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cxlflash: Superpipe support 

Add superpipe supporting infrastructure to device driver for the IBM CXL
Flash adapter. This patch allows userspace applications to take advantage
of the accelerated I/O features that this adapter provides and bypass the
traditional filesystem stack.

Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>
Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com>
Reviewed-by: Michael Neuling <mikey@neuling.org>
Reviewed-by: Wen Xiong <wenxiong@linux.vnet.ibm.com>
Reviewed-by: Brian King <brking@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
hifive-unleashed-5.1
Matthew R. Ochs 2015-08-13 21:47:43 -05:00 committed by James Bottomley
parent 5cdac81a87
commit 65be2c79ac
11 changed files with 2868 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
Documentation/ioctl/ioctl-number.txt
View File

@ -314,6 +314,7 @@ Code Seq#(hex) Include File Comments
0xB3 00 linux/mmc/ioctl.h
0xC0 00-0F linux/usb/iowarrior.h
0xCA 00-0F uapi/misc/cxl.h
0xCA 80-8F uapi/scsi/cxlflash_ioctl.h
0xCB 00-1F CBM serial IEC bus in development:
<mailto:michael.klein@puffin.lb.shuttle.de>
0xCD 01 linux/reiserfs_fs.h

257
Documentation/powerpc/cxlflash.txt 100644
View File

@ -0,0 +1,257 @@
Introduction
============
The IBM Power architecture provides support for CAPI (Coherent
Accelerator Power Interface), which is available to certain PCIe slots
on Power 8 systems. CAPI can be thought of as a special tunneling
protocol through PCIe that allow PCIe adapters to look like special
purpose co-processors which can read or write an application's
memory and generate page faults. As a result, the host interface to
an adapter running in CAPI mode does not require the data buffers to
be mapped to the device's memory (IOMMU bypass) nor does it require
memory to be pinned.
On Linux, Coherent Accelerator (CXL) kernel services present CAPI
devices as a PCI device by implementing a virtual PCI host bridge.
This abstraction simplifies the infrastructure and programming
model, allowing for drivers to look similar to other native PCI
device drivers.
CXL provides a mechanism by which user space applications can
directly talk to a device (network or storage) bypassing the typical
kernel/device driver stack. The CXL Flash Adapter Driver enables a
user space application direct access to Flash storage.
The CXL Flash Adapter Driver is a kernel module that sits in the
SCSI stack as a low level device driver (below the SCSI disk and
protocol drivers) for the IBM CXL Flash Adapter. This driver is
responsible for the initialization of the adapter, setting up the
special path for user space access, and performing error recovery. It
communicates directly the Flash Accelerator Functional Unit (AFU)
as described in Documentation/powerpc/cxl.txt.
The cxlflash driver supports two, mutually exclusive, modes of
operation at the device (LUN) level:
- Any flash device (LUN) can be configured to be accessed as a
regular disk device (i.e.: /dev/sdc). This is the default mode.
- Any flash device (LUN) can be configured to be accessed from
user space with a special block library. This mode further
specifies the means of accessing the device and provides for
either raw access to the entire LUN (referred to as direct
or physical LUN access) or access to a kernel/AFU-mediated
partition of the LUN (referred to as virtual LUN access). The
segmentation of a disk device into virtual LUNs is assisted
by special translation services provided by the Flash AFU.
Overview
========
The Coherent Accelerator Interface Architecture (CAIA) introduces a
concept of a master context. A master typically has special privileges
granted to it by the kernel or hypervisor allowing it to perform AFU
wide management and control. The master may or may not be involved
directly in each user I/O, but at the minimum is involved in the
initial setup before the user application is allowed to send requests
directly to the AFU.
The CXL Flash Adapter Driver establishes a master context with the
AFU. It uses memory mapped I/O (MMIO) for this control and setup. The
Adapter Problem Space Memory Map looks like this:
+-------------------------------+
| 512 * 64 KB User MMIO |
| (per context) |
| User Accessible |
+-------------------------------+
| 512 * 128 B per context |
| Provisioning and Control |
| Trusted Process accessible |
