From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Jiufei Xue Subject: [PATCH 1/2] vfs: add vfs_iocb_iter_[read|write] helper functions Date: Wed, 20 Nov 2019 17:45:25 +0800 Message-Id: <1574243126-59283-2-git-send-email-jiufei.xue@linux.alibaba.com> In-Reply-To: <1574243126-59283-1-git-send-email-jiufei.xue@linux.alibaba.com> References: <1574243126-59283-1-git-send-email-jiufei.xue@linux.alibaba.com> To: miklos@szeredi.hu, amir73il@gmail.com Cc: linux-unionfs@vger.kernel.org, linux-fsdevel@vger.kernel.org List-ID: This isn't cause any behavior changes and will be used by overlay async IO implementation. Signed-off-by: Jiufei Xue --- fs/read_write.c | 58 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/fs.h | 16 +++++++++++++++ 2 files changed, 74 insertions(+) diff --git a/fs/read_write.c b/fs/read_write.c index 5bbf587..3dfbcec 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -984,6 +984,64 @@ ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos, } EXPORT_SYMBOL(vfs_iter_write); +ssize_t vfs_iocb_iter_read(struct file *file, struct kiocb *iocb, + struct iov_iter *iter) +{ + ssize_t ret = 0; + ssize_t tot_len; + + if (!file->f_op->read_iter) + return -EINVAL; + if (!(file->f_mode & FMODE_READ)) + return -EBADF; + if (!(file->f_mode & FMODE_CAN_READ)) + return -EINVAL; + + tot_len = iov_iter_count(iter); + if (!tot_len) + return 0; + + ret = rw_verify_area(READ, file, &iocb->ki_pos, tot_len); + if (ret < 0) + return ret; + + ret = call_read_iter(file, iocb, iter); + if (ret >= 0) + fsnotify_access(file); + + return ret; +} +EXPORT_SYMBOL(vfs_iocb_iter_read); + +ssize_t vfs_iocb_iter_write(struct file *file, struct kiocb *iocb, + struct iov_iter *iter) +{ + ssize_t ret = 0; + ssize_t tot_len; + + if (!file->f_op->write_iter) + return -EINVAL; + if (!(file->f_mode & FMODE_WRITE)) + return -EBADF; + if (!(file->f_mode & FMODE_CAN_WRITE)) + return -EINVAL; + + tot_len = iov_iter_count(iter); + if (!tot_len) + return 0; + + ret = rw_verify_area(WRITE, file, &iocb->ki_pos, tot_len); + if (ret < 0) + return ret; + + ret = call_write_iter(file, iocb, iter); + if (ret >= 0) + fsnotify_modify(file); + + return ret; +} +EXPORT_SYMBOL(vfs_iocb_iter_write); + ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, unsigned long vlen, loff_t *pos, rwf_t flags) { diff --git a/include/linux/fs.h b/include/linux/fs.h index e0d909d..c885279 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -2071,6 +2071,18 @@ static inline void init_sync_kiocb(struct kiocb *kiocb, struct file *filp) }; } +static inline void kiocb_clone(struct kiocb *kiocb, struct kiocb *kiocb_src, + struct file *filp) +{ + *kiocb = (struct kiocb) { + .ki_filp = filp, + .ki_flags = kiocb_src->ki_flags, + .ki_hint = ki_hint_validate(file_write_hint(filp)), + .ki_ioprio = kiocb_src->ki_ioprio, + .ki_pos = kiocb_src->ki_pos, + }; +} + /* * Inode state bits. Protected by inode->i_lock * @@ -3105,6 +3117,10 @@ ssize_t vfs_iter_read(struct file *file, struct iov_iter *iter, loff_t *ppos, rwf_t flags); ssize_t vfs_iter_write(struct file *file, struct iov_iter *iter, loff_t *ppos, rwf_t flags); +ssize_t vfs_iocb_iter_read(struct file *file, struct kiocb *iocb, + struct iov_iter *iter); +ssize_t vfs_iocb_iter_write(struct file *file, struct kiocb *iocb, + struct iov_iter *iter); /* fs/block_dev.c */ extern ssize_t blkdev_read_iter(struct kiocb *iocb, struct iov_iter *to); -- 1.8.3.1