[PATCH v2 3/3] staging: erofs: support IO read error injection
From: Gao Xiang
Date: Sun Mar 24 2019 - 23:22:42 EST
Used to simulate disk IO read error for testing fatal
error tolerance.
Here are the details,
1) use bio->bi_private to indicate super_block
for non-compressed bios since some (mainly meta)
pages can be of the corresponding bdev inode;
2) get super_block dynamically for compressed bios,
therefore it could not inject bios full of staging
pages, yet it doesn't affect the normal usage.
Signed-off-by: Gao Xiang <gaoxiang25@xxxxxxxxxx>
---
.../staging/erofs/Documentation/filesystems/erofs.txt | 1 +
drivers/staging/erofs/data.c | 18 ++++++++++++------
drivers/staging/erofs/internal.h | 6 ++++--
drivers/staging/erofs/super.c | 3 ++-
drivers/staging/erofs/unzip_vle.c | 14 +++++++++-----
5 files changed, 28 insertions(+), 14 deletions(-)
diff --git a/drivers/staging/erofs/Documentation/filesystems/erofs.txt b/drivers/staging/erofs/Documentation/filesystems/erofs.txt
index 961ec4da7705..74cf84ac48a3 100644
--- a/drivers/staging/erofs/Documentation/filesystems/erofs.txt
+++ b/drivers/staging/erofs/Documentation/filesystems/erofs.txt
@@ -60,6 +60,7 @@ fault_injection=%d Enable fault injection in all supported types with
specified injection rate. Supported injection type:
Type_Name Type_Value
FAULT_KMALLOC 0x000000001
+ FAULT_READ_IO 0x000000002
(no)user_xattr Setup Extended User Attributes. Note: xattr is enabled
by default if CONFIG_EROFS_FS_XATTR is selected.
(no)acl Setup POSIX Access Control List. Note: acl is enabled
diff --git a/drivers/staging/erofs/data.c b/drivers/staging/erofs/data.c
index 526e0dbea5b5..0714061ba888 100644
--- a/drivers/staging/erofs/data.c
+++ b/drivers/staging/erofs/data.c
@@ -17,11 +17,17 @@
static inline void read_endio(struct bio *bio)
{
+ struct super_block *const sb = bio->bi_private;
int i;
struct bio_vec *bvec;
- const blk_status_t err = bio->bi_status;
+ blk_status_t err = bio->bi_status;
struct bvec_iter_all iter_all;
+ if (time_to_inject(EROFS_SB(sb), FAULT_READ_IO)) {
+ erofs_show_injection_info(FAULT_READ_IO);
+ err = BLK_STS_IOERR;
+ }
+
bio_for_each_segment_all(bvec, bio, i, iter_all) {
struct page *page = bvec->bv_page;
@@ -63,7 +69,7 @@ struct page *__erofs_get_meta_page(struct super_block *sb,
if (!PageUptodate(page)) {
struct bio *bio;
- bio = erofs_grab_bio(sb, blkaddr, 1, read_endio, nofail);
+ bio = erofs_grab_bio(sb, blkaddr, 1, sb, read_endio, nofail);
if (IS_ERR(bio)) {
DBG_BUGON(nofail);
err = PTR_ERR(bio);
@@ -188,7 +194,8 @@ static inline struct bio *erofs_read_raw_page(struct bio *bio,
unsigned int nblocks,
bool ra)
{
- struct inode *inode = mapping->host;
+ struct inode *const inode = mapping->host;
+ struct super_block *const sb = inode->i_sb;
erofs_off_t current_block = (erofs_off_t)page->index;
int err;
@@ -280,9 +287,8 @@ static inline struct bio *erofs_read_raw_page(struct bio *bio,
if (nblocks > BIO_MAX_PAGES)
nblocks = BIO_MAX_PAGES;
- bio = erofs_grab_bio(inode->i_sb,
- blknr, nblocks, read_endio, false);
