[PATCH 339/437] powerpc/spufs: convert to read/write iterators

[Jens Axboe]

Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
---
 arch/powerpc/platforms/cell/spufs/file.c | 312 +++++++++++------------
 1 file changed, 147 insertions(+), 165 deletions(-)

diff --git a/arch/powerpc/platforms/cell/spufs/file.c b/arch/powerpc/platforms/cell/spufs/file.c
index 02a8158c469d..025c9b0a0470 100644
--- a/arch/powerpc/platforms/cell/spufs/file.c
+++ b/arch/powerpc/platforms/cell/spufs/file.c
@@ -67,14 +67,13 @@ static int spufs_attr_release(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static ssize_t spufs_attr_read(struct file *file, char __user *buf,
-		size_t len, loff_t *ppos)
+static ssize_t spufs_attr_read(struct kiocb *iocb, struct iov_iter *to)
 {
 	struct spufs_attr *attr;
 	size_t size;
 	ssize_t ret;
 
-	attr = file->private_data;
+	attr = iocb->ki_filp->private_data;
 	if (!attr->get)
 		return -EACCES;
 
@@ -82,7 +81,7 @@ static ssize_t spufs_attr_read(struct file *file, char __user *buf,
 	if (ret)
 		return ret;
 
-	if (*ppos) {		/* continued read */
+	if (iocb->ki_pos) {	/* continued read */
 		size = strlen(attr->get_buf);
 	} else {		/* first read */
 		u64 val;
@@ -94,21 +93,21 @@ static ssize_t spufs_attr_read(struct file *file, char __user *buf,
 				 attr->fmt, (unsigned long long)val);
 	}
 
-	ret = simple_read_from_buffer(buf, len, ppos, attr->get_buf, size);
+	ret = simple_copy_to_iter(attr->get_buf, &iocb->ki_pos, size, to);
 out:
 	mutex_unlock(&attr->mutex);
 	return ret;
 }
 
-static ssize_t spufs_attr_write(struct file *file, const char __user *buf,
-		size_t len, loff_t *ppos)
+static ssize_t spufs_attr_write(struct kiocb *iocb, struct iov_iter *from)
 {
+	size_t len = iov_iter_count(from);
 	struct spufs_attr *attr;
 	u64 val;
 	size_t size;
 	ssize_t ret;
 
-	attr = file->private_data;
+	attr = iocb->ki_filp->private_data;
 	if (!attr->set)
 		return -EACCES;
 
@@ -118,7 +117,7 @@ static ssize_t spufs_attr_write(struct file *file, const char __user *buf,
 
 	ret = -EFAULT;
 	size = min(sizeof(attr->set_buf) - 1, len);
-	if (copy_from_user(attr->set_buf, buf, size))
+	if (!copy_from_iter_full(attr->set_buf, size, from))
 		goto out;
 
 	ret = len; /* claim we got the whole input */
@@ -147,8 +146,8 @@ static int __fops ## _open(struct inode *inode, struct file *file)	\
 static const struct file_operations __fops = {				\
 	.open	 = __fops ## _open,					\
 	.release = spufs_attr_release,					\
-	.read	 = spufs_attr_read,					\
-	.write	 = spufs_attr_write,					\
+	.read_iter = spufs_attr_read,					\
+	.write_iter = spufs_attr_write,					\
 	.llseek  = generic_file_llseek,					\
 };
 
@@ -186,30 +185,27 @@ spufs_mem_dump(struct spu_context *ctx, struct coredump_params *cprm)
 	return spufs_dump_emit(cprm, ctx->ops->get_ls(ctx), LS_SIZE);
 }
 
-static ssize_t
-spufs_mem_read(struct file *file, char __user *buffer,
-				size_t size, loff_t *pos)
+static ssize_t spufs_mem_read(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
 	ssize_t ret;
 
 	ret = spu_acquire(ctx);
 	if (ret)
 		return ret;
-	ret = simple_read_from_buffer(buffer, size, pos, ctx->ops->get_ls(ctx),
-				      LS_SIZE);
+	ret = simple_copy_to_iter(ctx->ops->get_ls(ctx), &iocb->ki_pos, LS_SIZE,
+				  to);
 	spu_release(ctx);
 
 	return ret;
 }
 
-static ssize_t
-spufs_mem_write(struct file *file, const char __user *buffer,
-					size_t size, loff_t *ppos)
+static ssize_t spufs_mem_write(struct kiocb *iocb, struct iov_iter *from)
 {
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
 	char *local_store;
-	loff_t pos = *ppos;
+	loff_t pos = iocb->ki_pos;
+	ssize_t size;
 	int ret;
 
 	if (pos > LS_SIZE)
@@ -220,7 +216,7 @@ spufs_mem_write(struct file *file, const char __user *buffer,
 		return ret;
 
