Messages in this thread Patch in this message | | | From | Anton Altaparmakov <> | Subject | Re: [Linux-NTFS-Dev] 2.6.23 regression: second access of empty ntfs file leads to D state hang | Date | Fri, 2 Nov 2007 19:22:13 +0000 |
| |
Hi Mike,
On 30 Oct 2007, at 09:23, Anton Altaparmakov wrote: > On 30 Oct 2007, at 08:00, Mike Galbraith wrote: >> On Mon, 2007-10-29 at 16:18 +0100, Mike Galbraith wrote: >> Not being very good at walking away from unsolved mysteries, I >> chased it >> down. The problem is that... >> commit[a32ea1e1f925399e0d81ca3f7394a44a6dafa12c] Fix read/truncate >> race >> ...calls ntfs_readpage() for a zero i_size inode, which it isn't >> accustomed to. > > Great, thanks for doing that! > >> Below is the hammer which made my box a happy camper again. > > Yes that will fix it but the complete solution is more involved as > there are three related bugs which explain why you were getting the > hangs after the error... I will make a patch for all of these in > the next few days...
Attached is a patch that should fix this and the other related issues I found.
Would you be able to test it in your setup? Thanks a lot in advance!
Best regards,
Anton -- Anton Altaparmakov <aia21 at cam.ac.uk> (replace at with @) Unix Support, Computing Service, University of Cambridge, CB2 3QH, UK Linux NTFS maintainer, http://www.linux-ntfs.org/
diff --git a/fs/ntfs/aops.c b/fs/ntfs/aops.c index cfdc790..4e42d4e 100644 --- a/fs/ntfs/aops.c +++ b/fs/ntfs/aops.c @@ -405,6 +405,14 @@ static int ntfs_readpage(struct file *file, struct page *page) retry_readpage: BUG_ON(!PageLocked(page)); + i_size = i_size_read(vi); + /* Is the page fully outside i_size? (truncate in progress) */ + if (unlikely(page->index >= (i_size + PAGE_CACHE_SIZE - 1) >> + PAGE_CACHE_SHIFT)) { + zero_user_page(page, 0, PAGE_CACHE_SIZE, KM_USER0); + ntfs_debug("Read outside i_size - truncated?"); + goto done; + } /* * This can potentially happen because we clear PageUptodate() during * ntfs_writepage() of MstProtected() attributes. diff --git a/fs/ntfs/attrib.c b/fs/ntfs/attrib.c index 92dabdc..50d3b0c 100644 --- a/fs/ntfs/attrib.c +++ b/fs/ntfs/attrib.c @@ -179,10 +179,7 @@ int ntfs_map_runlist_nolock(ntfs_inode *ni, VCN vcn, ntfs_attr_search_ctx *ctx) * ntfs_mapping_pairs_decompress() fails. */ end_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn) + 1; - if (!a->data.non_resident.lowest_vcn && end_vcn == 1) - end_vcn = sle64_to_cpu(a->data.non_resident.allocated_size) >> - ni->vol->cluster_size_bits; - if (unlikely(vcn >= end_vcn)) { + if (unlikely(vcn && vcn >= end_vcn)) { err = -ENOENT; goto err_out; } diff --git a/fs/ntfs/compress.c b/fs/ntfs/compress.c index d98daf5..d1619d0 100644 --- a/fs/ntfs/compress.c +++ b/fs/ntfs/compress.c @@ -561,6 +561,16 @@ int ntfs_read_compressed_block(struct page *page) read_unlock_irqrestore(&ni->size_lock, flags); max_page = ((i_size + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT) - offset; + /* Is the page fully outside i_size? (truncate in progress) */ + if (xpage >= max_page) { + kfree(bhs); + kfree(pages); + zero_user_page(page, 0, PAGE_CACHE_SIZE, KM_USER0); + ntfs_debug("Compressed read outside i_size - truncated?"); + SetPageUptodate(page); + unlock_page(page); + return 0; + } if (nr_pages < max_page) max_page = nr_pages; for (i = 0; i < max_page; i++, offset++) {
| |