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-rw-r--r--fs/cifs/file.c130
1 files changed, 68 insertions, 62 deletions
diff --git a/fs/cifs/file.c b/fs/cifs/file.c
index cbefe1f1f9fe..c4a8a0605125 100644
--- a/fs/cifs/file.c
+++ b/fs/cifs/file.c
@@ -107,7 +107,7 @@ static inline int cifs_open_inode_helper(struct inode *inode, struct file *file,
/* want handles we can use to read with first
in the list so we do not have to walk the
- list to search for one in prepare_write */
+ list to search for one in write_begin */
if ((file->f_flags & O_ACCMODE) == O_WRONLY) {
list_add_tail(&pCifsFile->flist,
&pCifsInode->openFileList);
@@ -915,7 +915,7 @@ ssize_t cifs_user_write(struct file *file, const char __user *write_data,
}
static ssize_t cifs_write(struct file *file, const char *write_data,
- size_t write_size, loff_t *poffset)
+ size_t write_size, loff_t *poffset)
{
int rc = 0;
unsigned int bytes_written = 0;
@@ -1065,6 +1065,7 @@ struct cifsFileInfo *find_readable_file(struct cifsInodeInfo *cifs_inode)
struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode)
{
struct cifsFileInfo *open_file;
+ bool any_available = false;
int rc;
/* Having a null inode here (because mapping->host was set to zero by
@@ -1080,8 +1081,10 @@ struct cifsFileInfo *find_writable_file(struct cifsInodeInfo *cifs_inode)
read_lock(&GlobalSMBSeslock);
refind_writable:
list_for_each_entry(open_file, &cifs_inode->openFileList, flist) {
- if (open_file->closePend)
+ if (open_file->closePend ||
+ (!any_available && open_file->pid != current->tgid))
continue;
+
if (open_file->pfile &&
((open_file->pfile->f_flags & O_RDWR) ||
(open_file->pfile->f_flags & O_WRONLY))) {
@@ -1131,6 +1134,11 @@ refind_writable:
of the loop here. */
}
}
+ /* couldn't find useable FH with same pid, try any available */
+ if (!any_available) {
+ any_available = true;
+ goto refind_writable;
+ }
read_unlock(&GlobalSMBSeslock);
return NULL;
}
@@ -1447,49 +1455,52 @@ static int cifs_writepage(struct page *page, struct writeback_control *wbc)
return rc;
}
-static int cifs_commit_write(struct file *file, struct page *page,
- unsigned offset, unsigned to)
+static int cifs_write_end(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned copied,
+ struct page *page, void *fsdata)
{
- int xid;
- int rc = 0;
- struct inode *inode = page->mapping->host;
- loff_t position = ((loff_t)page->index << PAGE_CACHE_SHIFT) + to;
- char *page_data;
+ int rc;
+ struct inode *inode = mapping->host;
- xid = GetXid();
- cFYI(1, ("commit write for page %p up to position %lld for %d",
- page, position, to));
- spin_lock(&inode->i_lock);
- if (position > inode->i_size)
- i_size_write(inode, position);
+ cFYI(1, ("write_end for page %p from pos %lld with %d bytes",
+ page, pos, copied));
+
+ if (!PageUptodate(page) && copied == PAGE_CACHE_SIZE)
+ SetPageUptodate(page);
- spin_unlock(&inode->i_lock);
if (!PageUptodate(page)) {
- position = ((loff_t)page->index << PAGE_CACHE_SHIFT) + offset;
- /* can not rely on (or let) writepage write this data */
- if (to < offset) {
- cFYI(1, ("Illegal offsets, can not copy from %d to %d",
- offset, to));
- FreeXid(xid);
- return rc;
- }
+ char *page_data;
+ unsigned offset = pos & (PAGE_CACHE_SIZE - 1);
+ int xid;
+
+ xid = GetXid();
/* this is probably better than directly calling
partialpage_write since in this function the file handle is
known which we might as well leverage */
/* BB check if anything else missing out of ppw
such as updating last write time */
page_data = kmap(page);
- rc = cifs_write(file, page_data + offset, to-offset,
- &position);
- if (rc > 0)