 	local_store = ctx->ops->get_ls(ctx);
-	size = simple_write_to_buffer(local_store, LS_SIZE, ppos, buffer, size);
+	size = simple_copy_to_iter(local_store, &iocb->ki_pos, LS_SIZE, from);
 	spu_release(ctx);
 
 	return size;
@@ -301,8 +297,8 @@ static int spufs_mem_mmap(struct file *file, struct vm_area_struct *vma)
 static const struct file_operations spufs_mem_fops = {
 	.open			= spufs_mem_open,
 	.release		= spufs_mem_release,
-	.read			= spufs_mem_read,
-	.write			= spufs_mem_write,
+	.read_iter		= spufs_mem_read,
+	.write_iter		= spufs_mem_write,
 	.llseek			= generic_file_llseek,
 	.mmap			= spufs_mem_mmap,
 };
@@ -451,8 +447,8 @@ spufs_cntl_release(struct inode *inode, struct file *file)
 static const struct file_operations spufs_cntl_fops = {
 	.open = spufs_cntl_open,
 	.release = spufs_cntl_release,
-	.read = simple_attr_read,
-	.write = simple_attr_write,
+	.read_iter = simple_attr_read_iter,
+	.write_iter = simple_attr_write_iter,
 	.llseek	= no_llseek,
 	.mmap = spufs_cntl_mmap,
 };
@@ -472,44 +468,41 @@ spufs_regs_dump(struct spu_context *ctx, struct coredump_params *cprm)
 			       sizeof(ctx->csa.lscsa->gprs));
 }
 
-static ssize_t
-spufs_regs_read(struct file *file, char __user *buffer,
-		size_t size, loff_t *pos)
+static ssize_t spufs_regs_read(struct kiocb *iocb, struct iov_iter *to)
 {
 	int ret;
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
 
 	/* pre-check for file position: if we'd return EOF, there's no point
 	 * causing a deschedule */
-	if (*pos >= sizeof(ctx->csa.lscsa->gprs))
+	if (iocb->ki_pos >= sizeof(ctx->csa.lscsa->gprs))
 		return 0;
 
 	ret = spu_acquire_saved(ctx);
 	if (ret)
 		return ret;
-	ret = simple_read_from_buffer(buffer, size, pos, ctx->csa.lscsa->gprs,
-				      sizeof(ctx->csa.lscsa->gprs));
+	ret = simple_copy_to_iter(ctx->csa.lscsa->gprs, &iocb->ki_pos,
+				      sizeof(ctx->csa.lscsa->gprs), to);
 	spu_release_saved(ctx);
 	return ret;
 }
 
-static ssize_t
-spufs_regs_write(struct file *file, const char __user *buffer,
-		 size_t size, loff_t *pos)
+static ssize_t spufs_regs_write(struct kiocb *iocb, struct iov_iter *from)
 {
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
 	struct spu_lscsa *lscsa = ctx->csa.lscsa;
+	ssize_t size;
 	int ret;
 
-	if (*pos >= sizeof(lscsa->gprs))
+	if (iocb->ki_pos >= sizeof(lscsa->gprs))
 		return -EFBIG;
 
 	ret = spu_acquire_saved(ctx);
 	if (ret)
 		return ret;
 
-	size = simple_write_to_buffer(lscsa->gprs, sizeof(lscsa->gprs), pos,
-					buffer, size);
+	size = simple_copy_from_iter(lscsa->gprs, &iocb->ki_pos,
+					sizeof(lscsa->gprs), from);
 
 	spu_release_saved(ctx);
 	return size;
@@ -517,8 +510,8 @@ spufs_regs_write(struct file *file, const char __user *buffer,
 
 static const struct file_operations spufs_regs_fops = {
 	.open	 = spufs_regs_open,
-	.read    = spufs_regs_read,
-	.write   = spufs_regs_write,
+	.read_iter = spufs_regs_read,
+	.write_iter = spufs_regs_write,
 	.llseek  = generic_file_llseek,
 };
 
@@ -529,39 +522,36 @@ spufs_fpcr_dump(struct spu_context *ctx, struct coredump_params *cprm)
 			       sizeof(ctx->csa.lscsa->fpcr));
 }
 
-static ssize_t
-spufs_fpcr_read(struct file *file, char __user * buffer,
-		size_t size, loff_t * pos)
+static ssize_t spufs_fpcr_read(struct kiocb *iocb, struct iov_iter *to)
 {
 	int ret;
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
 
 	ret = spu_acquire_saved(ctx);
 	if (ret)
 		return ret;
-	ret = simple_read_from_buffer(buffer, size, pos, &ctx->csa.lscsa->fpcr,
-				      sizeof(ctx->csa.lscsa->fpcr));
+	ret = simple_copy_to_iter(&ctx->csa.lscsa->fpcr, &iocb->ki_pos,
+				      sizeof(ctx->csa.lscsa->fpcr), to);
 	spu_release_saved(ctx);
 	return ret;
 }
 
