file, shm_mnt, dentry, FMODE_WRITE | FMODE_READ, + &shmem_file_operations); return file; close_file: diff -puN mm/tiny-shmem.c~filesystem-helpers-for-custom-struct-file-s mm/tiny-shmem.c --- lxc/mm/tiny-shmem.c~filesystem-helpers-for-custom-struct-file-s 2007-09-17 09:43:55.000000000 -0700 +++ lxc-dave/mm/tiny-shmem.c 2007-09-17 09:43:55.000000000 -0700 @@ -66,24 +66,19 @@ struct file *shmem_file_setup(char *name if (!dentry) goto put_memory; - error = -ENFILE; - file = get_empty_filp(); - if (!file) - goto put_dentry; - error = -ENOSPC; inode = ramfs_get_inode(root->d_sb, S_IFREG | S_IRWXUGO, 0); if (!inode) - goto close_file; + goto put_dentry; d_instantiate(dentry, inode); - inode->i_nlink = 0; /* It is unlinked */ + error = -ENFILE; + file = alloc_file(shm_mnt, dentry, FMODE_WRITE | FMODE_READ, + &ramfs_file_operations); + if (!file) + goto put_dentry; - file->f_path.mnt = mntget(shm_mnt); - file->f_path.dentry = dentry; - file->f_mapping = inode->i_mapping; - file->f_op = &ramfs_file_operations; - file->f_mode = FMODE_WRITE | FMODE_READ; + inode->i_nlink = 0; /* It is unlinked */ /* notify everyone as to the change of file size */ error = do_truncate(dentry, size, 0, file); diff -puN net/socket.c~filesystem-helpers-for-custom-struct-file-s net/socket.c --- lxc/net/socket.c~filesystem-helpers-for-custom-struct-file-s 2007-09-17 09:43:55.000000000 -0700 +++ lxc-dave/net/socket.c 2007-09-17 09:43:55.000000000 -0700 @@ -367,26 +367,26 @@ static int sock_alloc_fd(struct file **f static int sock_attach_fd(struct socket *sock, struct file *file) { + struct dentry *dentry; struct qstr name = { .name = "" }; - file->f_path.dentry = d_alloc(sock_mnt->mnt_sb->s_root, &name); - if (unlikely(!file->f_path.dentry)) + dentry = d_alloc(sock_mnt->mnt_sb->s_root, &name); + if (unlikely(!dentry)) return -ENOMEM; - file->f_path.dentry->d_op = &sockfs_dentry_operations; + dentry->d_op = &sockfs_dentry_operations; /* * We dont want to push this dentry into global dentry hash table. * We pretend dentry is already hashed, by unsetting DCACHE_UNHASHED * This permits a working /proc/$pid/fd/XXX on sockets */ - file->f_path.dentry->d_flags &= ~DCACHE_UNHASHED; - d_instantiate(file->f_path.dentry, SOCK_INODE(sock)); - file->f_path.mnt = mntget(sock_mnt); - file->f_mapping = file->f_path.dentry->d_inode->i_mapping; + dentry->d_flags &= ~DCACHE_UNHASHED; + d_instantiate(dentry, SOCK_INODE(sock)); sock->file = file; - file->f_op = SOCK_INODE(sock)->i_fop = &socket_file_ops; - file->f_mode = FMODE_READ | FMODE_WRITE; + init_file(file, sock_mnt, dentry, FMODE_READ | FMODE_WRITE, + &socket_file_ops); + SOCK_INODE(sock)->i_fop = &socket_file_ops; file->f_flags = O_RDWR; file->f_pos = 0; file->private_data = sock; _ - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/