Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 1399 insertions, 0 deletions

diff --git a/drivers/scsi/cxlflash/ocxl_hw.c b/drivers/scsi/cxlflash/ocxl_hw.c
new file mode 100644
index 000000000..631eda2d4
--- /dev/null
+++ b/drivers/scsi/cxlflash/ocxl_hw.c
@@ -0,0 +1,1399 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * CXL Flash Device Driver
+ *
+ * Written by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com>, IBM Corporation
+ *             Uma Krishnan <ukrishn@linux.vnet.ibm.com>, IBM Corporation
+ *
+ * Copyright (C) 2018 IBM Corporation
+ */
+
+#include <linux/file.h>
+#include <linux/idr.h>
+#include <linux/module.h>
+#include <linux/mount.h>
+#include <linux/pseudo_fs.h>
+#include <linux/poll.h>
+#include <linux/sched/signal.h>
+#include <linux/interrupt.h>
+#include <linux/irqdomain.h>
+#include <asm/xive.h>
+#include <misc/ocxl.h>
+
+#include <uapi/misc/cxl.h>
+
+#include "backend.h"
+#include "ocxl_hw.h"
+
+/*
+ * Pseudo-filesystem to allocate inodes.
+ */
+
+#define OCXLFLASH_FS_MAGIC      0x1697698f
+
+static int ocxlflash_fs_cnt;
+static struct vfsmount *ocxlflash_vfs_mount;
+
+static int ocxlflash_fs_init_fs_context(struct fs_context *fc)
+{
+	return init_pseudo(fc, OCXLFLASH_FS_MAGIC) ? 0 : -ENOMEM;
+}
+
+static struct file_system_type ocxlflash_fs_type = {
+	.name		= "ocxlflash",
+	.owner		= THIS_MODULE,
+	.init_fs_context = ocxlflash_fs_init_fs_context,
+	.kill_sb	= kill_anon_super,
+};
+
+/*
+ * ocxlflash_release_mapping() - release the memory mapping
+ * @ctx:	Context whose mapping is to be released.
+ */
+static void ocxlflash_release_mapping(struct ocxlflash_context *ctx)
+{
+	if (ctx->mapping)
+		simple_release_fs(&ocxlflash_vfs_mount, &ocxlflash_fs_cnt);
+	ctx->mapping = NULL;
+}
+
+/*
+ * ocxlflash_getfile() - allocate pseudo filesystem, inode, and the file
+ * @dev:	Generic device of the host.
+ * @name:	Name of the pseudo filesystem.
+ * @fops:	File operations.
+ * @priv:	Private data.
+ * @flags:	Flags for the file.
+ *
+ * Return: pointer to the file on success, ERR_PTR on failure
+ */
+static struct file *ocxlflash_getfile(struct device *dev, const char *name,
+				      const struct file_operations *fops,
+				      void *priv, int flags)
+{
+	struct file *file;
+	struct inode *inode;
+	int rc;
+
+	if (fops->owner && !try_module_get(fops->owner)) {
+		dev_err(dev, "%s: Owner does not exist\n", __func__);
+		rc = -ENOENT;
+		goto err1;
+	}
+
+	rc = simple_pin_fs(&ocxlflash_fs_type, &ocxlflash_vfs_mount,
+			   &ocxlflash_fs_cnt);
+	if (unlikely(rc < 0)) {
+		dev_err(dev, "%s: Cannot mount ocxlflash pseudofs rc=%d\n",
+			__func__, rc);
+		goto err2;
+	}
+
+	inode = alloc_anon_inode(ocxlflash_vfs_mount->mnt_sb);
+	if (IS_ERR(inode)) {
+		rc = PTR_ERR(inode);
+		dev_err(dev, "%s: alloc_anon_inode failed rc=%d\n",
+			__func__, rc);
+		goto err3;
+	}
+
+	file = alloc_file_pseudo(inode, ocxlflash_vfs_mount, name,
+				 flags & (O_ACCMODE | O_NONBLOCK), fops);
+	if (IS_ERR(file)) {
+		rc = PTR_ERR(file);
+		dev_err(dev, "%s: alloc_file failed rc=%d\n",
+			__func__, rc);
+		goto err4;
+	}
+
+	file->private_data = priv;
+out:
+	return file;
+err4:
+	iput(inode);
+err3:
+	simple_release_fs(&ocxlflash_vfs_mount, &ocxlflash_fs_cnt);
+err2:
+	module_put(fops->owner);
+err1:
+	file = ERR_PTR(rc);
+	goto out;
+}
+
+/**
+ * ocxlflash_psa_map() - map the process specific MMIO space
+ * @ctx_cookie:	Adapter context for which the mapping needs to be done.