-static ssize_t
-spufs_fpcr_write(struct file *file, const char __user * buffer,
-		 size_t size, loff_t * pos)
+static ssize_t spufs_fpcr_write(struct kiocb *iocb, struct iov_iter *from)
 {
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
 	struct spu_lscsa *lscsa = ctx->csa.lscsa;
+	ssize_t size;
 	int ret;
 
-	if (*pos >= sizeof(lscsa->fpcr))
+	if (iocb->ki_pos >= sizeof(lscsa->fpcr))
 		return -EFBIG;
 
 	ret = spu_acquire_saved(ctx);
 	if (ret)
 		return ret;
 
-	size = simple_write_to_buffer(&lscsa->fpcr, sizeof(lscsa->fpcr), pos,
-					buffer, size);
+	size = simple_copy_from_iter(&lscsa->fpcr, &iocb->ki_pos,
+					sizeof(lscsa->fpcr), from);
 
 	spu_release_saved(ctx);
 	return size;
@@ -569,8 +559,8 @@ spufs_fpcr_write(struct file *file, const char __user * buffer,
 
 static const struct file_operations spufs_fpcr_fops = {
 	.open = spufs_regs_open,
-	.read = spufs_fpcr_read,
-	.write = spufs_fpcr_write,
+	.read_iter = spufs_fpcr_read,
+	.write_iter = spufs_fpcr_write,
 	.llseek = generic_file_llseek,
 };
 
@@ -591,11 +581,11 @@ static int spufs_pipe_open(struct inode *inode, struct file *file)
  * - end of the user provided buffer
  * - end of the mapped area
  */
-static ssize_t spufs_mbox_read(struct file *file, char __user *buf,
-			size_t len, loff_t *pos)
+static ssize_t spufs_mbox_read(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct spu_context *ctx = file->private_data;
-	u32 mbox_data, __user *udata = (void __user *)buf;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
+	size_t len = iov_iter_count(to);
+	u32 mbox_data;
 	ssize_t count;
 
 	if (len < 4)
@@ -605,7 +595,7 @@ static ssize_t spufs_mbox_read(struct file *file, char __user *buf,
 	if (count)
 		return count;
 
-	for (count = 0; (count + 4) <= len; count += 4, udata++) {
+	for (count = 0; (count + 4) <= len; count += 4) {
 		int ret;
 		ret = ctx->ops->mbox_read(ctx, &mbox_data);
 		if (ret == 0)
@@ -616,7 +606,7 @@ static ssize_t spufs_mbox_read(struct file *file, char __user *buf,
 		 * but still need to return the data we have
 		 * read successfully so far.
 		 */
-		ret = put_user(mbox_data, udata);
+		ret = put_iter(mbox_data, to);
 		if (ret) {
 			if (!count)
 				count = -EFAULT;
@@ -633,14 +623,14 @@ static ssize_t spufs_mbox_read(struct file *file, char __user *buf,
 
 static const struct file_operations spufs_mbox_fops = {
 	.open	= spufs_pipe_open,
-	.read	= spufs_mbox_read,
+	.read_iter = spufs_mbox_read,
 	.llseek	= no_llseek,
 };
 
-static ssize_t spufs_mbox_stat_read(struct file *file, char __user *buf,
-			size_t len, loff_t *pos)
+static ssize_t spufs_mbox_stat_read(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
+	size_t len = iov_iter_count(to);
 	ssize_t ret;
 	u32 mbox_stat;
 
@@ -655,7 +645,7 @@ static ssize_t spufs_mbox_stat_read(struct file *file, char __user *buf,
 
 	spu_release(ctx);
 
-	if (copy_to_user(buf, &mbox_stat, sizeof mbox_stat))
+	if (!copy_to_iter_full(&mbox_stat, sizeof (mbox_stat), to))
 		return -EFAULT;
 
 	return 4;
@@ -663,7 +653,7 @@ static ssize_t spufs_mbox_stat_read(struct file *file, char __user *buf,
 
 static const struct file_operations spufs_mbox_stat_fops = {
 	.open	= spufs_pipe_open,
-	.read	= spufs_mbox_stat_read,
+	.read_iter = spufs_mbox_stat_read,
 	.llseek = no_llseek,
 };
 
