SCSI mid-layer multi-path IO changes
drivers/scsi/scsi_paths.h | 146 ++++++++++++++++
drivers/scsi/scsi_proc.c | 8
drivers/scsi/scsi_scan.c | 408 +++++++++++++++++++++++++++-------------------
drivers/scsi/scsi_syms.c | 7
include/scsi/scsi.h | 23 ++
5 files changed, 422 insertions(+), 170 deletions(-)
diff -Nru a/drivers/scsi/scsi_paths.h b/drivers/scsi/scsi_paths.h
--- /dev/null Wed Dec 31 16:00:00 1969
+++ b/drivers/scsi/scsi_paths.h Fri Oct 25 11:26:48 2002
@@ -0,0 +1,146 @@
+/*
+ * Scsi Multi-path Support Library
+ *
+ * Copyright (c) 2002 IBM
+ *
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or (at
+ * your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for more
+ * details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * Send feedback to <patmans@us.ibm.com> and/or andmike@us.ibm.com
+ */
+
+#ifndef _SCSI_PATHS_H
+#define _SCSI_PATHS_H
+
+#include <linux/list.h>
+/*
+ * XXX asm/mmzone.h holds the xxx_to_nid and other information needed, but
+ * right now it is x86 specific, as well as patch specific, so a way is
+ * needed to correctly include it (rather than conditionally). The
+ * asm-i386 mmzone.h is created as part of the topo patch, and xxx_to_nid
+ * api's are added by pdorwin patch. The following is ugly and not even
+ * correct, since CONFIG_X86_NUMAQ means build for IBM NUMAQ box, it does
+ * not mean the API or even asm/mmzone.h exist.
+ */
+#ifdef CONFIG_X86_NUMAQ
+#include <asm/mmzone.h>
+#endif
+
+
+#if !defined(MAX_NUMNODES) || (MAX_NUMNODES == 0)
+#error Undefined or unexpected value of MAX_NUMNODES
+#endif
+
+#if MAX_NUMNODES == 1
+/*
+ * No NUMA support is configured or no NUMA patches. Use one
+ * last active pointer (SCSI_MAX_ACTIVE_LIST), and have one
+ * (SCSI_PATHS_MAX_PATH_LISTS) list of active paths.
+ */
+#define SCSI_MAX_ACTIVE_LIST 1
+#define SCSI_PATHS_MAX_PATH_LISTS 1
+#define req_to_nid(req) 0
+#define scsihost_to_node(host) 0
+#define page_to_nid(page) 0
+#else
+/*
+ * NUMA support is configured, use one last active pointer per maximum
+ * number of nodes plus one last active pointer for all paths
+ * (SCSI_MAX_ACTIVE_LIST), and have two lists of paths
+ * (SCSI_PATHS_MAX_PATH_LISTS) - one for all paths and one for node local
+ * paths.
+ */
+#define SCSI_MAX_ACTIVE_LIST (MAX_NUMNODES + 1)
+#define SCSI_PATHS_MAX_PATH_LISTS 2
+
+/*
+ * XXX use a real page_to_nid() API.
+ */
+#define page_to_nid(page) pfn_to_nid(page_to_pfn(page))
+/*
+ * FIXME This does not properly handle requests with req->bio NULL, these are
+ * generated via scsi_do_req calls. Fix this by putting a node number in the
+ * request, and have scsi_do_req() and __make_request() set req->node.
+ */
+#define req_to_nid(req) \
+ (((req)->bio == NULL) ? 0 : page_to_nid(bio_page((req)->bio)))
+#endif
+
+#define SCSI_PATHS_ALL_LIST (SCSI_MAX_ACTIVE_LIST - 1)
+
+#define SCSI_ALL_ACTIVE_NEXT_LIST 0
+#define SCSI_NID_ACTIVE_NEXT_LIST 1
+
+/**
+ * enum scsi_path_policy - Path selection policy.
+ * @SCSI_PATH_POLICY_LPU: Use the same path that was used for the last IO
+ * @SCSI_PATH_POLICY_ROUND_ROBIN: Round robin across all active paths
+ **/
+enum scsi_path_policy {
+ SCSI_PATH_POLICY_LPU = 1,
+ SCSI_PATH_POLICY_ROUND_ROBIN
+};
+
+/**
+ * enum scsi_path_state - Path state flags
+ * @SCSI_PATH_STATE_GOOD: The path is active for IO.
+ * @SCSI_PATH_STATE_FAILING: The path might be failing (XXX not fully
+ * implemented yet)
+ * @SCSI_PATH_STATE_DEAD: The path has failed.
+ **/
+enum scsi_path_state {
+ SCSI_PATH_STATE_GOOD = 1,
+ SCSI_PATH_STATE_FAILING,
+ SCSI_PATH_STATE_DEAD
+};
+
+/**
+ * struct scsi_path - A single scsi path
+ * @sp_path_list: list head for all paths
+ * @sp_active_next: circular list of all active paths, list at 0 is for all
+ * active paths, the list at 1 for all active paths on a given node id.
+ * @sp_path_id: id of path (host/channel/target/lun)
+ * @sp_state: state of path
+ * @sp_failures: number of failures on this path
+ * @sp_weight: path weight 0 best, higher values worse (XXX path weighting
+ * is not implemented, for now setting this has no affect)
+ **/
+struct scsi_path {
+ struct list_head sp_path_list;
+ struct scsi_path *sp_active_next[SCSI_PATHS_MAX_PATH_LISTS];
+ struct scsi_path_id sp_path_id;
+ enum scsi_path_state sp_state;
+ unsigned int sp_failures;
+ unsigned int sp_weight;
+};
+
+/**
+ * struct scsi_mpath - All paths for a scsi device
+ * @scsi_mp_paths: list of scsi paths
+ * @scsi_mp_last_active: last active path used, one for each node, plus
+ * one for the all active list.
