From b8e162f9e7e2da6e823a4984d6aa0523e278babf Mon Sep 17 00:00:00 2001 From: Bart Van Assche Date: Thu, 15 Apr 2021 15:08:11 -0700 Subject: scsi: core: Introduce enum scsi_disposition Improve readability of the code in the SCSI core by introducing an enumeration type for the values used internally that decide how to continue processing a SCSI command. The eh_*_handler return values have not been changed because that would involve modifying all SCSI drivers. The output of the following command has been inspected to verify that no out-of-range values are assigned to a variable of type enum scsi_disposition: KCFLAGS=-Wassign-enum make CC=clang W=1 drivers/scsi/ Link: https://lore.kernel.org/r/20210415220826.29438-6-bvanassche@acm.org Cc: Christoph Hellwig Cc: Johannes Thumshirn Cc: Hannes Reinecke Cc: Daniel Wagner Signed-off-by: Bart Van Assche Signed-off-by: Martin K. Petersen --- drivers/ata/libata-eh.c | 2 +- drivers/scsi/device_handler/scsi_dh_alua.c | 4 +- drivers/scsi/device_handler/scsi_dh_emc.c | 4 +- drivers/scsi/device_handler/scsi_dh_rdac.c | 4 +- drivers/scsi/scsi_error.c | 64 ++++++++++++++++-------------- drivers/scsi/scsi_lib.c | 2 +- drivers/scsi/scsi_priv.h | 2 +- include/scsi/scsi.h | 21 +++++----- include/scsi/scsi_dh.h | 3 +- include/scsi/scsi_eh.h | 2 +- 10 files changed, 57 insertions(+), 51 deletions(-) diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c index b6f92050e60c..5352be2b447d 100644 --- a/drivers/ata/libata-eh.c +++ b/drivers/ata/libata-eh.c @@ -1599,7 +1599,7 @@ static unsigned int ata_eh_analyze_tf(struct ata_queued_cmd *qc, } if (qc->flags & ATA_QCFLAG_SENSE_VALID) { - int ret = scsi_check_sense(qc->scsicmd); + enum scsi_disposition ret = scsi_check_sense(qc->scsicmd); /* * SUCCESS here means that the sense code could be * evaluated and should be passed to the upper layers diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index e6fde27d4565..efa8c0381476 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -405,8 +405,8 @@ static char print_alua_state(unsigned char state) } } -static int alua_check_sense(struct scsi_device *sdev, - struct scsi_sense_hdr *sense_hdr) +static enum scsi_disposition alua_check_sense(struct scsi_device *sdev, + struct scsi_sense_hdr *sense_hdr) { struct alua_dh_data *h = sdev->handler_data; struct alua_port_group *pg; diff --git a/drivers/scsi/device_handler/scsi_dh_emc.c b/drivers/scsi/device_handler/scsi_dh_emc.c index caa685cfe3d4..bd28ec6cfb72 100644 --- a/drivers/scsi/device_handler/scsi_dh_emc.c +++ b/drivers/scsi/device_handler/scsi_dh_emc.c @@ -280,8 +280,8 @@ static int send_trespass_cmd(struct scsi_device *sdev, return res; } -static int clariion_check_sense(struct scsi_device *sdev, - struct scsi_sense_hdr *sense_hdr) +static enum scsi_disposition clariion_check_sense(struct scsi_device *sdev, + struct scsi_sense_hdr *sense_hdr) { switch (sense_hdr->sense_key) { case NOT_READY: diff --git a/drivers/scsi/device_handler/scsi_dh_rdac.c b/drivers/scsi/device_handler/scsi_dh_rdac.c index 5efc959493ec..25f6e1ac9e7b 100644 --- a/drivers/scsi/device_handler/scsi_dh_rdac.c +++ b/drivers/scsi/device_handler/scsi_dh_rdac.c @@ -656,8 +656,8 @@ static blk_status_t rdac_prep_fn(struct scsi_device *sdev, struct request *req) return BLK_STS_OK; } -static int rdac_check_sense(struct scsi_device *sdev, - struct scsi_sense_hdr *sense_hdr) +static enum scsi_disposition rdac_check_sense(struct scsi_device *sdev, + struct scsi_sense_hdr *sense_hdr) { struct rdac_dh_data *h = sdev->handler_data; diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c index 271718e888d1..d8fafe77dbbe 100644 --- a/drivers/scsi/scsi_error.c +++ b/drivers/scsi/scsi_error.c @@ -60,8 +60,8 @@ static void scsi_eh_done(struct scsi_cmnd *scmd); #define HOST_RESET_SETTLE_TIME (10) static int scsi_eh_try_stu(struct scsi_cmnd *scmd); -static int scsi_try_to_abort_cmd(struct scsi_host_template *, - struct scsi_cmnd *); +static enum scsi_disposition scsi_try_to_abort_cmd(struct scsi_host_template *, + struct scsi_cmnd *); void scsi_eh_wakeup(struct Scsi_Host *shost) { @@ -151,7 +151,7 @@ scmd_eh_abort_handler(struct work_struct *work) struct scsi_cmnd *scmd = container_of(work, struct scsi_cmnd, abort_work.work); struct scsi_device *sdev = scmd->device; - int rtn; + enum scsi_disposition rtn; if (scsi_host_eh_past_deadline(sdev->host)) { SCSI_LOG_ERROR_RECOVERY(3, @@ -498,7 +498,7 @@ static void scsi_report_sense(struct scsi_device *sdev, * When a deferred error is detected the current command has * not been executed and needs retrying. */ -int scsi_check_sense(struct scsi_cmnd *scmd) +enum scsi_disposition scsi_check_sense(struct scsi_cmnd *scmd) { struct scsi_device *sdev = scmd->device; struct scsi_sense_hdr sshdr; @@ -512,7 +512,7 @@ int scsi_check_sense(struct scsi_cmnd *scmd) return NEEDS_RETRY; if (sdev->handler && sdev->handler->check_sense) { - int rc; + enum scsi_disposition rc; rc = sdev->handler->check_sense(sdev, &sshdr); if (rc != SCSI_RETURN_NOT_HANDLED) @@ -723,7 +723,7 @@ static void scsi_handle_queue_full(struct scsi_device *sdev) * don't allow for the possibility of retries here, and we are a lot * more restrictive about what we consider acceptable. */ -static int scsi_eh_completed_normally(struct scsi_cmnd *scmd) +static enum scsi_disposition scsi_eh_completed_normally(struct scsi_cmnd *scmd) { /* * first check the host byte, to see if there is anything in there @@ -804,10 +804,10 @@ static void scsi_eh_done(struct scsi_cmnd *scmd) * scsi_try_host_reset - ask host adapter to reset itself * @scmd: SCSI cmd to send host reset. */ -static int scsi_try_host_reset(struct scsi_cmnd *scmd) +static enum scsi_disposition scsi_try_host_reset(struct scsi_cmnd *scmd) { unsigned long flags; - int rtn; + enum scsi_disposition rtn; struct Scsi_Host *host = scmd->device->host; struct scsi_host_template *hostt = host->hostt; @@ -834,10 +834,10 @@ static int scsi_try_host_reset(struct scsi_cmnd *scmd) * scsi_try_bus_reset - ask host to perform a bus reset * @scmd: SCSI cmd to send bus reset. */ -static int scsi_try_bus_reset(struct scsi_cmnd *scmd) +static enum scsi_disposition scsi_try_bus_reset(struct scsi_cmnd *scmd) { unsigned long flags; - int rtn; + enum scsi_disposition rtn; struct Scsi_Host *host = scmd->device->host; struct scsi_host_template *hostt = host->hostt; @@ -876,10 +876,10 @@ static void __scsi_report_device_reset(struct scsi_device *sdev, void *data) * timer on it, and set the host back to a consistent state prior to * returning. */ -static int scsi_try_target_reset(struct scsi_cmnd *scmd) +static enum scsi_disposition scsi_try_target_reset(struct scsi_cmnd *scmd) { unsigned long flags; - int rtn; + enum scsi_disposition rtn; struct Scsi_Host *host = scmd->device->host; struct scsi_host_template *hostt = host->hostt; @@ -907,9 +907,9 @@ static int scsi_try_target_reset(struct scsi_cmnd *scmd) * timer on it, and set the host back to a consistent state prior to * returning. */ -static int scsi_try_bus_device_reset(struct scsi_cmnd *scmd) +static enum scsi_disposition scsi_try_bus_device_reset(struct scsi_cmnd *scmd) { - int rtn; + enum scsi_disposition rtn; struct scsi_host_template *hostt = scmd->device->host->hostt; if (!hostt->eh_device_reset_handler) @@ -938,8 +938,8 @@ static int scsi_try_bus_device_reset(struct scsi_cmnd *scmd) * if the device is temporarily unavailable (eg due to a * link down on FibreChannel) */ -static int scsi_try_to_abort_cmd(struct scsi_host_template *hostt, - struct scsi_cmnd *scmd) +static enum scsi_disposition +scsi_try_to_abort_cmd(struct scsi_host_template *hostt, struct scsi_cmnd *scmd) { if (!hostt->eh_abort_handler) return FAILED; @@ -1072,8 +1072,8 @@ EXPORT_SYMBOL(scsi_eh_restore_cmnd); * Return value: * SUCCESS or FAILED or NEEDS_RETRY */ -static int scsi_send_eh_cmnd(struct scsi_cmnd *scmd, unsigned char *cmnd, - int cmnd_size, int timeout, unsigned sense_bytes) +static enum scsi_disposition scsi_send_eh_cmnd(struct scsi_cmnd *scmd, + unsigned char *cmnd, int cmnd_size, int timeout, unsigned sense_bytes) { struct scsi_device *sdev = scmd->device; struct Scsi_Host *shost = sdev->host; @@ -1180,12 +1180,13 @@ retry: * that we obtain it on our own. This function will *not* return until * the command either times out, or it completes. */ -static int scsi_request_sense(struct scsi_cmnd *scmd) +static enum scsi_disposition scsi_request_sense(struct scsi_cmnd *scmd) { return scsi_send_eh_cmnd(scmd, NULL, 0, scmd->device->eh_timeout, ~0); } -static int scsi_eh_action(struct scsi_cmnd *scmd, int rtn) +static enum scsi_disposition +scsi_eh_action(struct scsi_cmnd *scmd, enum scsi_disposition rtn) { if (!blk_rq_is_passthrough(scmd->request)) { struct scsi_driver *sdrv = scsi_cmd_to_driver(scmd); @@ -1238,7 +1239,7 @@ int scsi_eh_get_sense(struct list_head *work_q, { struct scsi_cmnd *scmd, *next; struct Scsi_Host *shost; - int rtn; + enum scsi_disposition rtn; /* * If SCSI_EH_ABORT_SCHEDULED has been set, it is timeout IO, @@ -1316,7 +1317,8 @@ EXPORT_SYMBOL_GPL(scsi_eh_get_sense); static int scsi_eh_tur(struct scsi_cmnd *scmd) { static unsigned char tur_command[6] = {TEST_UNIT_READY, 0, 0, 0, 0, 0}; - int retry_cnt = 1, rtn; + int retry_cnt = 1; + enum scsi_disposition rtn; retry_tur: rtn = scsi_send_eh_cmnd(scmd, tur_command, 6, @@ -1404,7 +1406,8 @@ static int scsi_eh_try_stu(struct scsi_cmnd *scmd) static unsigned char stu_command[6] = {START_STOP, 0, 0, 0, 1, 0}; if (scmd->device->allow_restart) { - int i, rtn = NEEDS_RETRY; + int i; + enum scsi_disposition rtn = NEEDS_RETRY; for (i = 0; rtn == NEEDS_RETRY && i < 2; i++) rtn = scsi_send_eh_cmnd(scmd, stu_command, 6, scmd->device->request_queue->rq_timeout, 0); @@ -1498,7 +1501,7 @@ static int scsi_eh_bus_device_reset(struct Scsi_Host *shost, { struct scsi_cmnd *scmd, *bdr_scmd, *next; struct scsi_device *sdev; - int rtn; + enum scsi_disposition rtn; shost_for_each_device(sdev, shost) { if (scsi_host_eh_past_deadline(shost)) { @@ -1565,7 +1568,7 @@ static int scsi_eh_target_reset(struct Scsi_Host *shost, while (!list_empty(&tmp_list)) { struct scsi_cmnd *next, *scmd; - int rtn; + enum scsi_disposition rtn; unsigned int id; if (scsi_host_eh_past_deadline(shost)) { @@ -1623,7 +1626,7 @@ static int scsi_eh_bus_reset(struct Scsi_Host *shost, struct scsi_cmnd *scmd, *chan_scmd, *next; LIST_HEAD(check_list); unsigned int channel; - int rtn; + enum scsi_disposition rtn; /* * we really want to loop over the various channels, and do this on @@ -1694,7 +1697,7 @@ static int scsi_eh_host_reset(struct Scsi_Host *shost, { struct scsi_cmnd *scmd, *next; LIST_HEAD(check_list); - int rtn; + enum scsi_disposition rtn; if (!list_empty(work_q)) { scmd = list_entry(work_q->next, @@ -1800,9 +1803,9 @@ check_type: * doesn't require the error handler read (i.e. we don't need to * abort/reset), this function should return SUCCESS. */ -int scsi_decide_disposition(struct