+ *
+ * Return: MMIO pointer of the mapped region
+ */
+static void __iomem *ocxlflash_psa_map(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+	struct device *dev = ctx->hw_afu->dev;
+
+	mutex_lock(&ctx->state_mutex);
+	if (ctx->state != STARTED) {
+		dev_err(dev, "%s: Context not started, state=%d\n", __func__,
+			ctx->state);
+		mutex_unlock(&ctx->state_mutex);
+		return NULL;
+	}
+	mutex_unlock(&ctx->state_mutex);
+
+	return ioremap(ctx->psn_phys, ctx->psn_size);
+}
+
+/**
+ * ocxlflash_psa_unmap() - unmap the process specific MMIO space
+ * @addr:	MMIO pointer to unmap.
+ */
+static void ocxlflash_psa_unmap(void __iomem *addr)
+{
+	iounmap(addr);
+}
+
+/**
+ * ocxlflash_process_element() - get process element of the adapter context
+ * @ctx_cookie:	Adapter context associated with the process element.
+ *
+ * Return: process element of the adapter context
+ */
+static int ocxlflash_process_element(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+
+	return ctx->pe;
+}
+
+/**
+ * afu_map_irq() - map the interrupt of the adapter context
+ * @flags:	Flags.
+ * @ctx:	Adapter context.
+ * @num:	Per-context AFU interrupt number.
+ * @handler:	Interrupt handler to register.
+ * @cookie:	Interrupt handler private data.
+ * @name:	Name of the interrupt.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int afu_map_irq(u64 flags, struct ocxlflash_context *ctx, int num,
+		       irq_handler_t handler, void *cookie, char *name)
+{
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct device *dev = afu->dev;
+	struct ocxlflash_irqs *irq;
+	struct xive_irq_data *xd;
+	u32 virq;
+	int rc = 0;
+
+	if (num < 0 || num >= ctx->num_irqs) {
+		dev_err(dev, "%s: Interrupt %d not allocated\n", __func__, num);
+		rc = -ENOENT;
+		goto out;
+	}
+
+	irq = &ctx->irqs[num];
+	virq = irq_create_mapping(NULL, irq->hwirq);
+	if (unlikely(!virq)) {
+		dev_err(dev, "%s: irq_create_mapping failed\n", __func__);
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	rc = request_irq(virq, handler, 0, name, cookie);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: request_irq failed rc=%d\n", __func__, rc);
+		goto err1;
+	}
+
+	xd = irq_get_handler_data(virq);
+	if (unlikely(!xd)) {
+		dev_err(dev, "%s: Can't get interrupt data\n", __func__);
+		rc = -ENXIO;
+		goto err2;
+	}
+
+	irq->virq = virq;
+	irq->vtrig = xd->trig_mmio;
+out:
+	return rc;
+err2:
+	free_irq(virq, cookie);
+err1:
+	irq_dispose_mapping(virq);
+	goto out;
+}
+
+/**
+ * ocxlflash_map_afu_irq() - map the interrupt of the adapter context
+ * @ctx_cookie:	Adapter context.
+ * @num:	Per-context AFU interrupt number.
+ * @handler:	Interrupt handler to register.
+ * @cookie:	Interrupt handler private data.
+ * @name:	Name of the interrupt.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_map_afu_irq(void *ctx_cookie, int num,
+				 irq_handler_t handler, void *cookie,
+				 char *name)
+{
+	return afu_map_irq(0, ctx_cookie, num, handler, cookie, name);
+}
+
+/**
+ * afu_unmap_irq() - unmap the interrupt
+ * @flags:	Flags.
+ * @ctx:	Adapter context.
+ * @num:	Per-context AFU interrupt number.
+ * @cookie:	Interrupt handler private data.
+ */
+static void afu_unmap_irq(u64 flags, struct ocxlflash_context *ctx, int num,
+			  void *cookie)
+{
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct device *dev = afu->dev;
+	struct ocxlflash_irqs *irq;
+
+	if (num < 0 || num >= ctx->num_irqs) {
+		dev_err(dev, "%s: Interrupt %d not allocated\n", __func__, num);
+		return;
+	}
+
+	irq = &ctx->irqs[num];
+
+	if (irq_find_mapping(NULL, irq->hwirq)) {
+		free_irq(irq->virq, cookie);
+		irq_dispose_mapping(irq->virq);
+	}
+
+	memset(irq, 0, sizeof(*irq));
+}
+
+/**
+ * ocxlflash_unmap_afu_irq() - unmap the interrupt
+ * @ctx_cookie:	Adapter context.