@@ -694,11 +684,11 @@ void spufs_ibox_callback(struct spu *spu)
  * any data is available, but return when we have been able to
  * read something.
  */
-static ssize_t spufs_ibox_read(struct file *file, char __user *buf,
-			size_t len, loff_t *pos)
+static ssize_t spufs_ibox_read(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct spu_context *ctx = file->private_data;
-	u32 ibox_data, __user *udata = (void __user *)buf;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
+	size_t len = iov_iter_count(to);
+	u32 ibox_data;
 	ssize_t count;
 
 	if (len < 4)
@@ -710,7 +700,7 @@ static ssize_t spufs_ibox_read(struct file *file, char __user *buf,
 
 	/* wait only for the first element */
 	count = 0;
-	if (file->f_flags & O_NONBLOCK) {
+	if (iocb->ki_filp->f_flags & O_NONBLOCK) {
 		if (!spu_ibox_read(ctx, &ibox_data)) {
 			count = -EAGAIN;
 			goto out_unlock;
@@ -722,11 +712,11 @@ static ssize_t spufs_ibox_read(struct file *file, char __user *buf,
 	}
 
 	/* if we can't write at all, return -EFAULT */
-	count = put_user(ibox_data, udata);
+	count = put_iter(ibox_data, to);
 	if (count)
 		goto out_unlock;
 
-	for (count = 4, udata++; (count + 4) <= len; count += 4, udata++) {
+	for (count = 4; (count + 4) <= len; count += 4) {
 		int ret;
 		ret = ctx->ops->ibox_read(ctx, &ibox_data);
 		if (ret == 0)
@@ -736,7 +726,7 @@ static ssize_t spufs_ibox_read(struct file *file, char __user *buf,
 		 * but still need to return the data we have
 		 * read successfully so far.
 		 */
-		ret = put_user(ibox_data, udata);
+		ret = put_iter(ibox_data, to);
 		if (ret)
 			break;
 	}
@@ -767,15 +757,15 @@ static __poll_t spufs_ibox_poll(struct file *file, poll_table *wait)
 
 static const struct file_operations spufs_ibox_fops = {
 	.open	= spufs_pipe_open,
-	.read	= spufs_ibox_read,
+	.read_iter = spufs_ibox_read,
 	.poll	= spufs_ibox_poll,
 	.llseek = no_llseek,
 };
 
-static ssize_t spufs_ibox_stat_read(struct file *file, char __user *buf,
-			size_t len, loff_t *pos)
+static ssize_t spufs_ibox_stat_read(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
+	size_t len = iov_iter_count(to);
 	ssize_t ret;
 	u32 ibox_stat;
 
@@ -788,7 +778,7 @@ static ssize_t spufs_ibox_stat_read(struct file *file, char __user *buf,
 	ibox_stat = (ctx->ops->mbox_stat_read(ctx) >> 16) & 0xff;
 	spu_release(ctx);
 
-	if (copy_to_user(buf, &ibox_stat, sizeof ibox_stat))
+	if (!copy_to_iter_full(&ibox_stat, sizeof ibox_stat, to))
 		return -EFAULT;
 
 	return 4;
@@ -796,7 +786,7 @@ static ssize_t spufs_ibox_stat_read(struct file *file, char __user *buf,
 
 static const struct file_operations spufs_ibox_stat_fops = {
 	.open	= spufs_pipe_open,
-	.read	= spufs_ibox_stat_read,
+	.read_iter = spufs_ibox_stat_read,
 	.llseek = no_llseek,
 };
 
@@ -827,17 +817,17 @@ void spufs_wbox_callback(struct spu *spu)
  * space is available, but return when we have been able to
  * write something.
  */
-static ssize_t spufs_wbox_write(struct file *file, const char __user *buf,
-			size_t len, loff_t *pos)
+static ssize_t spufs_wbox_write(struct kiocb *iocb, struct iov_iter *from)
 {
-	struct spu_context *ctx = file->private_data;
-	u32 wbox_data, __user *udata = (void __user *)buf;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
+	size_t len = iov_iter_count(from);
+	u32 wbox_data;
 	ssize_t count;
 
 	if (len < 4)
 		return -EINVAL;
 
-	if (get_user(wbox_data, udata))
+	if (get_iter(wbox_data, from))
 		return -EFAULT;
 
 	count = spu_acquire(ctx);
@@ -849,7 +839,7 @@ static ssize_t spufs_wbox_write(struct file *file, const char __user *buf,
 	 * in case of !O_NONBLOCK
 	 */
 	count = 0;
-	if (file->f_flags & O_NONBLOCK) {
+	if (iocb->ki_filp->f_flags & O_NONBLOCK) {
 		if (!spu_wbox_write(ctx, wbox_data)) {
 			count = -EAGAIN;
 			goto out_unlock;
@@ -862,9 +852,9 @@ static ssize_t spufs_wbox_write(struct file *file, const char __user *buf,
 