+ * @scsi_mp_path_policy: path selection policy - round robin or last used
+ * @scsi_mp_path_active_cnt: number of paths XXX change to an array
+ **/
+struct scsi_mpath {
+ struct list_head scsi_mp_paths_head;
+ struct scsi_path *scsi_mp_last_active[SCSI_MAX_ACTIVE_LIST];
+ unsigned int scsi_mp_path_active_cnt[SCSI_MAX_ACTIVE_LIST];
+ enum scsi_path_policy scsi_mp_path_policy;
+};
+
+#endif
diff -Nru a/drivers/scsi/scsi_proc.c b/drivers/scsi/scsi_proc.c
--- a/drivers/scsi/scsi_proc.c Fri Oct 25 11:26:47 2002
+++ b/drivers/scsi/scsi_proc.c Fri Oct 25 11:26:47 2002
@@ -264,15 +264,15 @@
return (cmdIndex);
}
-void proc_print_scsidevice(Scsi_Device * scd, char *buffer, int *size, int len)
+void proc_print_scsidevice(Scsi_Device *scd, char *buffer, int *size, int len)
{
int x, y = *size;
extern const char *const scsi_device_types[MAX_SCSI_DEVICE_CODE];
- y = sprintf(buffer + len,
- "Host: scsi%d Channel: %02d Id: %02d Lun: %02d\n Vendor: ",
- scd->host->host_no, scd->channel, scd->id, scd->lun);
+ y = scsi_paths_proc_print_paths(scd, buffer + len,
+ "Host: scsi%d Channel: %02d Id: %02d Lun: %02d\n");
+ y += sprintf(buffer + len + y, "Vendor: ");
for (x = 0; x < 8; x++) {
if (scd->vendor[x] >= 0x20)
y += sprintf(buffer + len + y, "%c", scd->vendor[x]);
diff -Nru a/drivers/scsi/scsi_scan.c b/drivers/scsi/scsi_scan.c
--- a/drivers/scsi/scsi_scan.c Fri Oct 25 11:26:48 2002
+++ b/drivers/scsi/scsi_scan.c Fri Oct 25 11:26:48 2002
@@ -189,26 +189,22 @@
" SCSI scanning, some SCSI devices might not be configured\n"
/*
- * Prefix values for the SCSI id's (stored in driverfs name field)
- */
-#define SCSI_UID_SER_NUM 'S'
-#define SCSI_UID_UNKNOWN 'Z'
-
-/*
- * Return values of some of the scanning functions.
+ * Return values for (some of) the scanning functions, these are masks.
*
* SCSI_SCAN_NO_RESPONSE: no valid response received from the target, this
* includes allocation or general failures preventing IO from being sent.
*
- * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is available
- * on the given LUN.
+ * SCSI_SCAN_TARGET_PRESENT: target responded, a device may or may not be
+ * present on a given LUN in such cases.
*
- * SCSI_SCAN_LUN_PRESENT: target responded, and a device is available on a
- * given LUN.
+ * SCSI_SCAN_LUN_PRESENT: A device is available on a given LUN.
+ *
+ * SCSI_SCAN_NEW_LUN: This is a pre-existing device with a new path.
*/
-#define SCSI_SCAN_NO_RESPONSE 0
-#define SCSI_SCAN_TARGET_PRESENT 1
-#define SCSI_SCAN_LUN_PRESENT 2
+#define SCSI_SCAN_NO_RESPONSE 0x00
+#define SCSI_SCAN_TARGET_PRESENT 0x01
+#define SCSI_SCAN_LUN_PRESENT 0x02
+#define SCSI_SCAN_NEW_LUN 0x04
static char *scsi_null_device_strs = "nullnullnullnull";
@@ -486,9 +482,8 @@
* scsi_alloc_sdev - allocate and setup a Scsi_Device
*
* Description:
- * Allocate, initialize for io, and return a pointer to a Scsi_Device.
- * Stores the @shost, @channel, @id, and @lun in the Scsi_Device, and
- * adds Scsi_Device to the appropriate list.
+ * Allocate, initialize for io, add to the device list, and return a
+ * pointer to a Scsi_Device.
*
* Return value:
* Scsi_Device pointer, or NULL on failure.
@@ -506,10 +501,16 @@
sdev->vendor = scsi_null_device_strs;
sdev->model = scsi_null_device_strs;
sdev->rev = scsi_null_device_strs;
- sdev->host = shost;
- sdev->id = id;
- sdev->lun = lun;
- sdev->channel = channel;
+
+ /*
+ * XXX move this out, if it is overly redundant; if so, be
+ * sure to call scsi_add_path somewhere, or modify
+ * scsi_replace_path.
+ */
+ if (scsi_add_path(sdev, shost, channel, id, lun)) {
+ kfree(sdev);
+ return (NULL);
+ }
sdev->online = TRUE;
/*
* Some low level driver could use device->type
@@ -527,45 +528,12 @@
scsi_initialize_merge_fn(sdev);
init_waitqueue_head(&sdev->scpnt_wait);
- /*
- * Add it to the end of the shost->host_queue list.
