Commit 793b80ef authored by Christoph Hellwig's avatar Christoph Hellwig Committed by Al Viro
Browse files

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: default avatarMilosz Tanski <milosz@adfin.com>
[hch: rebased on top of my kiocb changes]
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
Reviewed-by: default avatarStephen Bates <stephen.bates@pmcs.com>
Tested-by: default avatarStephen Bates <stephen.bates@pmcs.com>
Acked-by: default avatarJeff Moyer <jmoyer@redhat.com>
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 92e963f5

fs/nfsd/vfs.c

+2 −2
Original line number Diff line number Diff line
@@ -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;

fs/read_write.c

+26 −18
Original line number Diff line number Diff line
@@ -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)

fs/splice.c

+1 −1
Original line number Diff line number Diff line
@@ -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;

include/linux/fs.h

+2 −2
Original line number Diff line number Diff line
@@ -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,

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