 
 	/* write as much as possible */
-	for (count = 4, udata++; (count + 4) <= len; count += 4, udata++) {
+	for (count = 4; (count + 4) <= len; count += 4) {
 		int ret;
-		ret = get_user(wbox_data, udata);
+		ret = get_iter(wbox_data, from);
 		if (ret)
 			break;
 
@@ -899,15 +889,15 @@ static __poll_t spufs_wbox_poll(struct file *file, poll_table *wait)
 
 static const struct file_operations spufs_wbox_fops = {
 	.open	= spufs_pipe_open,
-	.write	= spufs_wbox_write,
+	.write_iter = spufs_wbox_write,
 	.poll	= spufs_wbox_poll,
 	.llseek = no_llseek,
 };
 
-static ssize_t spufs_wbox_stat_read(struct file *file, char __user *buf,
-			size_t len, loff_t *pos)
+static ssize_t spufs_wbox_stat_read(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
+	size_t len = iov_iter_count(to);
 	ssize_t ret;
 	u32 wbox_stat;
 
@@ -920,7 +910,7 @@ static ssize_t spufs_wbox_stat_read(struct file *file, char __user *buf,
 	wbox_stat = (ctx->ops->mbox_stat_read(ctx) >> 8) & 0xff;
 	spu_release(ctx);
 
-	if (copy_to_user(buf, &wbox_stat, sizeof wbox_stat))
+	if (!copy_to_iter_full(&wbox_stat, sizeof wbox_stat, to))
 		return -EFAULT;
 
 	return 4;
@@ -928,7 +918,7 @@ static ssize_t spufs_wbox_stat_read(struct file *file, char __user *buf,
 
 static const struct file_operations spufs_wbox_stat_fops = {
 	.open	= spufs_pipe_open,
-	.read	= spufs_wbox_stat_read,
+	.read_iter = spufs_wbox_stat_read,
 	.llseek = no_llseek,
 };
 
@@ -994,6 +984,7 @@ static ssize_t spufs_signal1_read(struct file *file, char __user *buf,
 
 	return ret;
 }
+FOPS_READ_ITER_HELPER(spufs_signal1_read);
 
 static ssize_t spufs_signal1_write(struct file *file, const char __user *buf,
 			size_t len, loff_t *pos)
@@ -1018,6 +1009,7 @@ static ssize_t spufs_signal1_write(struct file *file, const char __user *buf,
 
 	return 4;
 }
+FOPS_WRITE_ITER_HELPER(spufs_signal1_write);
 
 static vm_fault_t
 spufs_signal1_mmap_fault(struct vm_fault *vmf)
@@ -1053,8 +1045,8 @@ static int spufs_signal1_mmap(struct file *file, struct vm_area_struct *vma)
 static const struct file_operations spufs_signal1_fops = {
 	.open = spufs_signal1_open,
 	.release = spufs_signal1_release,
-	.read = spufs_signal1_read,
-	.write = spufs_signal1_write,
+	.read_iter = spufs_signal1_read_iter,
+	.write_iter = spufs_signal1_write_iter,
 	.mmap = spufs_signal1_mmap,
 	.llseek = no_llseek,
 };
@@ -1062,7 +1054,7 @@ static const struct file_operations spufs_signal1_fops = {
 static const struct file_operations spufs_signal1_nosched_fops = {
 	.open = spufs_signal1_open,
 	.release = spufs_signal1_release,
-	.write = spufs_signal1_write,
+	.write_iter = spufs_signal1_write_iter,
 	.mmap = spufs_signal1_mmap,
 	.llseek = no_llseek,
 };
@@ -1102,29 +1094,28 @@ static ssize_t spufs_signal2_dump(struct spu_context *ctx,
 			       sizeof(ctx->csa.spu_chnldata_RW[4]));
 }
 
-static ssize_t __spufs_signal2_read(struct spu_context *ctx, char __user *buf,
-			size_t len)
+static ssize_t __spufs_signal2_read(struct spu_context *ctx, struct iov_iter *to)
 {
+	size_t len = iov_iter_count(to);
 	if (len < sizeof(ctx->csa.spu_chnldata_RW[4]))
 		return -EINVAL;
 	if (!ctx->csa.spu_chnlcnt_RW[4])
 		return 0;
-	if (copy_to_user(buf, &ctx->csa.spu_chnldata_RW[4],
-			 sizeof(ctx->csa.spu_chnldata_RW[4])))
+	if (!copy_to_iter_full(&ctx->csa.spu_chnldata_RW[4],
+			 sizeof(ctx->csa.spu_chnldata_RW[4]), to))
 		return -EFAULT;
 	return sizeof(ctx->csa.spu_chnldata_RW[4]);
 }
 
