To make Btrfs code more robust, several return value checks where memory
allocation can fail are introduced. I use BUG_ON where I don''t know
how
to handle the error properly, which increases the number of using the
notorious BUG_ON, though.
Signed-off-by: Yoshinori Sano <yoshinori.sano@gmail.com>
---
fs/btrfs/compression.c | 6 ++++++
fs/btrfs/extent-tree.c | 2 ++
fs/btrfs/file.c | 8 ++++++--
fs/btrfs/inode.c | 5 +++++
4 files changed, 19 insertions(+), 2 deletions(-)
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 4d2110e..f596554 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -340,6 +340,8 @@ int btrfs_submit_compressed_write(struct inode *inode, u64
start,
WARN_ON(start & ((u64)PAGE_CACHE_SIZE - 1));
cb = kmalloc(compressed_bio_size(root, compressed_len), GFP_NOFS);
+ if (!cb)
+ return -ENOMEM;
atomic_set(&cb->pending_bios, 0);
cb->errors = 0;
cb->inode = inode;
@@ -354,6 +356,10 @@ int btrfs_submit_compressed_write(struct inode *inode, u64
start,
bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev;
bio = compressed_bio_alloc(bdev, first_byte, GFP_NOFS);
+ if (!bio) {
+ kfree(cb);
+ return -ENOMEM;
+ }
bio->bi_private = cb;
bio->bi_end_io = end_compressed_bio_write;
atomic_inc(&cb->pending_bios);
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 565e22d..aed16f4 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -6931,6 +6931,8 @@ static noinline int get_new_locations(struct inode
*reloc_inode,
struct disk_extent *old = exts;
max *= 2;
exts = kzalloc(sizeof(*exts) * max, GFP_NOFS);
+ if (!exts)
+ goto out;
memcpy(exts, old, sizeof(*exts) * nr);
if (old != *extents)
kfree(old);
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c
index b0ff34b..4895ad2 100644
--- a/fs/btrfs/file.c
+++ b/fs/btrfs/file.c
@@ -181,10 +181,14 @@ int btrfs_drop_extent_cache(struct inode *inode, u64
start, u64 end,
testend = 0;
}
while (1) {
- if (!split)
+ if (!split) {
split = alloc_extent_map(GFP_NOFS);
- if (!split2)
+ BUG_ON(!split || IS_ERR(split));
+ }
+ if (!split2) {
split2 = alloc_extent_map(GFP_NOFS);
+ BUG_ON(!split2 || IS_ERR(split2));
+ }
write_lock(&em_tree->lock);
em = lookup_extent_mapping(em_tree, start, len);
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index c9bc0af..40bbe00 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -287,6 +287,7 @@ static noinline int add_async_extent(struct async_cow *cow,
struct async_extent *async_extent;
async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS);
+ BUG_ON(!async_extent);
async_extent->start = start;
async_extent->ram_size = ram_size;
async_extent->compressed_size = compressed_size;
@@ -384,6 +385,7 @@ again:
(BTRFS_I(inode)->force_compress))) {
WARN_ON(pages);
pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS);
+ BUG_ON(!pages);
if (BTRFS_I(inode)->force_compress)
compress_type = BTRFS_I(inode)->force_compress;
@@ -644,6 +646,7 @@ retry:
async_extent->ram_size - 1, 0);
em = alloc_extent_map(GFP_NOFS);
+ BUG_ON(!em || IS_ERR(em));
em->start = async_extent->start;
em->len = async_extent->ram_size;
em->orig_start = em->start;
@@ -820,6 +823,7 @@ static noinline int cow_file_range(struct inode *inode,
BUG_ON(ret);
em = alloc_extent_map(GFP_NOFS);
+ BUG_ON(!em || IS_ERR(em));
em->start = start;
em->orig_start = em->start;
ram_size = ins.offset;
@@ -1169,6 +1173,7 @@ out_check:
struct extent_map_tree *em_tree;
em_tree = &BTRFS_I(inode)->extent_tree;
em = alloc_extent_map(GFP_NOFS);
+ BUG_ON(!em || IS_ERR(em));
em->start = cur_offset;