- */
- if (shost->host_queue != NULL) {
- sdev->prev = shost->host_queue;
- while (sdev->prev->next != NULL)
- sdev->prev = sdev->prev->next;
- sdev->prev->next = sdev;
- } else
- shost->host_queue = sdev;
-
+ scsi_add_scsi_device(sdev, shost);
}
return (sdev);
}
/**
- * scsi_free_sdev - cleanup and free a Scsi_Device
- * @sdev: cleanup and free this Scsi_Device
- *
- * Description:
- * Undo the actions in scsi_alloc_sdev, including removing @sdev from
- * the list, and freeing @sdev.
- **/
-static void scsi_free_sdev(Scsi_Device *sdev)
-{
- if (sdev->prev != NULL)
- sdev->prev->next = sdev->next;
- else
- sdev->host->host_queue = sdev->next;
- if (sdev->next != NULL)
- sdev->next->prev = sdev->prev;
-
- blk_cleanup_queue(&sdev->request_queue);
- if (sdev->inquiry != NULL)
- kfree(sdev->inquiry);
- kfree(sdev);
-}
-
-/**
* scsi_check_id_size - check if size fits in the driverfs name
* @sdev: Scsi_Device to use for error message
* @size: the length of the id we want to store
@@ -581,11 +549,10 @@
static int scsi_check_id_size(Scsi_Device *sdev, int size)
{
if (size > DEVICE_NAME_SIZE) {
- printk(KERN_WARNING "scsi scan: host %d channel %d id %d lun %d"
- " identifier too long, length %d, max %d. Device might"
- " be improperly identified.\n", sdev->host->host_no,
- sdev->channel, sdev->id, sdev->lun, size,
- DEVICE_NAME_SIZE);
+ printk(KERN_WARNING "scsi scan: ");
+ scsi_paths_printk(sdev, " ", "host %d channel %d id %d lun %d");
+ printk(" identifier too long, length %d, max %d. Device might"
+ " be improperly identified.\n", size, DEVICE_NAME_SIZE);
return 1;
} else
return 0;
@@ -603,7 +570,8 @@
* Return:
* A pointer to data containing the results on success, else NULL.
**/
-unsigned char *scsi_get_evpd_page(Scsi_Device *sdev, Scsi_Request *sreq)
+unsigned char *scsi_get_evpd_page(Scsi_Device *sdev, Scsi_Request *sreq,
+ struct scsi_path_id *pathid)
{
unsigned char *evpd_page;
unsigned char scsi_cmd[MAX_COMMAND_SIZE];
@@ -611,15 +579,15 @@
retry:
evpd_page = kmalloc(max_lgth, GFP_ATOMIC |
- (sdev->host->unchecked_isa_dma) ?
+ (pathid->spi_shpnt->unchecked_isa_dma) ?
GFP_DMA : 0);
if (!evpd_page) {
- printk(KERN_WARNING "scsi scan: Allocation failure identifying"
- " host %d channel %d id %d lun %d, device might be"
- " improperly identified.\n", sdev->host->host_no,
- sdev->channel, sdev->id, sdev->lun);
+ printk(KERN_WARNING "scsi scan: Allocation failure identifying ");
+ scsi_paths_printk(sdev, " ", "host %d channel %d id %d lun %d");
+ printk("device might be improperly identified.\n");
return NULL;
}
+ memset(evpd_page, 0, max_lgth);
memset(scsi_cmd, 0, MAX_COMMAND_SIZE);
scsi_cmd[0] = INQUIRY;
@@ -856,24 +824,26 @@
* 0: Failure
* 1: Success
**/
-int scsi_get_deviceid(Scsi_Device *sdev, Scsi_Request *sreq)
+int scsi_get_deviceid(Scsi_Device *sdev, Scsi_Request *sreq,
+ struct scsi_path_id *pathid)
{
unsigned char *id_page;
unsigned char scsi_cmd[MAX_COMMAND_SIZE];
int id_idx, scnt, ret;
int max_lgth = 255;
+
retry:
id_page = kmalloc(max_lgth, GFP_ATOMIC |
- (sdev->host->unchecked_isa_dma) ?
+ (pathid->spi_shpnt->unchecked_isa_dma) ?
GFP_DMA : 0);
if (!id_page) {
- printk(KERN_WARNING "scsi scan: Allocation failure identifying"
- " host %d channel %d id %d lun %d, device might be"
- " improperly identified.\n", sdev->host->host_no,
- sdev->channel, sdev->id, sdev->lun);
+ printk(KERN_WARNING "scsi scan: Allocation failure identifying ");
+ scsi_paths_printk(sdev, " ", "host %d channel %d id %d lun %d");
+ printk("device might be improperly identified.\n");
return 0;
}
+ memset(id_page, 0, max_lgth);
memset(scsi_cmd, 0, MAX_COMMAND_SIZE);
scsi_cmd[0] = INQUIRY;
@@ -916,8 +886,9 @@
SCSI_LOG_SCAN_BUS(4, printk(KERN_INFO
"scsi scan: host %d channel %d id %d lun %d"
" used id desc %d/%d/%d\n",
- sdev->host->host_no, sdev->channel,
- sdev->id, sdev->lun,
+ pathid->spi_shpnt->host_no,
+ pathid->spi_channel, pathid->spi_id,
+ pathid->spi_lun,
id_search_list[id_idx].id_type,
id_search_list[id_idx].naa_type,
id_search_list[id_idx].code_set));
@@ -927,8 +898,9 @@
SCSI_LOG_SCAN_BUS(4, printk(KERN_INFO
"scsi scan: host %d channel %d id %d lun %d"
" no match/error id desc %d/%d/%d\n",
- sdev->host->host_no, sdev->channel,
- sdev->id, sdev->lun,
+ pathid->spi_shpnt->host_no,
+ pathid->spi_channel, pathid->spi_id,
+ pathid->spi_lun,
id_search_list[id_idx].id_type,
id_search_list[id_idx].naa_type,
id_search_list[id_idx].code_set));
@@ -959,7 +931,8 @@
* 0: Failure
* 1: Success
**/
-int scsi_get_serialnumber(Scsi_Device *sdev, Scsi_Request *sreq)
+int scsi_get_serialnumber(Scsi_Device *sdev, Scsi_Request *sreq,
+ struct scsi_path_id *pathid)
{
unsigned char *serialnumber_page;
unsigned char scsi_cmd[MAX_COMMAND_SIZE];
@@ -967,15 +940,15 @@
retry:
serialnumber_page = kmalloc(max_lgth, GFP_ATOMIC |
- (sdev->host->unchecked_isa_dma) ?