-static ssize_t spufs_signal2_read(struct file *file, char __user *buf,
-			size_t len, loff_t *pos)
+static ssize_t spufs_signal2_read(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
 	int ret;
 
 	ret = spu_acquire_saved(ctx);
 	if (ret)
 		return ret;
-	ret = __spufs_signal2_read(ctx, buf, len);
+	ret = __spufs_signal2_read(ctx, to);
 	spu_release_saved(ctx);
 
 	return ret;
@@ -1153,6 +1144,7 @@ static ssize_t spufs_signal2_write(struct file *file, const char __user *buf,
 
 	return 4;
 }
+FOPS_WRITE_ITER_HELPER(spufs_signal2_write);
 
 #if SPUFS_MMAP_4K
 static vm_fault_t
@@ -1192,8 +1184,8 @@ static int spufs_signal2_mmap(struct file *file, struct vm_area_struct *vma)
 static const struct file_operations spufs_signal2_fops = {
 	.open = spufs_signal2_open,
 	.release = spufs_signal2_release,
-	.read = spufs_signal2_read,
-	.write = spufs_signal2_write,
+	.read_iter = spufs_signal2_read,
+	.write_iter = spufs_signal2_write_iter,
 	.mmap = spufs_signal2_mmap,
 	.llseek = no_llseek,
 };
@@ -1201,7 +1193,7 @@ static const struct file_operations spufs_signal2_fops = {
 static const struct file_operations spufs_signal2_nosched_fops = {
 	.open = spufs_signal2_open,
 	.release = spufs_signal2_release,
-	.write = spufs_signal2_write,
+	.write_iter = spufs_signal2_write_iter,
 	.mmap = spufs_signal2_mmap,
 	.llseek = no_llseek,
 };
@@ -1491,10 +1483,10 @@ static int spufs_read_mfc_tagstatus(struct spu_context *ctx, u32 *status)
 	return 0;
 }
 
-static ssize_t spufs_mfc_read(struct file *file, char __user *buffer,
-			size_t size, loff_t *pos)
+static ssize_t spufs_mfc_read(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
+	size_t size = iov_iter_count(to);
 	int ret = -EINVAL;
 	u32 status;
 
@@ -1506,7 +1498,7 @@ static ssize_t spufs_mfc_read(struct file *file, char __user *buffer,
 		return ret;
 
 	ret = -EINVAL;
-	if (file->f_flags & O_NONBLOCK) {
+	if (iocb->ki_filp->f_flags & O_NONBLOCK) {
 		status = ctx->ops->read_mfc_tagstatus(ctx);
 		if (!(status & ctx->tagwait))
 			ret = -EAGAIN;
@@ -1522,7 +1514,7 @@ static ssize_t spufs_mfc_read(struct file *file, char __user *buffer,
 	spu_release(ctx);
 
 	ret = 4;
-	if (copy_to_user(buffer, &status, 4))
+	if (!copy_to_iter_full(&status, 4, to))
 		ret = -EFAULT;
 
 out:
@@ -1617,10 +1609,10 @@ static int spu_send_mfc_command(struct spu_context *ctx,
 	return 1;
 }
 
-static ssize_t spufs_mfc_write(struct file *file, const char __user *buffer,
-			size_t size, loff_t *pos)
+static ssize_t spufs_mfc_write(struct kiocb *iocb, struct iov_iter *from)
 {
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
+	size_t size = iov_iter_count(from);
 	struct mfc_dma_command cmd;
 	int ret = -EINVAL;
 
@@ -1628,7 +1620,7 @@ static ssize_t spufs_mfc_write(struct file *file, const char __user *buffer,
 		goto out;
 
 	ret = -EFAULT;
-	if (copy_from_user(&cmd, buffer, sizeof cmd))
+	if (!copy_from_iter_full(&cmd, sizeof cmd, from))
 		goto out;
 
 	ret = spufs_check_valid_dma(&cmd);
@@ -1643,7 +1635,7 @@ static ssize_t spufs_mfc_write(struct file *file, const char __user *buffer,
 	if (ret)
 		goto out;
 