+ * @num:	Per-context AFU interrupt number.
+ * @cookie:	Interrupt handler private data.
+ */
+static void ocxlflash_unmap_afu_irq(void *ctx_cookie, int num, void *cookie)
+{
+	return afu_unmap_irq(0, ctx_cookie, num, cookie);
+}
+
+/**
+ * ocxlflash_get_irq_objhndl() - get the object handle for an interrupt
+ * @ctx_cookie:	Context associated with the interrupt.
+ * @irq:	Interrupt number.
+ *
+ * Return: effective address of the mapped region
+ */
+static u64 ocxlflash_get_irq_objhndl(void *ctx_cookie, int irq)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+
+	if (irq < 0 || irq >= ctx->num_irqs)
+		return 0;
+
+	return (__force u64)ctx->irqs[irq].vtrig;
+}
+
+/**
+ * ocxlflash_xsl_fault() - callback when translation error is triggered
+ * @data:	Private data provided at callback registration, the context.
+ * @addr:	Address that triggered the error.
+ * @dsisr:	Value of dsisr register.
+ */
+static void ocxlflash_xsl_fault(void *data, u64 addr, u64 dsisr)
+{
+	struct ocxlflash_context *ctx = data;
+
+	spin_lock(&ctx->slock);
+	ctx->fault_addr = addr;
+	ctx->fault_dsisr = dsisr;
+	ctx->pending_fault = true;
+	spin_unlock(&ctx->slock);
+
+	wake_up_all(&ctx->wq);
+}
+
+/**
+ * start_context() - local routine to start a context
+ * @ctx:	Adapter context to be started.
+ *
+ * Assign the context specific MMIO space, add and enable the PE.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int start_context(struct ocxlflash_context *ctx)
+{
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct ocxl_afu_config *acfg = &afu->acfg;
+	void *link_token = afu->link_token;
+	struct pci_dev *pdev = afu->pdev;
+	struct device *dev = afu->dev;
+	bool master = ctx->master;
+	struct mm_struct *mm;
+	int rc = 0;
+	u32 pid;
+
+	mutex_lock(&ctx->state_mutex);
+	if (ctx->state != OPENED) {
+		dev_err(dev, "%s: Context state invalid, state=%d\n",
+			__func__, ctx->state);
+		rc = -EINVAL;
+		goto out;
+	}
+
+	if (master) {
+		ctx->psn_size = acfg->global_mmio_size;
+		ctx->psn_phys = afu->gmmio_phys;
+	} else {
+		ctx->psn_size = acfg->pp_mmio_stride;
+		ctx->psn_phys = afu->ppmmio_phys + (ctx->pe * ctx->psn_size);
+	}
+
+	/* pid and mm not set for master contexts */
+	if (master) {
+		pid = 0;
+		mm = NULL;
+	} else {
+		pid = current->mm->context.id;
+		mm = current->mm;
+	}
+
+	rc = ocxl_link_add_pe(link_token, ctx->pe, pid, 0, 0,
+			      pci_dev_id(pdev), mm, ocxlflash_xsl_fault,
+			      ctx);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_link_add_pe failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+
+	ctx->state = STARTED;
+out:
+	mutex_unlock(&ctx->state_mutex);
+	return rc;
+}
+
+/**
+ * ocxlflash_start_context() - start a kernel context
+ * @ctx_cookie:	Adapter context to be started.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_start_context(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+
+	return start_context(ctx);
+}
+
+/**
+ * ocxlflash_stop_context() - stop a context
+ * @ctx_cookie:	Adapter context to be stopped.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_stop_context(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct ocxl_afu_config *acfg = &afu->acfg;
+	struct pci_dev *pdev = afu->pdev;
+	struct device *dev = afu->dev;
+	enum ocxlflash_ctx_state state;
+	int rc = 0;
+
+	mutex_lock(&ctx->state_mutex);
+	state = ctx->state;
+	ctx->state = CLOSED;
+	mutex_unlock(&ctx->state_mutex);
+	if (state != STARTED)
+		goto out;
+
+	rc = ocxl_config_terminate_pasid(pdev, acfg->dvsec_afu_control_pos,
+					 ctx->pe);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_config_terminate_pasid failed rc=%d\n",
+			__func__, rc);
+		/* If EBUSY, PE could be referenced in future by the AFU */
+		if (rc == -EBUSY)
+			goto out;
+	}
+
+	rc = ocxl_link_remove_pe(afu->link_token, ctx->pe);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_link_remove_pe failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+out:
+	return rc;
+}
+
+/**
+ * ocxlflash_afu_reset() - reset the AFU
+ * @ctx_cookie:	Adapter context.
