drivers/scsi/cxlflash/lunmgt.c - kernel/quantenna - Git at Google

 /*
  * 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 llun_info *lli = NULL;

 	lli = kzalloc(sizeof(*lli), GFP_KERNEL);
 	if (unlikely(!lli)) {
 		pr_err("%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 glun_info *gli = NULL;

 	gli = kzalloc(sizeof(*gli), GFP_KERNEL);
 	if (unlikely(!gli)) {
 		pr_err("%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 llun_info *lli = NULL;
 	struct glun_info *gli = NULL;
 	struct Scsi_Host *shost = sdev->host;
 	struct cxlflash_cfg *cfg = shost_priv(shost);

 	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:
 	pr_debug("%s: returning %p\n", __func__, lli);
 	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)
 {
 	int rc = 0;
 	struct llun_info *lli = NULL;
 	u64 flags = manage->hdr.flags;
 	u32 chan = sdev->channel;

 	mutex_lock(&global.mutex);
 	lli = find_and_create_lun(sdev, manage->wwid);
 	pr_debug("%s: ENTER: WWID = %016llX%016llX, flags = %016llX li = %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 |= CHAN2PORT(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 {
 			sdev->hostdata = NULL;
 			lli->port_sel &= ~CHAN2PORT(chan);
 		}
 	}

 	pr_debug("%s: port_sel = %08X chan = %u lun_id = %016llX\n", __func__,
 		 lli->port_sel, chan, lli->lun_id[chan]);

 out:
 	mutex_unlock(&global.mutex);
 	pr_debug("%s: returning rc=%d\n", __func__, rc);
 	return rc;
 }
	/*
	* 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 llun_info *lli = NULL;

	lli = kzalloc(sizeof(*lli), GFP_KERNEL);
	if (unlikely(!lli)) {
	pr_err("%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 glun_info *gli = NULL;

	gli = kzalloc(sizeof(*gli), GFP_KERNEL);
	if (unlikely(!gli)) {
	pr_err("%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 llun_info *lli = NULL;
	struct glun_info *gli = NULL;
	struct Scsi_Host *shost = sdev->host;
	struct cxlflash_cfg *cfg = shost_priv(shost);

	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:
	pr_debug("%s: returning %p\n", __func__, lli);
	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)
	{
	int rc = 0;
	struct llun_info *lli = NULL;
	u64 flags = manage->hdr.flags;
	u32 chan = sdev->channel;

	mutex_lock(&global.mutex);
	lli = find_and_create_lun(sdev, manage->wwid);
	pr_debug("%s: ENTER: WWID = %016llX%016llX, flags = %016llX li = %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 \|= CHAN2PORT(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 {
	sdev->hostdata = NULL;
	lli->port_sel &= ~CHAN2PORT(chan);
	}
	}

	pr_debug("%s: port_sel = %08X chan = %u lun_id = %016llX\n", __func__,
	lli->port_sel, chan, lli->lun_id[chan]);

	out:
	mutex_unlock(&global.mutex);
	pr_debug("%s: returning rc=%d\n", __func__, rc);
	return rc;
	}