-	if (file->f_flags & O_NONBLOCK) {
+	if (iocb->ki_filp->f_flags & O_NONBLOCK) {
 		ret = ctx->ops->send_mfc_command(ctx, &cmd);
 	} else {
 		int status;
@@ -1738,8 +1730,8 @@ static int spufs_mfc_fsync(struct file *file, loff_t start, loff_t end, int data
 static const struct file_operations spufs_mfc_fops = {
 	.open	 = spufs_mfc_open,
 	.release = spufs_mfc_release,
-	.read	 = spufs_mfc_read,
-	.write	 = spufs_mfc_write,
+	.read_iter = spufs_mfc_read,
+	.write_iter = spufs_mfc_write,
 	.poll	 = spufs_mfc_poll,
 	.flush	 = spufs_mfc_flush,
 	.fsync	 = spufs_mfc_fsync,
@@ -1943,7 +1935,7 @@ static int spufs_caps_open(struct inode *inode, struct file *file)
 
 static const struct file_operations spufs_caps_fops = {
 	.open		= spufs_caps_open,
-	.read		= seq_read,
+	.read_iter	= seq_read_iter,
 	.llseek		= seq_lseek,
 	.release	= single_release,
 };
@@ -1957,10 +1949,9 @@ static ssize_t spufs_mbox_info_dump(struct spu_context *ctx,
 			       sizeof(ctx->csa.prob.pu_mb_R));
 }
 
-static ssize_t spufs_mbox_info_read(struct file *file, char __user *buf,
-				   size_t len, loff_t *pos)
+static ssize_t spufs_mbox_info_read(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
 	u32 stat, data;
 	int ret;
 
@@ -1977,12 +1968,12 @@ static ssize_t spufs_mbox_info_read(struct file *file, char __user *buf,
 	if (!(stat & 0x0000ff))
 		return 0;
 
-	return simple_read_from_buffer(buf, len, pos, &data, sizeof(data));
+	return simple_copy_to_iter(&data, &iocb->ki_pos, sizeof(data), to);
 }
 
 static const struct file_operations spufs_mbox_info_fops = {
 	.open = spufs_info_open,
-	.read = spufs_mbox_info_read,
+	.read_iter = spufs_mbox_info_read,
 	.llseek  = generic_file_llseek,
 };
 
@@ -1995,10 +1986,9 @@ static ssize_t spufs_ibox_info_dump(struct spu_context *ctx,
 			       sizeof(ctx->csa.priv2.puint_mb_R));
 }
 
-static ssize_t spufs_ibox_info_read(struct file *file, char __user *buf,
-				   size_t len, loff_t *pos)
+static ssize_t spufs_ibox_info_read(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
 	u32 stat, data;
 	int ret;
 
@@ -2015,12 +2005,12 @@ static ssize_t spufs_ibox_info_read(struct file *file, char __user *buf,
 	if (!(stat & 0xff0000))
 		return 0;
 
-	return simple_read_from_buffer(buf, len, pos, &data, sizeof(data));
+	return simple_copy_to_iter(&data, &iocb->ki_pos, sizeof(data), to);
 }
 
 static const struct file_operations spufs_ibox_info_fops = {
 	.open = spufs_info_open,
-	.read = spufs_ibox_info_read,
+	.read_iter = spufs_ibox_info_read,
 	.llseek  = generic_file_llseek,
 };
 
@@ -2036,10 +2026,9 @@ static ssize_t spufs_wbox_info_dump(struct spu_context *ctx,
 			spufs_wbox_info_cnt(ctx));
 }
 
-static ssize_t spufs_wbox_info_read(struct file *file, char __user *buf,
-				   size_t len, loff_t *pos)
+static ssize_t spufs_wbox_info_read(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
 	u32 data[ARRAY_SIZE(ctx->csa.spu_mailbox_data)];
 	int ret, count;
 
@@ -2052,13 +2041,12 @@ static ssize_t spufs_wbox_info_read(struct file *file, char __user *buf,
 	spin_unlock(&ctx->csa.register_lock);
 	spu_release_saved(ctx);
 
-	return simple_read_from_buffer(buf, len, pos, &data,
-				count * sizeof(u32));
+	return simple_copy_to_iter(&data, &iocb->ki_pos, count * sizeof(u32), to);
 }
 
 static const struct file_operations spufs_wbox_info_fops = {
 	.open = spufs_info_open,
-	.read = spufs_wbox_info_read,
+	.read_iter = spufs_wbox_info_read,
 	.llseek  = generic_file_llseek,
 };
 
@@ -2092,10 +2080,9 @@ static ssize_t spufs_dma_info_dump(struct spu_context *ctx,
 	return spufs_dump_emit(cprm, &info, sizeof(info));
 }
 
-static ssize_t spufs_dma_info_read(struct file *file, char __user *buf,
-			      size_t len, loff_t *pos)
+static ssize_t spufs_dma_info_read(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
 	struct spu_dma_info info;
 	int ret;
 
@@ -2107,13 +2094,12 @@ static ssize_t spufs_dma_info_read(struct file *file, char __user *buf,
 	spin_unlock(&ctx->csa.register_lock);
 	spu_release_saved(ctx);
 
