From mboxrd@z Thu Jan 1 00:00:00 1970 From: Paul Bolle Subject: [PATCH v2] target_core_alua: silence GCC warning Date: Thu, 20 Feb 2014 09:07:52 +0100 Message-ID: <1392883672.5070.21.camel@x220> References: <1392714172-2712-1-git-send-email-geert@linux-m68k.org> <1392803546.27558.16.camel@x220> <1392804347.27558.20.camel@x220> <1392850749.22195.1.camel@haakon3.risingtidesystems.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: In-Reply-To: <1392850749.22195.1.camel@haakon3.risingtidesystems.com> Sender: target-devel-owner@vger.kernel.org To: "Nicholas A. Bellinger" Cc: Geert Uytterhoeven , linux-scsi@vger.kernel.org, target-devel@vger.kernel.org, linux-kernel@vger.kernel.org List-Id: linux-scsi@vger.kernel.org Building target_core_alua.o triggers a GCC warning: drivers/target/target_core_alua.c: In function =E2=80=98target_alua= _state_check=E2=80=99: drivers/target/target_core_alua.c:773:18: warning: =E2=80=98alua_as= cq=E2=80=99 may be used uninitialized in this function [-Wmaybe-uniniti= alized] cmd->scsi_ascq =3D alua_ascq; ^ This is a false positive. A little trial and error shows it is apparently caused by core_alua_state_lba_dependent(). It must be hard for GCC to track the branches of a switch statement, inside a list_for_each_entry loop, inside a while loop. But if we add a small (inline) helper function we can reorganize the code a bit. That also allows to drop alua_ascq which, obviously, gets rid of this warning. Signed-off-by: Paul Bolle --- v2: Make core_alua_state_nonoptimized() return void, as Geert suggested.=20 Also keep core_alua_state_lba_dependent() inline. Setting that function noinline was just a leftover from the trial and error fase, and isn't needed to make the warning go away. Ie, I was sloppy in v1! Still compile tested only. drivers/target/target_core_alua.c | 95 ++++++++++++++++++-------------= -------- 1 file changed, 44 insertions(+), 51 deletions(-) diff --git a/drivers/target/target_core_alua.c b/drivers/target/target_= core_alua.c index c3d9df6..fcbe612 100644 --- a/drivers/target/target_core_alua.c +++ b/drivers/target/target_core_alua.c @@ -455,11 +455,26 @@ out: return rc; } =20 -static inline int core_alua_state_nonoptimized( +static inline void set_ascq(struct se_cmd *cmd, u8 alua_ascq) +{ + /* + * Set SCSI additional sense code (ASC) to 'LUN Not Accessible'; + * The ALUA additional sense code qualifier (ASCQ) is determined + * by the ALUA primary or secondary access state.. + */ + pr_debug("[%s]: ALUA TG Port not available, " + "SenseKey: NOT_READY, ASC/ASCQ: " + "0x04/0x%02x\n", + cmd->se_tfo->get_fabric_name(), alua_ascq); + + cmd->scsi_asc =3D 0x04; + cmd->scsi_ascq =3D alua_ascq; +} + +static inline void core_alua_state_nonoptimized( struct se_cmd *cmd, unsigned char *cdb, - int nonop_delay_msecs, - u8 *alua_ascq) + int nonop_delay_msecs) { /* * Set SCF_ALUA_NON_OPTIMIZED here, this value will be checked @@ -468,13 +483,11 @@ static inline int core_alua_state_nonoptimized( */ cmd->se_cmd_flags |=3D SCF_ALUA_NON_OPTIMIZED; cmd->alua_nonop_delay =3D nonop_delay_msecs; - return 0; } =20 static inline