+ (pathid->spi_shpnt->unchecked_isa_dma) ?
GFP_DMA : 0);
if (!serialnumber_page) {
- printk(KERN_WARNING "scsi scan: Allocation failure identifying"
- " host %d channel %d id %d lun %d, device might be"
- " improperly identified.\n", sdev->host->host_no,
- sdev->channel, sdev->id, sdev->lun);
+ printk(KERN_WARNING "scsi scan: Allocation failure identifying ");
+ scsi_paths_printk(sdev, " ", "host %d channel %d id %d lun %d");
+ printk("device might be improperly identified.\n");
return 0;
}
+ memset(serialnumber_page, 0, max_lgth);
memset(scsi_cmd, 0, MAX_COMMAND_SIZE);
scsi_cmd[0] = INQUIRY;
@@ -1074,14 +1047,20 @@
{
unsigned char *evpd_page = NULL;
int cnt;
+ struct scsi_path_id pathid;
memset(sdev->sdev_driverfs_dev.name, 0, DEVICE_NAME_SIZE);
- evpd_page = scsi_get_evpd_page(sdev, sreq);
+ if (scsi_get_path(sdev, &pathid)) {
+ printk(KERN_ERR "scsi scan: no path to scan device.\n");
+ scsi_get_default_name(sdev);
+ return;
+ }
+ evpd_page = scsi_get_evpd_page(sdev, sreq, &pathid);
if (evpd_page == NULL) {
/*
* try to obtain serial number anyway
*/
- (void)scsi_get_serialnumber(sdev, sreq);
+ (void)scsi_get_serialnumber(sdev, sreq, &pathid);
} else {
/*
* XXX search high to low, since the pages are lowest to
@@ -1089,23 +1068,25 @@
*/
for(cnt = 4; cnt <= evpd_page[3] + 3; cnt++)
if (evpd_page[cnt] == 0x83)
- if (scsi_get_deviceid(sdev, sreq))
+ if (scsi_get_deviceid(sdev, sreq, &pathid))
goto leave;
for(cnt = 4; cnt <= evpd_page[3] + 3; cnt++)
if (evpd_page[cnt] == 0x80)
- if (scsi_get_serialnumber(sdev, sreq))
+ if (scsi_get_serialnumber(sdev, sreq, &pathid))
goto leave;
- if (sdev->sdev_driverfs_dev.name[0] == 0)
- scsi_get_default_name(sdev);
}
+ if (sdev->sdev_driverfs_dev.name[0] == 0)
+ scsi_get_default_name(sdev);
leave:
if (evpd_page) kfree(evpd_page);
- SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: host %d channel %d"
- " id %d lun %d name/id: '%s'\n", sdev->host->host_no,
- sdev->channel, sdev->id, sdev->lun, sdev->sdev_driverfs_dev.name));
+ SCSI_LOG_SCAN_BUS(3, {
+ printk(KERN_INFO "scsi scan: ");
+ scsi_paths_printk(sdev, " ", "host %d channel %d id %d lun %d");
+ printk(" name/id: '%s'\n", sdev->sdev_driverfs_dev.name);
+ });
return;
}
@@ -1124,9 +1105,10 @@
{
int res = SCSI_2;
Scsi_Device *sdev;
+ struct scsi_traverse_hndl strav_hndl;
- for (sdev = shost->host_queue; sdev; sdev = sdev->next)
- if ((id == sdev->id) && (channel == sdev->channel))
+ scsi_for_each_sdev_lun (&strav_hndl, sdev, shost->host_no,
+ channel, id)
return (int) sdev->scsi_level;
/*
* FIXME No matching target id is configured, this needs to get
@@ -1156,9 +1138,10 @@
unsigned char scsi_cmd[MAX_COMMAND_SIZE];
int possible_inq_resp_len;
- SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: INQUIRY to host %d"
- " channel %d id %d lun %d\n", sdev->host->host_no,
- sdev->channel, sdev->id, sdev->lun));
+ SCSI_LOG_SCAN_BUS(3, {
+ printk(KERN_INFO "scsi scan: INQUIRY to ");
+ scsi_paths_printk(sdev, " ", "host %d channel %d id %d lun %d\n");
+ });
memset(scsi_cmd, 0, 6);
scsi_cmd[0] = INQUIRY;
@@ -1271,6 +1254,55 @@
return;
}
+#ifdef CONFIG_SCSI_MULTI_PATH_IO
+/*
+ * scsi_check_sdev_id - check if a path already exist for sdev, if so add
+ * a new path, and return an appropriate value.
