linux-stable/drivers/scsi/cxlflash/lunmgt.c
Matthew R. Ochs 8fa4f1770d scsi: cxlflash: Remove port configuration assumptions
At present, the cxlflash driver only supports hardware with two FC ports. The
code was initially designed with this assumption and is dependent on having
two FC ports - adding more ports will break logic within the driver.

To mitigate this issue, remove the existing port assumptions and transition
the code to support more than two ports. As a side effect, clarify the
interpretation of the DK_CXLFLASH_ALL_PORTS_ACTIVE flag.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-04-13 22:55:41 -04:00

280 lines
7.4 KiB
C

/*
* CXL Flash Device Driver
*
* Written by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>, IBM Corporation
* Matthew R. Ochs <mrochs@linux.vnet.ibm.com>, IBM Corporation
*
* Copyright (C) 2015 IBM Corporation
*
* 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.
*/
#include <misc/cxl.h>
#include <asm/unaligned.h>
#include <scsi/scsi_host.h>
#include <uapi/scsi/cxlflash_ioctl.h>
#include "sislite.h"
#include "common.h"
#include "vlun.h"
#include "superpipe.h"
/**
* create_local() - allocate and initialize a local LUN information structure
* @sdev: SCSI device associated with LUN.
* @wwid: World Wide Node Name for LUN.
*
* Return: Allocated local llun_info structure on success, NULL on failure
*/
static struct llun_info *create_local(struct scsi_device *sdev, u8 *wwid)
{
struct cxlflash_cfg *cfg = shost_priv(sdev->host);
struct device *dev = &cfg->dev->dev;
struct llun_info *lli = NULL;
lli = kzalloc(sizeof(*lli), GFP_KERNEL);
if (unlikely(!lli)) {
dev_err(dev, "%s: could not allocate lli\n", __func__);
goto out;
}
lli->sdev = sdev;
lli->host_no = sdev->host->host_no;
lli->in_table = false;
memcpy(lli->wwid, wwid, DK_CXLFLASH_MANAGE_LUN_WWID_LEN);
out:
return lli;
}
/**
* create_global() - allocate and initialize a global LUN information structure
* @sdev: SCSI device associated with LUN.
* @wwid: World Wide Node Name for LUN.
*
* Return: Allocated global glun_info structure on success, NULL on failure
*/
static struct glun_info *create_global(struct scsi_device *sdev, u8 *wwid)
{
struct cxlflash_cfg *cfg = shost_priv(sdev->host);
struct device *dev = &cfg->dev->dev;
struct glun_info *gli = NULL;
gli = kzalloc(sizeof(*gli), GFP_KERNEL);
if (unlikely(!gli)) {
dev_err(dev, "%s: could not allocate gli\n", __func__);
goto out;
}
mutex_init(&gli->mutex);
memcpy(gli->wwid, wwid, DK_CXLFLASH_MANAGE_LUN_WWID_LEN);
out:
return gli;
}
/**
* lookup_local() - find a local LUN information structure by WWID
* @cfg: Internal structure associated with the host.
* @wwid: WWID associated with LUN.
*
* Return: Found local lun_info structure on success, NULL on failure
*/
static struct llun_info *lookup_local(struct cxlflash_cfg *cfg, u8 *wwid)
{
struct llun_info *lli, *temp;
list_for_each_entry_safe(lli, temp, &cfg->lluns, list)
if (!memcmp(lli->wwid, wwid, DK_CXLFLASH_MANAGE_LUN_WWID_LEN))
return lli;
return NULL;
}
/**
* lookup_global() - find a global LUN information structure by WWID
* @wwid: WWID associated with LUN.
*
* Return: Found global lun_info structure on success, NULL on failure
*/
static struct glun_info *lookup_global(u8 *wwid)
{
struct glun_info *gli, *temp;
list_for_each_entry_safe(gli, temp, &global.gluns, list)
if (!memcmp(gli->wwid, wwid, DK_CXLFLASH_MANAGE_LUN_WWID_LEN))
return gli;
return NULL;
}
/**
* find_and_create_lun() - find or create a local LUN information structure
* @sdev: SCSI device associated with LUN.
* @wwid: WWID associated with LUN.
*
* The LUN is kept both in a local list (per adapter) and in a global list
* (across all adapters). Certain attributes of the LUN are local to the
* adapter (such as index, port selection mask, etc.).
*
* The block allocation map is shared across all adapters (i.e. associated