+-------------------------------+
| 64 KB Global |
| Trusted Process accessible |
+-------------------------------+
This driver configures itself into the SCSI software stack as an
adapter driver. The driver is the only entity that is considered a
Trusted Process to program the Provisioning and Control and Global
areas in the MMIO Space shown above. The master context driver
discovers all LUNs attached to the CXL Flash adapter and instantiates
scsi block devices (/dev/sdb, /dev/sdc etc.) for each unique LUN
seen from each path.
Once these scsi block devices are instantiated, an application
written to a specification provided by the block library may get
access to the Flash from user space (without requiring a system call).
This master context driver also provides a series of ioctls for this
block library to enable this user space access. The driver supports
two modes for accessing the block device.
The first mode is called a virtual mode. In this mode a single scsi
block device (/dev/sdb) may be carved up into any number of distinct
virtual LUNs. The virtual LUNs may be resized as long as the sum of
the sizes of all the virtual LUNs, along with the meta-data associated
with it does not exceed the physical capacity.
The second mode is called the physical mode. In this mode a single
block device (/dev/sdb) may be opened directly by the block library
and the entire space for the LUN is available to the application.
Only the physical mode provides persistence of the data. i.e. The
data written to the block device will survive application exit and
restart and also reboot. The virtual LUNs do not persist (i.e. do
not survive after the application terminates or the system reboots).
Block library API
=================
Applications intending to get access to the CXL Flash from user
space should use the block library, as it abstracts the details of
interfacing directly with the cxlflash driver that are necessary for
performing administrative actions (i.e.: setup, tear down, resize).
The block library can be thought of as a 'user' of services,
implemented as IOCTLs, that are provided by the cxlflash driver
specifically for devices (LUNs) operating in user space access
mode. While it is not a requirement that applications understand
the interface between the block library and the cxlflash driver,
a high-level overview of each supported service (IOCTL) is provided
below.
The block library can be found on GitHub:
http://www.github.com/mikehollinger/ibmcapikv
CXL Flash Driver IOCTLs
=======================
Users, such as the block library, that wish to interface with a flash
device (LUN) via user space access need to use the services provided
by the cxlflash driver. As these services are implemented as ioctls,
a file descriptor handle must first be obtained in order to establish
the communication channel between a user and the kernel. This file
descriptor is obtained by opening the device special file associated
with the scsi disk device (/dev/sdb) that was created during LUN
discovery. As per the location of the cxlflash driver within the
SCSI protocol stack, this open is actually not seen by the cxlflash
driver. Upon successful open, the user receives a file descriptor
(herein referred to as fd1) that should be used for issuing the
subsequent ioctls listed below.
The structure definitions for these IOCTLs are available in:
uapi/scsi/cxlflash_ioctl.h
DK_CXLFLASH_ATTACH
------------------
This ioctl obtains, initializes, and starts a context using the CXL
kernel services. These services specify a context id (u16) by which
to uniquely identify the context and its allocated resources. The
services additionally provide a second file descriptor (herein
referred to as fd2) that is used by the block library to initiate
memory mapped I/O (via mmap()) to the CXL flash device and poll for
completion events. This file descriptor is intentionally installed by
this driver and not the CXL kernel services to allow for intermediary
notification and access in the event of a non-user-initiated close(),
such as a killed process. This design point is described in further
detail in the description for the DK_CXLFLASH_DETACH ioctl.
There are a few important aspects regarding the "tokens" (context id
and fd2) that are provided back to the user:
- These tokens are only valid for the process under which they