+ * @sdev: check for exiting paths on this
+ * @path: path to sdev
+ *
+ * Returns 0 if this is a new device, else a SCSI_SCAN_ mask value.
+ */
+static int scsi_check_sdev_id(Scsi_Device *sdev, Scsi_Device **sdevnew,
+ struct scsi_path_id *pathid)
+{
+ Scsi_Device *sdev_found;
+
+ /*
+ * XXX check here if host adapter is OK with multipath, or if a
+ * particular device is white or black listed for a unique id.
+ */
+
+ /*
+ * sdev is linked onto the list, so we need to let the lookup id
+ * know to skip sdev.
+ */
+ sdev_found = scsi_lookup_id(sdev->sdev_driverfs_dev.name, sdev);
+ if (sdev_found != NULL) {
+ /*
+ * Found a new path to an existing device, remove the just
+ * allocated sdev.
+ *
+ * FIXME for now don't add any driverfs info for the new path.
+ */
+ scsi_remove_scsi_device(sdev);
+ (void)scsi_add_path(sdev_found, pathid->spi_shpnt,
+ pathid->spi_channel, pathid->spi_id,
+ pathid->spi_lun);
+ if (sdevnew != NULL)
+ *sdevnew = sdev_found;
+ return (SCSI_SCAN_TARGET_PRESENT | SCSI_SCAN_LUN_PRESENT);
+ }
+ return 0;
+}
+#else
+static int scsi_check_sdev_id(Scsi_Device *sdev, Scsi_Device **sdevnew,
+ struct scsi_path_id *pathid)
+{
+ return 0;
+}
+#endif
+
/**
* scsi_add_lun - allocate and fully initialze a Scsi_Device
* @sdevscan: holds information to be stored in the new Scsi_Device
@@ -1285,9 +1317,7 @@
* NULL, store the address of the new Scsi_Device in *@sdevnew (needed
* when scanning a particular LUN).
*
- * Return:
- * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a Scsi_Device
- * SCSI_SCAN_LUN_PRESENT: a new Scsi_Device was allocated and initialized
+ * Returns a SCSI_SCAN_ mask value.
**/
static int scsi_add_lun(Scsi_Device *sdevscan, Scsi_Device **sdevnew,
Scsi_Request *sreq, char *inq_result, int *bflags)
@@ -1296,9 +1326,20 @@
struct Scsi_Device_Template *sdt;
char devname[64];
extern devfs_handle_t scsi_devfs_handle;
+ struct scsi_path_id pathid;
+ int ret;
- sdev = scsi_alloc_sdev(sdevscan->host, sdevscan->channel,
- sdevscan->id, sdevscan->lun);
+ /*
+ * sdevscan must have only one path, add it to this device. XXX
+ * this is a bit ugly, there must be a better solution, maybe pass
+ * a scsi_path_id everywhere.
+ */
+ if (scsi_get_path(sdevscan, &pathid)) {
+ printk(KERN_ERR "scsi scan: no path to scan device.\n");
+ return SCSI_SCAN_NO_RESPONSE;
+ }
+ sdev = scsi_alloc_sdev(pathid.spi_shpnt, pathid.spi_channel,
+ pathid.spi_id, pathid.spi_lun);
if (sdev == NULL)
return SCSI_SCAN_NO_RESPONSE;
@@ -1316,7 +1357,7 @@
sdev->inquiry_len = sdevscan->inquiry_len;
sdev->inquiry = kmalloc(sdev->inquiry_len, GFP_ATOMIC);
if (sdev->inquiry == NULL) {
- scsi_free_sdev(sdev);
+ scsi_remove_scsi_device(sdev);
return SCSI_SCAN_NO_RESPONSE;
}
@@ -1325,6 +1366,22 @@
sdev->model = (char *) (sdev->inquiry + 16);
sdev->rev = (char *) (sdev->inquiry + 32);
+ /*
+ * XXX move the identifier and driverfs/devfs setup to a new
+ * function
+ *
+ * scsi_load_identifier is the only reason sreq is needed in this
+ * function; it also requires that the inquiry strings be set up.
+ */
+ scsi_load_identifier(sdev, sreq);
+
+ /*
+ * Check for multi-path device.
+ */
+ ret = scsi_check_sdev_id(sdev, sdevnew, &pathid);
+ if (ret)
+ return(ret);
+
if (*bflags & BLIST_ISROM) {
/*
* It would be better to modify sdev->type, and set
@@ -1395,20 +1452,12 @@
sdev->sdtr = 1;
/*
- * XXX maybe move the identifier and driverfs/devfs setup to a new
- * function, and call them after this function is called.
- *
- * scsi_load_identifier is the only reason sreq is needed in this
- * function.
