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authorDavid Sterba <dsterba@suse.com>2021-10-27 11:42:43 +0300
committerDavid Sterba <dsterba@suse.com>2021-10-29 14:03:05 +0300
commit55276e14df4324ade34583adef110e11d249fb7b (patch)
tree52773e8ed8c8e6350417dc1a137f7026256f09c3 /fs/btrfs/zlib.c
parent56ee254d23c59fd48fb6f192d79858f60cfe2bf6 (diff)
downloadlinux-55276e14df4324ade34583adef110e11d249fb7b.tar.xz
Revert "btrfs: compression: drop kmap/kunmap from zlib"
This reverts commit 696ab562e6df9fbafd6052d8ce4aafcb2ed16069. The kmaps in compression code are still needed and cause crashes on 32bit machines (ARM, x86). Reproducible eg. by running fstest btrfs/004 with enabled LZO or ZSTD compression. Link: https://lore.kernel.org/all/CAJCQCtT+OuemovPO7GZk8Y8=qtOObr0XTDp8jh4OHD6y84AFxw@mail.gmail.com/ Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=214839 Signed-off-by: David Sterba <dsterba@suse.com>
Diffstat (limited to 'fs/btrfs/zlib.c')
-rw-r--r--fs/btrfs/zlib.c36
1 files changed, 25 insertions, 11 deletions
diff --git a/fs/btrfs/zlib.c b/fs/btrfs/zlib.c
index 8afa90074891..767a0c6c9694 100644
--- a/fs/btrfs/zlib.c
+++ b/fs/btrfs/zlib.c
@@ -126,7 +126,7 @@ int zlib_compress_pages(struct list_head *ws, struct address_space *mapping,
ret = -ENOMEM;
goto out;
}
- cpage_out = page_address(out_page);
+ cpage_out = kmap(out_page);
pages[0] = out_page;
nr_pages = 1;
@@ -148,22 +148,26 @@ int zlib_compress_pages(struct list_head *ws, struct address_space *mapping,
int i;
for (i = 0; i < in_buf_pages; i++) {
- if (in_page)
+ if (in_page) {
+ kunmap(in_page);
put_page(in_page);
+ }
in_page = find_get_page(mapping,
start >> PAGE_SHIFT);
- data_in = page_address(in_page);
+ data_in = kmap(in_page);
memcpy(workspace->buf + i * PAGE_SIZE,
data_in, PAGE_SIZE);
start += PAGE_SIZE;
}
workspace->strm.next_in = workspace->buf;
} else {
- if (in_page)
+ if (in_page) {
+ kunmap(in_page);
put_page(in_page);
+ }
in_page = find_get_page(mapping,
start >> PAGE_SHIFT);
- data_in = page_address(in_page);
+ data_in = kmap(in_page);
start += PAGE_SIZE;
workspace->strm.next_in = data_in;
}
@@ -192,6 +196,7 @@ int zlib_compress_pages(struct list_head *ws, struct address_space *mapping,
* the stream end if required
*/
if (workspace->strm.avail_out == 0) {
+ kunmap(out_page);
if (nr_pages == nr_dest_pages) {
out_page = NULL;
ret = -E2BIG;
@@ -202,7 +207,7 @@ int zlib_compress_pages(struct list_head *ws, struct address_space *mapping,
ret = -ENOMEM;
goto out;
}
- cpage_out = page_address(out_page);
+ cpage_out = kmap(out_page);
pages[nr_pages] = out_page;
nr_pages++;
workspace->strm.avail_out = PAGE_SIZE;
@@ -229,6 +234,7 @@ int zlib_compress_pages(struct list_head *ws, struct address_space *mapping,
goto out;
} else if (workspace->strm.avail_out == 0) {
/* get another page for the stream end */
+ kunmap(out_page);
if (nr_pages == nr_dest_pages) {
out_page = NULL;
ret = -E2BIG;
@@ -239,7 +245,7 @@ int zlib_compress_pages(struct list_head *ws, struct address_space *mapping,
ret = -ENOMEM;
goto out;
}
- cpage_out = page_address(out_page);
+ cpage_out = kmap(out_page);
pages[nr_pages] = out_page;
nr_pages++;
workspace->strm.avail_out = PAGE_SIZE;
@@ -258,8 +264,13 @@ int zlib_compress_pages(struct list_head *ws, struct address_space *mapping,
*total_in = workspace->strm.total_in;
out:
*out_pages = nr_pages;
- if (in_page)
+ if (out_page)
+ kunmap(out_page);
+
+ if (in_page) {
+ kunmap(in_page);
put_page(in_page);
+ }
return ret;
}
@@ -276,7 +287,7 @@ int zlib_decompress_bio(struct list_head *ws, struct compressed_bio *cb)
unsigned long buf_start;
struct page **pages_in = cb->compressed_pages;
- data_in = page_address(pages_in[page_in_index]);
+ data_in = kmap(pages_in[page_in_index]);
workspace->strm.next_in = data_in;
workspace->strm.avail_in = min_t(size_t, srclen, PAGE_SIZE);
workspace->strm.total_in = 0;
@@ -298,6 +309,7 @@ int zlib_decompress_bio(struct list_head *ws, struct compressed_bio *cb)
if (Z_OK != zlib_inflateInit2(&workspace->strm, wbits)) {
pr_warn("BTRFS: inflateInit failed\n");
+ kunmap(pages_in[page_in_index]);
return -EIO;
}
while (workspace->strm.total_in < srclen) {
@@ -324,13 +336,13 @@ int zlib_decompress_bio(struct list_head *ws, struct compressed_bio *cb)
if (workspace->strm.avail_in == 0) {
unsigned long tmp;
-
+ kunmap(pages_in[page_in_index]);
page_in_index++;
if (page_in_index >= total_pages_in) {
data_in = NULL;
break;
}
- data_in = page_address(pages_in[page_in_index]);
+ data_in = kmap(pages_in[page_in_index]);
workspace->strm.next_in = data_in;
tmp = srclen - workspace->strm.total_in;
workspace->strm.avail_in = min(tmp, PAGE_SIZE);
@@ -342,6 +354,8 @@ int zlib_decompress_bio(struct list_head *ws, struct compressed_bio *cb)
ret = 0;
done:
zlib_inflateEnd(&workspace->strm);
+ if (data_in)
+ kunmap(pages_in[page_in_index]);
if (!ret)
zero_fill_bio(cb->orig_bio);
return ret;