Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull more set_fs removal from Al Viro:
 "Christoph's 'use kernel_read and friends rather than open-coding
  set_fs()' series"

* 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: unexport vfs_readv and vfs_writev
  fs: unexport vfs_read and vfs_write
  fs: unexport __vfs_read/__vfs_write
  lustre: switch to kernel_write
  gadget/f_mass_storage: stop messing with the address limit
  mconsole: switch to kernel_read
  btrfs: switch write_buf to kernel_write
  net/9p: switch p9_fd_read to kernel_write
  mm/nommu: switch do_mmap_private to kernel_read
  serial2002: switch serial2002_tty_write to kernel_{read/write}
  fs: make the buf argument to __kernel_write a void pointer
  fs: fix kernel_write prototype
  fs: fix kernel_read prototype
  fs: move kernel_read to fs/read_write.c
  fs: move kernel_write to fs/read_write.c
  autofs4: switch autofs4_write to __kernel_write
  ashmem: switch to ->read_iter

4 files changed, 16 insertions, 54 deletions

diff --git a/drivers/staging/android/ashmem.c b/drivers/staging/android/ashmem.c
index 6ba270e0494d..0f695df14c9d 100644
--- a/drivers/staging/android/ashmem.c
+++ b/drivers/staging/android/ashmem.c
@@ -294,19 +294,9 @@ static int ashmem_release(struct inode *ignored, struct file *file)
 	return 0;
 }
 
-/**
- * ashmem_read() - Reads a set of bytes from an Ashmem-enabled file
- * @file:	   The associated backing file.
- * @buf:	   The buffer of data being written to
- * @len:	   The number of bytes being read
- * @pos:	   The position of the first byte to read.
- *
- * Return: 0 if successful, or another return code if not.
- */
-static ssize_t ashmem_read(struct file *file, char __user *buf,
-			   size_t len, loff_t *pos)
+static ssize_t ashmem_read_iter(struct kiocb *iocb, struct iov_iter *iter)
 {
-	struct ashmem_area *asma = file->private_data;
+	struct ashmem_area *asma = iocb->ki_filp->private_data;
 	int ret = 0;
 
 	mutex_lock(&ashmem_mutex);
@@ -320,20 +310,17 @@ static ssize_t ashmem_read(struct file *file, char __user *buf,
 		goto out_unlock;
 	}
 
-	mutex_unlock(&ashmem_mutex);
-
 	/*
 	 * asma and asma->file are used outside the lock here.  We assume
 	 * once asma->file is set it will never be changed, and will not
 	 * be destroyed until all references to the file are dropped and
 	 * ashmem_release is called.
 	 */
-	ret = __vfs_read(asma->file, buf, len, pos);
-	if (ret >= 0)
-		/** Update backing file pos, since f_ops->read() doesn't */
-		asma->file->f_pos = *pos;
-	return ret;
-
+	mutex_unlock(&ashmem_mutex);
+	ret = vfs_iter_read(asma->file, iter, &iocb->ki_pos, 0);
+	mutex_lock(&ashmem_mutex);
+	if (ret > 0)
+		asma->file->f_pos = iocb->ki_pos;
 out_unlock:
 	mutex_unlock(&ashmem_mutex);
 	return ret;
@@ -834,7 +821,7 @@ static const struct file_operations ashmem_fops = {
 	.owner = THIS_MODULE,
 	.open = ashmem_open,
 	.release = ashmem_release,
-	.read = ashmem_read,
+	.read_iter = ashmem_read_iter,
 	.llseek = ashmem_llseek,
 	.mmap = ashmem_mmap,
 	.unlocked_ioctl = ashmem_ioctl,
diff --git a/drivers/staging/comedi/drivers/serial2002.c b/drivers/staging/comedi/drivers/serial2002.c
index 0d33e520f635..cc18e25103ca 100644
--- a/drivers/staging/comedi/drivers/serial2002.c
+++ b/drivers/staging/comedi/drivers/serial2002.c
@@ -106,16 +106,8 @@ static long serial2002_tty_ioctl(struct file *f, unsigned int op,
 
 static int serial2002_tty_write(struct file *f, unsigned char *buf, int count)
 {
-	const char __user *p = (__force const char __user *)buf;
-	int result;
-	loff_t offset = 0;
-	mm_segment_t oldfs;
-
-	oldfs = get_fs();
-	set_fs(KERNEL_DS);
-	result = __vfs_write(f, p, count, &offset);
-	set_fs(oldfs);
-	return result;
+	loff_t pos = 0;
+	return kernel_write(f, buf, count, &pos);
 }
 
 static void serial2002_tty_read_poll_wait(struct file *f, int timeout)
@@ -148,19 +140,14 @@ static int serial2002_tty_read(struct file *f, int timeout)
 {
 	unsigned char ch;
 	int result;
+	loff_t pos = 0;
 
 	result = -1;
 	if (!IS_ERR(f)) {
-		mm_segment_t oldfs;
-		char __user *p = (__force char __user *)&ch;
-		loff_t offset = 0;
-
-		oldfs = get_fs();
-		set_fs(KERNEL_DS);
 		if (f->f_op->poll) {
 			serial2002_tty_read_poll_wait(f, timeout);
 