-	return simple_read_from_buffer(buf, len, pos, &info,
-				sizeof(info));
+	return simple_copy_to_iter(&info, &iocb->ki_pos, sizeof(info), to);
 }
 
 static const struct file_operations spufs_dma_info_fops = {
 	.open = spufs_info_open,
-	.read = spufs_dma_info_read,
+	.read_iter = spufs_dma_info_read,
 	.llseek = no_llseek,
 };
 
@@ -2146,10 +2132,10 @@ static ssize_t spufs_proxydma_info_dump(struct spu_context *ctx,
 	return spufs_dump_emit(cprm, &info, sizeof(info));
 }
 
-static ssize_t spufs_proxydma_info_read(struct file *file, char __user *buf,
-				   size_t len, loff_t *pos)
+static ssize_t spufs_proxydma_info_read(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct spu_context *ctx = file->private_data;
+	struct spu_context *ctx = iocb->ki_filp->private_data;
+	size_t len = iov_iter_count(to);
 	struct spu_proxydma_info info;
 	int ret;
 
@@ -2164,13 +2150,12 @@ static ssize_t spufs_proxydma_info_read(struct file *file, char __user *buf,
 	spin_unlock(&ctx->csa.register_lock);
 	spu_release_saved(ctx);
 
-	return simple_read_from_buffer(buf, len, pos, &info,
-				sizeof(info));
+	return simple_copy_to_iter(&info, &iocb->ki_pos, sizeof(info), to);
 }
 
 static const struct file_operations spufs_proxydma_info_fops = {
 	.open = spufs_info_open,
-	.read = spufs_proxydma_info_read,
+	.read_iter = spufs_proxydma_info_read,
 	.llseek = no_llseek,
 };
 
@@ -2189,7 +2174,7 @@ static int spufs_tid_open(struct inode *inode, struct file *file)
 
 static const struct file_operations spufs_tid_fops = {
 	.open		= spufs_tid_open,
-	.read		= seq_read,
+	.read_iter	= seq_read_iter,
 	.llseek		= seq_lseek,
 	.release	= single_release,
 };
@@ -2279,7 +2264,7 @@ static int spufs_stat_open(struct inode *inode, struct file *file)
 
 static const struct file_operations spufs_stat_fops = {
 	.open		= spufs_stat_open,
-	.read		= seq_read,
+	.read_iter	= seq_read_iter,
 	.llseek		= seq_lseek,
 	.release	= single_release,
 };
@@ -2357,16 +2342,13 @@ static int switch_log_sprint(struct spu_context *ctx, char *tbuf, int n)
 			(unsigned long long) p->timebase);
 }
 
-static ssize_t spufs_switch_log_read(struct file *file, char __user *buf,
-			     size_t len, loff_t *ppos)
+static ssize_t spufs_switch_log_read(struct kiocb *iocb, struct iov_iter *to)
 {
-	struct inode *inode = file_inode(file);
+	struct inode *inode = file_inode(iocb->ki_filp);
 	struct spu_context *ctx = SPUFS_I(inode)->i_ctx;
+	size_t len = iov_iter_count(to);
 	int error = 0, cnt = 0;
 
-	if (!buf)
-		return -EINVAL;
-
 	error = spu_acquire(ctx);
 	if (error)
 		return error;
@@ -2381,7 +2363,7 @@ static ssize_t spufs_switch_log_read(struct file *file, char __user *buf,
 				 * just return straight away */
 				break;
 
-			} else if (file->f_flags & O_NONBLOCK) {
+			} else if (iocb->ki_filp->f_flags & O_NONBLOCK) {
 				error = -EAGAIN;
 				break;
 
@@ -2417,7 +2399,7 @@ static ssize_t spufs_switch_log_read(struct file *file, char __user *buf,
 			 * partial buffer (so far) */
 			break;
 
-		error = copy_to_user(buf + cnt, tbuf, width);
+		error = !copy_to_iter_full(tbuf, width, to);
 		if (error)
 			break;
 		cnt += width;
@@ -2451,7 +2433,7 @@ static __poll_t spufs_switch_log_poll(struct file *file, poll_table *wait)
 
 static const struct file_operations spufs_switch_log_fops = {
 	.open		= spufs_switch_log_open,
-	.read		= spufs_switch_log_read,
+	.read_iter	= spufs_switch_log_read,
 	.poll		= spufs_switch_log_poll,
 	.release	= spufs_switch_log_release,
 	.llseek		= no_llseek,
@@ -2532,7 +2514,7 @@ static int spufs_ctx_open(struct inode *inode, struct file *file)
 
 static const struct file_operations spufs_ctx_fops = {
 	.open           = spufs_ctx_open,
-	.read           = seq_read,
+	.read_iter      = seq_read_iter,
 	.llseek         = seq_lseek,
 	.release        = single_release,
 };
-- 
2.43.0