em->orig_start = em->start;
em->len = num_bytes;
--
1.7.1
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(2011/02/12 20:17), Yoshinori Sano wrote:> To make Btrfs code more robust, several return value checks where memory > allocation can fail are introduced. I use BUG_ON where I don''t know how > to handle the error properly, which increases the number of using the > notorious BUG_ON, though. > > Signed-off-by: Yoshinori Sano <yoshinori.sano@gmail.com> > --- > fs/btrfs/compression.c | 6 ++++++ > fs/btrfs/extent-tree.c | 2 ++ > fs/btrfs/file.c | 8 ++++++-- > fs/btrfs/inode.c | 5 +++++ > 4 files changed, 19 insertions(+), 2 deletions(-) > > diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c > index 4d2110e..f596554 100644 > --- a/fs/btrfs/compression.c > +++ b/fs/btrfs/compression.c > @@ -340,6 +340,8 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start, > > WARN_ON(start & ((u64)PAGE_CACHE_SIZE - 1)); > cb = kmalloc(compressed_bio_size(root, compressed_len), GFP_NOFS); > + if (!cb) > + return -ENOMEM; > atomic_set(&cb->pending_bios, 0); > cb->errors = 0; > cb->inode = inode; > @@ -354,6 +356,10 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start, > bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev; > > bio = compressed_bio_alloc(bdev, first_byte, GFP_NOFS); > + if (!bio) { > + kfree(cb); > + return -ENOMEM; > + } > bio->bi_private = cb; > bio->bi_end_io = end_compressed_bio_write; > atomic_inc(&cb->pending_bios); > diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c > index 565e22d..aed16f4 100644 > --- a/fs/btrfs/extent-tree.c > +++ b/fs/btrfs/extent-tree.c > @@ -6931,6 +6931,8 @@ static noinline int get_new_locations(struct inode *reloc_inode, > struct disk_extent *old = exts; > max *= 2; > exts = kzalloc(sizeof(*exts) * max, GFP_NOFS); > + if (!exts) > + goto out; > memcpy(exts, old, sizeof(*exts) * nr); > if (old != *extents) > kfree(old); > diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c > index b0ff34b..4895ad2 100644 > --- a/fs/btrfs/file.c > +++ b/fs/btrfs/file.c > @@ -181,10 +181,14 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, > testend = 0; > } > while (1) { > - if (!split) > + if (!split) { > split = alloc_extent_map(GFP_NOFS); > - if (!split2) > + BUG_ON(!split || IS_ERR(split));alloc_extent_map() returns only the address or NULL. Therefore, I think that check by IS_ERR() is unnecessary. Regards, Itoh> + } > + if (!split2) { > split2 = alloc_extent_map(GFP_NOFS); > + BUG_ON(!split2 || IS_ERR(split2)); > + } > > write_lock(&em_tree->lock); > em = lookup_extent_mapping(em_tree, start, len); > diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c > index c9bc0af..40bbe00 100644 > --- a/fs/btrfs/inode.c > +++ b/fs/btrfs/inode.c > @@ -287,6 +287,7 @@ static noinline int add_async_extent(struct async_cow *cow, > struct async_extent *async_extent; > > async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS); > + BUG_ON(!async_extent); > async_extent->start = start; > async_extent->ram_size = ram_size; > async_extent->compressed_size = compressed_size; > @@ -384,6 +385,7 @@ again: > (BTRFS_I(inode)->force_compress))) { > WARN_ON(pages); > pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS); > + BUG_ON(!pages); > > if (BTRFS_I(inode)->force_compress) > compress_type = BTRFS_I(inode)->force_compress; > @@ -644,6 +646,7 @@ retry: > async_extent->ram_size - 1, 0); > > em = alloc_extent_map(GFP_NOFS); > + BUG_ON(!em || IS_ERR(em)); > em->start = async_extent->start; > em->len = async_extent->ram_size; > em->orig_start = em->start; > @@ -820,6 +823,7 @@ static noinline int cow_file_range(struct inode *inode, > BUG_ON(ret); > > em = alloc_extent_map(GFP_NOFS); > + BUG_ON(!em || IS_ERR(em)); > em->start = start; > em->orig_start = em->start; > ram_size = ins.offset; > @@ -1169,6 +1173,7 @@ out_check: > struct extent_map_tree *em_tree; > em_tree = &BTRFS_I(inode)->extent_tree; > em = alloc_extent_map(GFP_NOFS); > + BUG_ON(!em || IS_ERR(em)); > em->start = cur_offset; > em->orig_start = em->start; > em->len = num_bytes;-- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Sano-san, (2011/02/14 22:57), Yoshinori Sano wrote:> 2011年2月14日8:57 Tsutomu Itoh <t-itoh@jp.fujitsu.com>: >> (2011/02/12 20:17), Yoshinori Sano wrote: >>> To make Btrfs code more robust, several return value checks where memory >>> allocation can fail are introduced. I use BUG_ON where I don''t know how >>> to handle the error properly, which increases the number of using the >>> notorious BUG_ON, though. >>> >>> Signed-off-by: Yoshinori Sano <yoshinori.sano@gmail.com> >>> --- >>> fs/btrfs/compression.c | 6 ++++++ >>> fs/btrfs/extent-tree.c | 2 ++ >>> fs/btrfs/file.c | 8 ++++++-- >>> fs/btrfs/inode.c | 5 +++++ >>> 4 files changed, 19 insertions(+), 2 deletions(-) >>> >>> diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c >>> index 4d2110e..f596554 100644 >>> --- a/fs/btrfs/compression.c >>> +++ b/fs/btrfs/compression.c >>> @@ -340,6 +340,8 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start, >>> >>> WARN_ON(start & ((u64)PAGE_CACHE_SIZE - 1)); >>> cb = kmalloc(compressed_bio_size(root, compressed_len), GFP_NOFS); >>> + if (!cb) >>> + return -ENOMEM; >>> atomic_set(&cb->pending_bios, 0); >>> cb->errors = 0; >>> cb->inode = inode; >>> @@ -354,6 +356,10 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start, >>> bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev; >>> >>> bio = compressed_bio_alloc(bdev, first_byte, GFP_NOFS); >>> + if (!bio) { >>> + kfree(cb); >>> + return -ENOMEM; >>> + } >>> bio->bi_private = cb; >>> bio->bi_end_io = end_compressed_bio_write; >>> atomic_inc(&cb->pending_bios); >>> diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c >>> index 565e22d..aed16f4 100644 >>> --- a/fs/btrfs/extent-tree.c >>> +++ b/fs/btrfs/extent-tree.c >>> @@ -6931,6 +6931,8 @@ static noinline int get_new_locations(struct inode *reloc_inode, >>> struct disk_extent *old = exts; >>> max *= 2; >>> exts = kzalloc(sizeof(*exts) * max, GFP_NOFS); >>> + if (!exts) >>> + goto out;''ret = -ENOMEM'' is necessary before ''goto out''.>>> memcpy(exts, old, sizeof(*exts) * nr); >>> if (old != *extents) >>> kfree(old); >>> diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c >>> index b0ff34b..4895ad2 100644 >>> --- a/fs/btrfs/file.c >>> +++ b/fs/btrfs/file.c >>> @@ -181,10 +181,14 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, >>> testend = 0; >>> } >>> while (1) { >>> - if (!split) >>> + if (!split) { >>> split = alloc_extent_map(GFP_NOFS); >>> - if (!split2) >>> + BUG_ON(!split || IS_ERR(split)); >> >> alloc_extent_map() returns only the address or NULL. >> Therefore, I think that check by IS_ERR() is unnecessary. >> >> Regards, >> Itoh > > Exactly. IS_ERR is not required. > I should read the alloc_extent_map'' s implementation more deeply. > Thank you.Could you please merge my patch(http://marc.info/?l=linux-btrfs&m=129764438122741&w=2) with your patch, and post it