- */
- scsi_load_identifier(sdev, sreq);
-
- /*
* create driverfs files
*/
sprintf(sdev->sdev_driverfs_dev.bus_id,"%d:%d:%d:%d",
- sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
- sdev->sdev_driverfs_dev.parent = &sdev->host->host_driverfs_dev;
+ pathid.spi_shpnt->host_no, pathid.spi_channel, pathid.spi_id,
+ pathid.spi_lun);
+ sdev->sdev_driverfs_dev.parent = &pathid.spi_shpnt->host_driverfs_dev;
sdev->sdev_driverfs_dev.bus = &scsi_driverfs_bus_type;
device_register(&sdev->sdev_driverfs_dev);
@@ -1418,7 +1467,8 @@
device_create_file(&sdev->sdev_driverfs_dev, &dev_attr_type);
sprintf(devname, "host%d/bus%d/target%d/lun%d",
- sdev->host->host_no, sdev->channel, sdev->id, sdev->lun);
+ pathid.spi_shpnt->host_no, pathid.spi_channel, pathid.spi_id,
+ pathid.spi_lun);
if (sdev->de)
printk(KERN_WARNING "scsi devfs dir: \"%s\" already exists\n",
devname);
@@ -1454,19 +1504,20 @@
if (sdt->detect)
sdev->attached += (*sdt->detect) (sdev);
- if (sdev->host->hostt->slave_attach != NULL) {
- if (sdev->host->hostt->slave_attach(sdev) != 0) {
+ if (pathid.spi_shpnt->hostt->slave_attach != NULL) {
+ if (pathid.spi_shpnt->hostt->slave_attach(sdev) != 0) {
printk(KERN_INFO "%s: scsi_add_lun: failed low level driver attach, setting device offline", devname);
sdev->online = FALSE;
}
- } else if(sdev->host->cmd_per_lun) {
- scsi_adjust_queue_depth(sdev, 0, sdev->host->cmd_per_lun);
+ } else if(pathid.spi_shpnt->cmd_per_lun) {
+ scsi_adjust_queue_depth(sdev, 0, pathid.spi_shpnt->cmd_per_lun);
}
if (sdevnew != NULL)
*sdevnew = sdev;
- return SCSI_SCAN_LUN_PRESENT;
+ return (SCSI_SCAN_TARGET_PRESENT | SCSI_SCAN_LUN_PRESENT |
+ SCSI_SCAN_NEW_LUN);
}
/**
@@ -1479,11 +1530,7 @@
* Call scsi_probe_lun, if a LUN with an attached device is found,
* allocate and set it up by calling scsi_add_lun.
*
- * Return:
- * SCSI_SCAN_NO_RESPONSE: could not allocate or setup a Scsi_Device
- * SCSI_SCAN_TARGET_PRESENT: target responded, but no device is
- * attached at the LUN
- * SCSI_SCAN_LUN_PRESENT: a new Scsi_Device was allocated and initialized
+ * Returns a SCSI_SCAN_ mask value.
**/
static int scsi_probe_and_add_lun(Scsi_Device *sdevscan, Scsi_Device **sdevnew,
int *bflagsp)
@@ -1493,7 +1540,15 @@
unsigned char *scsi_result = NULL;
int bflags;
int res;
+ struct scsi_path_id pathid;
+
+ if (sdevnew != NULL)
+ *sdevnew = NULL;
+ if (scsi_get_path(sdevscan, &pathid)) {
+ printk(KERN_ERR "scsi scan: no path to scan device.\n");
+ return SCSI_SCAN_NO_RESPONSE;
+ }
/*
* Any command blocks allocated are fixed to use sdevscan->lun,
* so they must be allocated and released if sdevscan->lun
@@ -1519,9 +1574,8 @@
* The sreq is for use only with sdevscan.
*/
- scsi_result = kmalloc(256, GFP_ATOMIC |
- (sdevscan->host->unchecked_isa_dma) ?
- GFP_DMA : 0);
+ scsi_result = kmalloc(256, GFP_ATOMIC |
+ (pathid.spi_shpnt->unchecked_isa_dma) ? GFP_DMA : 0);
if (scsi_result == NULL)
goto alloc_failed;
@@ -1550,12 +1604,12 @@
} else {
res = scsi_add_lun(sdevscan, &sdev, sreq, scsi_result,
&bflags);
- if (res == SCSI_SCAN_LUN_PRESENT) {
+ if (res & SCSI_SCAN_LUN_PRESENT) {
BUG_ON(sdev == NULL);
- if ((bflags & BLIST_KEY) != 0) {
+ if ((res & SCSI_SCAN_NEW_LUN) &&
+ (bflags & BLIST_KEY) != 0) {
sdev->lockable = 0;
- scsi_unlock_floptical(sreq,
- scsi_result);
+ scsi_unlock_floptical(sreq, scsi_result);
/*
* scsi_result no longer contains
* the INQUIRY data.
@@ -1604,22 +1658,26 @@
static void scsi_sequential_lun_scan(Scsi_Device *sdevscan, int bflags,
int lun0_res)
{
- struct Scsi_Host *shost = sdevscan->host;
unsigned int sparse_lun;
unsigned int max_dev_lun;
+ struct scsi_path_id pathid;
+ if (scsi_get_path(sdevscan, &pathid)) {
+ printk(KERN_ERR "scsi scan: no path to scan device.\n");
+ return;
+ }
SCSI_LOG_SCAN_BUS(3, printk(KERN_INFO "scsi scan: Sequential scan of"
- " host %d channel %d id %d\n", sdevscan->host->host_no,
- sdevscan->channel, sdevscan->id));
+ " host %d channel %d id %d\n", pathid.spi_shpnt->host_no,
+ pathid.spi_channel, pathid.spi_id));
- max_dev_lun = min(max_scsi_luns, shost->max_lun);
+ max_dev_lun = min(max_scsi_luns, pathid.spi_shpnt->max_lun);
/*
* If this device is known to support sparse multiple units,
* override the other settings, and scan all of them. Normally,
* SCSI-3 devices should be scanned via the REPORT LUNS.
