[rh7] ms/aio: Kill aio_rw_vect_retry()

Submitted by Andrey Ryabinin on Oct. 14, 2020, 8:03 a.m.

Details

Message ID 20201014080343.20191-1-aryabinin@virtuozzo.com
State New
Series "ms/aio: Kill aio_rw_vect_retry()"
Headers show

Commit Message

Andrey Ryabinin Oct. 14, 2020, 8:03 a.m.
From: Kent Overstreet <koverstreet@google.com>

This code doesn't serve any purpose anymore, since the aio retry
infrastructure has been removed.

This change should be safe because aio_read/write are also used for
synchronous IO, and called from do_sync_read()/do_sync_write() - and
there's no looping done in the sync case (the read and write syscalls).

Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: Zach Brown <zab@redhat.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Signed-off-by: Benjamin LaHaise <bcrl@kvack.org>

https://jira.sw.ru/browse/PSBM-121197
(cherry picked from commit 73a7075e3f6ec63dc359064eea6fd84f406cf2a5)
Signed-off-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
---
 drivers/staging/android/logger.c |  2 +-
 drivers/usb/gadget/inode.c       |  6 +--
 fs/aio.c                         | 92 +++++++-------------------------
 fs/block_dev.c                   |  2 +-
 fs/nfs/direct.c                  |  1 -
 fs/ocfs2/file.c                  |  6 +--
 fs/read_write.c                  |  3 --
 fs/udf/file.c                    |  2 +-
 include/linux/aio.h              |  2 -
 mm/page_io.c                     |  1 -
 net/socket.c                     |  2 +-
 11 files changed, 28 insertions(+), 91 deletions(-)

Patch hide | download patch | download mbox

diff --git a/drivers/staging/android/logger.c b/drivers/staging/android/logger.c
index 34519ea14b54..16a6c3179625 100644
--- a/drivers/staging/android/logger.c
+++ b/drivers/staging/android/logger.c
@@ -481,7 +481,7 @@  static ssize_t logger_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	header.sec = now.tv_sec;
 	header.nsec = now.tv_nsec;
 	header.euid = current_euid();
-	header.len = min_t(size_t, iocb->ki_left, LOGGER_ENTRY_MAX_PAYLOAD);
+	header.len = min_t(size_t, iocb->ki_nbytes, LOGGER_ENTRY_MAX_PAYLOAD);
 	header.hdr_size = sizeof(struct logger_entry);
 
 	/* null writes succeed, return zero */
diff --git a/drivers/usb/gadget/inode.c b/drivers/usb/gadget/inode.c
index 570c005062ab..09aae3c48d2c 100644
--- a/drivers/usb/gadget/inode.c
+++ b/drivers/usb/gadget/inode.c
@@ -709,11 +709,11 @@  ep_aio_read(struct kiocb *iocb, const struct iovec *iov,
 	if (unlikely(usb_endpoint_dir_in(&epdata->desc)))
 		return -EINVAL;
 
-	buf = kmalloc(iocb->ki_left, GFP_KERNEL);
+	buf = kmalloc(iocb->ki_nbytes, GFP_KERNEL);
 	if (unlikely(!buf))
 		return -ENOMEM;
 
-	return ep_aio_rwtail(iocb, buf, iocb->ki_left, epdata, iov, nr_segs);
+	return ep_aio_rwtail(iocb, buf, iocb->ki_nbytes, epdata, iov, nr_segs);
 }
 
 static ssize_t
@@ -728,7 +728,7 @@  ep_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	if (unlikely(!usb_endpoint_dir_in(&epdata->desc)))
 		return -EINVAL;
 
-	buf = kmalloc(iocb->ki_left, GFP_KERNEL);
+	buf = kmalloc(iocb->ki_nbytes, GFP_KERNEL);
 	if (unlikely(!buf))
 		return -ENOMEM;
 
diff --git a/fs/aio.c b/fs/aio.c
index c7e23a5832aa..f1b27fc5defb 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -879,7 +879,7 @@  static inline struct kiocb *aio_get_req(struct kioctx *ctx)
 	if (unlikely(!req))
 		goto out_put;
 
