| Message ID | 20191002075714.19495-1-christian.brauner@ubuntu.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v1,SRU,EOAN] UBUNTU: SAUCE: shiftfs: rework how shiftfs opens files | expand |
On Wed, Oct 02, 2019 at 09:57:14AM +0200, Christian Brauner wrote: > BugLink: https://bugs.launchpad.net/bugs/1846265 > > This commit simplifies how shiftfs open files, both regular files an > directories. > > In the first iteration, we implemented a kmem cache for struct > shiftfs_file_info which stashed away a struct path and the struct file > for the underlay. The path however was never used anywhere so the struct > shiftfs_file_info and therefore the whole kmem cache can go away. > Instead we move to the same model as overlayfs and just stash away the > struct file for the underlay in file->private_data of the shiftfs struct > file. > Addtionally, we split the .open method for files and directories. > Similar to overlayfs .open for regular files uses open_with_fake_path() > which ensures that it doesn't contribute to the open file count (since > this would mean we'd count double). The .open method for directories > however used dentry_open() which contributes to the open file count. > > The basic logic for opening files is unchanged. The main point is to > ensure that a reference to the underlay's dentry is kept through struct > path. > > Various bits and pieces of this were cooked up in discussions Seth and I > had in Paris. > > Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Looks sane, scope limited to shiftfs. Acked-by: Seth Forshee <seth.forshee@canonical.com> Applied to unstable/master, thanks!
On Tue Oct 15, 2019 at 1:25 PM Seth Forshee wrote: > On Wed, Oct 02, 2019 at 09:57:14AM +0200, Christian Brauner wrote: > > BugLink: https://bugs.launchpad.net/bugs/1846265 > > > > This commit simplifies how shiftfs open files, both regular files an > > directories. > > > > In the first iteration, we implemented a kmem cache for struct > > shiftfs_file_info which stashed away a struct path and the struct file > > for the underlay. The path however was never used anywhere so the struct > > shiftfs_file_info and therefore the whole kmem cache can go away. > > Instead we move to the same model as overlayfs and just stash away the > > struct file for the underlay in file->private_data of the shiftfs struct > > file. > > Addtionally, we split the .open method for files and directories. > > Similar to overlayfs .open for regular files uses open_with_fake_path() > > which ensures that it doesn't contribute to the open file count (since > > this would mean we'd count double). The .open method for directories > > however used dentry_open() which contributes to the open file count. > > > > The basic logic for opening files is unchanged. The main point is to > > ensure that a reference to the underlay's dentry is kept through struct > > path. > > > > Various bits and pieces of this were cooked up in discussions Seth and I > > had in Paris. > > > > Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> > > Looks sane, scope limited to shiftfs. > > Acked-by: Seth Forshee <seth.forshee@canonical.com> > > Applied to unstable/master, thanks! Thanks! Christian
