The patch titled
fuse: update file size on short read
has been added to the -mm tree. Its filename is
fuse-update-file-size-on-short-read.patch
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: fuse: update file size on short read
From: Miklos Szeredi <mszeredi@xxxxxxx>
If the READ request returned a short count, then either
- cached size is incorrect
- filesystem is buggy, as short reads are only allowed on EOF
So assume that the size is wrong and refresh it, so that cached read() doesn't
zero fill the missing chunk.
Signed-off-by: Miklos Szeredi <mszeredi@xxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/fuse/file.c | 42 ++++++++++++++++++++++++++++++++++++++----
1 file changed, 38 insertions(+), 4 deletions(-)
diff -puN fs/fuse/file.c~fuse-update-file-size-on-short-read fs/fuse/file.c
--- a/fs/fuse/file.c~fuse-update-file-size-on-short-read
+++ a/fs/fuse/file.c
@@ -398,11 +398,26 @@ static size_t fuse_send_read(struct fuse
return req->out.args[0].size;
}
+static void fuse_read_update_size(struct inode *inode, loff_t size)
+{
+ struct fuse_conn *fc = get_fuse_conn(inode);
+ struct fuse_inode *fi = get_fuse_inode(inode);
+
+ spin_lock(&fc->lock);
+ fi->attr_version = ++fc->attr_version;
+ if (size < inode->i_size)
+ i_size_write(inode, size);
+ spin_unlock(&fc->lock);
+}
+
static int fuse_readpage(struct file *file, struct page *page)
{
struct inode *inode = page->mapping->host;
struct fuse_conn *fc = get_fuse_conn(inode);
struct fuse_req *req;
+ size_t num_read;
+ loff_t pos = page_offset(page);
+ size_t count = PAGE_CACHE_SIZE;
int err;
err = -EIO;
@@ -424,12 +439,20 @@ static int fuse_readpage(struct file *fi
req->out.page_zeroing = 1;
req->num_pages = 1;
req->pages[0] = page;
- fuse_send_read(req, file, inode, page_offset(page), PAGE_CACHE_SIZE,
- NULL);
+ num_read = fuse_send_read(req, file, inode, pos, count, NULL);
err = req->out.h.error;
fuse_put_request(fc, req);
- if (!err)
+
+ if (!err) {
+ /*
+ * Short read means EOF. If file size is larger, truncate it
+ */
+ if (num_read < count)
+ fuse_read_update_size(inode, pos + num_read);
+
SetPageUptodate(page);
+ }
+
fuse_invalidate_attr(inode); /* atime changed */
out:
unlock_page(page);
@@ -439,8 +462,19 @@ static int fuse_readpage(struct file *fi
static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req)
{
int i;
+ size_t count = req->misc.read_in.size;
+ size_t num_read = req->out.args[0].size;
+ struct inode *inode = req->pages[0]->mapping->host;
- fuse_invalidate_attr(req->pages[0]->mapping->host); /* atime changed */
+ /*
+ * Short read means EOF. If file size is larger, truncate it
+ */
+ if (!req->out.h.error && num_read < count) {
+ loff_t pos = page_offset(req->pages[0]) + num_read;
+ fuse_read_update_size(inode, pos);
+ }
+
+ fuse_invalidate_attr(inode); /* atime changed */
for (i = 0; i < req->num_pages; i++) {
struct page *page = req->pages[i];
_
Patches currently in -mm which might be from mszeredi@xxxxxxx are
mm-rotate_reclaimable_page-cleanup.patch
vfs-create-proc-pid-mountinfo.patch
vfs-mountinfo-mm-fix.patch
vfs-pnode-cleanup.patch
vfs-mountinfo-stable-peer-group-id.patch
vfs-mountinfo-show-dominating-group-id.patch
vfs-optimization-to-proc-pid-mountinfo-patch.patch
vfs-mountinfo-only-show-mounts-under-tasks-root.patch
vfs-remove-lives_below_in_same_fs.patch
mm-bdi-export-bdi-attributes-in-sysfs.patch
mm-bdi-export-bdi-attributes-in-sysfs-fix.patch
mm-bdi-export-bdi-attributes-in-sysfs-fix-2.patch
mm-bdi-export-bdi-attributes-in-sysfs-fix-3.patch
mm-bdi-export-bdi-attributes-in-sysfs-fix-4.patch
mm-bdi-export-bdi-attributes-in-sysfs-ia64-fix.patch
mm-bdi-expose-the-bdi-object-in-sysfs-for-nfs.patch
mm-bdi-expose-the-bdi-object-in-sysfs-for-nfs-fix.patch
mm-bdi-expose-the-bdi-object-in-sysfs-for-fuse.patch
mm-bdi-expose-the-bdi-object-in-sysfs-for-fuse-fix.patch
mm-bdi-allow-setting-a-minimum-for-the-bdi-dirty-limit.patch
mm-bdi-allow-setting-a-maximum-for-the-bdi-dirty-limit.patch
mm-bdi-allow-setting-a-maximum-for-the-bdi-dirty-limit-fix.patch
mm-bdi-move-statistics-to-debugfs.patch
mm-bdi-export-bdi_writeout_inc.patch
mm-add-nr_writeback_temp-counter.patch
mm-allow-not-updating-bdi-stats-in-end_page_writeback.patch
fuse-support-writable-mmap.patch
fuse-clean-up-setting-i_size-in-write.patch
fuse-implement-perform_write.patch
fuse-update-file-size-on-short-read.patch
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