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-rw-r--r--fs/cifs/file.c241
1 files changed, 99 insertions, 142 deletions
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index c672afe..00b926c 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -1092,58 +1092,20 @@ static int cifs_partialpagewrite(struct page *page, unsigned from, unsigned to)
static int cifs_writepages(struct address_space *mapping,
struct writeback_control *wbc)
{
- unsigned int bytes_to_write;
- unsigned int bytes_written;
- struct cifs_sb_info *cifs_sb;
- int done = 0;
- pgoff_t end;
- pgoff_t index;
- int range_whole = 0;
- struct kvec *iov;
- int len;
- int n_iov = 0;
- pgoff_t next;
- int nr_pages;
- __u64 offset = 0;
- struct cifsFileInfo *open_file;
- struct cifsTconInfo *tcon;
- struct cifsInodeInfo *cifsi = CIFS_I(mapping->host);
+ struct cifs_sb_info *cifs_sb = CIFS_SB(mapping->host->i_sb);
+ bool done = false, scanned = false, range_whole = false;
+ pgoff_t end, index;
+ struct cifs_writedata *wdata;
struct page *page;
- struct pagevec pvec;
int rc = 0;
- int scanned = 0;
- int xid;
-
- cifs_sb = CIFS_SB(mapping->host->i_sb);
/*
- * If wsize is smaller that the page cache size, default to writing
+ * If wsize is smaller than the page cache size, default to writing
* one page at a time via cifs_writepage
*/
if (cifs_sb->wsize < PAGE_CACHE_SIZE)
return generic_writepages(mapping, wbc);
- iov = kmalloc(32 * sizeof(struct kvec), GFP_KERNEL);
- if (iov == NULL)
- return generic_writepages(mapping, wbc);
-
- /*
- * if there's no open file, then this is likely to fail too,
- * but it'll at least handle the return. Maybe it should be
- * a BUG() instead?
- */
- open_file = find_writable_file(CIFS_I(mapping->host), false);
- if (!open_file) {
- kfree(iov);
- return generic_writepages(mapping, wbc);
- }
-
- tcon = tlink_tcon(open_file->tlink);
- cifsFileInfo_put(open_file);
-
- xid = GetXid();
-
- pagevec_init(&pvec, 0);
if (wbc->range_cyclic) {
index = mapping->writeback_index; /* Start from prev offset */
end = -1;
@@ -1151,24 +1113,49 @@ static int cifs_writepages(struct address_space *mapping,
index = wbc->range_start >> PAGE_CACHE_SHIFT;
end = wbc->range_end >> PAGE_CACHE_SHIFT;
if (wbc->range_start == 0 && wbc->range_end == LLONG_MAX)
- range_whole = 1;
- scanned = 1;
+ range_whole = true;
+ scanned = true;
}
retry:
- while (!done && (index <= end) &&
- (nr_pages = pagevec_lookup_tag(&pvec, mapping, &index,
- PAGECACHE_TAG_DIRTY,
- min(end - index, (pgoff_t)PAGEVEC_SIZE - 1) + 1))) {
- int first;
- unsigned int i;
-
- first = -1;
- next = 0;
- n_iov = 0;
- bytes_to_write = 0;
-
- for (i = 0; i < nr_pages; i++) {
- page = pvec.pages[i];
+ while (!done && index <= end) {
+ unsigned int i, nr_pages, found_pages;
+ pgoff_t next = 0, tofind;
+ struct page **pages;
+
+ tofind = min((cifs_sb->wsize / PAGE_CACHE_SIZE) - 1,
+ end - index) + 1;
+
+ wdata = cifs_writedata_alloc((unsigned int)tofind);
+ if (!wdata) {
+ rc = -ENOMEM;
+ break;
+ }
+
+ /*
+ * find_get_pages_tag seems to return a max of 256 on each
+ * iteration, so we must call it several times in order to
+ * fill the array or the wsize is effectively limited to
+ * 256 * PAGE_CACHE_SIZE.