-
+ bio = erofs_grab_bio(sb, blknr, nblocks, sb,
+ read_endio, false);
if (IS_ERR(bio)) {
err = PTR_ERR(bio);
bio = NULL;
diff --git a/drivers/staging/erofs/internal.h b/drivers/staging/erofs/internal.h
index a66c7d495c35..c47778b3fabd 100644
--- a/drivers/staging/erofs/internal.h
+++ b/drivers/staging/erofs/internal.h
@@ -44,11 +44,12 @@
enum {
FAULT_KMALLOC,
+ FAULT_READ_IO,
FAULT_MAX,
};
#ifdef CONFIG_EROFS_FAULT_INJECTION
-extern char *erofs_fault_name[FAULT_MAX];
+extern const char *erofs_fault_name[FAULT_MAX];
#define IS_FAULT_SET(fi, type) ((fi)->inject_type & (1 << (type)))
struct erofs_fault_info {
@@ -467,7 +468,7 @@ static inline int z_erofs_map_blocks_iter(struct inode *inode,
/* data.c */
static inline struct bio *
erofs_grab_bio(struct super_block *sb,
- erofs_blk_t blkaddr, unsigned int nr_pages,
+ erofs_blk_t blkaddr, unsigned int nr_pages, void *bi_private,
bio_end_io_t endio, bool nofail)
{
const gfp_t gfp = GFP_NOIO;
@@ -489,6 +490,7 @@ erofs_grab_bio(struct super_block *sb,
bio->bi_end_io = endio;
bio_set_dev(bio, sb->s_bdev);
bio->bi_iter.bi_sector = (sector_t)blkaddr << LOG_SECTORS_PER_BLOCK;
+ bio->bi_private = bi_private;
return bio;
}
diff --git a/drivers/staging/erofs/super.c b/drivers/staging/erofs/super.c
index 7b460a3ca4d6..8bee0d3a161b 100644
--- a/drivers/staging/erofs/super.c
+++ b/drivers/staging/erofs/super.c
@@ -142,8 +142,9 @@ static int superblock_read(struct super_block *sb)
}
#ifdef CONFIG_EROFS_FAULT_INJECTION
-char *erofs_fault_name[FAULT_MAX] = {
+const char *erofs_fault_name[FAULT_MAX] = {
[FAULT_KMALLOC] = "kmalloc",
+ [FAULT_READ_IO] = "read IO error",
};
static void __erofs_build_fault_attr(struct erofs_sb_info *sbi,
diff --git a/drivers/staging/erofs/unzip_vle.c b/drivers/staging/erofs/unzip_vle.c
index 8e720bb882c7..566835cf6f2f 100644
--- a/drivers/staging/erofs/unzip_vle.c
+++ b/drivers/staging/erofs/unzip_vle.c
@@ -844,8 +844,8 @@ static void z_erofs_vle_unzip_kickoff(void *ptr, int bios)
static inline void z_erofs_vle_read_endio(struct bio *bio)
{
- const blk_status_t err = bio->bi_status;
struct erofs_sb_info *sbi = NULL;
+ blk_status_t err = bio->bi_status;
unsigned int i;
struct bio_vec *bvec;
struct bvec_iter_all iter_all;
@@ -857,9 +857,15 @@ static inline void z_erofs_vle_read_endio(struct bio *bio)
DBG_BUGON(PageUptodate(page));
DBG_BUGON(!page->mapping);
- if (unlikely(!sbi && !z_erofs_is_stagingpage(page)))
+ if (unlikely(!sbi && !z_erofs_is_stagingpage(page))) {
sbi = EROFS_SB(page->mapping->host->i_sb);
+ if (time_to_inject(sbi, FAULT_READ_IO)) {
+ erofs_show_injection_info(FAULT_READ_IO);
+ err = BLK_STS_IOERR;
+ }
+ }
+
/* sbi should already be gotten if the page is managed */
if (sbi)
cachemngd = erofs_page_is_managed(sbi, page);
@@ -1430,10 +1436,8 @@ static bool z_erofs_vle_submit_all(struct super_block *sb,
if (!bio) {
bio = erofs_grab_bio(sb, first_index + i,
- BIO_MAX_PAGES,
+ BIO_MAX_PAGES, bi_private,
z_erofs_vle_read_endio, true);
- bio->bi_private = bi_private;
-
++nr_bios;
}
--
2.12.2