From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BACD4C433ED for ; Fri, 7 May 2021 00:04:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 8AF17601FD for ; Fri, 7 May 2021 00:04:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233434AbhEGAFX (ORCPT ); Thu, 6 May 2021 20:05:23 -0400 Received: from m43-7.mailgun.net ([69.72.43.7]:12850 "EHLO m43-7.mailgun.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232375AbhEGAFV (ORCPT ); Thu, 6 May 2021 20:05:21 -0400 DKIM-Signature: a=rsa-sha256; v=1; c=relaxed/relaxed; d=mg.codeaurora.org; q=dns/txt; s=smtp; t=1620345862; h=Message-ID: References: In-Reply-To: Subject: Cc: To: From: Date: Content-Transfer-Encoding: Content-Type: MIME-Version: Sender; bh=2xMuumYUl/aC0jx55vxufWFADJvMcF734oszdBtT4UM=; b=t3TEky8+BdOpo2obv3lYqawiWTVQnJ3XVRjGs/N3fMZhysRZYBVLdzCcGhh3l3m9H+dF4YsL fsvVsLF4BOaaPtpWiCdi2C6LVSEfpahSMjPfYdzrhkl0mgjjN3OwZ5knGWtyIukAk5I4wTqP ZZVof8DgeWuCewcey7vFIYnxUuE= X-Mailgun-Sending-Ip: 69.72.43.7 X-Mailgun-Sid: WyJlNmU5NiIsICJsaW51eC1zY3NpQHZnZXIua2VybmVsLm9yZyIsICJiZTllNGEiXQ== Received: from smtp.codeaurora.org (ec2-35-166-182-171.us-west-2.compute.amazonaws.com [35.166.182.171]) by smtp-out-n06.prod.us-west-2.postgun.com with SMTP id 609483f6e0e9c9a6b6bf5233 (version=TLS1.2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256); Fri, 07 May 2021 00:04:06 GMT Sender: cang=codeaurora.org@mg.codeaurora.org Received: by smtp.codeaurora.org (Postfix, from userid 1001) id D0306C43149; Fri, 7 May 2021 00:04:06 +0000 (UTC) Received: from mail.codeaurora.org (localhost.localdomain [127.0.0.1]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) (Authenticated sender: cang) by smtp.codeaurora.org (Postfix) with ESMTPSA id 787EFC433D3; Fri, 7 May 2021 00:04:04 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Fri, 07 May 2021 08:04:04 +0800 From: Can Guo To: Bart Van Assche Cc: "Martin K . Petersen" , "James E . J . Bottomley" , linux-scsi@vger.kernel.org, Christoph Hellwig , Ming Lei , Hannes Reinecke , John Garry , James Smart , Lee Duncan Subject: Re: [PATCH 011/117] Introduce the scsi_status union In-Reply-To: <20210420000845.25873-12-bvanassche@acm.org> References: <20210420000845.25873-1-bvanassche@acm.org> <20210420000845.25873-12-bvanassche@acm.org> Message-ID: <21012e074db33f317005e09f5a3a18a3@codeaurora.org> X-Sender: cang@codeaurora.org User-Agent: Roundcube Webmail/1.3.9 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org On 2021-04-20 08:06, Bart Van Assche wrote: > Introduce the scsi_status union, a data structure that will be used in > the > next patches to replace SCSI status codes represented as an integer. > Define > that data structure as follows: > > union scsi_status { > int32_t combined; > struct { > #if defined(__BIG_ENDIAN) > enum driver_status driver; > enum host_status host; > enum msg_byte msg; > enum sam_status status; > #elif defined(__LITTLE_ENDIAN) > enum sam_status status; > enum msg_byte msg; > enum host_status host; > enum driver_status driver; > #else > #error Endianness? > #endif > } b; > }; > > The 'combined' member makes it easy to convert existing SCSI code. The > 'status', 'msg', 'host' and 'driver' enable access of individual SCSI > status fields in a type-safe fashion. > > Change 'int result;' into the following to enable converting one driver > at > a time: > > union { > int result; > union scsi_status status; > }; > > A later patch will remove the outer union and 'int