From 61536bed2149b082748f8a38c593d915ff3e5957 Mon Sep 17 00:00:00 2001 From: Amir Goldstein Date: Tue, 29 Sep 2020 15:28:47 +0800 Subject: [PATCH] ovl: support [S|G]ETFLAGS and FS[S|G]ETXATTR ioctls for directories [S|G]ETFLAGS and FS[S|G]ETXATTR ioctls are applicable to both files and directories, so add ioctl operations to dir as well. We teach ovl_real_fdget() to get the realfile of directories which use a different type of file->private_data. Ifdef away compat ioctl implementation to conform to standard practice. With this change, xfstest generic/079 which tests these ioctls on files and directories passes. Signed-off-by: Amir Goldstein Signed-off-by: Xiao Yang Signed-off-by: Miklos Szeredi --- fs/overlayfs/file.c | 16 ++++++++++++--- fs/overlayfs/overlayfs.h | 3 +++ fs/overlayfs/readdir.c | 44 ++++++++++++++++++++++++++++++++-------- 3 files changed, 51 insertions(+), 12 deletions(-) diff --git a/fs/overlayfs/file.c b/fs/overlayfs/file.c index 3582c3ae819c..443986ca564b 100644 --- a/fs/overlayfs/file.c +++ b/fs/overlayfs/file.c @@ -136,6 +136,13 @@ static int ovl_real_fdget_meta(const struct file *file, struct fd *real, static int ovl_real_fdget(const struct file *file, struct fd *real) { + if (d_is_dir(file_dentry(file))) { + real->flags = 0; + real->file = ovl_dir_real_file(file, false); + + return PTR_ERR_OR_ZERO(real->file); + } + return ovl_real_fdget_meta(file, real, false); } @@ -648,7 +655,7 @@ static long ovl_ioctl_set_fsxflags(struct file *file, unsigned int cmd, ovl_fsxflags_to_iflags(fa.fsx_xflags)); } -static long ovl_ioctl(struct file *file, unsigned int cmd, unsigned long arg) +long ovl_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { long ret; @@ -673,8 +680,8 @@ static long ovl_ioctl(struct file *file, unsigned int cmd, unsigned long arg) return ret; } -static long ovl_compat_ioctl(struct file *file, unsigned int cmd, - unsigned long arg) +#ifdef CONFIG_COMPAT +long ovl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { switch (cmd) { case FS_IOC32_GETFLAGS: @@ -691,6 +698,7 @@ static long ovl_compat_ioctl(struct file *file, unsigned int cmd, return ovl_ioctl(file, cmd, arg); } +#endif enum ovl_copyop { OVL_COPY, @@ -792,7 +800,9 @@ const struct file_operations ovl_file_operations = { .fallocate = ovl_fallocate, .fadvise = ovl_fadvise, .unlocked_ioctl = ovl_ioctl, +#ifdef CONFIG_COMPAT .compat_ioctl = ovl_compat_ioctl, +#endif .splice_read = ovl_splice_read, .splice_write = ovl_splice_write, diff --git a/fs/overlayfs/overlayfs.h b/fs/overlayfs/overlayfs.h index 7bce2469fe55..f8880aa2ba0e 100644 --- a/fs/overlayfs/overlayfs.h +++ b/fs/overlayfs/overlayfs.h @@ -416,6 +416,7 @@ static inline int ovl_verify_upper(struct ovl_fs *ofs, struct dentry *index, /* readdir.c */ extern const struct file_operations ovl_dir_operations; +struct file *ovl_dir_real_file(const struct file *file, bool want_upper); int ovl_check_empty_dir(struct dentry *dentry, struct list_head *list); void ovl_cleanup_whiteouts(struct dentry *upper, struct list_head *list); void ovl_cache_free(struct list_head *list); @@ -503,6 +504,8 @@ struct dentry *ovl_create_temp(struct dentry *workdir, struct ovl_cattr *attr); extern const struct file_operations ovl_file_operations; int __init ovl_aio_request_cache_init(void); void ovl_aio_request_cache_destroy(void); +long ovl_ioctl(struct file *file, unsigned int cmd, unsigned long arg); +long ovl_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg); /* copy_up.c */ int ovl_copy_up(struct dentry *dentry); diff --git a/fs/overlayfs/readdir.c b/fs/overlayfs/readdir.c index 596002054ac6..01620ebae1bd 100644 --- a/fs/overlayfs/readdir.c +++ b/fs/overlayfs/readdir.c @@ -840,7 +840,7 @@ out_unlock: return res; } -static struct file *ovl_dir_open_realfile(struct file *file, +static struct file *ovl_dir_open_realfile(const struct file *file, struct path *realpath) { struct file *res; @@ -853,19 +853,22 @@ static struct file *ovl_dir_open_realfile(struct file *file, return res; } -static int ovl_dir_fsync(struct file *file, loff_t start, loff_t end, - int datasync) +/* + * Like ovl_real_fdget(), returns upperfile if dir was copied up since open. + * Unlike ovl_real_fdget(), this caches upperfile in file->private_data. + * + * TODO: use same abstract type for file->private_data of dir and file so + * upperfile could also be cached for files as well. + */ +struct file *ovl_dir_real_file(const struct file *file, bool want_upper) { + struct ovl_dir_file *od = file->private_data; struct dentry *dentry = file->f_path.dentry; struct file *realfile = od->realfile; - /* Nothing to sync for lower */ if (!OVL_TYPE_UPPER(ovl_path_type(dentry))) - return 0; - - if (!ovl_should_sync(OVL_FS(dentry->d_sb))) - return 0; + return want_upper ? NULL : realfile; /* * Need to check if we started out being a lower dir, but got copied up @@ -884,7 +887,7 @@ static int ovl_dir_fsync(struct file *file, loff_t start, loff_t end, if (!od->upperfile) { if (IS_ERR(realfile)) { inode_unlock(inode); - return PTR_ERR(realfile); + return realfile; } smp_store_release(&od->upperfile, realfile); } else { @@ -897,6 +900,25 @@ static int ovl_dir_fsync(struct file *file, loff_t start, loff_t end, } } + return realfile; +} + +static int ovl_dir_fsync(struct file *file, loff_t start, loff_t end, + int datasync) +{ + struct file *realfile; + int err; + + if (!ovl_should_sync(OVL_FS(file->f_path.dentry->d_sb))) + return 0; + + realfile = ovl_dir_real_file(file, true); + err = PTR_ERR_OR_ZERO(realfile); + + /* Nothing to sync for lower */ + if (!realfile || err) + return err; + return vfs_fsync_range(realfile, start, end, datasync); } @@ -949,6 +971,10 @@ const struct file_operations ovl_dir_operations = { .llseek = ovl_dir_llseek, .fsync = ovl_dir_fsync, .release = ovl_dir_release, + .unlocked_ioctl = ovl_ioctl, +#ifdef CONFIG_COMPAT + .compat_ioctl = ovl_compat_ioctl, +#endif }; int ovl_check_empty_dir(struct dentry *dentry, struct list_head *list)