-	atomic_set(&req->ki_users, 2);
+	atomic_set(&req->ki_users, 1);
 	req->ki_ctx = ctx;
 
 	return req;
@@ -1279,75 +1279,9 @@  SYSCALL_DEFINE1(io_destroy, aio_context_t, ctx)
 	return -EINVAL;
 }
 
-static void aio_advance_iovec(struct kiocb *iocb, ssize_t ret)
-{
-	struct iovec *iov = &iocb->ki_iovec[iocb->ki_cur_seg];
-
-	BUG_ON(ret <= 0);
-
-	while (iocb->ki_cur_seg < iocb->ki_nr_segs && ret > 0) {
-		ssize_t this = min((ssize_t)iov->iov_len, ret);
-		iov->iov_base += this;
-		iov->iov_len -= this;
-		iocb->ki_left -= this;
-		ret -= this;
-		if (iov->iov_len == 0) {
-			iocb->ki_cur_seg++;
-			iov++;
-		}
-	}
-
-	/* the caller should not have done more io than what fit in
-	 * the remaining iovecs */
-	BUG_ON(ret > 0 && iocb->ki_left == 0);
-}
-
 typedef ssize_t (aio_rw_op)(struct kiocb *, const struct iovec *,
 			    unsigned long, loff_t);
 
-static ssize_t aio_rw_vect_retry(struct kiocb *iocb, int rw, aio_rw_op *rw_op)
-{
-	struct file *file = iocb->ki_filp;
-	struct address_space *mapping = file->f_mapping;
-	struct inode *inode = mapping->host;
-	ssize_t ret = 0;
-
-	/* This matches the pread()/pwrite() logic */
-	if (iocb->ki_pos < 0)
-		return -EINVAL;
-
-	if (rw == WRITE)
-		file_start_write(file);
-	do {
-		ret = rw_op(iocb, &iocb->ki_iovec[iocb->ki_cur_seg],
-			    iocb->ki_nr_segs - iocb->ki_cur_seg,
-			    iocb->ki_pos);
-		if (ret > 0)
-			aio_advance_iovec(iocb, ret);
-
-	/* retry all partial writes.  retry partial reads as long as its a
-	 * regular file. */
-	} while (ret > 0 && iocb->ki_left > 0 &&
-		 (rw == WRITE ||
-		  (!S_ISFIFO(inode->i_mode) && !S_ISSOCK(inode->i_mode))));
-	if (rw == WRITE)
-		file_end_write(file);
-
-	/* This means we must have transferred all that we could */
-	/* No need to retry anymore */
-	if ((ret == 0) || (iocb->ki_left == 0))
-		ret = iocb->ki_nbytes - iocb->ki_left;
-
-	/* If we managed to write some out we return that, rather than
-	 * the eventual error. */
-	if (rw == WRITE
-	    && ret < 0 && ret != -EIOCBQUEUED
-	    && iocb->ki_nbytes - iocb->ki_left)
-		ret = iocb->ki_nbytes - iocb->ki_left;
-
-	return ret;
-}
-
 static ssize_t aio_setup_vectored_rw(int rw, struct kiocb *kiocb, bool compat)
 {
 	ssize_t ret;
@@ -1482,9 +1416,22 @@  rw_common:
 			return ret;
 
 		req->ki_nbytes = ret;
-		req->ki_left = ret;
 
