From 8273d5d4c28a9fde68f830cc6ff61e37e8ae1dca Mon Sep 17 00:00:00 2001 From: Anton Altaparmakov Date: Thu, 8 Sep 2005 22:00:33 +0100 Subject: [PATCH] NTFS: Fix fs/ntfs/aops.c::ntfs_{read,write}_block() to handle the case where a concurrent truncate has truncated the runlist under our feet. Signed-off-by: Anton Altaparmakov --- fs/ntfs/ChangeLog | 2 ++ fs/ntfs/aops.c | 51 +++++++++++++++++++++++++++++++++++++---------- 2 files changed, 42 insertions(+), 11 deletions(-) diff --git a/fs/ntfs/ChangeLog b/fs/ntfs/ChangeLog index 10fc2385ef..7f24cb19c6 100644 --- a/fs/ntfs/ChangeLog +++ b/fs/ntfs/ChangeLog @@ -84,6 +84,8 @@ ToDo/Notes: - Optimize fs/ntfs/aops.c::ntfs_write_block() by extending the page lock protection over the buffer submission for i/o which allows the removal of the get_bh()/put_bh() pairs for each buffer. + - Fix fs/ntfs/aops.c::ntfs_{read,write}_block() to handle the case + where a concurrent truncate has truncated the runlist under our feet. 2.1.23 - Implement extension of resident files and make writing safe as well as many bug fixes, cleanups, and enhancements... diff --git a/fs/ntfs/aops.c b/fs/ntfs/aops.c index 821dad7d14..59389a8801 100644 --- a/fs/ntfs/aops.c +++ b/fs/ntfs/aops.c @@ -204,6 +204,7 @@ static int ntfs_read_block(struct page *page) nr = i = 0; do { u8 *kaddr; + int err; if (unlikely(buffer_uptodate(bh))) continue; @@ -211,6 +212,7 @@ static int ntfs_read_block(struct page *page) arr[nr++] = bh; continue; } + err = 0; bh->b_bdev = vol->sb->s_bdev; /* Is the block within the allowed limits? */ if (iblock < lblock) { @@ -252,7 +254,6 @@ lock_retry_remap: goto handle_hole; /* If first try and runlist unmapped, map and retry. */ if (!is_retry && lcn == LCN_RL_NOT_MAPPED) { - int err; is_retry = TRUE; /* * Attempt to map runlist, dropping lock for @@ -263,20 +264,30 @@ lock_retry_remap: if (likely(!err)) goto lock_retry_remap; rl = NULL; - lcn = err; } else if (!rl) up_read(&ni->runlist.lock); + /* + * If buffer is outside the runlist, treat it as a + * hole. This can happen due to concurrent truncate + * for example. + */ + if (err == -ENOENT || lcn == LCN_ENOENT) { + err = 0; + goto handle_hole; + } /* Hard error, zero out region. */ + if (!err) + err = -EIO; bh->b_blocknr = -1; SetPageError(page); ntfs_error(vol->sb, "Failed to read from inode 0x%lx, " "attribute type 0x%x, vcn 0x%llx, " "offset 0x%x because its location on " "disk could not be determined%s " - "(error code %lli).", ni->mft_no, + "(error code %i).", ni->mft_no, ni->type, (unsigned long long)vcn, vcn_ofs, is_retry ? " even after " - "retrying" : "", (long long)lcn); + "retrying" : "", err); } /* * Either iblock was outside lblock limits or @@ -289,9 +300,10 @@ handle_hole: handle_zblock: kaddr = kmap_atomic(page, KM_USER0); memset(kaddr + i * blocksize, 0, blocksize); - flush_dcache_page(page); kunmap_atomic(kaddr, KM_USER0); - set_buffer_uptodate(bh); + flush_dcache_page(page); + if (likely(!err)) + set_buffer_uptodate(bh); } while (i++, iblock++, (bh = bh->b_this_page) != head); /* Release the lock if we took it. */ @@ -711,20 +723,37 @@ lock_retry_remap: if (likely(!err)) goto lock_retry_remap; rl = NULL; - lcn = err; } else if (!rl) up_read(&ni->runlist.lock); + /* + * If buffer is outside the runlist, truncate has cut it out + * of the runlist. Just clean and clear the buffer and set it + * uptodate so it can get discarded by the VM. + */ + if (err == -ENOENT || lcn == LCN_ENOENT) { + u8 *kaddr; + + bh->b_blocknr = -1; + clear_buffer_dirty(bh); + kaddr = kmap_atomic(page, KM_USER0); + memset(kaddr + bh_offset(bh), 0, blocksize); + kunmap_atomic(kaddr, KM_USER0); + flush_dcache_page(page); + set_buffer_uptodate(bh); + err = 0; + continue; + } /* Failed to map the buffer, even after retrying. */ + if (!err) + err = -EIO; bh->b_blocknr = -1; ntfs_error(vol->sb, "Failed to write to inode 0x%lx, " "attribute type 0x%x, vcn 0x%llx, offset 0x%x " "because its location on disk could not be " - "determined%s (error code %lli).", ni->mft_no, + "determined%s (error code %i).", ni->mft_no, ni->type, (unsigned long long)vcn, vcn_ofs, is_retry ? " even after " - "retrying" : "", (long long)lcn); - if (!err) - err = -EIO; + "retrying" : "", err); break; } while (block++, (bh = bh->b_this_page) != head); -- 2.39.5