On 02.10.19 09:57, Christian Brauner wrote: > BugLink: https://bugs.launchpad.net/bugs/1846265 > > This commit simplifies how shiftfs open files, both regular files an > directories. > > In the first iteration, we implemented a kmem cache for struct > shiftfs_file_info which stashed away a struct path and the struct file > for the underlay. The path however was never used anywhere so the struct > shiftfs_file_info and therefore the whole kmem cache can go away. > Instead we move to the same model as overlayfs and just stash away the > struct file for the underlay in file->private_data of the shiftfs struct > file. > Addtionally, we split the .open method for files and directories. > Similar to overlayfs .open for regular files uses open_with_fake_path() > which ensures that it doesn't contribute to the open file count (since > this would mean we'd count double). The .open method for directories > however used dentry_open() which contributes to the open file count. > > The basic logic for opening files is unchanged. The main point is to > ensure that a reference to the underlay's dentry is kept through struct > path. > > Various bits and pieces of this were cooked up in discussions Seth and I > had in Paris. > > Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> No functional change, low regression potential and good test results. Acked-by: Kleber Sacilotto de Souza <kleber.souza@canonical.com> > --- > /* v1 */ > unchanged > > /* v0 */ > Link: https://lists.ubuntu.com/archives/kernel-team/2019-October/104184.html > > Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> > --- > fs/shiftfs.c | 105 +++++++++++++++++++++++---------------------------- > 1 file changed, 47 insertions(+), 58 deletions(-) > > diff --git a/fs/shiftfs.c b/fs/shiftfs.c > index a21cb473e000..55bb32b611f2 100644 > --- a/fs/shiftfs.c > +++ b/fs/shiftfs.c > @@ -31,13 +31,6 @@ struct shiftfs_super_info { > unsigned int passthrough_mark; > }; > > -struct shiftfs_file_info { > - struct path realpath; > - struct file *realfile; > -}; > - > -struct kmem_cache *shiftfs_file_info_cache; > - > static void shiftfs_fill_inode(struct inode *inode, unsigned long ino, > umode_t mode, dev_t dev, struct dentry *dentry); > > @@ -1042,21 +1035,21 @@ static const struct inode_operations shiftfs_symlink_inode_operations = { > }; > > static struct file *shiftfs_open_realfile(const struct file *file, > - struct path *realpath) > + struct inode *realinode) > { > - struct file *lowerf; > - const struct cred *oldcred; > + struct file *realfile; > + const struct cred *old_cred; > struct inode *inode = file_inode(file); > - struct inode *loweri = realpath->dentry->d_inode; > + struct dentry *lowerd = file->f_path.dentry->d_fsdata; > struct shiftfs_super_info *info = inode->i_sb->s_fs_info; > + struct path realpath = { .mnt = info->mnt, .dentry = lowerd }; > > - oldcred = shiftfs_override_creds(inode->i_sb); > - /* XXX: open_with_fake_path() not gauranteed to stay around, if > - * removed use dentry_open() */ > - lowerf = open_with_fake_path(realpath, file->f_flags, loweri, info->creator_cred); > - revert_creds(oldcred); > + old_cred = shiftfs_override_creds(inode->i_sb); > + realfile = open_with_fake_path(&realpath, file->f_flags, realinode, > + info->creator_cred); > + revert_creds(old_cred); > > - return lowerf; > + return realfile; > } > > #define SHIFTFS_SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | O_DIRECT) > @@ -1096,8 +1089,7 @@ static int shiftfs_change_flags(struct file *file, unsigned int flags) > > static int shiftfs_real_fdget(const struct file *file, struct fd *lowerfd) > { > - struct shiftfs_file_info *file_info = file->private_data; > - struct file *realfile = file_info->realfile; > + struct file *realfile = file->private_data; > > lowerfd->flags = 0; > lowerfd->file = realfile; > @@ -1111,51 +1103,57 @@ static int shiftfs_real_fdget(const struct file *file, struct fd *lowerfd) > > static int shiftfs_open(struct inode *inode, struct file *file) > { > - struct shiftfs_super_info *ssi = inode->i_sb->s_fs_info; > - struct shiftfs_file_info *file_info; > struct file *realfile; > - struct path *realpath; > > - file_info = kmem_cache_zalloc(shiftfs_file_info_cache, GFP_KERNEL); > - if (!file_info) > - return -ENOMEM; > - > - realpath = &file_info->realpath; > - realpath->mnt = ssi->mnt; > - realpath->dentry = file->f_path.dentry->d_fsdata; > - > - realfile = shiftfs_open_realfile(file, realpath); > - if (IS_ERR(realfile)) { > - kmem_cache_free(shiftfs_file_info_cache, file_info); > + realfile = shiftfs_open_realfile(file, inode->i_private); > + if (IS_ERR(realfile)) > return PTR_ERR(realfile); > - } > > - file->private_data = file_info; > + file->private_data = realfile; > /* For O_DIRECT dentry_open() checks f_mapping->a_ops->direct_IO. */ > file->f_mapping = realfile->f_mapping; > > - file_info->realfile = realfile; > return 0; > } > > -static int shiftfs_release(struct inode *inode, struct file *file) > +static int shiftfs_dir_open(struct inode *inode, struct file *file) > { > - struct shiftfs_file_info *file_info = file->private_data; > + struct file *realfile; > + const struct cred *oldcred; > + struct dentry *lowerd = file->f_path.dentry->d_fsdata; > + struct shiftfs_super_info *info = inode->i_sb->s_fs_info; > + struct path realpath = { .mnt = info->mnt, .dentry = lowerd }; > + > + oldcred = shiftfs_override_creds(file->f_path.dentry->d_sb); > + realfile = dentry_open(&realpath, file->f_flags | O_NOATIME, > + info->creator_cred); > + revert_creds(oldcred); > + if (IS_ERR(realfile)) > + return PTR_ERR(realfile); > > - if (file_info) { > - if (file_info->realfile) > - fput(file_info->realfile); > + file->private_data = realfile; > > - kmem_cache_free(shiftfs_file_info_cache, file_info); > - } > + return 0; > +} > + > +static int shiftfs_release(struct inode *inode, struct file *file) > +{ > + struct file *realfile = file->private_data; > + > + if (realfile) > + fput(realfile); > > return 0; > } > > +static int shiftfs_dir_release(struct inode *inode, struct file *file) > +{ > + return shiftfs_release(inode, file); > +} > + > static loff_t shiftfs_dir_llseek(struct file *file, loff_t offset, int whence) > { > - struct shiftfs_file_info *file_info = file->private_data; > - struct file *realfile = file_info->realfile; > + struct file *realfile = file->private_data; > > return vfs_llseek(realfile, offset, whence); > } > @@ -1274,8 +1272,7 @@ static int shiftfs_fsync(struct file *file, loff_t start, loff_t end, > > static int shiftfs_mmap(struct file *file, struct vm_area_struct *vma) > { > - struct shiftfs_file_info *file_info = file->private_data; > - struct file *realfile = file_info->realfile; > + struct file *realfile = file->private_data; > const struct cred *oldcred; > int ret; > > @@ -1671,8 +1668,7 @@ static int shiftfs_iterate_shared(struct file *file, struct dir_context *ctx) > { > const struct cred *oldcred; > int err = -ENOTDIR; > - struct shiftfs_file_info *file_info = file->private_data; > - struct file *realfile = file_info->realfile; > + struct file *realfile = file->private_data; > > oldcred = shiftfs_override_creds(file->f_path.dentry->d_sb); > err = iterate_dir(realfile, ctx); > @@ -1698,13 +1694,13 @@ const struct file_operations shiftfs_file_operations = { > }; > > const struct file_operations shiftfs_dir_operations = { > + .open = shiftfs_dir_open, > + .release = shiftfs_dir_release, > .compat_ioctl = shiftfs_compat_ioctl, > .fsync = shiftfs_fsync, > .iterate_shared = shiftfs_iterate_shared, > .llseek = shiftfs_dir_llseek, > - .open = shiftfs_open, > .read = generic_read_dir, > - .release = shiftfs_release, > .unlocked_ioctl = shiftfs_ioctl, > }; > > @@ -2106,19 +2102,12 @@ static struct file_system_type shiftfs_type = { > > static int __init shiftfs_init(void) > { > - shiftfs_file_info_cache = kmem_cache_create( > - "shiftfs_file_info_cache", sizeof(struct shiftfs_file_info), 0, > - SLAB_RECLAIM_ACCOUNT | SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT | SLAB_MEM_SPREAD, NULL); > - if (!shiftfs_file_info_cache) > - return -ENOMEM; > - > return register_filesystem(&shiftfs_type); > } > > static void __exit shiftfs_exit(void) > { > unregister_filesystem(&shiftfs_type); > - kmem_cache_destroy(shiftfs_file_info_cache); > } > > MODULE_ALIAS_FS("shiftfs"); >
