From: Amir Goldstein <amir73il@gmail.com> mainline inclusion from mainline-v6.9-rc1 commit 57e1176e6086673d31bf0a0dc58e144c8e65e589 category: feature bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBHLU4 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- Use the backing file read/write helpers to implement read/write passthrough to a backing file. After read/write, we invalidate a/c/mtime/size attributes. Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Yifan Qiao <qiaoyifan4@huawei.com> --- fs/fuse/fuse_i.h | 3 ++ fs/fuse/file.c | 18 +++++++---- fs/fuse/passthrough.c | 69 +++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 84 insertions(+), 6 deletions(-) diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h index 2eb882af0696..7607085e7db0 100644 --- a/fs/fuse/fuse_i.h +++ b/fs/fuse/fuse_i.h @@ -1482,4 +1482,7 @@ static inline struct file *fuse_file_passthrough(struct fuse_file *ff) #endif } +ssize_t fuse_passthrough_read_iter(struct kiocb *iocb, struct iov_iter *iter); +ssize_t fuse_passthrough_write_iter(struct kiocb *iocb, struct iov_iter *iter); + #endif /* _FS_FUSE_I_H */ diff --git a/fs/fuse/file.c b/fs/fuse/file.c index d192c44e8a5d..daa94bc4041f 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -1716,10 +1716,13 @@ static ssize_t fuse_file_read_iter(struct kiocb *iocb, struct iov_iter *to) if (FUSE_IS_DAX(inode)) return fuse_dax_read_iter(iocb, to); - if (!(ff->open_flags & FOPEN_DIRECT_IO)) - return fuse_cache_read_iter(iocb, to); - else + /* FOPEN_DIRECT_IO overrides FOPEN_PASSTHROUGH */ + if (ff->open_flags & FOPEN_DIRECT_IO) return fuse_direct_read_iter(iocb, to); + else if (fuse_file_passthrough(ff)) + return fuse_passthrough_read_iter(iocb, to); + else + return fuse_cache_read_iter(iocb, to); } static ssize_t fuse_file_write_iter(struct kiocb *iocb, struct iov_iter *from) @@ -1734,10 +1737,13 @@ static ssize_t fuse_file_write_iter(struct kiocb *iocb, struct iov_iter *from) if (FUSE_IS_DAX(inode)) return fuse_dax_write_iter(iocb, from); - if (!(ff->open_flags & FOPEN_DIRECT_IO)) - return fuse_cache_write_iter(iocb, from); - else + /* FOPEN_DIRECT_IO overrides FOPEN_PASSTHROUGH */ + if (ff->open_flags & FOPEN_DIRECT_IO) return fuse_direct_write_iter(iocb, from); + else if (fuse_file_passthrough(ff)) + return fuse_passthrough_write_iter(iocb, from); + else + return fuse_cache_write_iter(iocb, from); } static void fuse_writepage_free(struct fuse_writepage_args *wpa) diff --git a/fs/fuse/passthrough.c b/fs/fuse/passthrough.c index dc054d2ab13e..0e5d316bdad3 100644 --- a/fs/fuse/passthrough.c +++ b/fs/fuse/passthrough.c @@ -10,6 +10,75 @@ #include <linux/file.h> #include <linux/backing-file.h> +static void fuse_file_accessed(struct file *file) +{ + struct inode *inode = file_inode(file); + + fuse_invalidate_atime(inode); +} + +static void fuse_file_modified(struct file *file) +{ + struct inode *inode = file_inode(file); + + fuse_invalidate_attr_mask(inode, FUSE_STATX_MODSIZE); +} + +ssize_t fuse_passthrough_read_iter(struct kiocb *iocb, struct iov_iter *iter) +{ + struct file *file = iocb->ki_filp; + struct fuse_file *ff = file->private_data; + struct file *backing_file = fuse_file_passthrough(ff); + size_t count = iov_iter_count(iter); + ssize_t ret; + struct backing_file_ctx ctx = { + .cred = ff->cred, + .user_file = file, + .accessed = fuse_file_accessed, + }; + + + pr_debug("%s: backing_file=0x%p, pos=%lld, len=%zu\n", __func__, + backing_file, iocb->ki_pos, count); + + if (!count) + return 0; + + ret = backing_file_read_iter(backing_file, iter, iocb, iocb->ki_flags, + &ctx); + + return ret; +} + +ssize_t fuse_passthrough_write_iter(struct kiocb *iocb, + struct iov_iter *iter) +{ + struct file *file = iocb->ki_filp; + struct inode *inode = file_inode(file); + struct fuse_file *ff = file->private_data; + struct file *backing_file = fuse_file_passthrough(ff); + size_t count = iov_iter_count(iter); + ssize_t ret; + struct backing_file_ctx ctx = { + .cred = ff->cred, + .user_file = file, + .end_write = fuse_file_modified, + }; + + pr_debug("%s: backing_file=0x%p, pos=%lld, len=%zu\n", __func__, + backing_file, iocb->ki_pos, count); + + if (!count) + return 0; + + inode_lock(inode); + ret = backing_file_write_iter(backing_file, iter, iocb, iocb->ki_flags, + &ctx); + inode_unlock(inode); + + return ret; +} + struct fuse_backing *fuse_backing_get(struct fuse_backing *fb) { if (fb && refcount_inc_not_zero(&fb->count)) -- 2.39.2