From: Stefan Haberland sth@linux.ibm.com
commit 5b53a405e4658580e1faf7c217db3f55a21ba849 upstream.
For ESE devices we get an error when accessing an unformatted track. The handling of this error will return zero data for read requests and format the track on demand before writing to it. To do this the code needs to distinguish between read and write requests. This is done with data from the blocklayer request. A pointer to the blocklayer request is stored in the CQR.
If there is an error on the device an ERP request is built to do error recovery. While the ERP request is mostly a copy of the original CQR the pointer to the blocklayer request is not copied to not accidentally pass it back to the blocklayer without cleanup.
This leads to the error that during ESE handling after an ERP request was built it is not possible to determine the IO direction. This leads to the formatting of a track for read requests which might in turn lead to data corruption.
Fixes: 5e2b17e712cf ("s390/dasd: Add dynamic formatting support for ESE volumes") Cc: stable@vger.kernel.org # 5.3+ Signed-off-by: Stefan Haberland sth@linux.ibm.com Reviewed-by: Jan Hoeppner hoeppner@linux.ibm.com Link: https://lore.kernel.org/r/20220505141733.1989450-2-sth@linux.ibm.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/s390/block/dasd.c | 8 +++++++- drivers/s390/block/dasd_eckd.c | 2 +- drivers/s390/block/dasd_int.h | 12 ++++++++++++ 3 files changed, 20 insertions(+), 2 deletions(-)
--- a/drivers/s390/block/dasd.c +++ b/drivers/s390/block/dasd.c @@ -1680,6 +1680,7 @@ void dasd_int_handler(struct ccw_device unsigned long now; int nrf_suppressed = 0; int fp_suppressed = 0; + struct request *req; u8 *sense = NULL; int expires;
@@ -1780,7 +1781,12 @@ void dasd_int_handler(struct ccw_device }
if (dasd_ese_needs_format(cqr->block, irb)) { - if (rq_data_dir((struct request *)cqr->callback_data) == READ) { + req = dasd_get_callback_data(cqr); + if (!req) { + cqr->status = DASD_CQR_ERROR; + return; + } + if (rq_data_dir(req) == READ) { device->discipline->ese_read(cqr, irb); cqr->status = DASD_CQR_SUCCESS; cqr->stopclk = now; --- a/drivers/s390/block/dasd_eckd.c +++ b/drivers/s390/block/dasd_eckd.c @@ -3088,7 +3088,7 @@ dasd_eckd_ese_format(struct dasd_device sector_t curr_trk; int rc;
- req = cqr->callback_data; + req = dasd_get_callback_data(cqr); block = cqr->block; base = block->base; private = base->private; --- a/drivers/s390/block/dasd_int.h +++ b/drivers/s390/block/dasd_int.h @@ -723,6 +723,18 @@ dasd_check_blocksize(int bsize) return 0; }
+/* + * return the callback data of the original request in case there are + * ERP requests build on top of it + */ +static inline void *dasd_get_callback_data(struct dasd_ccw_req *cqr) +{ + while (cqr->refers) + cqr = cqr->refers; + + return cqr->callback_data; +} + /* externals in dasd.c */ #define DASD_PROFILE_OFF 0 #define DASD_PROFILE_ON 1