again? Thanks, Itoh> >> >>> + } >>> + if (!split2) { >>> split2 = alloc_extent_map(GFP_NOFS); >>> + BUG_ON(!split2 || IS_ERR(split2)); >>> + } >>> >>> write_lock(&em_tree->lock); >>> em = lookup_extent_mapping(em_tree, start, len); >>> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c >>> index c9bc0af..40bbe00 100644 >>> --- a/fs/btrfs/inode.c >>> +++ b/fs/btrfs/inode.c >>> @@ -287,6 +287,7 @@ static noinline int add_async_extent(struct async_cow *cow, >>> struct async_extent *async_extent; >>> >>> async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS); >>> + BUG_ON(!async_extent); >>> async_extent->start = start; >>> async_extent->ram_size = ram_size; >>> async_extent->compressed_size = compressed_size; >>> @@ -384,6 +385,7 @@ again: >>> (BTRFS_I(inode)->force_compress))) { >>> WARN_ON(pages); >>> pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS); >>> + BUG_ON(!pages); >>> >>> if (BTRFS_I(inode)->force_compress) >>> compress_type = BTRFS_I(inode)->force_compress; >>> @@ -644,6 +646,7 @@ retry: >>> async_extent->ram_size - 1, 0); >>> >>> em = alloc_extent_map(GFP_NOFS); >>> + BUG_ON(!em || IS_ERR(em)); >>> em->start = async_extent->start; >>> em->len = async_extent->ram_size; >>> em->orig_start = em->start; >>> @@ -820,6 +823,7 @@ static noinline int cow_file_range(struct inode *inode, >>> BUG_ON(ret); >>> >>> em = alloc_extent_map(GFP_NOFS); >>> + BUG_ON(!em || IS_ERR(em)); >>> em->start = start; >>> em->orig_start = em->start; >>> ram_size = ins.offset; >>> @@ -1169,6 +1173,7 @@ out_check: >>> struct extent_map_tree *em_tree; >>> em_tree = &BTRFS_I(inode)->extent_tree; >>> em = alloc_extent_map(GFP_NOFS); >>> + BUG_ON(!em || IS_ERR(em)); >>> em->start = cur_offset; >>> em->orig_start = em->start; >>> em->len = num_bytes; >> >> >-- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
2011年2月15日9:14 Tsutomu Itoh <t-itoh@jp.fujitsu.com>:> Sano-san, > > (2011/02/14 22:57), Yoshinori Sano wrote: >> 2011年2月14日8:57 Tsutomu Itoh <t-itoh@jp.fujitsu.com>: >>> (2011/02/12 20:17), Yoshinori Sano wrote: >>>> To make Btrfs code more robust, several return value checks where memory >>>> allocation can fail are introduced. I use BUG_ON where I don''t know how >>>> to handle the error properly, which increases the number of using the >>>> notorious BUG_ON, though. >>>> >>>> Signed-off-by: Yoshinori Sano <yoshinori.sano@gmail.com> >>>> --- >>>> fs/btrfs/compression.c | 6 ++++++ >>>> fs/btrfs/extent-tree.c | 2 ++ >>>> fs/btrfs/file.c | 8 ++++++-- >>>> fs/btrfs/inode.c | 5 +++++ >>>> 4 files changed, 19 insertions(+), 2 deletions(-) >>>> >>>> diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c >>>> index 4d2110e..f596554 100644 >>>> --- a/fs/btrfs/compression.c >>>> +++ b/fs/btrfs/compression.c >>>> @@ -340,6 +340,8 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start, >>>> >>>> WARN_ON(start & ((u64)PAGE_CACHE_SIZE - 1)); >>>> cb = kmalloc(compressed_bio_size(root, compressed_len), GFP_NOFS); >>>> + if (!cb) >>>> + return -ENOMEM; >>>> atomic_set(&cb->pending_bios, 0); >>>> cb->errors = 0; >>>> cb->inode = inode; >>>> @@ -354,6 +356,10 @@ int btrfs_submit_compressed_write(struct inode *inode, u64 start, >>>> bdev = BTRFS_I(inode)->root->fs_info->fs_devices->latest_bdev; >>>> >>>> bio = compressed_bio_alloc(bdev, first_byte, GFP_NOFS); >>>> + if (!bio) { >>>> + kfree(cb); >>>> + return -ENOMEM; >>>> + } >>>> bio->bi_private = cb; >>>> bio->bi_end_io = end_compressed_bio_write; >>>> atomic_inc(&cb->pending_bios); >>>> diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c >>>> index 565e22d..aed16f4 100644 >>>> --- a/fs/btrfs/extent-tree.c >>>> +++ b/fs/btrfs/extent-tree.c >>>> @@ -6931,6 +6931,8 @@ static noinline int get_new_locations(struct inode *reloc_inode, >>>> struct disk_extent *old = exts; >>>> max *= 2; >>>> exts = kzalloc(sizeof(*exts) * max, GFP_NOFS); >>>> + if (!exts) >>>> + goto out; > > ''ret = -ENOMEM'' is necessary before ''goto out''.I''ll keep in mind to fix this too.