From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Ewan D. Milne" Subject: [PATCH RFC 1/9] [SCSI] Detect overflow of sense data buffer Date: Fri, 18 Jan 2013 11:27:06 -0500 Message-ID: <1358526434-1173-2-git-send-email-emilne@redhat.com> References: <1358526434-1173-1-git-send-email-emilne@redhat.com> Return-path: Received: from mx1.redhat.com ([209.132.183.28]:61975 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753253Ab3ARQ1Q (ORCPT ); Fri, 18 Jan 2013 11:27:16 -0500 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id r0IGRG9S008147 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Fri, 18 Jan 2013 11:27:16 -0500 Received: from emilne.csb (dhcp-186-175.bos.redhat.com [10.16.186.175]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id r0IGRFnE026564 for ; Fri, 18 Jan 2013 11:27:16 -0500 In-Reply-To: <1358526434-1173-1-git-send-email-emilne@redhat.com> Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: linux-scsi@vger.kernel.org From: "Ewan D. Milne" Added code to SCSI mid-layer sense processing to detect the SDAT_OVFL bit in Fixed or Descriptor format sense data, and log a kernel message if the device reported that the sense data did not fit in the buffer. Signed-off-by: Ewan D. Milne --- drivers/scsi/scsi_debug.c | 35 +++++++++++++++++++++++++++++++++++ drivers/scsi/scsi_error.c | 9 ++++++++- include/scsi/scsi_eh.h | 1 + 3 files changed, 44 insertions(+), 1 deletion(-) diff --git a/drivers/scsi/scsi_debug.c b/drivers/scsi/scsi_debug.c index 182d5a5..88f6d16 100644 --- a/drivers/scsi/scsi_debug.c +++ b/drivers/scsi/scsi_debug.c @@ -230,6 +230,7 @@ struct sdebug_dev_info { char reset; char stopped; char used; + char sense_pending; }; struct sdebug_host_info { @@ -3205,6 +3206,32 @@ static ssize_t sdebug_map_show(struct device_driver *ddp, char *buf) } DRIVER_ATTR(map, S_IRUGO, sdebug_map_show, NULL); +static ssize_t sdebug_sense_overflow_store(struct device_driver *ddp, + const char *buf, size_t count) +{ + int n; + struct sdebug_host_info *sdbg_host; + struct sdebug_dev_info *devip; + + if ((count > 0) && (1 == sscanf(buf, "%d", &n)) && (n >= 0)) { + spin_lock(&sdebug_host_list_lock); + list_for_each_entry(sdbg_host, &sdebug_host_list, host_list) { + list_for_each_entry(devip, &sdbg_host->dev_info_list, + dev_list) { + mk_sense_buffer(devip, NO_SENSE, 0, 0); + if (scsi_debug_dsense) + devip->sense_buff[4] = 0x80; + else + devip->sense_buff[2] = 0x10; + devip->sense_pending = 1; + } + } + spin_unlock(&sdebug_host_list_lock); + return count; + } + return -EINVAL; +} +DRIVER_ATTR(sense_overflow, S_IWUSR, NULL, sdebug_sense_overflow_store); /* Note: The following function creates attribute files in the /sys/bus/pseudo/drivers/scsi_debug directory. The advantage of these @@ -3239,11 +3266,15 @@ static int do_create_driverfs_files(void) ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_guard); ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_ato); ret |= driver_create_file(&sdebug_driverfs_driver, &driver_attr_map); + ret |= driver_create_file(&sdebug_driverfs_driver, + &driver_attr_sense_overflow); return ret; } static void do_remove_driverfs_files(void) { + driver_remove_file(&sdebug_driverfs_driver, + &driver_attr_sense_overflow); driver_remove_file(&sdebug_driverfs_driver, &driver_attr_map); driver_remove_file(&sdebug_driverfs_driver, &driver_attr_ato); driver_remove_file(&sdebug_driverfs_driver, &driver_attr_guard); @@ -3926,6 +3957,10 @@ write: errsts = check_condition_result; break; } + if (!errsts && devip->sense_pending) { + devip->sense_pending = 0; + errsts = check_condition_result; + } return schedule_resp(SCpnt, devip, done, errsts, (delay_override ? 0 : scsi_debug_delay)); } diff --git a/drivers/scsi/scsi_error.c b/drivers/scsi/scsi_error.c index d0f71e5..20669836 100644 --- a/drivers/scsi/scsi_error.c +++ b/drivers/scsi/scsi_error.c @@ -241,6 +241,9 @@ static int scsi_check_sense(struct scsi_cmnd *scmd) if (! scsi_command_normalize_sense(scmd, &sshdr)) return FAILED; /* no valid sense data */ + if (sshdr.overflow) + scmd_printk(KERN_WARNING, scmd, "Sense data overflow"); + if (scsi_sense_is_deferred(&sshdr)) return NEEDS_RETRY; @@ -2059,14 +2062,18 @@ int scsi_normalize_sense(const u8 *sense_buffer, int sb_len, sshdr->asc = sense_buffer[2]; if (sb_len > 3) sshdr->ascq = sense_buffer[3]; + if (sb_len > 4) + sshdr->overflow = ((sense_buffer[4] & 0x80) != 0); if (sb_len > 7) sshdr->additional_length = sense_buffer[7]; } else { /* * fixed format */ - if (sb_len > 2) + if (sb_len > 2) { + sshdr->overflow = ((sense_buffer[2] & 0x10) != 0); sshdr->sense_key = (sense_buffer[2] & 0xf); + } if (sb_len > 7) { sb_len = (sb_len < (sense_buffer[7] + 8)) ? sb_len : (sense_buffer[7] + 8); diff --git a/include/scsi/scsi_eh.h b/include/scsi/scsi_eh.h index 06a8790..ddf58cf 100644 --- a/include/scsi/scsi_eh.h +++ b/include/scsi/scsi_eh.h @@ -25,6 +25,7 @@ struct scsi_sense_hdr { /* See SPC-3 section 4.5 */ u8 byte5; u8 byte6; u8 additional_length; /* always 0 for fixed sense format */ + unsigned int overflow:1; /* sense data overflow */ }; static inline int scsi_sense_valid(struct scsi_sense_hdr *sshdr) -- 1.7.11.7