[PATCH 102/437] lib: convert to read/write iterators

[Jens Axboe]

Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
 lib/dynamic_debug.c  |  5 +++--
 lib/kunit/debugfs.c  | 13 ++++++-------
 lib/test_firmware.c  | 10 ++++------
 lib/xz/xz_dec_test.c |  9 ++++-----
 4 files changed, 17 insertions(+), 20 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index c78f335fa981..534ad9218557 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -1022,6 +1022,7 @@ static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf,
 	*offp += len;
 	return len;
 }
+FOPS_WRITE_ITER_HELPER(ddebug_proc_write);
 
 /*
  * Set the iterator to point to the first _ddebug object
@@ -1182,10 +1183,10 @@ static int ddebug_proc_open(struct inode *inode, struct file *file)
 static const struct file_operations ddebug_proc_fops = {
 	.owner = THIS_MODULE,
 	.open = ddebug_proc_open,
-	.read = seq_read,
+	.read_iter = seq_read_iter,
 	.llseek = seq_lseek,
 	.release = seq_release_private,
-	.write = ddebug_proc_write
+	.write_iter = ddebug_proc_write_iter
 };
 
 static const struct proc_ops proc_fops = {
diff --git a/lib/kunit/debugfs.c b/lib/kunit/debugfs.c
index d548750a325a..ea7be601cf9e 100644
--- a/lib/kunit/debugfs.c
+++ b/lib/kunit/debugfs.c
@@ -139,28 +139,27 @@ static int debugfs_run_open(struct inode *inode, struct file *file)
  *
  * Note: what is written to this file will not be saved.
  */
-static ssize_t debugfs_run(struct file *file,
-		const char __user *buf, size_t count, loff_t *ppos)
+static ssize_t debugfs_run(struct kiocb *iocb, struct iov_iter *from)
 {
-	struct inode *f_inode = file->f_inode;
+	struct inode *f_inode = iocb->ki_filp->f_inode;
 	struct kunit_suite *suite = (struct kunit_suite *) f_inode->i_private;
 
 	__kunit_test_suites_init(&suite, 1);
 
-	return count;
+	return iov_iter_count(from);
 }
 
 static const struct file_operations debugfs_results_fops = {
 	.open = debugfs_results_open,
-	.read = seq_read,
+	.read_iter = seq_read_iter,
 	.llseek = seq_lseek,
 	.release = debugfs_release,
 };
 
 static const struct file_operations debugfs_run_fops = {
 	.open = debugfs_run_open,
-	.read = seq_read,
-	.write = debugfs_run,
+	.read_iter = seq_read_iter,
+	.write_iter = debugfs_run,
 	.llseek = seq_lseek,
 	.release = debugfs_release,
 };
diff --git a/lib/test_firmware.c b/lib/test_firmware.c
index 9cfdcd6d21db..face875a52e2 100644
--- a/lib/test_firmware.c
+++ b/lib/test_firmware.c
@@ -147,23 +147,21 @@ static struct test_firmware_upload *upload_lookup_name(const char *name)
 	return NULL;
 }
 
-static ssize_t test_fw_misc_read(struct file *f, char __user *buf,
-				 size_t size, loff_t *offset)
+static ssize_t test_fw_misc_read(struct kiocb *iocb, struct iov_iter *to)
 {
 	ssize_t rc = 0;
 
 	mutex_lock(&test_fw_mutex);
 	if (test_firmware)
-		rc = simple_read_from_buffer(buf, size, offset,
-					     test_firmware->data,
-					     test_firmware->size);
+		rc = simple_copy_to_iter(test_firmware->data, &iocb->ki_pos,
+					     test_firmware->size, to);
 	mutex_unlock(&test_fw_mutex);
 	return rc;
 }
 
 static const struct file_operations test_fw_fops = {
 	.owner          = THIS_MODULE,
-	.read           = test_fw_misc_read,
+	.read_iter      = test_fw_misc_read,
 };
 
 static void __test_release_all_firmware(void)
diff --git a/lib/xz/xz_dec_test.c b/lib/xz/xz_dec_test.c
index da28a19d6c98..42dc077e247b 100644
--- a/lib/xz/xz_dec_test.c
+++ b/lib/xz/xz_dec_test.c
@@ -99,9 +99,9 @@ static int xz_dec_test_release(struct inode *i, struct file *f)
  * The .xz file must have exactly one Stream and no Stream Padding. The data
  * after the first Stream is considered to be garbage.
  */
-static ssize_t xz_dec_test_write(struct file *file, const char __user *buf,
-				 size_t size, loff_t *pos)
+static ssize_t xz_dec_test_write(struct kiocb *iocb, struct iov_iter *from)
 {
+	size_t size = iov_iter_count(from);
 	size_t remaining;
 
 	if (ret != XZ_OK) {
@@ -122,10 +122,9 @@ static ssize_t xz_dec_test_write(struct file *file, const char __user *buf,
 		if (buffers.in_pos == buffers.in_size) {
 			buffers.in_pos = 0;
 			buffers.in_size = min(remaining, sizeof(buffer_in));
-			if (copy_from_user(buffer_in, buf, buffers.in_size))
+			if (!copy_from_iter_full(buffer_in, buffers.in_size, from))
 				return -EFAULT;
 
-			buf += buffers.in_size;
 			remaining -= buffers.in_size;
 		}
 
@@ -179,7 +178,7 @@ static int __init xz_dec_test_init(void)
 		.owner = THIS_MODULE,
 		.open = &xz_dec_test_open,
 		.release = &xz_dec_test_release,
-		.write = &xz_dec_test_write
+		.write_iter = &xz_dec_test_write
 	};
 
 	state = xz_dec_init(XZ_PREALLOC, DICT_MAX);
-- 
2.43.0