-			if (__vfs_read(f, p, 1, &offset) == 1)
+			if (kernel_read(f, &ch, 1, &pos) == 1)
 				result = ch;
 		} else {
 			/* Device does not support poll, busy wait */
@@ -171,14 +158,13 @@ static int serial2002_tty_read(struct file *f, int timeout)
 				if (retries >= timeout)
 					break;
 
-				if (__vfs_read(f, p, 1, &offset) == 1) {
+				if (kernel_read(f, &ch, 1, &pos) == 1) {
 					result = ch;
 					break;
 				}
 				usleep_range(100, 1000);
 			}
 		}
-		set_fs(oldfs);
 	}
 	return result;
 }
diff --git a/drivers/staging/lustre/lnet/libcfs/tracefile.c b/drivers/staging/lustre/lnet/libcfs/tracefile.c
index 68f283a2744c..f916b475e767 100644
--- a/drivers/staging/lustre/lnet/libcfs/tracefile.c
+++ b/drivers/staging/lustre/lnet/libcfs/tracefile.c
@@ -731,8 +731,7 @@ int cfs_tracefile_dump_all_pages(char *filename)
 		__LASSERT_TAGE_INVARIANT(tage);
 
 		buf = kmap(tage->page);
-		rc = vfs_write(filp, (__force const char __user *)buf,
-			       tage->used, &filp->f_pos);
+		rc = kernel_write(filp, buf, tage->used, &filp->f_pos);
 		kunmap(tage->page);
 
 		if (rc != (int)tage->used) {
@@ -976,7 +975,6 @@ static int tracefiled(void *arg)
 	struct tracefiled_ctl *tctl = arg;
 	struct cfs_trace_page *tage;
 	struct cfs_trace_page *tmp;
-	mm_segment_t __oldfs;
 	struct file *filp;
 	char *buf;
 	int last_loop = 0;
@@ -1014,8 +1012,6 @@ static int tracefiled(void *arg)
 			__LASSERT(list_empty(&pc.pc_pages));
 			goto end_loop;
 		}
-		__oldfs = get_fs();
-		set_fs(get_ds());
 
 		list_for_each_entry_safe(tage, tmp, &pc.pc_pages, linkage) {
 			static loff_t f_pos;
@@ -1028,8 +1024,7 @@ static int tracefiled(void *arg)
 				f_pos = i_size_read(file_inode(filp));
 
 			buf = kmap(tage->page);
-			rc = vfs_write(filp, (__force const char __user *)buf,
-				       tage->used, &f_pos);
+			rc = kernel_write(filp, buf, tage->used, &f_pos);
 			kunmap(tage->page);
 
 			if (rc != (int)tage->used) {
@@ -1040,7 +1035,6 @@ static int tracefiled(void *arg)
 				break;
 			}
 		}
-		set_fs(__oldfs);
 
 		filp_close(filp, NULL);
 		put_pages_on_daemon_list(&pc);
diff --git a/drivers/staging/lustre/lustre/obdclass/kernelcomm.c b/drivers/staging/lustre/lustre/obdclass/kernelcomm.c
index 8f0707a27a83..4f0a42633d5a 100644
--- a/drivers/staging/lustre/lustre/obdclass/kernelcomm.c
+++ b/drivers/staging/lustre/lustre/obdclass/kernelcomm.c
@@ -52,7 +52,6 @@ int libcfs_kkuc_msg_put(struct file *filp, void *payload)
 	struct kuc_hdr *kuch = (struct kuc_hdr *)payload;
 	ssize_t count = kuch->kuc_msglen;
 	loff_t offset = 0;
-	mm_segment_t fs;
 	int rc = -ENXIO;
 
 	if (IS_ERR_OR_NULL(filp))
@@ -63,18 +62,14 @@ int libcfs_kkuc_msg_put(struct file *filp, void *payload)
 		return rc;
 	}
 
-	fs = get_fs();
-	set_fs(KERNEL_DS);
 	while (count > 0) {
-		rc = vfs_write(filp, (void __force __user *)payload,
-			       count, &offset);
+		rc = kernel_write(filp, payload, count, &offset);
 		if (rc < 0)
 			break;
 		count -= rc;
 		payload += rc;
 		rc = 0;
 	}
-	set_fs(fs);
 
 	if (rc < 0)
 		CWARN("message send failed (%d)\n", rc);