* wih the global list). Since different attributes are associated with
* the per adapter and global entries, allocate two separate structures for each
* LUN (one local, one global).
*
* Keep a pointer back from the local to the global entry.
*
* This routine assumes the caller holds the global mutex.
*
* Return: Found/Allocated local lun_info structure on success, NULL on failure
*/
static struct llun_info *find_and_create_lun(struct scsi_device *sdev, u8 *wwid)
{
struct cxlflash_cfg *cfg = shost_priv(sdev->host);
struct device *dev = &cfg->dev->dev;
struct llun_info *lli = NULL;
struct glun_info *gli = NULL;
if (unlikely(!wwid))
goto out;
lli = lookup_local(cfg, wwid);
if (lli)
goto out;
lli = create_local(sdev, wwid);
if (unlikely(!lli))
goto out;
gli = lookup_global(wwid);
if (gli) {
lli->parent = gli;
list_add(&lli->list, &cfg->lluns);
goto out;
}
gli = create_global(sdev, wwid);
if (unlikely(!gli)) {
kfree(lli);
lli = NULL;
goto out;
}
lli->parent = gli;
list_add(&lli->list, &cfg->lluns);
list_add(&gli->list, &global.gluns);
out:
dev_dbg(dev, "%s: returning lli=%p, gli=%p\n", __func__, lli, gli);
return lli;
}
/**
* cxlflash_term_local_luns() - Delete all entries from local LUN list, free.
* @cfg: Internal structure associated with the host.
*/
void cxlflash_term_local_luns(struct cxlflash_cfg *cfg)
{
struct llun_info *lli, *temp;
mutex_lock(&global.mutex);
list_for_each_entry_safe(lli, temp, &cfg->lluns, list) {
list_del(&lli->list);
kfree(lli);
}
mutex_unlock(&global.mutex);
}
/**
* cxlflash_list_init() - initializes the global LUN list
*/
void cxlflash_list_init(void)
{
INIT_LIST_HEAD(&global.gluns);
mutex_init(&global.mutex);
global.err_page = NULL;
}
/**
* cxlflash_term_global_luns() - frees resources associated with global LUN list
*/
void cxlflash_term_global_luns(void)
{
struct glun_info *gli, *temp;
mutex_lock(&global.mutex);
list_for_each_entry_safe(gli, temp, &global.gluns, list) {
list_del(&gli->list);
cxlflash_ba_terminate(&gli->blka.ba_lun);
kfree(gli);
}
mutex_unlock(&global.mutex);
}
/**
* cxlflash_manage_lun() - handles LUN management activities
* @sdev: SCSI device associated with LUN.
* @manage: Manage ioctl data structure.
*
* This routine is used to notify the driver about a LUN's WWID and associate
* SCSI devices (sdev) with a global LUN instance. Additionally it serves to
* change a LUN's operating mode: legacy or superpipe.
*
* Return: 0 on success, -errno on failure
*/
int cxlflash_manage_lun(struct scsi_device *sdev,
struct dk_cxlflash_manage_lun *manage)
{
struct cxlflash_cfg *cfg = shost_priv(sdev->host);
struct device *dev = &cfg->dev->dev;
struct llun_info *lli = NULL;
int rc = 0;
u64 flags = manage->hdr.flags;
u32 chan = sdev->channel;
mutex_lock(&global.mutex);
lli = find_and_create_lun(sdev, manage->wwid);
dev_dbg(dev, "%s: WWID=%016llx%016llx, flags=%016llx lli=%p\n",
__func__, get_unaligned_be64(&manage->wwid[0]),
get_unaligned_be64(&manage->wwid[8]), manage->hdr.flags, lli);
if (unlikely(!lli)) {
rc = -ENOMEM;
goto out;
}
if (flags & DK_CXLFLASH_MANAGE_LUN_ENABLE_SUPERPIPE) {
/*
* Update port selection mask based upon channel, store off LUN
* in unpacked, AFU-friendly format, and hang LUN reference in
* the sdev.
*/
lli->port_sel |= CHAN2PORTMASK(chan);
lli->lun_id[chan] = lun_to_lunid(sdev->lun);
sdev->hostdata = lli;
} else if (flags & DK_CXLFLASH_MANAGE_LUN_DISABLE_SUPERPIPE) {
if (lli->parent->mode != MODE_NONE)
rc = -EBUSY;
else {
/*
* Clean up local LUN for this port and reset table
* tracking when no more references exist.
*/
sdev->hostdata = NULL;
lli->port_sel &= ~CHAN2PORTMASK(chan);
if (lli->port_sel == 0U)
lli->in_table = false;
}
}
dev_dbg(dev, "%s: port_sel=%08x chan=%u lun_id=%016llx\n",
__func__, lli->port_sel, chan, lli->lun_id[chan]);
out:
mutex_unlock(&global.mutex);
dev_dbg(dev, "%s: returning rc=%d\n", __func__, rc);
return rc;
}