diff options
Diffstat (limited to 'fs/nfs/write.c')
| -rw-r--r-- | fs/nfs/write.c | 31 |
1 files changed, 23 insertions, 8 deletions
diff --git a/fs/nfs/write.c b/fs/nfs/write.c index a2c7c28049d5..f1bdb7254776 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -888,6 +888,28 @@ out: return PageUptodate(page) != 0; } +/* If we know the page is up to date, and we're not using byte range locks (or + * if we have the whole file locked for writing), it may be more efficient to + * extend the write to cover the entire page in order to avoid fragmentation + * inefficiencies. + * + * If the file is opened for synchronous writes or if we have a write delegation + * from the server then we can just skip the rest of the checks. + */ +static int nfs_can_extend_write(struct file *file, struct page *page, struct inode *inode) +{ + if (file->f_flags & O_DSYNC) + return 0; + if (NFS_PROTO(inode)->have_delegation(inode, FMODE_WRITE)) + return 1; + if (nfs_write_pageuptodate(page, inode) && (inode->i_flock == NULL || + (inode->i_flock->fl_start == 0 && + inode->i_flock->fl_end == OFFSET_MAX && + inode->i_flock->fl_type != F_RDLCK))) + return 1; + return 0; +} + /* * Update and possibly write a cached page of an NFS file. * @@ -908,14 +930,7 @@ int nfs_updatepage(struct file *file, struct page *page, file->f_path.dentry->d_name.name, count, (long long)(page_file_offset(page) + offset)); - /* If we're not using byte range locks, and we know the page - * is up to date, it may be more efficient to extend the write - * to cover the entire page in order to avoid fragmentation - * inefficiencies. - */ - if (nfs_write_pageuptodate(page, inode) && - inode->i_flock == NULL && - !(file->f_flags & O_DSYNC)) { + if (nfs_can_extend_write(file, page, inode)) { count = max(count + offset, nfs_page_length(page)); offset = 0; } |