were created. The child of a forked process cannot continue
to use the context id or file descriptor created by its parent.
- These tokens are only valid for the lifetime of the context and
the process under which they were created. Once either is
destroyed, the tokens are to be considered stale and subsequent
usage will result in errors.
- When a context is no longer needed, the user shall detach from
the context via the DK_CXLFLASH_DETACH ioctl.
- A close on fd2 will invalidate the tokens. This operation is not
required by the user.
DK_CXLFLASH_USER_DIRECT
-----------------------
This ioctl is responsible for transitioning the LUN to direct
(physical) mode access and configuring the AFU for direct access from
user space on a per-context basis. Additionally, the block size and
last logical block address (LBA) are returned to the user.
As mentioned previously, when operating in user space access mode,
LUNs may be accessed in whole or in part. Only one mode is allowed
at a time and if one mode is active (outstanding references exist),
requests to use the LUN in a different mode are denied.
The AFU is configured for direct access from user space by adding an
entry to the AFU's resource handle table. The index of the entry is
treated as a resource handle that is returned to the user. The user
is then able to use the handle to reference the LUN during I/O.
DK_CXLFLASH_RELEASE
-------------------
This ioctl is responsible for releasing a previously obtained
reference to either a physical or virtual LUN. This can be
thought of as the inverse of the DK_CXLFLASH_USER_DIRECT or
DK_CXLFLASH_USER_VIRTUAL ioctls. Upon success, the resource handle
is no longer valid and the entry in the resource handle table is
made available to be used again.
As part of the release process for virtual LUNs, the virtual LUN
is first resized to 0 to clear out and free the translation tables
associated with the virtual LUN reference.
DK_CXLFLASH_DETACH
------------------
This ioctl is responsible for unregistering a context with the
cxlflash driver and release outstanding resources that were
not explicitly released via the DK_CXLFLASH_RELEASE ioctl. Upon
success, all "tokens" which had been provided to the user from the
DK_CXLFLASH_ATTACH onward are no longer valid.
DK_CXLFLASH_VERIFY
------------------
This ioctl is used to detect various changes such as the capacity of
the disk changing, the number of LUNs visible changing, etc. In cases
where the changes affect the application (such as a LUN resize), the
cxlflash driver will report the changed state to the application.
The user calls in when they want to validate that a LUN hasn't been
changed in response to a check condition. As the user is operating out
of band from the kernel, they will see these types of events without
the kernel's knowledge. When encountered, the user's architected
behavior is to call in to this ioctl, indicating what they want to
verify and passing along any appropriate information. For now, only
verifying a LUN change (ie: size different) with sense data is
supported.
DK_CXLFLASH_RECOVER_AFU
-----------------------
This ioctl is used to drive recovery (if such an action is warranted)
of a specified user context. Any state associated with the user context
is re-established upon successful recovery.
User contexts are put into an error condition when the device needs to
be reset or is terminating. Users are notified of this error condition
by seeing all 0xF's on an MMIO read. Upon encountering this, the
architected behavior for a user is to call into this ioctl to recover
their context. A user may also call into this ioctl at any time to
check if the device is operating normally. If a failure is returned
from this ioctl, the user is expected to gracefully clean up their
context via release/detach ioctls. Until they do, the context they
hold is not relinquished. The user may also optionally exit the process
at which time the context/resources they held will be freed as part of
the release fop.
DK_CXLFLASH_MANAGE_LUN
----------------------
This ioctl is used to switch a LUN from a mode where it is available
for file-system access (legacy), to a mode where it is set aside for
exclusive user space access (superpipe). In case a LUN is visible
across multiple ports and adapters, this ioctl is used to uniquely
identify each LUN by its World Wide Node Name (WWNN).

