diff options
Diffstat (limited to 'fs/nfs/write.c')
| -rw-r--r-- | fs/nfs/write.c | 24 |
1 files changed, 18 insertions, 6 deletions
diff --git a/fs/nfs/write.c b/fs/nfs/write.c index 522efff3e2c..f55c437124a 100644 --- a/fs/nfs/write.c +++ b/fs/nfs/write.c @@ -665,9 +665,7 @@ zero_page: * then we need to zero any uninitalised data. */ if (req->wb_pgbase == 0 && req->wb_bytes != PAGE_CACHE_SIZE && !PageUptodate(req->wb_page)) - zero_user_page(req->wb_page, req->wb_bytes, - PAGE_CACHE_SIZE - req->wb_bytes, - KM_USER0); + zero_user_segment(req->wb_page, req->wb_bytes, PAGE_CACHE_SIZE); return req; } @@ -699,6 +697,17 @@ int nfs_flush_incompatible(struct file *file, struct page *page) } /* + * If the page cache is marked as unsafe or invalid, then we can't rely on + * the PageUptodate() flag. In this case, we will need to turn off + * write optimisations that depend on the page contents being correct. + */ +static int nfs_write_pageuptodate(struct page *page, struct inode *inode) +{ + return PageUptodate(page) && + !(NFS_I(inode)->cache_validity & (NFS_INO_REVAL_PAGECACHE|NFS_INO_INVALID_DATA)); +} + +/* * Update and possibly write a cached page of an NFS file. * * XXX: Keep an eye on generic_file_read to make sure it doesn't do bad @@ -719,10 +728,13 @@ int nfs_updatepage(struct file *file, struct page *page, (long long)(page_offset(page) +offset)); /* If we're not using byte range locks, and we know the page - * is entirely in cache, it may be more efficient to avoid - * fragmenting write requests. + * 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 (PageUptodate(page) && inode->i_flock == NULL && !(file->f_mode & O_SYNC)) { + if (nfs_write_pageuptodate(page, inode) && + inode->i_flock == NULL && + !(file->f_mode & O_SYNC)) { count = max(count + offset, nfs_page_length(page)); offset = 0; } |