From 4d958295d2c7608c8c695d8fc3e9e9e94bae089b Mon Sep 17 00:00:00 2001 From: Qu Wenruo Date: Tue, 25 Oct 2016 10:11:04 +0800 Subject: btrfs-progs: volumes: Remove BUG_ON in raid56 write routine Remove various BUG_ON in raid56 write routine, including: 1) Memory allocation error Old codes allocates memory when code needs new memory in a loop, and catch the error using BUG_ON(). New codes allocates memory in a allocation loop first, if any failure is caught, freeing already allocated memories then throw -ENOMEM. 2) Write error Change BUG_ON() to correct return value. 3) Validation check Same as write error. Signed-off-by: Qu Wenruo Signed-off-by: David Sterba --- volumes.c | 89 +++++++++++++++++++++++++++++++++++++++++++-------------------- 1 file changed, 61 insertions(+), 28 deletions(-) (limited to 'volumes.c') diff --git a/volumes.c b/volumes.c index b9ca5502..70d89409 100644 --- a/volumes.c +++ b/volumes.c @@ -2063,25 +2063,39 @@ static int rmw_eb(struct btrfs_fs_info *info, return 0; } -static void split_eb_for_raid56(struct btrfs_fs_info *info, - struct extent_buffer *orig_eb, +static int split_eb_for_raid56(struct btrfs_fs_info *info, + struct extent_buffer *orig_eb, struct extent_buffer **ebs, u64 stripe_len, u64 *raid_map, int num_stripes) { - struct extent_buffer *eb; + struct extent_buffer **tmp_ebs; u64 start = orig_eb->start; u64 this_eb_start; int i; - int ret; + int ret = 0; + + tmp_ebs = calloc(num_stripes, sizeof(*tmp_ebs)); + if (!tmp_ebs) + return -ENOMEM; + /* Alloc memory in a row for data stripes */ for (i = 0; i < num_stripes; i++) { if (raid_map[i] >= BTRFS_RAID5_P_STRIPE) break; - eb = calloc(1, sizeof(struct extent_buffer) + stripe_len); - if (!eb) - BUG(); + tmp_ebs[i] = calloc(1, sizeof(**tmp_ebs) + stripe_len); + if (!tmp_ebs[i]) { + ret = -ENOMEM; + goto clean_up; + } + } + + for (i = 0; i < num_stripes; i++) { + struct extent_buffer *eb = tmp_ebs[i]; + + if (raid_map[i] >= BTRFS_RAID5_P_STRIPE) + break; eb->start = raid_map[i]; eb->len = stripe_len; @@ -2095,12 +2109,21 @@ static void split_eb_for_raid56(struct btrfs_fs_info *info, if (start > this_eb_start || start + orig_eb->len < this_eb_start + stripe_len) { ret = rmw_eb(info, eb, orig_eb); - BUG_ON(ret); + if (ret) + goto clean_up; } else { - memcpy(eb->data, orig_eb->data + eb->start - start, stripe_len); + memcpy(eb->data, orig_eb->data + eb->start - start, + stripe_len); } ebs[i] = eb; } + free(tmp_ebs); + return ret; +clean_up: + for (i = 0; i < num_stripes; i++) + free(tmp_ebs[i]); + free(tmp_ebs); + return ret; } int write_raid56_with_parity(struct btrfs_fs_info *info, @@ -2113,15 +2136,20 @@ int write_raid56_with_parity(struct btrfs_fs_info *info, int j; int ret; int alloc_size = eb->len; + void **pointers; - ebs = kmalloc(sizeof(*ebs) * multi->num_stripes, GFP_NOFS); - BUG_ON(!ebs); + ebs = malloc(sizeof(*ebs) * multi->num_stripes); + pointers = malloc(sizeof(*pointers) * multi->num_stripes); + if (!ebs || !pointers) + return -ENOMEM; if (stripe_len > alloc_size) alloc_size = stripe_len; - split_eb_for_raid56(info, eb, ebs, stripe_len, raid_map, - multi->num_stripes); + ret = split_eb_for_raid56(info, eb, ebs, stripe_len, raid_map, + multi->num_stripes); + if (ret) + goto out; for (i = 0; i < multi->num_stripes; i++) { struct extent_buffer *new_eb; @@ -2129,11 +2157,17 @@ int write_raid56_with_parity(struct btrfs_fs_info *info, ebs[i]->dev_bytenr = multi->stripes[i].physical; ebs[i]->fd = multi->stripes[i].dev->fd; multi->stripes[i].dev->total_ios++; - BUG_ON(ebs[i]->start != raid_map[i]); + if (ebs[i]->start != raid_map[i]) { + ret = -EINVAL; + goto out_free_split; + } continue; } - new_eb = kmalloc(sizeof(*eb) + alloc_size, GFP_NOFS); - BUG_ON(!new_eb); + new_eb = malloc(sizeof(*eb) + alloc_size); + if (!new_eb) { + ret = -ENOMEM; + goto out_free_split; + } new_eb->dev_bytenr = multi->stripes[i].physical; new_eb->fd = multi->stripes[i].dev->fd; multi->stripes[i].dev->total_ios++; @@ -2145,12 +2179,6 @@ int write_raid56_with_parity(struct btrfs_fs_info *info, q_eb = new_eb; } if (q_eb) { - void **pointers; - - pointers = kmalloc(sizeof(*pointers) * multi->num_stripes, - GFP_NOFS); - BUG_ON(!pointers); - ebs[multi->num_stripes - 2] = p_eb; ebs[multi->num_stripes - 1] = q_eb; @@ -2158,7 +2186,6 @@ int write_raid56_with_parity(struct btrfs_fs_info *info, pointers[i] = ebs[i]->data; raid6_gen_syndrome(multi->num_stripes, stripe_len, pointers); - kfree(pointers); } else { ebs[multi->num_stripes - 1] = p_eb; memcpy(p_eb->data, ebs[0]->data, stripe_len); @@ -2177,12 +2204,18 @@ int write_raid56_with_parity(struct btrfs_fs_info *info, for (i = 0; i < multi->num_stripes; i++) { ret = write_extent_to_disk(ebs[i]); - BUG_ON(ret); - if (ebs[i] != eb) - kfree(ebs[i]); + if (ret < 0) + goto out_free_split; } - kfree(ebs); +out_free_split: + for (i = 0; i < multi->num_stripes; i++) { + if (ebs[i] != eb) + free(ebs[i]); + } +out: + free(ebs); + free(pointers); - return 0; + return ret; } -- cgit v1.2.3