From 793b80ef14af56d20c998265287648ad34239b6f Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Thu, 3 Mar 2016 16:03:58 +0100 Subject: [PATCH] vfs: pass a flags argument to vfs_readv/vfs_writev This way we can set kiocb flags also from the sync read/write path for the read_iter/write_iter operations. For now there is no way to pass flags to plain read/write operations as there is no real need for that, and all flags passed are explicitly rejected for these files. Signed-off-by: Milosz Tanski [hch: rebased on top of my kiocb changes] Signed-off-by: Christoph Hellwig Reviewed-by: Stephen Bates Tested-by: Stephen Bates Acked-by: Jeff Moyer Signed-off-by: Al Viro --- fs/nfsd/vfs.c | 4 ++-- fs/read_write.c | 44 ++++++++++++++++++++++++++------------------ fs/splice.c | 2 +- include/linux/fs.h | 4 ++-- 4 files changed, 31 insertions(+), 23 deletions(-) diff --git a/fs/nfsd/vfs.c b/fs/nfsd/vfs.c index 5d2a57e4c03a..d40010e4f1a9 100644 --- a/fs/nfsd/vfs.c +++ b/fs/nfsd/vfs.c @@ -870,7 +870,7 @@ __be32 nfsd_readv(struct file *file, loff_t offset, struct kvec *vec, int vlen, oldfs = get_fs(); set_fs(KERNEL_DS); - host_err = vfs_readv(file, (struct iovec __user *)vec, vlen, &offset); + host_err = vfs_readv(file, (struct iovec __user *)vec, vlen, &offset, 0); set_fs(oldfs); return nfsd_finish_read(file, count, host_err); } @@ -957,7 +957,7 @@ nfsd_vfs_write(struct svc_rqst *rqstp, struct svc_fh *fhp, struct file *file, /* Write the data. */ oldfs = get_fs(); set_fs(KERNEL_DS); - host_err = vfs_writev(file, (struct iovec __user *)vec, vlen, &pos); + host_err = vfs_writev(file, (struct iovec __user *)vec, vlen, &pos, 0); set_fs(oldfs); if (host_err < 0) goto out_nfserr; diff --git a/fs/read_write.c b/fs/read_write.c index 324ec271cc4e..7d453c3e1cb6 100644 --- a/fs/read_write.c +++ b/fs/read_write.c @@ -692,11 +692,14 @@ unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to) EXPORT_SYMBOL(iov_shorten); static ssize_t do_iter_readv_writev(struct file *filp, struct iov_iter *iter, - loff_t *ppos, iter_fn_t fn) + loff_t *ppos, iter_fn_t fn, int flags) { struct kiocb kiocb; ssize_t ret; + if (flags) + return -EOPNOTSUPP; + init_sync_kiocb(&kiocb, filp); kiocb.ki_pos = *ppos; @@ -708,10 +711,13 @@ static ssize_t do_iter_readv_writev(struct file *filp, struct iov_iter *iter, /* Do it by hand, with file-ops */ static ssize_t do_loop_readv_writev(struct file *filp, struct iov_iter *iter, - loff_t *ppos, io_fn_t fn) + loff_t *ppos, io_fn_t fn, int flags) { ssize_t ret = 0; + if (flags) + return -EOPNOTSUPP; + while (iov_iter_count(iter)) { struct iovec iovec = iov_iter_iovec(iter); ssize_t nr; @@ -812,7 +818,8 @@ out: static ssize_t do_readv_writev(int type, struct file *file, const struct iovec __user * uvector, - unsigned long nr_segs, loff_t *pos) + unsigned long nr_segs, loff_t *pos, + int flags) { size_t tot_len; struct iovec iovstack[UIO_FASTIOV]; @@ -844,9 +851,9 @@ static ssize_t do_readv_writev(int type, struct file *file, } if (iter_fn) - ret = do_iter_readv_writev(file, &iter, pos, iter_fn); + ret = do_iter_readv_writev(file, &iter, pos, iter_fn, flags); else - ret = do_loop_readv_writev(file, &iter, pos, fn); + ret = do_loop_readv_writev(file, &iter, pos, fn, flags); if (type != READ) file_end_write(file); @@ -863,27 +870,27 @@ out: } ssize_t vfs_readv(struct file *file, const struct iovec __user *vec, - unsigned long vlen, loff_t *pos) + unsigned long vlen, loff_t *pos, int flags) { if (!(file->f_mode & FMODE_READ)) return -EBADF; if (!(file->f_mode & FMODE_CAN_READ)) return -EINVAL; - return do_readv_writev(READ, file, vec, vlen, pos); + return do_readv_writev(READ, file, vec, vlen, pos, flags); } EXPORT_SYMBOL(vfs_readv); ssize_t vfs_writev(struct file *file, const struct iovec __user *vec, - unsigned long vlen, loff_t *pos) + unsigned long vlen, loff_t *pos, int flags) { if (!(file->f_mode & FMODE_WRITE)) return -EBADF; if (!