-		ret = aio_rw_vect_retry(req, rw, rw_op);
+		/* XXX: move/kill - rw_verify_area()? */
+		/* This matches the pread()/pwrite() logic */
+		if (req->ki_pos < 0) {
+			ret = -EINVAL;
+			break;
+		}
+
+		if (rw == WRITE)
+			file_start_write(file);
+
+		ret = rw_op(req, req->ki_iovec,
+			    req->ki_nr_segs, req->ki_pos);
+
+		if (rw == WRITE)
+			file_end_write(file);
 		break;
 
 	case IOCB_CMD_READ_ITER:
@@ -1574,7 +1521,6 @@  void aio_kernel_init_iter(struct kiocb *iocb, struct file *filp,
 	iocb->ki_opcode = op;
 	iocb->ki_pos = off;
 	iocb->ki_nbytes = iov_iter_count(iter);
-	iocb->ki_left = iocb->ki_nbytes;
 }
 EXPORT_SYMBOL_GPL(aio_kernel_init_iter);
 
@@ -1673,19 +1619,17 @@  static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
 	req->ki_pos = iocb->aio_offset;
 
 	req->ki_buf = (char __user *)(unsigned long)iocb->aio_buf;
-	req->ki_left = req->ki_nbytes = iocb->aio_nbytes;
+	req->ki_nbytes = iocb->aio_nbytes;
 	req->ki_opcode = iocb->aio_lio_opcode;
 
 	ret = aio_run_iocb(req, compat);
 	if (ret)
 		goto out_put_req;
 
-	aio_put_req(req);	/* drop extra ref to req */
 	return 0;
 out_put_req:
 	atomic_dec(&ctx->reqs_active);
-	aio_put_req(req);	/* drop extra ref to req */
-	aio_put_req(req);	/* drop i/o ref to req */
+	aio_put_req(req);
 	return ret;
 }
 
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 938ec89d197c..85e2a0e19f29 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1674,7 +1674,7 @@  ssize_t blkdev_aio_read(struct kiocb *iocb, const struct iovec *iov,
 		return 0;
 
 	size -= pos;
-	if (size < iocb->ki_left)
+	if (size < iocb->ki_nbytes)
 		nr_segs = iov_shorten((struct iovec *)iov, nr_segs, size);
 	return generic_file_aio_read(iocb, iov, nr_segs, pos);
 }
diff --git a/fs/nfs/direct.c b/fs/nfs/direct.c
index 376a89255029..e90c304f1f5d 100644
--- a/fs/nfs/direct.c
+++ b/fs/nfs/direct.c
@@ -269,7 +269,6 @@  ssize_t nfs_direct_IO(int rw, struct kiocb *iocb, struct iov_iter *iter, loff_t
 	if (!IS_SWAPFILE(inode))
 		return 0;
 
-	VM_BUG_ON(iocb->ki_left != PAGE_SIZE);
 	VM_BUG_ON(iocb->ki_nbytes != PAGE_SIZE);
 
 	if (rw == READ || rw == KERNEL_READ)
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index dfa86a02e160..d72173f09ae6 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -2246,7 +2246,7 @@  static ssize_t ocfs2_file_aio_write(struct kiocb *iocb,
 		file->f_path.dentry->d_name.name,
 		(unsigned int)nr_segs);
 
-	if (iocb->ki_left == 0)
+	if (iocb->ki_nbytes == 0)
 		return 0;
 
 	appending = file->f_flags & O_APPEND ? 1 : 0;
@@ -2297,7 +2297,7 @@  relock:
 
 	can_do_direct = direct_io;
 	ret = ocfs2_prepare_inode_for_write(file, ppos,
-					    iocb->ki_left, appending,
+					    iocb->ki_nbytes, appending,
 					    &can_do_direct, &has_refcount);
 	if (ret < 0) {
 		mlog_errno(ret);
@@ -2305,7 +2305,7 @@  relock:
 	}
 
 	if (direct_io && !is_sync_kiocb(iocb))
-		unaligned_dio = ocfs2_is_io_unaligned(inode, iocb->ki_left,
+		unaligned_dio = ocfs2_is_io_unaligned(inode, iocb->ki_nbytes,
 						      *ppos);
 