2
drivers/scsi/cxlflash/Makefile
View File

@ -1,2 +1,2 @@
obj-$(CONFIG_CXLFLASH) += cxlflash.o
cxlflash-y += main.o
cxlflash-y += main.o superpipe.o lunmgt.o

19
drivers/scsi/cxlflash/common.h
View File

@ -107,6 +107,17 @@ struct cxlflash_cfg {
struct pci_pool *cxlflash_cmd_pool;
struct pci_dev *parent_dev;
atomic_t recovery_threads;
struct mutex ctx_recovery_mutex;
struct mutex ctx_tbl_list_mutex;
struct ctx_info *ctx_tbl[MAX_CONTEXT];
struct list_head ctx_err_recovery; /* contexts w/ recovery pending */
struct file_operations cxl_fops;
atomic_t num_user_contexts;
struct list_head lluns; /* list of llun_info structs */
wait_queue_head_t tmf_waitq;
bool tmf_active;
wait_queue_head_t limbo_waitq;
@ -182,4 +193,12 @@ int cxlflash_afu_reset(struct cxlflash_cfg *);
struct afu_cmd *cxlflash_cmd_checkout(struct afu *);
void cxlflash_cmd_checkin(struct afu_cmd *);
int cxlflash_afu_sync(struct afu *, ctx_hndl_t, res_hndl_t, u8);
void cxlflash_list_init(void);
void cxlflash_term_global_luns(void);
void cxlflash_free_errpage(void);
int cxlflash_ioctl(struct scsi_device *, int, void __user *);
void cxlflash_stop_term_user_contexts(struct cxlflash_cfg *);
int cxlflash_mark_contexts_error(struct cxlflash_cfg *);
void cxlflash_term_local_luns(struct cxlflash_cfg *);
#endif /* ifndef _CXLFLASH_COMMON_H */

263
drivers/scsi/cxlflash/lunmgt.c 100644
View File

@ -0,0 +1,263 @@
/*
* 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 "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->newly_created = true;
lli->host_no = sdev->host->host_no;
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;
}
/**
* refresh_local() - find and update local LUN information structure by WWID
* @cfg: Internal structure associated with the host.
* @wwid: WWID associated with LUN.
*
* When the LUN is found, mark it by updating it's newly_created field.
*
* Return: Found local lun_info structure on success, NULL on failure
* If a LUN with the WWID is found in the list, refresh it's state.
*/
static struct llun_info *refresh_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)) {
lli->newly_created = false;
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.
*
* 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);
mutex_lock(&global.mutex);
if (unlikely(!wwid))
goto out;
lli = refresh_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:
mutex_unlock(&global.mutex);
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);
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;
lli = find_and_create_lun(sdev, manage->wwid);
pr_debug("%s: ENTER: WWID = %016llX%016llX, flags = %016llX li = %p\n",
__func__, get_unaligned_le64(&manage->wwid[0]),
get_unaligned_le64(&manage->wwid[8]),
manage->hdr.flags, lli);
if (unlikely(!lli)) {
rc = -ENOMEM;
goto out;
}
if (flags & DK_CXLFLASH_MANAGE_LUN_ENABLE_SUPERPIPE) {
if (lli->newly_created)
lli->port_sel = CHAN2PORT(chan);
else
lli->port_sel = BOTH_PORTS;
/* Store off lun in unpacked, AFU-friendly format */
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;
}
out:
pr_debug("%s: returning rc=%d\n", __func__, rc);
return rc;
}