On 02.10.19 09:57, Christian Brauner wrote: > BugLink: https://bugs.launchpad.net/bugs/1846265 > > This commit simplifies how shiftfs open files, both regular files an > directories. > > In the first iteration, we implemented a kmem cache for struct > shiftfs_file_info which stashed away a struct path and the struct file > for the underlay. The path however was never used anywhere so the struct > shiftfs_file_info and therefore the whole kmem cache can go away. > Instead we move to the same model as overlayfs and just stash away the > struct file for the underlay in file->private_data of the shiftfs struct > file. > Addtionally, we split the .open method for files and directories. > Similar to overlayfs .open for regular files uses open_with_fake_path() > which ensures that it doesn't contribute to the open file count (since > this would mean we'd count double). The .open method for directories > however used dentry_open() which contributes to the open file count. > > The basic logic for opening files is unchanged. The main point is to > ensure that a reference to the underlay's dentry is kept through struct > path. > > Various bits and pieces of this were cooked up in discussions Seth and I > had in Paris. > > Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> Applied to eoan/master-next branch. Thanks, Kleber > --- > /* v1 */ > unchanged > > /* v0 */ > Link: https://lists.ubuntu.com/archives/kernel-team/2019-October/104184.html > > Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com> > --- > fs/shiftfs.c | 105 +++++++++++++++++++++++---------------------------- > 1 file changed, 47 insertions(+), 58 deletions(-) > > diff --git a/fs/shiftfs.c b/fs/shiftfs.c > index a21cb473e000..55bb32b611f2 100644 > --- a/fs/shiftfs.c > +++ b/fs/shiftfs.c > @@ -31,13 +31,6 @@ struct shiftfs_super_info { > unsigned int passthrough_mark; > }; > > -struct shiftfs_file_info { > - struct path realpath; > - struct file *realfile; > -}; > - > -struct kmem_cache *shiftfs_file_info_cache; > - > static void shiftfs_fill_inode(struct inode *inode, unsigned long ino, > umode_t mode, dev_t dev, struct dentry *dentry); > > @@ -1042,21 +1035,21 @@ static const struct inode_operations shiftfs_symlink_inode_operations = { > }; > > static struct file *shiftfs_open_realfile(const struct file *file, > - struct path *realpath) > + struct inode *realinode) > { > - struct file *lowerf; > - const struct cred *oldcred; > + struct file *realfile; > + const struct cred *old_cred; > struct inode *inode = file_inode(file); > - struct inode *loweri = realpath->dentry->d_inode; > + struct dentry *lowerd = file->f_path.dentry->d_fsdata; > struct shiftfs_super_info *info = inode->i_sb->s_fs_info; > + struct path realpath = { .mnt = info->mnt, .dentry = lowerd }; > > - oldcred = shiftfs_override_creds(inode->i_sb); > - /* XXX: open_with_fake_path() not gauranteed to stay around, if > - * removed use dentry_open() */ > - lowerf = open_with_fake_path(realpath, file->f_flags, loweri, info->creator_cred); > - revert_creds(oldcred); > + old_cred = shiftfs_override_creds(inode->i_sb); > + realfile = open_with_fake_path(&realpath, file->f_flags, realinode, > + info->creator_cred); > + revert_creds(old_cred); > > - return lowerf; > + return realfile; > } > > #define