> >>>> memcpy(exts, old, sizeof(*exts) * nr); >>>> if (old != *extents) >>>> kfree(old); >>>> diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c >>>> index b0ff34b..4895ad2 100644 >>>> --- a/fs/btrfs/file.c >>>> +++ b/fs/btrfs/file.c >>>> @@ -181,10 +181,14 @@ int btrfs_drop_extent_cache(struct inode *inode, u64 start, u64 end, >>>> testend = 0; >>>> } >>>> while (1) { >>>> - if (!split) >>>> + if (!split) { >>>> split = alloc_extent_map(GFP_NOFS); >>>> - if (!split2) >>>> + BUG_ON(!split || IS_ERR(split)); >>> >>> alloc_extent_map() returns only the address or NULL. >>> Therefore, I think that check by IS_ERR() is unnecessary. >>> >>> Regards, >>> Itoh >> >> Exactly. IS_ERR is not required. >> I should read the alloc_extent_map'' s implementation more deeply. >> Thank you. > > Could you please merge my patch(http://marc.info/?l=linux-btrfs&m=129764438122741&w=2) > with your patch, and post it again?Yes, this is a good idea :) I''ll merge your patch and post it again later. Thank you.> > Thanks, > Itoh > >> >>> >>>> + } >>>> + if (!split2) { >>>> split2 = alloc_extent_map(GFP_NOFS); >>>> + BUG_ON(!split2 || IS_ERR(split2)); >>>> + } >>>> >>>> write_lock(&em_tree->lock); >>>> em = lookup_extent_mapping(em_tree, start, len); >>>> diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c >>>> index c9bc0af..40bbe00 100644 >>>> --- a/fs/btrfs/inode.c >>>> +++ b/fs/btrfs/inode.c >>>> @@ -287,6 +287,7 @@ static noinline int add_async_extent(struct async_cow *cow, >>>> struct async_extent *async_extent; >>>> >>>> async_extent = kmalloc(sizeof(*async_extent), GFP_NOFS); >>>> + BUG_ON(!async_extent); >>>> async_extent->start = start; >>>> async_extent->ram_size = ram_size; >>>> async_extent->compressed_size = compressed_size; >>>> @@ -384,6 +385,7 @@ again: >>>> (BTRFS_I(inode)->force_compress))) { >>>> WARN_ON(pages); >>>> pages = kzalloc(sizeof(struct page *) * nr_pages, GFP_NOFS); >>>> + BUG_ON(!pages); >>>> >>>> if (BTRFS_I(inode)->force_compress) >>>> compress_type = BTRFS_I(inode)->force_compress; >>>> @@ -644,6 +646,7 @@ retry: >>>> async_extent->ram_size - 1, 0); >>>> >>>> em = alloc_extent_map(GFP_NOFS); >>>> + BUG_ON(!em || IS_ERR(em)); >>>> em->start = async_extent->start; >>>> em->len = async_extent->ram_size; >>>> em->orig_start = em->start; >>>> @@ -820,6 +823,7 @@ static noinline int cow_file_range(struct inode *inode, >>>> BUG_ON(ret); >>>> >>>> em = alloc_extent_map(GFP_NOFS); >>>> + BUG_ON(!em || IS_ERR(em)); >>>> em->start = start; >>>> em->orig_start = em->start; >>>> ram_size = ins.offset; >>>> @@ -1169,6 +1173,7 @@ out_check: >>>> struct extent_map_tree *em_tree; >>>> em_tree = &BTRFS_I(inode)->extent_tree; >>>> em = alloc_extent_map(GFP_NOFS); >>>> + BUG_ON(!em || IS_ERR(em)); >>>> em->start = cur_offset; >>>> em->orig_start = em->start; >>>> em->len = num_bytes; >>> >>> >> > >-- Yoshinori Sano <yoshinori.sano@gmail.com> -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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