From 16073605bb947e6acfa3b13b6280a90fed9b717a Mon Sep 17 00:00:00 2001 From: David Marcin Date: Wed, 9 Nov 2011 13:23:28 -0800 Subject: [PATCH 20/35] btrfs-progs: Fix error handling for failed reads in restore tool when mirrors exist --- restore.c | 11 +++++++---- 1 files changed, 7 insertions(+), 4 deletions(-) diff --git a/restore.c b/restore.c index 4dabae2..389b107 100644 --- a/restore.c +++ b/restore.c @@ -197,7 +197,7 @@ static int copy_one_extent(struct btrfs_root *root, int fd, int compress; int ret; int dev_fd; - int mirror_num = 0; + int mirror_num = 1; int num_copies; compress = btrfs_file_extent_compression(leaf, fi); @@ -240,14 +240,15 @@ again: if (size_left < length) length = size_left; - size_left -= length; done = pread(dev_fd, inbuf+count, length, dev_bytenr); - if (done < length) { + /* Need both checks, or we miss negative values due to u64 conversion */ + if (done < 0 || done < length) { num_copies = btrfs_num_copies(&root->fs_info->mapping_tree, bytenr, length); mirror_num++; - if (mirror_num >= num_copies) { + /* mirror_num is 1-indexed, so num_copies is a valid mirror. */ + if (mirror_num > num_copies) { ret = -1; fprintf(stderr, "Exhausted mirrors trying to read\n"); goto out; @@ -256,6 +257,8 @@ again: goto again; } + mirror_num = 1; + size_left -= length; count += length; bytenr += length; if (size_left) -- 1.7.6.233.gd79bc