* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/fs.h>
+#include <linux/backing-dev.h>
#include <linux/stat.h>
#include <linux/fcntl.h>
+#include <linux/mpage.h>
#include <linux/pagemap.h>
#include <linux/pagevec.h>
#include <linux/smp_lock.h>
+#include <linux/writeback.h>
+#include <linux/delay.h>
#include <asm/div64.h>
#include "cifsfs.h"
#include "cifspdu.h"
private_data->pInode = inode;
private_data->invalidHandle = FALSE;
private_data->closePend = FALSE;
+ /* we have to track num writers to the inode, since writepages
+ does not tell us which handle the write is for so there can
+ be a close (overlapping with write) of the filehandle that
+ cifs_writepages chose to use */
+ atomic_set(&private_data->wrtPending,0);
return private_data;
}
if (file->f_dentry->d_inode->i_mapping) {
/* BB no need to lock inode until after invalidate
since namei code should already have it locked? */
- filemap_fdatawrite(file->f_dentry->d_inode->i_mapping);
- filemap_fdatawait(file->f_dentry->d_inode->i_mapping);
+ filemap_write_and_wait(file->f_dentry->d_inode->i_mapping);
}
cFYI(1, ("invalidating remote inode since open detected it "
"changed"));
pCifsInode = CIFS_I(inode);
if (pCifsInode) {
if (can_flush) {
- filemap_fdatawrite(inode->i_mapping);
- filemap_fdatawait(inode->i_mapping);
+ filemap_write_and_wait(inode->i_mapping);
/* temporarily disable caching while we
go to server to get inode info */
pCifsInode->clientCanCacheAll = FALSE;
/* no sense reconnecting to close a file that is
already closed */
if (pTcon->tidStatus != CifsNeedReconnect) {
+ int timeout = 2;
+ while((atomic_read(&pSMBFile->wrtPending) != 0)
+ && (timeout < 1000) ) {
+ /* Give write a better chance to get to
+ server ahead of the close. We do not
+ want to add a wait_q here as it would
+ increase the memory utilization as
+ the struct would be in each open file,
+ but this should give enough time to
+ clear the socket */
+ write_unlock(&file->f_owner.lock);
+ cERROR(1,("close with pending writes"));
+ msleep(timeout);
+ write_lock(&file->f_owner.lock);
+ timeout *= 4;
+ }
write_unlock(&file->f_owner.lock);
rc = CIFSSMBClose(xid, pTcon,
pSMBFile->netfid);
struct kvec iov[2];
unsigned int len;
- len = min(cifs_sb->wsize,
+ len = min((size_t)cifs_sb->wsize,
write_size - total_written);
/* iov[0] is reserved for smb header */
iov[1].iov_base = (char *)write_data +
return total_written;
}
-static struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode)
+struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode)
{
struct cifsFileInfo *open_file;
+ int rc;
read_lock(&GlobalSMBSeslock);
list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
if (open_file->pfile &&
((open_file->pfile->f_flags & O_RDWR) ||
(open_file->pfile->f_flags & O_WRONLY))) {
+ atomic_inc(&open_file->wrtPending);
read_unlock(&GlobalSMBSeslock);
+ if((open_file->invalidHandle) &&
+ (!open_file->closePend) /* BB fixme -since the second clause can not be true remove it BB */) {
+ rc = cifs_reopen_file(&cifs_inode->vfs_inode,
+ open_file->pfile, FALSE);
+ /* if it fails, try another handle - might be */
+ /* dangerous to hold up writepages with retry */
+ if(rc) {
+ cFYI(1,("failed on reopen file in wp"));
+ read_lock(&GlobalSMBSeslock);
+ /* can not use this handle, no write
+ pending on this one after all */
+ atomic_dec
+ (&open_file->wrtPending);
+ continue;
+ }
+ }
return open_file;
}
}
if (open_file) {
bytes_written = cifs_write(open_file->pfile, write_data,
to-from, &offset);
+ atomic_dec(&open_file->wrtPending);
/* Does mm or vfs already set times? */
inode->i_atime = inode->i_mtime = current_fs_time(inode->i_sb);
if ((bytes_written > 0) && (offset)) {
return rc;
}
-#if 0
+#ifdef CONFIG_CIFS_EXPERIMENTAL
static int cifs_writepages(struct address_space *mapping,
- struct writeback_control *wbc)
+ struct writeback_control *wbc)
{
- int rc = -EFAULT;
+ struct backing_dev_info *bdi = mapping->backing_dev_info;
+ unsigned int bytes_to_write;
+ unsigned int bytes_written;
+ struct cifs_sb_info *cifs_sb;
+ int done = 0;
+ pgoff_t end = -1;
+ pgoff_t index;
+ int is_range = 0;
+ struct kvec iov[32];
+ int len;
+ int n_iov = 0;
+ pgoff_t next;
+ int nr_pages;
+ __u64 offset = 0;
+ struct cifsFileInfo *open_file;
+ 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
+ * one page at a time via cifs_writepage
+ */
+ if (cifs_sb->wsize < PAGE_CACHE_SIZE)
+ return generic_writepages(mapping, wbc);
+
+ /* BB FIXME we do not have code to sign across multiple buffers yet,
+ so go to older writepage style write which we can sign if needed */
+ if((cifs_sb->tcon->ses) && (cifs_sb->tcon->ses->server))
+ if(cifs_sb->tcon->ses->server->secMode &
+ (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
+ return generic_writepages(mapping, wbc);
+
+ /*
+ * BB: Is this meaningful for a non-block-device file system?