*/
if (bflags & BLIST_SPARSELUN) {
- max_dev_lun = shost->max_lun;
+ max_dev_lun = pathid.spi_shpnt->max_lun;
sparse_lun = 1;
} else
sparse_lun = 0;
@@ -1628,7 +1686,7 @@
* If not sparse lun and no device attached at LUN 0 do not scan
* any further.
*/
- if (!sparse_lun && (lun0_res != SCSI_SCAN_LUN_PRESENT))
+ if (!sparse_lun && !(lun0_res & SCSI_SCAN_LUN_PRESENT))
return;
/*
@@ -1645,7 +1703,7 @@
* the other settings, and scan all of them.
*/
if (bflags & BLIST_FORCELUN)
- max_dev_lun = shost->max_lun;
+ max_dev_lun = pathid.spi_shpnt->max_lun;
/*
* REGAL CDC-4X: avoid hang after LUN 4
*/
@@ -1663,10 +1721,16 @@
* until we reach the max, or no LUN is found and we are not
* sparse_lun.
*/
- for (sdevscan->lun = 1; sdevscan->lun < max_dev_lun; ++sdevscan->lun)
- if ((scsi_probe_and_add_lun(sdevscan, NULL, NULL)
- != SCSI_SCAN_LUN_PRESENT) && !sparse_lun)
+
+ for (pathid.spi_lun = 1; pathid.spi_lun < max_dev_lun;
+ ++pathid.spi_lun) {
+ scsi_replace_path(sdevscan, pathid.spi_shpnt,
+ pathid.spi_channel, pathid.spi_id,
+ pathid.spi_lun);
+ if (!(scsi_probe_and_add_lun(sdevscan, NULL, NULL)
+ & SCSI_SCAN_LUN_PRESENT) && !sparse_lun)
return;
+ }
}
#ifdef CONFIG_SCSI_REPORT_LUNS
@@ -1730,6 +1794,7 @@
ScsiLun *fcp_cur_lun, *lun_data;
Scsi_Request *sreq;
char *data;
+ struct scsi_path_id pathid;
/*
* Only support SCSI-3 and up devices.
@@ -1737,6 +1802,13 @@
if (sdevscan->scsi_level < SCSI_3)
return 1;
+ if (scsi_get_path(sdevscan, &pathid)) {
+ printk(KERN_ERR "scsi scan: no path to scan device.\n");
+ /*
+ * An inconsistency, so don't try scanning any further.
+ */
+ return 0;
+ }
sdevscan->new_queue_depth = 1;
scsi_build_commandblocks(sdevscan);
if (sdevscan->current_queue_depth == 0) {
@@ -1748,8 +1820,8 @@
}
sreq = scsi_allocate_request(sdevscan);
- sprintf(devname, "host %d channel %d id %d", sdevscan->host->host_no,
- sdevscan->channel, sdevscan->id);
+ sprintf(devname, "host %d channel %d id %d", pathid.spi_shpnt->host_no,
+ pathid.spi_channel, pathid.spi_id);
/*
* Allocate enough to hold the header (the same size as one ScsiLun)
* plus the max number of luns we are requesting.
@@ -1761,9 +1833,8 @@
* prevent us from finding any LUNs on this target.
*/
length = (max_scsi_report_luns + 1) * sizeof(ScsiLun);
- lun_data = (ScsiLun *) kmalloc(length, GFP_ATOMIC |
- (sdevscan->host->unchecked_isa_dma ?
- GFP_DMA : 0));
+ lun_data = (ScsiLun *) kmalloc(length, GFP_ATOMIC |
+ (pathid.spi_shpnt->unchecked_isa_dma ? GFP_DMA : 0));
if (lun_data == NULL) {
printk(ALLOC_FAILURE_MSG, __FUNCTION__);
scsi_release_commandblocks(sdevscan);
@@ -1843,9 +1914,8 @@
} else
num_luns = (length / sizeof(ScsiLun));
- SCSI_LOG_SCAN_BUS(3, printk (KERN_INFO "scsi scan: REPORT LUN scan of"
- " host %d channel %d id %d\n", sdevscan->host->host_no,
- sdevscan->channel, sdevscan->id));
+ SCSI_LOG_SCAN_BUS(3,
+ printk(KERN_INFO "scsi scan: REPORT LUN scan of %s\n", devname));
/*
* Scan the luns in lun_data. The entry at offset 0 is really
* the header, so start at 1 and go up to and including num_luns.
@@ -1875,22 +1945,23 @@
/*
* LUN 0 has already been scanned.
*/
- } else if (lun > sdevscan->host->max_lun) {
+ } else if (lun > pathid.spi_shpnt->max_lun) {
printk(KERN_WARNING "scsi: %s lun%d has a LUN larger"
" than allowed by the host adapter\n",
devname, lun);
} else {
- int res;
-
- sdevscan->lun = lun;
- res = scsi_probe_and_add_lun(sdevscan, NULL, NULL);
- if (res == SCSI_SCAN_NO_RESPONSE) {
+ pathid.spi_lun = lun;
+ scsi_replace_path(sdevscan, pathid.spi_shpnt,
+ pathid.spi_channel, pathid.spi_id,
+ pathid.spi_lun);
+ if (scsi_probe_and_add_lun(sdevscan, NULL, NULL) ==
+ SCSI_SCAN_NO_RESPONSE) {
/*
* Got some results, but now none, abort.
