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From: David Howells <dhowells@redhat.com>
To: viro@zeniv.linux.org.uk
Cc: dhowells@redhat.com, linux-afs@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: [PATCH 12/25] afs: Don't invoke the server to read data beyond EOF [ver #2]
Date: Wed, 24 Oct 2018 00:59:14 +0100	[thread overview]
Message-ID: <154033915412.12041.8363518299700412202.stgit@warthog.procyon.org.uk> (raw)
In-Reply-To: <154033906284.12041.12908874734066278152.stgit@warthog.procyon.org.uk>

When writing a new page, clear space in the page rather than attempting to
load it from the server if the space is beyond the EOF.

Signed-off-by: David Howells <dhowells@redhat.com>
---

 fs/afs/write.c |   11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/fs/afs/write.c b/fs/afs/write.c
index fdb9d6024126..11066a3248ba 100644
--- a/fs/afs/write.c
+++ b/fs/afs/write.c
@@ -33,10 +33,21 @@ static int afs_fill_page(struct afs_vnode *vnode, struct key *key,
 			 loff_t pos, unsigned int len, struct page *page)
 {
 	struct afs_read *req;
+	size_t p;
+	void *data;
 	int ret;
 
 	_enter(",,%llu", (unsigned long long)pos);
 
+	if (pos >= vnode->vfs_inode.i_size) {
+		p = pos & ~PAGE_MASK;
+		ASSERTCMP(p + len, <=, PAGE_SIZE);
+		data = kmap(page);
+		memset(data + p, 0, len);
+		kunmap(page);
+		return 0;
+	}
+
 	req = kzalloc(sizeof(struct afs_read) + sizeof(struct page *),
 		      GFP_KERNEL);
 	if (!req)


  parent reply	other threads:[~2018-10-24  3:38 UTC|newest]

Thread overview: 28+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-10-23 23:57 [PATCH 00/25] AFS development [ver #2] David Howells
2018-10-23 23:57 ` [PATCH 01/25] amd-gpu: Don't undefine READ and WRITE " David Howells
2018-11-01 22:06   ` Pavel Machek
2018-10-23 23:57 ` [PATCH 02/25] iov_iter: Use accessor function " David Howells
2018-11-28  1:39   ` NeilBrown
2018-10-23 23:58 ` [PATCH 03/25] iov_iter: Separate type from direction and use accessor functions " David Howells
2018-10-23 23:58 ` [PATCH 04/25] iov_iter: Add I/O discard iterator " David Howells
2018-10-23 23:58 ` [PATCH 05/25] afs: Better tracing of protocol errors " David Howells
2018-10-23 23:58 ` [PATCH 06/25] afs: Set up the iov_iter before calling afs_extract_data() " David Howells
2018-10-23 23:58 ` [PATCH 07/25] afs: Improve FS server rotation error handling " David Howells
2018-10-23 23:58 ` [PATCH 08/25] afs: Implement VL server rotation " David Howells
2018-10-23 23:58 ` [PATCH 09/25] afs: Fix TTL on VL server and address lists " David Howells
2018-10-23 23:59 ` [PATCH 10/25] afs: Handle EIO from delivery function " David Howells
2018-10-23 23:59 ` [PATCH 11/25] afs: Add a couple of tracepoints to log I/O errors " David Howells
2018-10-23 23:59 ` David Howells [this message]
2018-10-23 23:59 ` [PATCH 13/25] afs: Increase to 64-bit volume ID and 96-bit vnode ID for YFS " David Howells
2018-10-23 23:59 ` [PATCH 14/25] afs: Commit the status on a new file/dir/symlink " David Howells
2018-10-23 23:59 ` [PATCH 15/25] afs: Remove callback details from afs_callback_break struct " David Howells
2018-10-23 23:59 ` [PATCH 16/25] afs: Implement the YFS cache manager service " David Howells
2018-10-23 23:59 ` [PATCH 17/25] afs: Fix FS.FetchStatus delivery from updating wrong vnode " David Howells
2018-10-23 23:59 ` [PATCH 18/25] afs: Calc callback expiry in op reply delivery " David Howells
2018-10-24  0:00 ` [PATCH 19/25] afs: Get the target vnode in afs_rmdir() and get a callback on it " David Howells
2018-10-24  0:00 ` [PATCH 20/25] afs: Expand data structure fields to support YFS " David Howells
2018-10-24  0:00 ` [PATCH 21/25] afs: Implement YFS support in the fs client " David Howells
2018-10-24  0:00 ` [PATCH 22/25] afs: Allow dumping of server cursor on operation failure " David Howells
2018-10-24  0:00 ` [PATCH 23/25] afs: Eliminate the address pointer from the address list cursor " David Howells
2018-10-24  0:00 ` [PATCH 24/25] afs: Fix callback handling " David Howells
2018-10-24  0:00 ` [PATCH 25/25] afs: Probe multiple fileservers simultaneously " David Howells

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