SHIFTFS_SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | O_DIRECT) > @@ -1096,8 +1089,7 @@ static int shiftfs_change_flags(struct file *file, unsigned int flags) > > static int shiftfs_real_fdget(const struct file *file, struct fd *lowerfd) > { > - struct shiftfs_file_info *file_info = file->private_data; > - struct file *realfile = file_info->realfile; > + struct file *realfile = file->private_data; > > lowerfd->flags = 0; > lowerfd->file = realfile; > @@ -1111,51 +1103,57 @@ static int shiftfs_real_fdget(const struct file *file, struct fd *lowerfd) > > static int shiftfs_open(struct inode *inode, struct file *file) > { > - struct shiftfs_super_info *ssi = inode->i_sb->s_fs_info; > - struct shiftfs_file_info *file_info; > struct file *realfile; > - struct path *realpath; > > - file_info = kmem_cache_zalloc(shiftfs_file_info_cache, GFP_KERNEL); > - if (!file_info) > - return -ENOMEM; > - > - realpath = &file_info->realpath; > - realpath->mnt = ssi->mnt; > - realpath->dentry = file->f_path.dentry->d_fsdata; > - > - realfile = shiftfs_open_realfile(file, realpath); > - if (IS_ERR(realfile)) { > - kmem_cache_free(shiftfs_file_info_cache, file_info); > + realfile = shiftfs_open_realfile(file, inode->i_private); > + if (IS_ERR(realfile)) > return PTR_ERR(realfile); > - } > > - file->private_data = file_info; > + file->private_data = realfile; > /* For O_DIRECT dentry_open() checks f_mapping->a_ops->direct_IO. */ > file->f_mapping = realfile->f_mapping; > > - file_info->realfile = realfile; > return 0; > } > > -static int shiftfs_release(struct inode *inode, struct file *file) > +static int shiftfs_dir_open(struct inode *inode, struct file *file) > { > - struct shiftfs_file_info *file_info = file->private_data; > + struct file *realfile; > + const struct cred *oldcred; > + struct dentry *lowerd = file->f_path.dentry->d_fsdata; > + struct shiftfs_super_info *info = inode->i_sb->s_fs_info; > + struct path realpath = { .mnt = info->mnt, .dentry = lowerd }; > + > + oldcred = shiftfs_override_creds(file->f_path.dentry->d_sb); > + realfile = dentry_open(&realpath, file->f_flags | O_NOATIME, > + info->creator_cred); > + revert_creds(oldcred); > + if (IS_ERR(realfile)) > + return PTR_ERR(realfile); > > - if (file_info) { > - if (file_info->realfile) > - fput(file_info->realfile); > + file->private_data = realfile; > > - kmem_cache_free(shiftfs_file_info_cache, file_info); > - } > + return 0; > +} > + > +static int shiftfs_release(struct inode *inode, struct file *file) > +{ > + struct file *realfile = file->private_data; > + > + if (realfile) > + fput(realfile); > > return 0; > } > > +static int shiftfs_dir_release(struct inode *inode, struct file *file) > +{ > + return shiftfs_release(inode, file); > +} > + > static loff_t shiftfs_dir_llseek(struct file *file, loff_t offset, int whence) > { > - struct shiftfs_file_info *file_info = file->private_data; > - struct file *realfile = file_info->realfile; > + struct file *realfile = file->private_data; > > return vfs_llseek(realfile, offset, whence); > } > @@ -1274,8 +1272,7 @@ static int shiftfs_fsync(struct file *file, loff_t start, loff_t end, > > static int shiftfs_mmap(struct file *file, struct vm_area_struct *vma) > { > - struct shiftfs_file_info *file_info = file->private_data; > - struct file *realfile = file_info->realfile; > + struct file *realfile = file->private_data; > const struct cred *oldcred; > int ret; > > @@ -1671,8 +1668,7 @@ static int shiftfs_iterate_shared(struct file *file, struct dir_context *ctx) > { > const struct cred *oldcred; > int err = -ENOTDIR; > - struct shiftfs_file_info *file_info = file->private_data; > - struct file *realfile = file_info->realfile; > + struct