38
drivers/scsi/cxlflash/main.c
View File

@ -23,6 +23,7 @@
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_host.h>
#include <uapi/scsi/cxlflash_ioctl.h>
#include "main.h"
#include "sislite.h"
@ -519,7 +520,7 @@ static int cxlflash_eh_host_reset_handler(struct scsi_cmnd *scp)
case STATE_NORMAL:
cfg->state = STATE_LIMBO;
scsi_block_requests(cfg->host);
cxlflash_mark_contexts_error(cfg);
rcr = cxlflash_afu_reset(cfg);
if (rcr) {
rc = FAILED;
@ -662,6 +663,21 @@ static ssize_t cxlflash_store_lun_mode(struct device *dev,
return count;
}
/**
* cxlflash_show_ioctl_version() - presents the current ioctl version of the host
* @dev: Generic device associated with the host.
* @attr: Device attribute representing the ioctl version.
* @buf: Buffer of length PAGE_SIZE to report back the ioctl version.
*
* Return: The size of the ASCII string returned in @buf.
*/
static ssize_t cxlflash_show_ioctl_version(struct device *dev,
struct device_attribute *attr,
char *buf)
{
return scnprintf(buf, PAGE_SIZE, "%u\n", DK_CXLFLASH_VERSION_0);
}
/**
* cxlflash_show_dev_mode() - presents the current mode of the device
* @dev: Generic device associated with the device.
@ -700,11 +716,13 @@ static DEVICE_ATTR(port0, S_IRUGO, cxlflash_show_port_status, NULL);
static DEVICE_ATTR(port1, S_IRUGO, cxlflash_show_port_status, NULL);
static DEVICE_ATTR(lun_mode, S_IRUGO | S_IWUSR, cxlflash_show_lun_mode,
cxlflash_store_lun_mode);
static DEVICE_ATTR(ioctl_version, S_IRUGO, cxlflash_show_ioctl_version, NULL);
static struct device_attribute *cxlflash_host_attrs[] = {
&dev_attr_port0,
&dev_attr_port1,
&dev_attr_lun_mode,
&dev_attr_ioctl_version,
NULL
};
@ -725,6 +743,7 @@ static struct scsi_host_template driver_template = {
.module = THIS_MODULE,
.name = CXLFLASH_ADAPTER_NAME,
.info = cxlflash_driver_info,
.ioctl = cxlflash_ioctl,
.proc_name = CXLFLASH_NAME,
.queuecommand = cxlflash_queuecommand,
.eh_device_reset_handler = cxlflash_eh_device_reset_handler,
@ -872,9 +891,11 @@ static void cxlflash_remove(struct pci_dev *pdev)
spin_unlock_irqrestore(&cfg->tmf_waitq.lock, lock_flags);
cfg->state = STATE_FAILTERM;
cxlflash_stop_term_user_contexts(cfg);
switch (cfg->init_state) {
case INIT_STATE_SCSI:
cxlflash_term_local_luns(cfg);
scsi_remove_host(cfg->host);
scsi_host_put(cfg->host);
/* Fall through */
@ -2274,6 +2295,10 @@ static int cxlflash_probe(struct pci_dev *pdev,
INIT_WORK(&cfg->work_q, cxlflash_worker_thread);
cfg->lr_state = LINK_RESET_INVALID;
cfg->lr_port = -1;
mutex_init(&cfg->ctx_tbl_list_mutex);
mutex_init(&cfg->ctx_recovery_mutex);
INIT_LIST_HEAD(&cfg->ctx_err_recovery);
INIT_LIST_HEAD(&cfg->lluns);
pci_set_drvdata(pdev, cfg);
@ -2335,6 +2360,7 @@ out_remove:
static pci_ers_result_t cxlflash_pci_error_detected(struct pci_dev *pdev,
pci_channel_state_t state)
{
int rc = 0;
struct cxlflash_cfg *cfg = pci_get_drvdata(pdev);
struct device *dev = &cfg->dev->dev;
@ -2346,7 +2372,10 @@ static pci_ers_result_t cxlflash_pci_error_detected(struct pci_dev *pdev,
/* Turn off legacy I/O */
scsi_block_requests(cfg->host);
rc = cxlflash_mark_contexts_error(cfg);
if (unlikely(rc))
dev_err(dev, "%s: Failed to mark user contexts!(%d)\n",
__func__, rc);
term_mc(cfg, UNDO_START);
stop_afu(cfg);
@ -2431,6 +2460,8 @@ static int __init init_cxlflash(void)
pr_info("%s: IBM Power CXL Flash Adapter: %s\n",
__func__, CXLFLASH_DRIVER_DATE);
cxlflash_list_init();
return pci_register_driver(&cxlflash_driver);
}
@ -2439,6 +2470,9 @@ static int __init init_cxlflash(void)
*/
static void __exit exit_cxlflash(void)
{
cxlflash_term_global_luns();
cxlflash_free_errpage();
pci_unregister_driver(&cxlflash_driver);
}