scsi_cmnd *scmd) +enum scsi_disposition scsi_decide_disposition(struct scsi_cmnd *scmd) { - int rtn; + enum scsi_disposition rtn; /* * if the device is offline, then we clearly just pass the result back @@ -2365,7 +2368,8 @@ scsi_ioctl_reset(struct scsi_device *dev, int __user *arg) struct Scsi_Host *shost = dev->host; struct request *rq; unsigned long flags; - int error = 0, rtn, val; + int error = 0, val; + enum scsi_disposition rtn; if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RAWIO)) return -EACCES; diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c index 8ffb789de6f7..d7c0d5a5f263 100644 --- a/drivers/scsi/scsi_lib.c +++ b/drivers/scsi/scsi_lib.c @@ -1441,7 +1441,7 @@ static bool scsi_mq_lld_busy(struct request_queue *q) static void scsi_complete(struct request *rq) { struct scsi_cmnd *cmd = blk_mq_rq_to_pdu(rq); - int disposition; + enum scsi_disposition disposition; INIT_LIST_HEAD(&cmd->eh_entry); diff --git a/drivers/scsi/scsi_priv.h b/drivers/scsi/scsi_priv.h index ed240f006c04..75d6f23e4fff 100644 --- a/drivers/scsi/scsi_priv.h +++ b/drivers/scsi/scsi_priv.h @@ -74,7 +74,7 @@ extern void scsi_exit_devinfo(void); extern void scmd_eh_abort_handler(struct work_struct *work); extern enum blk_eh_timer_return scsi_times_out(struct request *req); extern int scsi_error_handler(void *host); -extern int scsi_decide_disposition(struct scsi_cmnd *cmd); +extern enum scsi_disposition scsi_decide_disposition(struct scsi_cmnd *cmd); extern void scsi_eh_wakeup(struct Scsi_Host *shost); extern void scsi_eh_scmd_add(struct scsi_cmnd *); void scsi_eh_ready_devs(struct Scsi_Host *shost, diff --git a/include/scsi/scsi.h b/include/scsi/scsi.h index e75cca25338a..246ced401683 100644 --- a/include/scsi/scsi.h +++ b/include/scsi/scsi.h @@ -180,16 +180,17 @@ static inline int scsi_is_wlun(u64 lun) /* * Internal return values. */ - -#define NEEDS_RETRY 0x2001 -#define SUCCESS 0x2002 -#define FAILED 0x2003 -#define QUEUED 0x2004 -#define SOFT_ERROR 0x2005 -#define ADD_TO_MLQUEUE 0x2006 -#define TIMEOUT_ERROR 0x2007 -#define SCSI_RETURN_NOT_HANDLED 0x2008 -#define FAST_IO_FAIL 0x2009 +enum scsi_disposition { + NEEDS_RETRY = 0x2001, + SUCCESS = 0x2002, + FAILED = 0x2003, + QUEUED = 0x2004, + SOFT_ERROR = 0x2005, + ADD_TO_MLQUEUE = 0x2006, + TIMEOUT_ERROR = 0x2007, + SCSI_RETURN_NOT_HANDLED = 0x2008, + FAST_IO_FAIL = 0x2009, +}; /* * Midlevel queue return values. diff --git a/include/scsi/scsi_dh.h b/include/scsi/scsi_dh.h index a9f782fe732a..4df943c1b90b 100644 --- a/include/scsi/scsi_dh.h +++ b/include/scsi/scsi_dh.h @@ -52,7 +52,8 @@ struct scsi_device_handler { /* Filled by the hardware handler */ struct module *module; const char *name; - int (*check_sense)(struct scsi_device *, struct scsi_sense_hdr *); + enum scsi_disposition (*check_sense)(struct scsi_device *, + struct scsi_sense_hdr *); int (*attach)(struct scsi_device *); void (*detach)(struct scsi_device *); int (*activate)(struct scsi_device *, activate_complete, void *); diff --git a/include/scsi/scsi_eh.h b/include/scsi/scsi_eh.h index 6bd5ed695a5e..468094254b3c 100644 --- a/include/scsi/scsi_eh.h +++ b/include/scsi/scsi_eh.h @@ -17,7 +17,7 @@ extern void scsi_report_device_reset(struct Scsi_Host *, int, int); extern int scsi_block_when_processing_errors(struct scsi_device *); extern bool scsi_command_normalize_sense(const struct scsi_cmnd *cmd, struct scsi_sense_hdr *sshdr); -extern int scsi_check_sense(struct scsi_cmnd *); +extern enum scsi_disposition scsi_check_sense(struct scsi_cmnd *); static inline bool scsi_sense_is_deferred(const struct scsi_sense_hdr *sshdr) { -- cgit v1.2.3