int core_alua_state_lba_dependent( struct se_cmd *cmd, - struct t10_alua_tg_pt_gp *tg_pt_gp, - u8 *alua_ascq) + struct t10_alua_tg_pt_gp *tg_pt_gp) { struct se_device *dev =3D cmd->se_dev; u64 segment_size, segment_mult, sectors, lba; @@ -520,7 +533,7 @@ static inline int core_alua_state_lba_dependent( } if (!cur_map) { spin_unlock(&dev->t10_alua.lba_map_lock); - *alua_ascq =3D ASCQ_04H_ALUA_TG_PT_UNAVAILABLE; + set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE); return 1; } list_for_each_entry(map_mem, &cur_map->lba_map_mem_list, @@ -531,11 +544,11 @@ static inline int core_alua_state_lba_dependent( switch(map_mem->lba_map_mem_alua_state) { case ALUA_ACCESS_STATE_STANDBY: spin_unlock(&dev->t10_alua.lba_map_lock); - *alua_ascq =3D ASCQ_04H_ALUA_TG_PT_STANDBY; + set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY); return 1; case ALUA_ACCESS_STATE_UNAVAILABLE: spin_unlock(&dev->t10_alua.lba_map_lock); - *alua_ascq =3D ASCQ_04H_ALUA_TG_PT_UNAVAILABLE; + set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE); return 1; default: break; @@ -548,8 +561,7 @@ static inline int core_alua_state_lba_dependent( =20 static inline int core_alua_state_standby( struct se_cmd *cmd, - unsigned char *cdb, - u8 *alua_ascq) + unsigned char *cdb) { /* * Allowed CDBs for ALUA_ACCESS_STATE_STANDBY as defined by @@ -570,7 +582,7 @@ static inline int core_alua_state_standby( case MI_REPORT_TARGET_PGS: return 0; default: - *alua_ascq =3D ASCQ_04H_ALUA_TG_PT_STANDBY; + set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY); return 1; } case MAINTENANCE_OUT: @@ -578,7 +590,7 @@ static inline int core_alua_state_standby( case MO_SET_TARGET_PGS: return 0; default: - *alua_ascq =3D ASCQ_04H_ALUA_TG_PT_STANDBY; + set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY); return 1; } case REQUEST_SENSE: @@ -588,7 +600,7 @@ static inline int core_alua_state_standby( case WRITE_BUFFER: return 0; default: - *alua_ascq =3D ASCQ_04H_ALUA_TG_PT_STANDBY; + set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_STANDBY); return 1; } =20 @@ -597,8 +609,7 @@ static inline int core_alua_state_standby( =20 static inline int core_alua_state_unavailable( struct se_cmd *cmd, - unsigned char *cdb, - u8 *alua_ascq) + unsigned char *cdb) { /* * Allowed CDBs for ALUA_ACCESS_STATE_UNAVAILABLE as defined by @@ -613,7 +624,7 @@ static inline int core_alua_state_unavailable( case MI_REPORT_TARGET_PGS: return 0; default: - *alua_ascq =3D ASCQ_04H_ALUA_TG_PT_UNAVAILABLE; + set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE); return 1; } case MAINTENANCE_OUT: @@ -621,7 +632,7 @@ static inline int core_alua_state_unavailable( case MO_SET_TARGET_PGS: return 0; default: - *alua_ascq =3D ASCQ_04H_ALUA_TG_PT_UNAVAILABLE; + set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE); return 1; } case REQUEST_SENSE: @@ -629,7 +640,7 @@ static inline int core_alua_state_unavailable( case WRITE_BUFFER: return 0; default: - *alua_ascq =3D ASCQ_04H_ALUA_TG_PT_UNAVAILABLE; + set_ascq(cmd, ASCQ_04H_ALUA_TG_PT_UNAVAILABLE); return 1; } =20 @@ -638,8 +649,7 @@ static inline int