file *realfile = file->private_data; > > oldcred = shiftfs_override_creds(file->f_path.dentry->d_sb); > err = iterate_dir(realfile, ctx); > @@ -1698,13 +1694,13 @@ const struct file_operations shiftfs_file_operations = { > }; > > const struct file_operations shiftfs_dir_operations = { > + .open = shiftfs_dir_open, > + .release = shiftfs_dir_release, > .compat_ioctl = shiftfs_compat_ioctl, > .fsync = shiftfs_fsync, > .iterate_shared = shiftfs_iterate_shared, > .llseek = shiftfs_dir_llseek, > - .open = shiftfs_open, > .read = generic_read_dir, > - .release = shiftfs_release, > .unlocked_ioctl = shiftfs_ioctl, > }; > > @@ -2106,19 +2102,12 @@ static struct file_system_type shiftfs_type = { > > static int __init shiftfs_init(void) > { > - shiftfs_file_info_cache = kmem_cache_create( > - "shiftfs_file_info_cache", sizeof(struct shiftfs_file_info), 0, > - SLAB_RECLAIM_ACCOUNT | SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT | SLAB_MEM_SPREAD, NULL); > - if (!shiftfs_file_info_cache) > - return -ENOMEM; > - > return register_filesystem(&shiftfs_type); > } > > static void __exit shiftfs_exit(void) > { > unregister_filesystem(&shiftfs_type); > - kmem_cache_destroy(shiftfs_file_info_cache); > } > > MODULE_ALIAS_FS("shiftfs"); >
diff --git a/fs/shiftfs.c b/fs/shiftfs.c index a21cb473e000..55bb32b611f2 100644 --- a/fs/shiftfs.c +++ b/fs/shiftfs.c @@ -31,13 +31,6 @@ struct shiftfs_super_info { unsigned int passthrough_mark; }; -struct shiftfs_file_info { - struct path realpath; - struct file *realfile; -}; - -struct kmem_cache *shiftfs_file_info_cache; - static void shiftfs_fill_inode(struct inode *inode, unsigned long ino, umode_t mode, dev_t dev, struct dentry *dentry); @@ -1042,21 +1035,21 @@ static const struct inode_operations shiftfs_symlink_inode_operations = { }; static struct file *shiftfs_open_realfile(const struct file *file, - struct path *realpath) + struct inode *realinode) { - struct file *lowerf; - const struct cred *oldcred; + struct file *realfile; + const struct cred *old_cred; struct inode *inode = file_inode(file); - struct inode *loweri = realpath->dentry->d_inode; + struct dentry *lowerd = file->f_path.dentry->d_fsdata; struct shiftfs_super_info *info = inode->i_sb->s_fs_info; + struct path realpath = { .mnt = info->mnt, .dentry = lowerd }; - oldcred = shiftfs_override_creds(inode->i_sb); - /* XXX: open_with_fake_path() not gauranteed to stay around, if - * removed use dentry_open() */ - lowerf = open_with_fake_path(realpath, file->f_flags, loweri, info->creator_cred); - revert_creds(oldcred); + old_cred = shiftfs_override_creds(inode->i_sb); + realfile = open_with_fake_path(&realpath, file->f_flags, realinode, + info->creator_cred); + revert_creds(old_cred); - return lowerf; + return realfile; } #define SHIFTFS_SETFL_MASK (O_APPEND | O_NONBLOCK | O_NDELAY | O_DIRECT) @@ -1096,8 +1089,7 @@ static int shiftfs_change_flags(struct file *file, unsigned int flags) static int shiftfs_real_fdget(const struct file *file, struct fd *lowerfd) { - struct shiftfs_file_info *file_info = file->private_data; - struct file *realfile = file_info->realfile; + struct file *realfile = file->private_data; lowerfd->flags = 0; lowerfd->file = realfile; @@ -1111,51 +1103,57 @@ static int shiftfs_real_fdget(const struct file *file, struct fd *lowerfd) static int shiftfs_open(struct inode *inode, struct file *file) { - struct shiftfs_super_info *ssi = inode->i_sb->s_fs_info; - struct shiftfs_file_info *file_info; struct file *realfile; - struct path *realpath; - file_info = kmem_cache_zalloc(shiftfs_file_info_cache, GFP_KERNEL); - if (!file_info) - return -ENOMEM; - - realpath = &file_info->realpath; - realpath->mnt = ssi->mnt; - realpath->dentry = file->f_path.dentry->d_fsdata; - - realfile = shiftfs_open_realfile(file, realpath); - if (IS_ERR(realfile)) { - kmem_cache_free(shiftfs_file_info_cache, file_info); + realfile = shiftfs_open_realfile(file, inode->i_private); + if (IS_ERR(realfile)) return PTR_ERR(realfile); - } - file->private_data = file_info; + file->private_data = realfile; /* For O_DIRECT dentry_open() checks f_mapping->a_ops->direct_IO. */ file->f_mapping = realfile->f_mapping; - file_info->realfile = realfile; return 0; } -static int shiftfs_release(struct inode *inode, struct file *file) +static int shiftfs_dir_open(struct inode *inode, struct file *file) { - struct shiftfs_file_info *file_info = file->private_data; + struct file *realfile; + const struct cred *oldcred; + struct dentry *lowerd = file->f_path.dentry->d_fsdata; + struct shiftfs_super_info *info = inode->i_sb->s_fs_info; + struct path realpath = { .mnt = info->mnt, .dentry = lowerd }; + + oldcred = shiftfs_override_creds(file->f_path.dentry->d_sb); + realfile = dentry_open(&realpath, file->f_flags | O_NOATIME, + info->creator_cred); + revert_creds(oldcred); + if (IS_ERR(realfile)) + return PTR_ERR(realfile); - if (file_info) { - if (file_info->realfile) - fput(file_info->realfile); + file->private_data = realfile; - kmem_cache_free(shiftfs_file_info_cache, file_info); - } + return 0; +} + +static int shiftfs_release(struct inode *inode, struct file *file) +{ + struct file *realfile = file->private_data; + + if (realfile) + fput(realfile); return 0; } +static int shiftfs_dir_release(struct inode *inode, struct file *file) +{ + return shiftfs_release(inode, file); +} + static loff_t shiftfs_dir_llseek(struct file *file, loff_t offset, int whence) { - struct shiftfs_file_info *file_info = file->private_data; - struct file *realfile = file_info->realfile; + struct file *realfile = file->private_data; return vfs_llseek(realfile, offset, whence); } @@ -1274,8 +1272,7 @@ static int shiftfs_fsync(struct file *file, loff_t start, loff_t end, static int shiftfs_mmap(struct file *file, struct vm_area_struct *vma) { - struct shiftfs_file_info *file_info = file->private_data; - struct file *realfile = file_info->realfile; + struct file *realfile = file->private_data; const struct cred *oldcred; int ret; @@ -1671,8 +1668,7 @@ static int shiftfs_iterate_shared(struct file *file, struct dir_context *ctx) { const struct cred *oldcred; int err = -ENOTDIR; - struct shiftfs_file_info *file_info = file->private_data; - struct file *realfile = file_info->realfile; + struct file *realfile = file->private_data; oldcred = shiftfs_override_creds(file->f_path.dentry->d_sb); err = iterate_dir(realfile, ctx); @@ -1698,13 +1694,13 @@ const struct file_operations shiftfs_file_operations = { }; const struct file_operations shiftfs_dir_operations = { + .open = shiftfs_dir_open, + .release = shiftfs_dir_release, .compat_ioctl = shiftfs_compat_ioctl, .fsync = shiftfs_fsync, .iterate_shared = shiftfs_iterate_shared, .llseek = shiftfs_dir_llseek, - .open = shiftfs_open, .read = generic_read_dir, - .release = shiftfs_release, .unlocked_ioctl = shiftfs_ioctl, }; @@ -2106,19 +2102,12 @@ static struct file_system_type shiftfs_type = { static int __init shiftfs_init(void) { - shiftfs_file_info_cache = kmem_cache_create( - "shiftfs_file_info_cache", sizeof(struct shiftfs_file_info), 0, - SLAB_RECLAIM_ACCOUNT | SLAB_HWCACHE_ALIGN | SLAB_ACCOUNT | SLAB_MEM_SPREAD, NULL); - if (!shiftfs_file_info_cache) - return -ENOMEM; - return register_filesystem(&shiftfs_type); } static void __exit shiftfs_exit(void) { unregister_filesystem(&shiftfs_type); - kmem_cache_destroy(shiftfs_file_info_cache); } MODULE_ALIAS_FS("shiftfs");