 	/*
diff --git a/fs/read_write.c b/fs/read_write.c
index 2ee36621241b..fbcb6e41598e 100644
--- a/fs/read_write.c
+++ b/fs/read_write.c
@@ -437,7 +437,6 @@  ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *pp
 
 	init_sync_kiocb(&kiocb, filp);
 	kiocb.ki_pos = *ppos;
-	kiocb.ki_left = len;
 	kiocb.ki_nbytes = len;
 
 	ret = filp->f_op->aio_read(&kiocb, &iov, 1, kiocb.ki_pos);
@@ -487,7 +486,6 @@  ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, lof
 
 	init_sync_kiocb(&kiocb, filp);
 	kiocb.ki_pos = *ppos;
-	kiocb.ki_left = len;
 	kiocb.ki_nbytes = len;
 
 	ret = filp->f_op->aio_write(&kiocb, &iov, 1, kiocb.ki_pos);
@@ -669,7 +667,6 @@  static ssize_t do_sync_readv_writev(struct file *filp, const struct iovec *iov,
 
 	init_sync_kiocb(&kiocb, filp);
 	kiocb.ki_pos = *ppos;
-	kiocb.ki_left = len;
 	kiocb.ki_nbytes = len;
 
 	ret = fn(&kiocb, iov, nr_segs, kiocb.ki_pos);
diff --git a/fs/udf/file.c b/fs/udf/file.c
index 85bc0000dc91..6df5ef334f9b 100644
--- a/fs/udf/file.c
+++ b/fs/udf/file.c
@@ -141,7 +141,7 @@  static ssize_t udf_file_aio_write(struct kiocb *iocb, const struct iovec *iov,
 	struct file *file = iocb->ki_filp;
 	struct inode *inode = file_inode(file);
 	int err, pos;
-	size_t count = iocb->ki_left;
+	size_t count = iocb->ki_nbytes;
 	struct udf_inode_info *iinfo = UDF_I(inode);
 
 	down_write(&iinfo->i_data_sem);
diff --git a/include/linux/aio.h b/include/linux/aio.h
index 238cb705b19d..45ce7483347f 100644
--- a/include/linux/aio.h
+++ b/include/linux/aio.h
@@ -61,11 +61,9 @@  struct kiocb {
 	unsigned short		ki_opcode;
 	size_t			ki_nbytes; 	/* copy of iocb->aio_nbytes */
 	char 			__user *ki_buf;	/* remaining iocb->aio_buf */
-	size_t			ki_left; 	/* remaining bytes */
 	struct iovec		ki_inline_vec;	/* inline vector */
  	struct iovec		*ki_iovec;
  	unsigned long		ki_nr_segs;
- 	unsigned long		ki_cur_seg;
 
 	struct list_head	ki_list;	/* the aio core uses this
 						 * for cancellation */
diff --git a/mm/page_io.c b/mm/page_io.c
index 8611924c59c0..765f4b7c09d6 100644
--- a/mm/page_io.c
+++ b/mm/page_io.c
@@ -229,7 +229,6 @@  int __swap_writepage(struct page *page, struct writeback_control *wbc,
 
 		init_sync_kiocb(&kiocb, swap_file);
 		kiocb.ki_pos = page_file_offset(page);
-		kiocb.ki_left = PAGE_SIZE;
 		kiocb.ki_nbytes = PAGE_SIZE;
 		iov_iter_init(&iter, &iov, 1, PAGE_SIZE, 0);
 
diff --git a/net/socket.c b/net/socket.c
index a60a04faa6a7..22acff9d617c 100644
--- a/net/socket.c
+++ b/net/socket.c
@@ -972,7 +972,7 @@  static ssize_t sock_aio_read(struct kiocb *iocb, const struct iovec *iov,
 	if (pos != 0)
 		return -ESPIPE;
 
-	if (iocb->ki_left == 0)	/* Match SYS5 behaviour */
+	if (iocb->ki_nbytes == 0)	/* Match SYS5 behaviour */
 		return 0;