diff options
Diffstat (limited to 'fs/cifs/file.c')
-rw-r--r-- | fs/cifs/file.c | 130 |
1 files changed, 68 insertions, 62 deletions
diff --git a/fs/cifs/file.c b/fs/cifs/file.c index cbefe1f..c4a8a06 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 = */ |