*/
printk(KERN_ERR "scsi: Unexpected response"
" from %s lun %d while scanning, scan"
- " aborted\n", devname, sdevscan->lun);
+ " aborted\n", devname, pathid.spi_lun);
break;
}
}
@@ -1936,18 +2007,15 @@
*/
return;
- sdevscan->host = shost;
- sdevscan->id = id;
- sdevscan->channel = channel;
+ scsi_replace_path(sdevscan, shost, channel, id, 0 /* LUN */);
/*
* Scan LUN 0, if there is some response, scan further. Ideally, we
* would not configure LUN 0 until all LUNs are scanned.
*
* The scsi_level is set (in scsi_probe_lun) if a target responds.
*/
- sdevscan->lun = 0;
res = scsi_probe_and_add_lun(sdevscan, NULL, &bflags);
- if (res != SCSI_SCAN_NO_RESPONSE) {
+ if (res & SCSI_SCAN_TARGET_PRESENT) {
/*
* Some scsi devices cannot properly handle a lun != 0.
* BLIST_NOLUN also prevents a REPORT LUN from being sent.
@@ -1993,11 +2061,11 @@
return;
sdevscan->scsi_level = scsi_find_scsi_level(channel, id, shost);
+ sdevscan->scanning = 1;
res = scsi_probe_and_add_lun(sdevscan, &sdev, NULL);
- scsi_free_sdev(sdevscan);
- if (res == SCSI_SCAN_LUN_PRESENT) {
+ scsi_remove_scsi_device(sdevscan);
+ if (res & SCSI_SCAN_NEW_LUN) {
BUG_ON(sdev == NULL);
-
for (sdt = scsi_devicelist; sdt; sdt = sdt->next)
if (sdt->init && sdt->dev_noticed)
(*sdt->init) ();
@@ -2063,12 +2131,20 @@
* queue_nr_requests requests are allocated. Don't do so
* here for scsi_scan_selected_lun, since we end up
* calling select_queue_depths with an extra Scsi_Device
- * on the host_queue list.
+ * on the device list.
*/
sdevscan = scsi_alloc_sdev(shost, 0, 0, 0);
if (sdevscan == NULL)
return;
/*
+ * Set the scanning bit, so error messages about errors
+ * and path failure are not printed; this should be used
+ * in scsi_error.c to prevent overly aggressive action on
+ * failure for a scan. This is never reset, as the default
+ * state for a new Scsi_Device is 0.
+ */
+ sdevscan->scanning = 1;
+ /*
* The sdevscan host, channel, id and lun are filled in as
* needed to scan.
*/
@@ -2094,6 +2170,6 @@
order_id);
}
}
- scsi_free_sdev(sdevscan);
+ scsi_remove_scsi_device(sdevscan);
}
}
diff -Nru a/drivers/scsi/scsi_syms.c b/drivers/scsi/scsi_syms.c
--- a/drivers/scsi/scsi_syms.c Fri Oct 25 11:26:47 2002
+++ b/drivers/scsi/scsi_syms.c Fri Oct 25 11:26:47 2002
@@ -71,6 +71,7 @@
EXPORT_SYMBOL(scsi_get_host_dev);
EXPORT_SYMBOL(scsi_free_host_dev);
+EXPORT_SYMBOL(scsi_sdev_list);
EXPORT_SYMBOL(scsi_sleep);
@@ -105,6 +106,12 @@
EXPORT_SYMBOL(scsi_add_timer);
EXPORT_SYMBOL(scsi_delete_timer);
+EXPORT_SYMBOL(scsi_add_path);
+EXPORT_SYMBOL(scsi_remove_path);
+EXPORT_SYMBOL(scsi_get_path);
+EXPORT_SYMBOL(scsi_get_host);
+EXPORT_SYMBOL(scsi_paths_printk);
+EXPORT_SYMBOL(scsi_traverse_sdevs);
/*
* driverfs support for determining driver types
*/
diff -Nru a/include/scsi/scsi.h b/include/scsi/scsi.h
--- a/include/scsi/scsi.h Fri Oct 25 11:26:48 2002
+++ b/include/scsi/scsi.h Fri Oct 25 11:26:48 2002
@@ -91,6 +91,29 @@
#define WRITE_LONG_2 0xea
/*
+ * SCSI INQUIRY Flags (byte 7)
+ */
+#define SCSI_EVPD 0x01 /* enable vital product data */
+#define SCSI_RMB7 0x80 /* removable media */
+#define SCSI_AENC 0x80 /* asynchronous event notification capability */
+#define SCSI_TRMIOP 0x40 /* terminate I/O process capability */
+#define SCSI_RELADR7 0x80 /* relative addressing capability */
+#define SCSI_WBUS16 0x20 /* 16 byte wide transfer capabilitiy */
+#define SCSI_WBUS32 0x40 /* 32 byte wide transfer capabilitiy */
+#define SCSI_SYNC 0x10 /* synchronous data transfer capability */
+#define SCSI_LINKED 0x08 /* linked command capability */
+#define SCSI_CMDQUE 0x02 /* command queueing capability */
+#define SCSI_SFTRE 0x01 /* soft reset capability */
+
+/*
+ * SCSI INQUIRY Vital Product Data Page Codes
+ */
+#define SCSI_VPROD_SUPPORTED 0x00
+#define SCSI_VPROD_UNIT_SERIAL 0x80
+#define SCSI_VPROD_AODEFN 0x82
+#define SCSI_VPROD_DEVICE_ID 0x83
+
+/*
* Status codes
*/
-
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This archive was generated by hypermail 2b29 : Thu Oct 31 2002 - 22:00:29 EST