result;'. > > Also to enable converting one driver at a time, make > scsi_status_is_good(), > status_byte(), msg_byte(), host_byte() and driver_byte() accept an int > or > union scsi_status as argument. A later patch will make this function > and > these macros accept the scsi_status union only. > > Cc: Christoph Hellwig > Cc: Ming Lei > Cc: Hannes Reinecke > Cc: John Garry > Cc: Can Guo > Cc: James Smart > Cc: Lee Duncan > Signed-off-by: Bart Van Assche > --- > drivers/scsi/scsi.c | 9 +++++++++ > include/linux/bsg-lib.h | 6 +++++- > include/scsi/scsi.h | 24 +++++++++++++++++++----- > include/scsi/scsi_bsg_iscsi.h | 6 +++++- > include/scsi/scsi_cmnd.h | 14 +++++++++----- > include/scsi/scsi_eh.h | 7 ++++++- > include/scsi/scsi_request.h | 6 +++++- > include/scsi/scsi_status.h | 29 +++++++++++++++++++++++++++++ > include/uapi/scsi/scsi_bsg_fc.h | 10 ++++++++++ > include/uapi/scsi/scsi_bsg_ufs.h | 11 +++++++++++ > 10 files changed, 108 insertions(+), 14 deletions(-) > > diff --git a/drivers/scsi/scsi.c b/drivers/scsi/scsi.c > index e9e2f0e15ac8..4f71f2005be4 100644 > --- a/drivers/scsi/scsi.c > +++ b/drivers/scsi/scsi.c > @@ -763,10 +763,19 @@ MODULE_LICENSE("GPL"); > module_param(scsi_logging_level, int, S_IRUGO|S_IWUSR); > MODULE_PARM_DESC(scsi_logging_level, "a bit mask of logging levels"); > > +#define TEST_STATUS ((union scsi_status){.combined = 0x01020308}) > + > static int __init init_scsi(void) > { > int error; > > + BUILD_BUG_ON(sizeof(union scsi_status) != 4); > + BUILD_BUG_ON(TEST_STATUS.combined != 0x01020308); > + BUILD_BUG_ON(driver_byte(TEST_STATUS) != 1); > + BUILD_BUG_ON(host_byte(TEST_STATUS) != 2); > + BUILD_BUG_ON(msg_byte(TEST_STATUS) != 3); > + BUILD_BUG_ON(status_byte(TEST_STATUS) != 4); > + > error = scsi_init_procfs(); > if (error) > goto cleanup_queue; > diff --git a/include/linux/bsg-lib.h b/include/linux/bsg-lib.h > index 960988d42f77..f934afc45760 100644 > --- a/include/linux/bsg-lib.h > +++ b/include/linux/bsg-lib.h > @@ -11,6 +11,7 @@ > > #include > #include > +#include > > struct request; > struct device; > @@ -52,7 +53,10 @@ struct bsg_job { > struct bsg_buffer request_payload; > struct bsg_buffer reply_payload; > > - int result; > + union { > + int result; /* do not use in new code */ > + union scsi_status status; > + }; > unsigned int reply_payload_rcv_len; > > /* BIDI support */ > diff --git a/include/scsi/scsi.h b/include/scsi/scsi.h > index c9ccb6b45b76..18bb1fb2458f 100644 > --- a/include/scsi/scsi.h > +++ b/include/scsi/scsi.h > @@ -39,7 +39,7 @@ enum scsi_timeouts { > * This returns true for known good conditions that may be treated as > * command completed normally > */ > -static inline int scsi_status_is_good(int status) > +static inline bool __scsi_status_is_good(int status) > { > /* > * FIXME: bit0 is listed as reserved in SCSI-2, but is > @@ -56,6 +56,20 @@ static inline int scsi_status_is_good(int status) > (status == SAM_STAT_COMMAND_TERMINATED)); > } > > +/* > + * If the 'status' argument has type int, unsigned int or union > scsi_status, > + * return the combined SCSI status. If the 'status' argument has > another type, > + * trigger a compiler error by passing a struct to a context where an > integer > + * is expected. > + */ > +#define scsi_status_to_int(status) \ > + __builtin_choose_expr(sizeof(status) == 4, \ > + *(int32_t *)&(status), \ > + (union scsi_status){}) > + > +#define scsi_status_is_good(status) \ > + __scsi_status_is_good(scsi_status_to_int(status)) > + > > /* > * standard mode-select header prepended to all mode-select commands > @@ -134,10 +148,10 @@ enum scsi_disposition { > * driver_byte = set by mid-level. > */ > #define status_byte(result) ((enum sam_status_divided_by_two) \ > - (((result) >> 1) & 0x7f)) > -#define msg_byte(result) (((result) >> 8) & 0xff) > -#define host_byte(result) (((result) >> 16) & 0xff) > -#define driver_byte(result) (((result) >> 24) & 0xff) > + ((scsi_status_to_int((result)) >> 1) & 0x7f)) > +#define msg_byte(result) ((scsi_status_to_int((result)) >> 8) & > 0xff) > +#define host_byte(result) ((scsi_status_to_int((result)) >> 16) & > 0xff) > +#define driver_byte(result) ((scsi_status_to_int((result)) >> 24) & > 0xff) > > #define sense_class(sense) (((sense) >> 4) & 0x7) > #define sense_error(sense) ((sense) & 0xf) > diff --git a/include/scsi/scsi_bsg_iscsi.h > b/include/scsi/scsi_bsg_iscsi.h > index 6b8128005af8..d18e7e061927 100644 > --- a/include/scsi/scsi_bsg_iscsi.h > +++ b/include/scsi/scsi_bsg_iscsi.h > @@ -13,6 +13,7 @@ > */ > > #include > +#include > > /* > * iSCSI Transport SGIO v4 BSG Message Support > @@ -82,7 +83,10 @@ struct iscsi_bsg_reply { > * msg and status fields. The per-msgcode reply structure > * will contain valid data. > */ > - uint32_t result; > + union { > + uint32_t result; /* do not use in new code */ > + union scsi_status status; > + }; > > /* If there was reply_payload, how much was recevied ? */ > uint32_t reply_payload_rcv_len; > diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h > index 202106e7c814..539be97b0a7d 100644 > --- a/include/scsi/scsi_cmnd.h > +++ b/include/scsi/scsi_cmnd.h > @@ -140,7 +140,11 @@ struct scsi_cmnd { > * obtained by scsi_malloc is guaranteed > * to be at an address < 16Mb). */ > > - int result; /* Status code from lower level driver */ > + /* Status code from lower level driver */ > + union { > + int result; /* do not use in new code. */ > + union scsi_status status; > + }; > int flags; /* Command flags */ > unsigned long state; /* Command completion state */ > > @@ -317,23 +321,23 @@ static inline struct scsi_data_buffer > *scsi_prot(struct scsi_cmnd *cmd) > static inline void set_status_byte(struct scsi_cmnd *cmd, > enum sam_status status) > { > - cmd->result = (cmd->result & 0xffffff00) | status; > + cmd->status.b.status = status; > } > > static inline void set_msg_byte(struct scsi_cmnd *cmd, enum msg_byte > status) > { > - cmd->result = (cmd->result & 0xffff00ff) | (status << 8); > + cmd->status.b.msg = status; > } > > static inline void set_host_byte(struct scsi_cmnd *cmd, enum > host_status status) > { > - cmd->result = (cmd->result & 0xff00ffff) | (status << 16); > + cmd->status.b.host = status; > } > > static inline void set_driver_byte(struct scsi_cmnd *cmd, > enum driver_status status) > { > - cmd->result = (cmd->result & 0x00ffffff) | (status << 24); > + cmd->status.b.driver = status; > } > > static inline unsigned scsi_transfer_length(struct scsi_cmnd *scmd) > diff --git a/include/scsi/scsi_eh.h b/include/scsi/scsi_eh.h > index 468094254b3c..dcd66bb9a1ba 100644 > --- a/include/scsi/scsi_eh.h > +++ b/include/scsi/scsi_eh.h > @@ -6,6 +6,8 @@ > > #include > #include > +#include > + > struct scsi_device; > struct Scsi_Host; > > @@ -31,7 +33,10 @@ extern int scsi_ioctl_reset(struct scsi_device *, > int __user *); > > struct scsi_eh_save { > /* saved state */ > - int result; > + union { > + int result; /* do not