5
drivers/scsi/cxlflash/sislite.h
View File

@ -409,7 +409,10 @@ struct sisl_lxt_entry {
};
/* Per the SISlite spec, RHT entries are to be 16-byte aligned */
/*
* RHT - Resource Handle Table
* Per the SISlite spec, RHT entries are to be 16-byte aligned
*/
struct sisl_rht_entry {
struct sisl_lxt_entry *lxt_start;
u32 lxt_cnt;

2014
drivers/scsi/cxlflash/superpipe.c 100644
View File

File diff suppressed because it is too large Load Diff

132
drivers/scsi/cxlflash/superpipe.h 100644
View File

@ -0,0 +1,132 @@
/*
* 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.
*/
#ifndef _CXLFLASH_SUPERPIPE_H
#define _CXLFLASH_SUPERPIPE_H
extern struct cxlflash_global global;
/*
* Terminology: use afu (and not adapter) to refer to the HW.
* Adapter is the entire slot and includes PSL out of which
* only the AFU is visible to user space.
*/
/* Chunk size parms: note sislite minimum chunk size is
0x10000 LBAs corresponding to a NMASK or 16.
*/
#define MC_CHUNK_SIZE (1 << MC_RHT_NMASK) /* in LBAs */
#define MC_DISCOVERY_TIMEOUT 5 /* 5 secs */
#define CHAN2PORT(_x) ((_x) + 1)
enum lun_mode {
MODE_NONE = 0,
MODE_PHYSICAL
};
/* Global (entire driver, spans adapters) lun_info structure */
struct glun_info {
u64 max_lba; /* from read cap(16) */
u32 blk_len; /* from read cap(16) */
enum lun_mode mode; /* NONE, PHYSICAL */
int users; /* Number of users w/ references to LUN */
u8 wwid[16];
struct mutex mutex;
struct list_head list;
};
/* Local (per-adapter) lun_info structure */
struct llun_info {
u64 lun_id[CXLFLASH_NUM_FC_PORTS]; /* from REPORT_LUNS */
u32 lun_index; /* Index in the LUN table */
u32 host_no; /* host_no from Scsi_host */
u32 port_sel; /* What port to use for this LUN */
bool newly_created; /* Whether the LUN was just discovered */
u8 wwid[16]; /* Keep a duplicate copy here? */
struct glun_info *parent; /* Pointer to entry in global LUN structure */
struct scsi_device *sdev;
struct list_head list;
};
struct lun_access {
struct llun_info *lli;
struct scsi_device *sdev;
struct list_head list;
};
enum ctx_ctrl {
CTX_CTRL_CLONE = (1 << 1),
CTX_CTRL_ERR = (1 << 2),
CTX_CTRL_ERR_FALLBACK = (1 << 3),
CTX_CTRL_NOPID = (1 << 4),
CTX_CTRL_FILE = (1 << 5)
};
#define ENCODE_CTXID(_ctx, _id) (((((u64)_ctx) & 0xFFFFFFFF0) << 28) | _id)
#define DECODE_CTXID(_val) (_val & 0xFFFFFFFF)
struct ctx_info {
struct sisl_ctrl_map *ctrl_map; /* initialized at startup */
struct sisl_rht_entry *rht_start; /* 1 page (req'd for alignment),
alloc/free on attach/detach */
u32 rht_out; /* Number of checked out RHT entries */
u32 rht_perms; /* User-defined permissions for RHT entries */
struct llun_info **rht_lun; /* Mapping of RHT entries to LUNs */
struct cxl_ioctl_start_work work;
u64 ctxid;
int lfd;
pid_t pid;
bool unavail;
bool err_recovery_active;
struct mutex mutex; /* Context protection */
struct cxl_context *ctx;
struct list_head luns; /* LUNs attached to this context */
const struct vm_operations_struct *cxl_mmap_vmops;
struct file *file;
struct list_head list; /* Link contexts in error recovery */
};
struct cxlflash_global {
struct mutex mutex;
struct list_head gluns;/* list of glun_info structs */
struct page *err_page; /* One page of all 0xF for error notification */
};
int cxlflash_disk_release(struct scsi_device *, struct dk_cxlflash_release *);
int _cxlflash_disk_release(struct scsi_device *, struct ctx_info *,
struct dk_cxlflash_release *);
int cxlflash_lun_attach(struct glun_info *, enum lun_mode, bool);
void cxlflash_lun_detach(struct glun_info *);
struct ctx_info *get_context(struct cxlflash_cfg *, u64, void *, enum ctx_ctrl);
void put_context(struct ctx_info *);
struct sisl_rht_entry *get_rhte(struct ctx_info *, res_hndl_t,
struct llun_info *);
struct sisl_rht_entry *rhte_checkout(struct ctx_info *, struct llun_info *);
void rhte_checkin(struct ctx_info *, struct sisl_rht_entry *);
int cxlflash_manage_lun(struct scsi_device *, struct dk_cxlflash_manage_lun *);
#endif /* ifndef _CXLFLASH_SUPERPIPE_H */