core_alua_state_unavailable( =20 static inline int core_alua_state_transition( struct se_cmd *cmd, - unsigned char *cdb, - u8 *alua_ascq) + unsigned char *cdb) { /* * Allowed CDBs for ALUA_ACCESS_STATE_TRANSITION as defined by @@ -654,7 +664,7 @@ static inline int core_alua_state_transition( case MI_REPORT_TARGET_PGS: return 0; default: - *alua_ascq =3D ASCQ_04H_ALUA_STATE_TRANSITION; + set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION); return 1; } case REQUEST_SENSE: @@ -662,7 +672,7 @@ static inline int core_alua_state_transition( case WRITE_BUFFER: return 0; default: - *alua_ascq =3D ASCQ_04H_ALUA_STATE_TRANSITION; + set_ascq(cmd, ASCQ_04H_ALUA_STATE_TRANSITION); return 1; } =20 @@ -684,8 +694,6 @@ target_alua_state_check(struct se_cmd *cmd) struct t10_alua_tg_pt_gp *tg_pt_gp; struct t10_alua_tg_pt_gp_member *tg_pt_gp_mem; int out_alua_state, nonop_delay_msecs; - u8 alua_ascq; - int ret; =20 if (dev->se_hba->hba_flags & HBA_FLAGS_INTERNAL_USE) return 0; @@ -701,9 +709,8 @@ target_alua_state_check(struct se_cmd *cmd) if (atomic_read(&port->sep_tg_pt_secondary_offline)) { pr_debug("ALUA: Got secondary offline status for local" " target port\n"); - alua_ascq =3D ASCQ_04H_ALUA_OFFLINE; - ret =3D 1; - goto out; + set_ascq(cmd, ASCQ_04H_ALUA_OFFLINE); + return TCM_CHECK_CONDITION_NOT_READY; } /* * Second, obtain the struct t10_alua_tg_pt_gp_member pointer to the @@ -731,20 +738,23 @@ target_alua_state_check(struct se_cmd *cmd) =20 switch (out_alua_state) { case ALUA_ACCESS_STATE_ACTIVE_NON_OPTIMIZED: - ret =3D core_alua_state_nonoptimized(cmd, cdb, - nonop_delay_msecs, &alua_ascq); + core_alua_state_nonoptimized(cmd, cdb, nonop_delay_msecs); break; case ALUA_ACCESS_STATE_STANDBY: - ret =3D core_alua_state_standby(cmd, cdb, &alua_ascq); + if (core_alua_state_standby(cmd, cdb)) + return TCM_CHECK_CONDITION_NOT_READY; break; case ALUA_ACCESS_STATE_UNAVAILABLE: - ret =3D core_alua_state_unavailable(cmd, cdb, &alua_ascq); + if (core_alua_state_unavailable(cmd, cdb)) + return TCM_CHECK_CONDITION_NOT_READY; break; case ALUA_ACCESS_STATE_TRANSITION: - ret =3D core_alua_state_transition(cmd, cdb, &alua_ascq); + if (core_alua_state_transition(cmd, cdb)) + return TCM_CHECK_CONDITION_NOT_READY; break; case ALUA_ACCESS_STATE_LBA_DEPENDENT: - ret =3D core_alua_state_lba_dependent(cmd, tg_pt_gp, &alua_ascq); + if (core_alua_state_lba_dependent(cmd, tg_pt_gp)) + return TCM_CHECK_CONDITION_NOT_READY; break; /* * OFFLINE is a secondary ALUA target port group access state, that i= s @@ -757,23 +767,6 @@ target_alua_state_check(struct se_cmd *cmd) return TCM_INVALID_CDB_FIELD; } =20 -out: - if (ret > 0) { - /* - * Set SCSI additional sense code (ASC) to 'LUN Not Accessible'; - * The ALUA additional sense code qualifier (ASCQ) is determined - * by the ALUA primary or secondary access state.. - */ - pr_debug("[%s]: ALUA TG Port not available, " - "SenseKey: NOT_READY, ASC/ASCQ: " - "0x04/0x%02x\n", - cmd->se_tfo->get_fabric_name(), alua_ascq); - - cmd->scsi_asc =3D 0x04; - cmd->scsi_ascq =3D alua_ascq; - return TCM_CHECK_CONDITION_NOT_READY; - } - return 0; } =20 --=20 1.8.5.3