- rc = 0;
- /* else if (rc < 0) should we set writebehind rc? */
+ rc = cifs_write(file, page_data + offset, copied, &pos);
+ /* if (rc < 0) should we set writebehind rc? */
kunmap(page);
+
+ FreeXid(xid);
} else {
+ rc = copied;
+ pos += copied;
set_page_dirty(page);
}
- FreeXid(xid);
+ if (rc > 0) {
+ spin_lock(&inode->i_lock);
+ if (pos > inode->i_size)
+ i_size_write(inode, pos);
+ spin_unlock(&inode->i_lock);
+ }
+
+ unlock_page(page);
+ page_cache_release(page);
+
return rc;
}
@@ -2035,49 +2046,44 @@ bool is_size_safe_to_change(struct cifsInodeInfo *cifsInode, __u64 end_of_file)
return true;
}
-static int cifs_prepare_write(struct file *file, struct page *page,
- unsigned from, unsigned to)
+static int cifs_write_begin(struct file *file, struct address_space *mapping,
+ loff_t pos, unsigned len, unsigned flags,
+ struct page **pagep, void **fsdata)
{
- int rc = 0;
- loff_t i_size;
- loff_t offset;
+ pgoff_t index = pos >> PAGE_CACHE_SHIFT;
+ loff_t offset = pos & (PAGE_CACHE_SIZE - 1);
- cFYI(1, ("prepare write for page %p from %d to %d", page, from, to));
- if (PageUptodate(page))
+ cFYI(1, ("write_begin from %lld len %d", (long long)pos, len));
+
+ *pagep = __grab_cache_page(mapping, index);
+ if (!*pagep)
+ return -ENOMEM;
+
+ if (PageUptodate(*pagep))
return 0;
/* If we are writing a full page it will be up to date,
no need to read from the server */
- if ((to == PAGE_CACHE_SIZE) && (from == 0)) {
- SetPageUptodate(page);
+ if (len == PAGE_CACHE_SIZE && flags & AOP_FLAG_UNINTERRUPTIBLE)
return 0;
- }
- offset = (loff_t)page->index << PAGE_CACHE_SHIFT;
- i_size = i_size_read(page->mapping->host);
+ if ((file->f_flags & O_ACCMODE) != O_WRONLY) {
+ int rc;
- if ((offset >= i_size) ||
- ((from == 0) && (offset + to) >= i_size)) {
- /*
- * We don't need to read data beyond the end of the file.
- * zero it, and set the page uptodate
- */
- simple_prepare_write(file, page, from, to);
- SetPageUptodate(page);
- } else if ((file->f_flags & O_ACCMODE) != O_WRONLY) {
/* might as well read a page, it is fast enough */
- rc = cifs_readpage_worker(file, page, &offset);
+ rc = cifs_readpage_worker(file, *pagep, &offset);
+
+ /* we do not need to pass errors back
+ e.g. if we do not have read access to the file
+ because cifs_write_end will attempt synchronous writes
+ -- shaggy */
} else {
/* we could try using another file handle if there is one -
but how would we lock it to prevent close of that handle
racing with this read? In any case
- this will be written out by commit_write so is fine */
+ this will be written out by write_end so is fine */
}
- /* we do not need to pass errors back
- e.g. if we do not have read access to the file
- because cifs_commit_write will do the right thing. -- shaggy */
-
return 0;
}
@@ -2086,8 +2092,8 @@ const struct address_space_operations cifs_addr_ops = {
.readpages = cifs_readpages,
.writepage = cifs_writepage,
.writepages = cifs_writepages,
- .prepare_write = cifs_prepare_write,
- .commit_write = cifs_commit_write,
+ .write_begin = cifs_write_begin,
+ .write_end = cifs_write_end,
.set_page_dirty = __set_page_dirty_nobuffers,
/* .sync_page = cifs_sync_page, */
/* .direct_IO = */
@@ -2102,8 +2108,8 @@ const struct address_space_operations cifs_addr_ops_smallbuf = {
.readpage = cifs_readpage,
.writepage = cifs_writepage,
.writepages = cifs_writepages,
- .prepare_write = cifs_prepare_write,
- .commit_write = cifs_commit_write,
+ .write_begin = cifs_write_begin,
+ .write_end = cifs_write_end,
.set_page_dirty = __set_page_dirty_nobuffers,
/* .sync_page = cifs_sync_page, */
/* .direct_IO = */