1
include/uapi/scsi/Kbuild
View File

@ -3,3 +3,4 @@ header-y += fc/
header-y += scsi_bsg_fc.h
header-y += scsi_netlink.h
header-y += scsi_netlink_fc.h
header-y += cxlflash_ioctl.h

140
include/uapi/scsi/cxlflash_ioctl.h 100644
View File

@ -0,0 +1,140 @@
/*
* 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.
*/
#ifndef _CXLFLASH_IOCTL_H
#define _CXLFLASH_IOCTL_H
#include <linux/types.h>
/*
* Structure and flag definitions CXL Flash superpipe ioctls
*/
#define DK_CXLFLASH_VERSION_0 0
struct dk_cxlflash_hdr {
__u16 version; /* Version data */
__u16 rsvd[3]; /* Reserved for future use */
__u64 flags; /* Input flags */
__u64 return_flags; /* Returned flags */
};
/*
* Notes:
* -----
* The 'context_id' field of all ioctl structures contains the context
* identifier for a context in the lower 32-bits (upper 32-bits are not
* to be used when identifying a context to the AFU). That said, the value
* in its entirety (all 64-bits) is to be treated as an opaque cookie and
* should be presented as such when issuing ioctls.
*
* For DK_CXLFLASH_ATTACH ioctl, user specifies read/write access
* permissions via the O_RDONLY, O_WRONLY, and O_RDWR flags defined in
* the fcntl.h header file.
*/
#define DK_CXLFLASH_ATTACH_REUSE_CONTEXT 0x8000000000000000ULL
struct dk_cxlflash_attach {
struct dk_cxlflash_hdr hdr; /* Common fields */
__u64 num_interrupts; /* Requested number of interrupts */
__u64 context_id; /* Returned context */
__u64 mmio_size; /* Returned size of MMIO area */
__u64 block_size; /* Returned block size, in bytes */
__u64 adap_fd; /* Returned adapter file descriptor */
__u64 last_lba; /* Returned last LBA on the device */
__u64 max_xfer; /* Returned max transfer size, blocks */
__u64 reserved[8]; /* Reserved for future use */
};
struct dk_cxlflash_detach {
struct dk_cxlflash_hdr hdr; /* Common fields */
__u64 context_id; /* Context to detach */
__u64 reserved[8]; /* Reserved for future use */
};
struct dk_cxlflash_udirect {
struct dk_cxlflash_hdr hdr; /* Common fields */
__u64 context_id; /* Context to own physical resources */
__u64 rsrc_handle; /* Returned resource handle */
__u64 last_lba; /* Returned last LBA on the device */
__u64 reserved[8]; /* Reserved for future use */
};
struct dk_cxlflash_release {
struct dk_cxlflash_hdr hdr; /* Common fields */
__u64 context_id; /* Context owning resources */
__u64 rsrc_handle; /* Resource handle to release */
__u64 reserved[8]; /* Reserved for future use */
};