(file->f_mode & FMODE_CAN_WRITE)) return -EINVAL; - return do_readv_writev(WRITE, file, vec, vlen, pos); + return do_readv_writev(WRITE, file, vec, vlen, pos, flags); } EXPORT_SYMBOL(vfs_writev); @@ -896,7 +903,7 @@ SYSCALL_DEFINE3(readv, unsigned long, fd, const struct iovec __user *, vec, if (f.file) { loff_t pos = file_pos_read(f.file); - ret = vfs_readv(f.file, vec, vlen, &pos); + ret = vfs_readv(f.file, vec, vlen, &pos, 0); if (ret >= 0) file_pos_write(f.file, pos); fdput_pos(f); @@ -916,7 +923,7 @@ SYSCALL_DEFINE3(writev, unsigned long, fd, const struct iovec __user *, vec, if (f.file) { loff_t pos = file_pos_read(f.file); - ret = vfs_writev(f.file, vec, vlen, &pos); + ret = vfs_writev(f.file, vec, vlen, &pos, 0); if (ret >= 0) file_pos_write(f.file, pos); fdput_pos(f); @@ -948,7 +955,7 @@ SYSCALL_DEFINE5(preadv, unsigned long, fd, const struct iovec __user *, vec, if (f.file) { ret = -ESPIPE; if (f.file->f_mode & FMODE_PREAD) - ret = vfs_readv(f.file, vec, vlen, &pos); + ret = vfs_readv(f.file, vec, vlen, &pos, 0); fdput(f); } @@ -972,7 +979,7 @@ SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec, if (f.file) { ret = -ESPIPE; if (f.file->f_mode & FMODE_PWRITE) - ret = vfs_writev(f.file, vec, vlen, &pos); + ret = vfs_writev(f.file, vec, vlen, &pos, 0); fdput(f); } @@ -986,7 +993,8 @@ SYSCALL_DEFINE5(pwritev, unsigned long, fd, const struct iovec __user *, vec, static ssize_t compat_do_readv_writev(int type, struct file *file, const struct compat_iovec __user *uvector, - unsigned long nr_segs, loff_t *pos) + unsigned long nr_segs, loff_t *pos, + int flags) { compat_ssize_t tot_len; struct iovec iovstack[UIO_FASTIOV]; @@ -1018,9 +1026,9 @@ static ssize_t compat_do_readv_writev(int type, struct file *file, } if (iter_fn) - ret = do_iter_readv_writev(file, &iter, pos, iter_fn); + ret = do_iter_readv_writev(file, &iter, pos, iter_fn, flags); else - ret = do_loop_readv_writev(file, &iter, pos, fn); + ret = do_loop_readv_writev(file, &iter, pos, fn, flags); if (type != READ) file_end_write(file); @@ -1049,7 +1057,7 @@ static size_t compat_readv(struct file *file, if (!(file->f_mode & FMODE_CAN_READ)) goto out; - ret = compat_do_readv_writev(READ, file, vec, vlen, pos); + ret = compat_do_readv_writev(READ, file, vec, vlen, pos, 0); out: if (ret > 0) @@ -1126,7 +1134,7 @@ static size_t compat_writev(struct file *file, if (!(file->f_mode & FMODE_CAN_WRITE)) goto out; - ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos); + ret = compat_do_readv_writev(WRITE, file, vec, vlen, pos, 0); out: if (ret > 0) diff --git a/fs/splice.c b/fs/splice.c index 82bc0d64fc38..3dc142637ab5 100644 --- a/fs/splice.c +++ b/fs/splice.c @@ -577,7 +577,7 @@ static ssize_t kernel_readv(struct file *file, const struct iovec *vec, old_fs = get_fs(); set_fs(get_ds()); /* The cast to a user pointer is valid due to the set_fs() */ - res = vfs_readv(file, (const struct iovec __user *)vec, vlen, &pos); + res = vfs_readv(file, (const struct iovec __user *)vec, vlen, &pos, 0); set_fs(old_fs); return res; diff --git a/include/linux/fs.h b/include/linux/fs.h index 1a2046275cdf..6ec87964644f 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -1712,9 +1712,9 @@ extern ssize_t __vfs_write(struct file *, const char __user *, size_t, loff_t *) extern ssize_t vfs_read(struct file *, char __user *, size_t, loff_t *); extern ssize_t vfs_write(struct file *, const char __user *, size_t, loff_t *); extern ssize_t vfs_readv(struct file *, const struct iovec __user *, - unsigned long, loff_t *); + unsigned long, loff_t *, int); extern ssize_t vfs_writev(struct file *, const struct iovec __user *, - unsigned long, loff_t *); + unsigned long, loff_t *, int); extern ssize_t vfs_copy_file_range(struct file *, loff_t , struct file *, loff_t, size_t, unsigned int); extern int vfs_clone_file_range(struct file *file_in, loff_t pos_in, -- 2.11.0