diff options
| -rw-r--r-- | fs/netfs/direct_write.c | 28 | ||||
| -rw-r--r-- | include/linux/pagemap.h | 2 | ||||
| -rw-r--r-- | mm/filemap.c | 54 |
3 files changed, 80 insertions, 4 deletions
diff --git a/fs/netfs/direct_write.c b/fs/netfs/direct_write.c index bee047e20f5d..2b81cd4aae6e 100644 --- a/fs/netfs/direct_write.c +++ b/fs/netfs/direct_write.c @@ -132,12 +132,14 @@ out: ssize_t netfs_unbuffered_write_iter(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; - struct inode *inode = file->f_mapping->host; + struct address_space *mapping = file->f_mapping; + struct inode *inode = mapping->host; struct netfs_inode *ictx = netfs_inode(inode); - unsigned long long end; ssize_t ret; + loff_t pos = iocb->ki_pos; + unsigned long long end = pos + iov_iter_count(from) - 1; - _enter("%llx,%zx,%llx", iocb->ki_pos, iov_iter_count(from), i_size_read(inode)); + _enter("%llx,%zx,%llx", pos, iov_iter_count(from), i_size_read(inode)); if (!iov_iter_count(from)) return 0; @@ -157,7 +159,25 @@ ssize_t netfs_unbuffered_write_iter(struct kiocb *iocb, struct iov_iter *from) ret = file_update_time(file); if (ret < 0) goto out; - ret = kiocb_invalidate_pages(iocb, iov_iter_count(from)); + if (iocb->ki_flags & IOCB_NOWAIT) { + /* We could block if there are any pages in the range. */ + ret = -EAGAIN; + if (filemap_range_has_page(mapping, pos, end)) + if (filemap_invalidate_inode(inode, true, pos, end)) + goto out; + } else { + ret = filemap_write_and_wait_range(mapping, pos, end); + if (ret < 0) + goto out; + } + + /* + * After a write we want buffered reads to be sure to go to disk to get + * the new data. We invalidate clean cached page from the region we're + * about to write. We do this *before* the write so that we can return + * without clobbering -EIOCBQUEUED from ->direct_IO(). + */ + ret = filemap_invalidate_inode(inode, true, pos, end); if (ret < 0) goto out; end = iocb->ki_pos + iov_iter_count(from); diff --git a/include/linux/pagemap.h b/include/linux/pagemap.h index 2df35e65557d..c5e33e2ca48a 100644 --- a/include/linux/pagemap.h +++ b/include/linux/pagemap.h @@ -40,6 +40,8 @@ int filemap_fdatawait_keep_errors(struct address_space *mapping); int filemap_fdatawait_range(struct address_space *, loff_t lstart, loff_t lend); int filemap_fdatawait_range_keep_errors(struct address_space *mapping, loff_t start_byte, loff_t end_byte); +int filemap_invalidate_inode(struct inode *inode, bool flush, + loff_t start, loff_t end); static inline int filemap_fdatawait(struct address_space *mapping) { diff --git a/mm/filemap.c b/mm/filemap.c index 9a2e28bf298a..1d6b3a369077 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -4134,6 +4134,60 @@ bool filemap_release_folio(struct folio *folio, gfp_t gfp) } EXPORT_SYMBOL(filemap_release_folio); +/** + * filemap_invalidate_inode - Invalidate/forcibly write back a range of an inode's pagecache + * @inode: The inode to flush + * @flush: Set to write back rather than simply invalidate. + * @start: First byte to in range. + * @end: Last byte in range (inclusive), or LLONG_MAX for everything from start + * onwards. + * + * Invalidate all the folios on an inode that contribute to the specified + * range, possibly writing them back first. Whilst the operation is + * undertaken, the invalidate lock is held to prevent new folios from being + * installed. + */ +int filemap_invalidate_inode(struct inode *inode, bool flush, + loff_t start, loff_t end) +{ + struct address_space *mapping = inode->i_mapping; + pgoff_t first = start >> PAGE_SHIFT; + pgoff_t last = end >> PAGE_SHIFT; + pgoff_t nr = end == LLONG_MAX ? ULONG_MAX : last - first + 1; + + if (!mapping || !mapping->nrpages || end < start) + goto out; + + /* Prevent new folios from being added to the inode. */ + filemap_invalidate_lock(mapping); + + if (!mapping->nrpages) + goto unlock; + + unmap_mapping_pages(mapping, first, nr, false); + + /* Write back the data if we're asked to. */ + if (flush) { + struct writeback_control wbc = { + .sync_mode = WB_SYNC_ALL, + .nr_to_write = LONG_MAX, + .range_start = start, + .range_end = end, + }; + + filemap_fdatawrite_wbc(mapping, &wbc); + } + + /* Wait for writeback to complete on all folios and discard. */ + truncate_inode_pages_range(mapping, start, end); + +unlock: + filemap_invalidate_unlock(mapping); +out: + return filemap_check_errors(mapping); +} +EXPORT_SYMBOL_GPL(filemap_invalidate_inode); + #ifdef CONFIG_CACHESTAT_SYSCALL /** * filemap_cachestat() - compute the page cache statistics of a mapping |