+ */
+ found_pages = 0;
+ pages = wdata->pages;
+ do {
+ nr_pages = find_get_pages_tag(mapping, &index,
+ PAGECACHE_TAG_DIRTY,
+ tofind, pages);
+ found_pages += nr_pages;
+ tofind -= nr_pages;
+ pages += nr_pages;
+ } while (nr_pages && tofind && index <= end);
+
+ if (found_pages == 0) {
+ kref_put(&wdata->refcount, cifs_writedata_release);
+ break;
+ }
+
+ nr_pages = 0;
+ for (i = 0; i < found_pages; i++) {
+ page = wdata->pages[i];
/*
* At this point we hold neither mapping->tree_lock nor
* lock on the page itself: the page may be truncated or
@@ -1177,7 +1164,7 @@ retry:
* mapping
*/
- if (first < 0)
+ if (nr_pages == 0)
lock_page(page);
else if (!trylock_page(page))
break;
@@ -1188,7 +1175,7 @@ retry:
}
if (!wbc->range_cyclic && page->index > end) {
- done = 1;
+ done = true;
unlock_page(page);
break;
}
@@ -1215,119 +1202,89 @@ retry:
set_page_writeback(page);
if (page_offset(page) >= mapping->host->i_size) {
- done = 1;
+ done = true;
unlock_page(page);
end_page_writeback(page);
break;
}
- /*
- * BB can we get rid of this? pages are held by pvec
- */
- page_cache_get(page);
+ wdata->pages[i] = page;
+ next = page->index + 1;
+ ++nr_pages;
+ }
- len = min(mapping->host->i_size - page_offset(page),
- (loff_t)PAGE_CACHE_SIZE);
+ /* reset index to refind any pages skipped */
+ if (nr_pages == 0)
+ index = wdata->pages[0]->index + 1;
- /* reserve iov[0] for the smb header */
- n_iov++;
- iov[n_iov].iov_base = kmap(page);
- iov[n_iov].iov_len = len;
- bytes_to_write += len;
+ /* put any pages we aren't going to use */
+ for (i = nr_pages; i < found_pages; i++) {
+ page_cache_release(wdata->pages[i]);
+ wdata->pages[i] = NULL;
+ }
- if (first < 0) {
- first = i;
- offset = page_offset(page);
- }
- next = page->index + 1;
- if (bytes_to_write + PAGE_CACHE_SIZE > cifs_sb->wsize)
- break;
+ /* nothing to write? */
+ if (nr_pages == 0) {
+ kref_put(&wdata->refcount, cifs_writedata_release);
+ continue;
}
- if (n_iov) {
-retry_write:
- open_file = find_writable_file(CIFS_I(mapping->host),
- false);
- if (!open_file) {
- cERROR(1, "No writable handles for inode");
- rc = -EBADF;
- } else {
- rc = CIFSSMBWrite2(xid, tcon, open_file->netfid,
- bytes_to_write, offset,
- &bytes_written, iov, n_iov,
- 0);
- cifsFileInfo_put(open_file);
- }
- cFYI(1, "Write2 rc=%d, wrote=%u", rc, bytes_written);
+ wdata->sync_mode = wbc->sync_mode;
+ wdata->nr_pages = nr_pages;
+ wdata->offset = page_offset(wdata->pages[0]);
- /*
- * For now, treat a short write as if nothing got
- * written. A zero length write however indicates
- * ENOSPC or EFBIG. We have no way to know which
- * though, so call it ENOSPC for now. EFBIG would
- * get translated to AS_EIO anyway.
- *
- * FIXME: make it take into account the data that did
- * get written
- */
- if (rc == 0) {
- if (bytes_written == 0)
- rc = -ENOSPC;
- else if (bytes_written < bytes_to_write)
- rc = -EAGAIN;
+ do {
+ if (wdata->cfile != NULL)
+ cifsFileInfo_put(wdata->cfile);
+ wdata->cfile = find_writable_file(CIFS_I(mapping->host),
+ false);
+ if (!wdata->cfile) {
+ cERROR(1, "No writable handles for inode");
+ rc = -EBADF;
+ break;
}
+ rc = cifs_async_writev(wdata);
+ } while (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN);
- /* retry on data-integrity flush */
- if (wbc->sync_mode == WB_SYNC_ALL && rc == -EAGAIN)
- goto retry_write;
+ for (i = 0; i < nr_pages; ++i)
+ unlock_page(wdata->pages[i]);
- /* fix the stats and EOF */
- if (bytes_written > 0) {
- cifs_stats_bytes_written(tcon, bytes_written);
- cifs_update_eof(cifsi, offset, bytes_written);
- }
-
- for (i = 0; i < n_iov; i++) {
- page = pvec.pages[first + i];
- /* on retryable write error, redirty page */
+ /* send failure -- clean up the mess */
+ if (rc != 0) {
+ for (i = 0; i < nr_pages; ++i) {
if (rc == -EAGAIN)
- redirty_page_for_writepage(wbc, page);
- else if (rc != 0)
- SetPageError(page);
- kunmap(page);
- unlock_page(page);
- end_page_writeback(page);
- page_cache_release(page);
+ redirty_page_for_writepage(wbc,
+ wdata->pages[i]);
+ else
+ SetPageError(wdata->pages[i]);
+ end_page_writeback(wdata->pages[i]);
+ page_cache_release(wdata->pages[i]);
}
-
if (rc != -EAGAIN)
mapping_set_error(mapping, rc);
- else
- rc = 0;
+ }
+ kref_put(&wdata->refcount, cifs_writedata_release);
- if ((wbc->nr_to_write -= n_iov) <= 0)
- done = 1;
- index = next;
- } else
- /* Need to re-find the pages we skipped */
- index = pvec.pages[0]->index + 1;
+ wbc->nr_to_write -= nr_pages;
+ if (wbc->nr_to_write <= 0)
+ done = true;
- pagevec_release(&pvec);
+ index = next;
}
+
if (!scanned && !done) {
/*
* We hit the last page and there is more work to be done: wrap
* back to the start of the file
*/
- scanned = 1;
+ scanned = true;
index = 0;
goto retry;
}
+
if (wbc->range_cyclic || (range_whole && wbc->nr_to_write > 0))
mapping->writeback_index = index;
- FreeXid(xid);
- kfree(iov);
return rc;
}
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