+ * If it is, we should test it again after we do I/O
+ */
+ if (wbc->nonblocking && bdi_write_congested(bdi)) {
+ wbc->encountered_congestion = 1;
+ return 0;
+ }
+
xid = GetXid();
- /* Find contiguous pages then iterate through repeating
- call 16K write then Setpageuptodate or if LARGE_WRITE_X
- support then send larger writes via kevec so as to eliminate
- a memcpy */
+ pagevec_init(&pvec, 0);
+ if (wbc->sync_mode == WB_SYNC_NONE)
+ index = mapping->writeback_index; /* Start from prev offset */
+ else {
+ index = 0;
+ scanned = 1;
+ }
+ if (wbc->start || wbc->end) {
+ index = wbc->start >> PAGE_CACHE_SHIFT;
+ end = wbc->end >> PAGE_CACHE_SHIFT;
+ is_range = 1;
+ scanned = 1;
+ }
+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];
+ /*
+ * At this point we hold neither mapping->tree_lock nor
+ * lock on the page itself: the page may be truncated or
+ * invalidated (changing page->mapping to NULL), or even
+ * swizzled back from swapper_space to tmpfs file
+ * mapping
+ */
+
+ if (first < 0)
+ lock_page(page);
+ else if (TestSetPageLocked(page))
+ break;
+
+ if (unlikely(page->mapping != mapping)) {
+ unlock_page(page);
+ break;
+ }
+
+ if (unlikely(is_range) && (page->index > end)) {
+ done = 1;
+ unlock_page(page);
+ break;
+ }
+
+ if (next && (page->index != next)) {
+ /* Not next consecutive page */
+ unlock_page(page);
+ break;
+ }
+
+ if (wbc->sync_mode != WB_SYNC_NONE)
+ wait_on_page_writeback(page);
+
+ if (PageWriteback(page) ||
+ !test_clear_page_dirty(page)) {
+ unlock_page(page);
+ break;
+ }
+
+ if (page_offset(page) >= mapping->host->i_size) {
+ done = 1;
+ unlock_page(page);
+ break;
+ }
+
+ /*
+ * BB can we get rid of this? pages are held by pvec
+ */
+ page_cache_get(page);
+
+ len = min(mapping->host->i_size - page_offset(page),
+ (loff_t)PAGE_CACHE_SIZE);
+
+ /* 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;
+
+ if (first < 0) {
+ first = i;
+ offset = page_offset(page);
+ }
+ next = page->index + 1;
+ if (bytes_to_write + PAGE_CACHE_SIZE > cifs_sb->wsize)
+ break;
+ }
+ if (n_iov) {
+ /* Search for a writable handle every time we call
+ * CIFSSMBWrite2. We can't rely on the last handle
+ * we used to still be valid
+ */
+ open_file = find_writable_file(CIFS_I(mapping->host));
+ if (!open_file) {
+ cERROR(1, ("No writable handles for inode"));
+ rc = -EBADF;
+ } else {
+ rc = CIFSSMBWrite2(xid, cifs_sb->tcon,
+ open_file->netfid,
+ bytes_to_write, offset,
+ &bytes_written, iov, n_iov,
+ 1);
+ atomic_dec(&open_file->wrtPending);
+ if (rc || bytes_written < bytes_to_write) {
+ cERROR(1,("Write2 ret %d, written = %d",
+ rc, bytes_written));
+ /* BB what if continued retry is
+ requested via mount flags? */
+ set_bit(AS_EIO, &mapping->flags);
+ SetPageError(page);
+ } else {
+ cifs_stats_bytes_written(cifs_sb->tcon,
+ bytes_written);
+ }
+ }
+ for (i = 0; i < n_iov; i++) {
+ page = pvec.pages[first + i];
+ kunmap(page);
+ unlock_page(page);
+ page_cache_release(page);
+ }
+ if ((wbc->nr_to_write -= n_iov) <= 0)
+ done = 1;
+ index = next;
+ }
+ pagevec_release(&pvec);
+ }
+ 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;
+ index = 0;
+ goto retry;
+ }
+ if (!is_range)
+ mapping->writeback_index = index;
+
FreeXid(xid);
+
return rc;
}
#endif
page caching in the current Linux kernel design */
int is_size_safe_to_change(struct cifsInodeInfo *cifsInode)
{
- if (cifsInode && find_writable_file(cifsInode))
+ struct cifsFileInfo *open_file = NULL;
+
+ if (cifsInode)
+ open_file = find_writable_file(cifsInode);
+
+ if(open_file) {
+ /* there is not actually a write pending so let
+ this handle go free and allow it to
+ be closable if needed */
+ atomic_dec(&open_file->wrtPending);
return 0;
- else
+ } else
return 1;
}
.readpage = cifs_readpage,
.readpages = cifs_readpages,
.writepage = cifs_writepage,
+#ifdef CONFIG_CIFS_EXPERIMENTAL
+ .writepages = cifs_writepages,
+#endif
.prepare_write = cifs_prepare_write,
.commit_write = cifs_commit_write,
.set_page_dirty = __set_page_dirty_nobuffers,
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