From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Tue, 9 Aug 2022 03:04:35 +0000 (-0700)
Subject: Merge tag 'pull-work.iov_iter-rebased' of git://git.kernel.org/pub/scm/linux/kernel... 
X-Git-Tag: v6.1-rc5~645
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=f30adc0d332fdfe5315cb98bd6a7ff0d5cf2aa38;p=platform%2Fkernel%2Flinux-starfive.git

Merge tag 'pull-work.iov_iter-rebased' of git://git./linux/kernel/git/viro/vfs

Pull more iov_iter updates from Al Viro:

 - more new_sync_{read,write}() speedups - ITER_UBUF introduction

 - ITER_PIPE cleanups

 - unification of iov_iter_get_pages/iov_iter_get_pages_alloc and
   switching them to advancing semantics

 - making ITER_PIPE take high-order pages without splitting them

 - handling copy_page_from_iter() for high-order pages properly

* tag 'pull-work.iov_iter-rebased' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (32 commits)
  fix copy_page_from_iter() for compound destinations
  hugetlbfs: copy_page_to_iter() can deal with compound pages
  copy_page_to_iter(): don't split high-order page in case of ITER_PIPE
  expand those iov_iter_advance()...
  pipe_get_pages(): switch to append_pipe()
  get rid of non-advancing variants
  ceph: switch the last caller of iov_iter_get_pages_alloc()
  9p: convert to advancing variant of iov_iter_get_pages_alloc()
  af_alg_make_sg(): switch to advancing variant of iov_iter_get_pages()
  iter_to_pipe(): switch to advancing variant of iov_iter_get_pages()
  block: convert to advancing variants of iov_iter_get_pages{,_alloc}()
  iov_iter: advancing variants of iov_iter_get_pages{,_alloc}()
  iov_iter: saner helper for page array allocation
  fold __pipe_get_pages() into pipe_get_pages()
  ITER_XARRAY: don't open-code DIV_ROUND_UP()
  unify the rest of iov_iter_get_pages()/iov_iter_get_pages_alloc() guts
  unify xarray_get_pages() and xarray_get_pages_alloc()
  unify pipe_get_pages() and pipe_get_pages_alloc()
  iov_iter_get_pages(): sanity-check arguments
  iov_iter_get_pages_alloc(): lift freeing pages array on failure exits into wrapper
  ...
---

f30adc0d332fdfe5315cb98bd6a7ff0d5cf2aa38
diff --cc fs/hugetlbfs/inode.c
index fe0e374,40e124a..f7a5b51
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@@ -282,38 -284,10 +282,9 @@@ hugetlb_get_unmapped_area(struct file *
  }
  #endif
  
- static size_t
- hugetlbfs_read_actor(struct page *page, unsigned long offset,
- 			struct iov_iter *to, unsigned long size)
- {
- 	size_t copied = 0;
- 	int i, chunksize;
- 
- 	/* Find which 4k chunk and offset with in that chunk */
- 	i = offset >> PAGE_SHIFT;
- 	offset = offset & ~PAGE_MASK;
- 
- 	while (size) {
- 		size_t n;
- 		chunksize = PAGE_SIZE;
- 		if (offset)
- 			chunksize -= offset;
- 		if (chunksize > size)
- 			chunksize = size;
- 		n = copy_page_to_iter(&page[i], offset, chunksize, to);
- 		copied += n;
- 		if (n != chunksize)
- 			return copied;
- 		offset = 0;
- 		size -= chunksize;
- 		i++;
- 	}
- 	return copied;
- }
- 
  /*
   * Support for read() - Find the page attached to f_mapping and copy out the
 - * data. Its *very* similar to generic_file_buffered_read(), we can't use that
 - * since it has PAGE_SIZE assumptions.
 + * data. This provides functionality similar to filemap_read().
   */
  static ssize_t hugetlbfs_read_iter(struct kiocb *iocb, struct iov_iter *to)
  {
diff --cc net/9p/client.c
index 5bf4dfe,cb43242..0a6110e
--- a/net/9p/client.c
+++ b/net/9p/client.c
@@@ -1528,32 -1526,34 +1530,34 @@@ p9_client_read_once(struct p9_fid *fid
  	}
  
  	*err = p9pdu_readf(&req->rc, clnt->proto_version,
- 			   "D", &count, &dataptr);
+ 			   "D", &received, &dataptr);
  	if (*err) {
+ 		if (!non_zc)
+ 			iov_iter_revert(to, count - iov_iter_count(to));
  		trace_9p_protocol_dump(clnt, &req->rc);
 -		p9_tag_remove(clnt, req);
 +		p9_req_put(clnt, req);
  		return 0;
  	}
- 	if (rsize < count) {
- 		pr_err("bogus RREAD count (%d > %d)\n", count, rsize);
- 		count = rsize;
+ 	if (rsize < received) {
+ 		pr_err("bogus RREAD count (%d > %d)\n", received, rsize);
+ 		received = rsize;
  	}
  
  	p9_debug(P9_DEBUG_9P, "<<< RREAD count %d\n", count);
  
  	if (non_zc) {
- 		int n = copy_to_iter(dataptr, count, to);
+ 		int n = copy_to_iter(dataptr, received, to);
  
- 		if (n != count) {
+ 		if (n != received) {
  			*err = -EFAULT;
 -			p9_tag_remove(clnt, req);
 +			p9_req_put(clnt, req);
  			return n;
  		}
  	} else {
- 		iov_iter_advance(to, count);
+ 		iov_iter_revert(to, count - received - iov_iter_count(to));
  	}
 -	p9_tag_remove(clnt, req);
 +	p9_req_put(clnt, req);
- 	return count;
+ 	return received;
  }
  EXPORT_SYMBOL(p9_client_read_once);
  
@@@ -1592,23 -1594,24 +1598,24 @@@ p9_client_write(struct p9_fid *fid, u6
  			break;
  		}
  
- 		*err = p9pdu_readf(&req->rc, clnt->proto_version, "d", &count);
+ 		*err = p9pdu_readf(&req->rc, clnt->proto_version, "d", &written);
  		if (*err) {
+ 			iov_iter_revert(from, count - iov_iter_count(from));
  			trace_9p_protocol_dump(clnt, &req->rc);
 -			p9_tag_remove(clnt, req);
 +			p9_req_put(clnt, req);
  			break;
  		}
- 		if (rsize < count) {
- 			pr_err("bogus RWRITE count (%d > %d)\n", count, rsize);
- 			count = rsize;
+ 		if (rsize < written) {
+ 			pr_err("bogus RWRITE count (%d > %d)\n", written, rsize);
+ 			written = rsize;
  		}
  
  		p9_debug(P9_DEBUG_9P, "<<< RWRITE count %d\n", count);
  
 -		p9_tag_remove(clnt, req);
 +		p9_req_put(clnt, req);
- 		iov_iter_advance(from, count);
- 		total += count;
- 		offset += count;
+ 		iov_iter_revert(from, count - written - iov_iter_count(from));
+ 		total += written;
+ 		offset += written;
  	}
  	return total;
  }