Teach zpool scrub to scrub only blocks in error log

Added a flag '-e' in zpool scrub to scrub only blocks in error log. A
user can pause, resume and cancel the error scrub by passing additional
command line arguments -p -s just like a regular scrub. This involves
adding a new flag, creating new libzfs interfaces, a new ioctl, and the
actual iteration and read-issuing logic. Error scrubbing is executed in
multiple txg to make sure pool performance is not affected.

Reviewed-by: Brian Behlendorf <[email protected]>
Reviewed-by: Tony Hutter <[email protected]>
Co-authored-by: TulsiJain [email protected]
Signed-off-by: George Amanakis <[email protected]>
Closes #8995
Closes #12355

1 files changed, 18 insertions, 1 deletions

diff --git a/include/sys/fs/zfs.h b/include/sys/fs/zfs.h
index 4c2097fb8..93193fa14 100644
--- a/include/sys/fs/zfs.h
+++ b/include/sys/fs/zfs.h
@@ -1036,6 +1036,7 @@ typedef enum pool_scan_func {
 	POOL_SCAN_NONE,
 	POOL_SCAN_SCRUB,
 	POOL_SCAN_RESILVER,
+	POOL_SCAN_ERRORSCRUB,
 	POOL_SCAN_FUNCS
 } pool_scan_func_t;
 
@@ -1099,6 +1100,20 @@ typedef struct pool_scan_stat {
 	uint64_t	pss_pass_scrub_spent_paused;
 	uint64_t	pss_pass_issued; /* issued bytes per scan pass */
 	uint64_t	pss_issued;	/* total bytes checked by scanner */
+
+	/* error scrub values stored on disk */
+	uint64_t	pss_error_scrub_func;	/* pool_scan_func_t */
+	uint64_t	pss_error_scrub_state;	/* dsl_scan_state_t */
+	uint64_t	pss_error_scrub_start;	/* error scrub start time */
+	uint64_t	pss_error_scrub_end;	/* error scrub end time */
+	uint64_t	pss_error_scrub_examined; /* error blocks issued I/O */
+	/* error blocks to be issued I/O */
+	uint64_t	pss_error_scrub_to_be_examined;
+
+	/* error scrub values not stored on disk */
+	/* error scrub pause time in milliseconds */
+	uint64_t	pss_pass_error_scrub_pause;
+
 } pool_scan_stat_t;
 
 typedef struct pool_removal_stat {
@@ -1120,6 +1135,7 @@ typedef enum dsl_scan_state {
 	DSS_SCANNING,
 	DSS_FINISHED,
 	DSS_CANCELED,
+	DSS_ERRORSCRUBBING,
 	DSS_NUM_STATES
 } dsl_scan_state_t;
 
@@ -1360,7 +1376,7 @@ typedef enum {
  */
 typedef enum zfs_ioc {
 	/*
-	 * Core features - 81/128 numbers reserved.
+	 * Core features - 88/128 numbers reserved.
 	 */
 #ifdef __FreeBSD__
 	ZFS_IOC_FIRST =	0,
@@ -1455,6 +1471,7 @@ typedef enum zfs_ioc {
 	ZFS_IOC_WAIT_FS,			/* 0x5a54 */
 	ZFS_IOC_VDEV_GET_PROPS,			/* 0x5a55 */
 	ZFS_IOC_VDEV_SET_PROPS,			/* 0x5a56 */
+	ZFS_IOC_POOL_SCRUB,			/* 0x5a57 */
 
 	/*
 	 * Per-platform (Optional) - 8/128 numbers reserved.