#define DK_CXLFLASH_VERIFY_SENSE_LEN 18
#define DK_CXLFLASH_VERIFY_HINT_SENSE 0x8000000000000000ULL
struct dk_cxlflash_verify {
struct dk_cxlflash_hdr hdr; /* Common fields */
__u64 context_id; /* Context owning resources to verify */
__u64 rsrc_handle; /* Resource handle of LUN */
__u64 hint; /* Reasons for verify */
__u64 last_lba; /* Returned last LBA of device */
__u8 sense_data[DK_CXLFLASH_VERIFY_SENSE_LEN]; /* SCSI sense data */
__u8 pad[6]; /* Pad to next 8-byte boundary */
__u64 reserved[8]; /* Reserved for future use */
};
#define DK_CXLFLASH_RECOVER_AFU_CONTEXT_RESET 0x8000000000000000ULL
struct dk_cxlflash_recover_afu {
struct dk_cxlflash_hdr hdr; /* Common fields */
__u64 reason; /* Reason for recovery request */
__u64 context_id; /* Context to recover / updated ID */
__u64 mmio_size; /* Returned size of MMIO area */
__u64 adap_fd; /* Returned adapter file descriptor */
__u64 reserved[8]; /* Reserved for future use */
};
#define DK_CXLFLASH_MANAGE_LUN_WWID_LEN 16
#define DK_CXLFLASH_MANAGE_LUN_ENABLE_SUPERPIPE 0x8000000000000000ULL
#define DK_CXLFLASH_MANAGE_LUN_DISABLE_SUPERPIPE 0x4000000000000000ULL
#define DK_CXLFLASH_MANAGE_LUN_ALL_PORTS_ACCESSIBLE 0x2000000000000000ULL
struct dk_cxlflash_manage_lun {
struct dk_cxlflash_hdr hdr; /* Common fields */
__u8 wwid[DK_CXLFLASH_MANAGE_LUN_WWID_LEN]; /* Page83 WWID, NAA-6 */
__u64 reserved[8]; /* Rsvd, future use */
};
union cxlflash_ioctls {
struct dk_cxlflash_attach attach;
struct dk_cxlflash_detach detach;
struct dk_cxlflash_udirect udirect;
struct dk_cxlflash_release release;
struct dk_cxlflash_verify verify;
struct dk_cxlflash_recover_afu recover_afu;
struct dk_cxlflash_manage_lun manage_lun;
};
#define MAX_CXLFLASH_IOCTL_SZ (sizeof(union cxlflash_ioctls))
#define CXL_MAGIC 0xCA
#define CXL_IOWR(_n, _s) _IOWR(CXL_MAGIC, _n, struct _s)
#define DK_CXLFLASH_ATTACH CXL_IOWR(0x80, dk_cxlflash_attach)
#define DK_CXLFLASH_USER_DIRECT CXL_IOWR(0x81, dk_cxlflash_udirect)
#define DK_CXLFLASH_RELEASE CXL_IOWR(0x82, dk_cxlflash_release)
#define DK_CXLFLASH_DETACH CXL_IOWR(0x83, dk_cxlflash_detach)
#define DK_CXLFLASH_VERIFY CXL_IOWR(0x84, dk_cxlflash_verify)
#define DK_CXLFLASH_RECOVER_AFU CXL_IOWR(0x85, dk_cxlflash_recover_afu)
#define DK_CXLFLASH_MANAGE_LUN CXL_IOWR(0x86, dk_cxlflash_manage_lun)
#endif /* ifndef _CXLFLASH_IOCTL_H */