use in new code */ > + union scsi_status status; > + }; > unsigned int resid_len; > int eh_eflags; > enum dma_data_direction data_direction; > diff --git a/include/scsi/scsi_request.h b/include/scsi/scsi_request.h > index b06f28c74908..83f5549cc74c 100644 > --- a/include/scsi/scsi_request.h > +++ b/include/scsi/scsi_request.h > @@ -3,6 +3,7 @@ > #define _SCSI_SCSI_REQUEST_H > > #include > +#include > > #define BLK_MAX_CDB 16 > > @@ -10,7 +11,10 @@ struct scsi_request { > unsigned char __cmd[BLK_MAX_CDB]; > unsigned char *cmd; > unsigned short cmd_len; > - int result; > + union { > + int result; /* do not use in new code */ > + union scsi_status status; > + }; > unsigned int sense_len; > unsigned int resid_len; /* residual count */ > int retries; > diff --git a/include/scsi/scsi_status.h b/include/scsi/scsi_status.h > index da2ba825f981..120f5a43d2ed 100644 > --- a/include/scsi/scsi_status.h > +++ b/include/scsi/scsi_status.h > @@ -3,6 +3,7 @@ > > #include > #include > +#include > #include > > /* > @@ -88,4 +89,32 @@ enum driver_status { > DRIVER_SENSE = 0x08, > } __packed; > > +/** > + * SCSI status passed by LLDs to the midlayer. > + * @combined: One of the following: > + * - A (driver, host, msg, status) quadruplet encoded as a 32-bit > integer. > + * - A negative Unix error code. > + * - In the IDE code, a positive value that represents an error code, > an > + * error counter or a bitfield. > + * @b: SCSI status code. > + */ > +union scsi_status { > + int32_t combined; > + struct { > +#if defined(__BIG_ENDIAN) > + enum driver_status driver; > + enum host_status host; > + enum msg_byte msg; > + enum sam_status status; > +#elif defined(__LITTLE_ENDIAN) > + enum sam_status status; > + enum msg_byte msg; > + enum host_status host; > + enum driver_status driver; > +#else > +#error Endianness? > +#endif > + } b; > +}; > + > #endif /* _SCSI_SCSI_STATUS_H */ > diff --git a/include/uapi/scsi/scsi_bsg_fc.h > b/include/uapi/scsi/scsi_bsg_fc.h > index 3ae65e93235c..419db719fe8e 100644 > --- a/include/uapi/scsi/scsi_bsg_fc.h > +++ b/include/uapi/scsi/scsi_bsg_fc.h > @@ -9,6 +9,9 @@ > #define SCSI_BSG_FC_H > > #include > +#ifdef __KERNEL__ > +#include > +#endif > > /* > * This file intended to be included by both kernel and user space > @@ -291,7 +294,14 @@ struct fc_bsg_reply { > * msg and status fields. The per-msgcode reply structure > * will contain valid data. > */ > +#ifdef __KERNEL__ > + union { > + __u32 result; /* do not use in new kernel code */ > + union scsi_status status; > + }; > +#else > __u32 result; > +#endif > > /* If there was reply_payload, how much was recevied ? */ > __u32 reply_payload_rcv_len; > diff --git a/include/uapi/scsi/scsi_bsg_ufs.h > b/include/uapi/scsi/scsi_bsg_ufs.h > index d55f2176dfd4..3dfe5a5a0842 100644 > --- a/include/uapi/scsi/scsi_bsg_ufs.h > +++ b/include/uapi/scsi/scsi_bsg_ufs.h > @@ -9,6 +9,10 @@ > #define SCSI_BSG_UFS_H > > #include > +#ifdef __KERNEL__ > +#include > +#endif > + > /* > * This file intended to be included by both kernel and user space > */ > @@ -95,7 +99,14 @@ struct ufs_bsg_reply { > * msg and status fields. The per-msgcode reply structure > * will contain valid data. > */ > +#ifdef __KERNEL__ > + union { > + __u32 result; /* do not use in new kernel code */ > + union scsi_status status; > + }; > +#else > __u32 result; > +#endif > > /* If there was reply_payload, how much was received? */ > __u32 reply_payload_rcv_len; Reviewed-by: Can Guo