+ */
+static int ocxlflash_afu_reset(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+	struct device *dev = ctx->hw_afu->dev;
+
+	/* Pending implementation from OCXL transport services */
+	dev_err_once(dev, "%s: afu_reset() fop not supported\n", __func__);
+
+	/* Silently return success until it is implemented */
+	return 0;
+}
+
+/**
+ * ocxlflash_set_master() - sets the context as master
+ * @ctx_cookie:	Adapter context to set as master.
+ */
+static void ocxlflash_set_master(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+
+	ctx->master = true;
+}
+
+/**
+ * ocxlflash_get_context() - obtains the context associated with the host
+ * @pdev:	PCI device associated with the host.
+ * @afu_cookie:	Hardware AFU associated with the host.
+ *
+ * Return: returns the pointer to host adapter context
+ */
+static void *ocxlflash_get_context(struct pci_dev *pdev, void *afu_cookie)
+{
+	struct ocxl_hw_afu *afu = afu_cookie;
+
+	return afu->ocxl_ctx;
+}
+
+/**
+ * ocxlflash_dev_context_init() - allocate and initialize an adapter context
+ * @pdev:	PCI device associated with the host.
+ * @afu_cookie:	Hardware AFU associated with the host.
+ *
+ * Return: returns the adapter context on success, ERR_PTR on failure
+ */
+static void *ocxlflash_dev_context_init(struct pci_dev *pdev, void *afu_cookie)
+{
+	struct ocxl_hw_afu *afu = afu_cookie;
+	struct device *dev = afu->dev;
+	struct ocxlflash_context *ctx;
+	int rc;
+
+	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
+	if (unlikely(!ctx)) {
+		dev_err(dev, "%s: Context allocation failed\n", __func__);
+		rc = -ENOMEM;
+		goto err1;
+	}
+
+	idr_preload(GFP_KERNEL);
+	rc = idr_alloc(&afu->idr, ctx, 0, afu->max_pasid, GFP_NOWAIT);
+	idr_preload_end();
+	if (unlikely(rc < 0)) {
+		dev_err(dev, "%s: idr_alloc failed rc=%d\n", __func__, rc);
+		goto err2;
+	}
+
+	spin_lock_init(&ctx->slock);
+	init_waitqueue_head(&ctx->wq);
+	mutex_init(&ctx->state_mutex);
+
+	ctx->state = OPENED;
+	ctx->pe = rc;
+	ctx->master = false;
+	ctx->mapping = NULL;
+	ctx->hw_afu = afu;
+	ctx->irq_bitmap = 0;
+	ctx->pending_irq = false;
+	ctx->pending_fault = false;
+out:
+	return ctx;
+err2:
+	kfree(ctx);
+err1:
+	ctx = ERR_PTR(rc);
+	goto out;
+}
+
+/**
+ * ocxlflash_release_context() - releases an adapter context
+ * @ctx_cookie:	Adapter context to be released.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_release_context(void *ctx_cookie)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+	struct device *dev;
+	int rc = 0;
+
+	if (!ctx)
+		goto out;
+
+	dev = ctx->hw_afu->dev;
+	mutex_lock(&ctx->state_mutex);
+	if (ctx->state >= STARTED) {
+		dev_err(dev, "%s: Context in use, state=%d\n", __func__,
+			ctx->state);
+		mutex_unlock(&ctx->state_mutex);
+		rc = -EBUSY;
+		goto out;
+	}
+	mutex_unlock(&ctx->state_mutex);
+
+	idr_remove(&ctx->hw_afu->idr, ctx->pe);
+	ocxlflash_release_mapping(ctx);
+	kfree(ctx);
+out:
+	return rc;
+}
+
+/**
+ * ocxlflash_perst_reloads_same_image() - sets the image reload policy
+ * @afu_cookie:	Hardware AFU associated with the host.
+ * @image:	Whether to load the same image on PERST.
+ */
+static void ocxlflash_perst_reloads_same_image(void *afu_cookie, bool image)
+{
+	struct ocxl_hw_afu *afu = afu_cookie;
+
+	afu->perst_same_image = image;
+}
+
+/**
+ * ocxlflash_read_adapter_vpd() - reads the adapter VPD
+ * @pdev:	PCI device associated with the host.
+ * @buf:	Buffer to get the VPD data.
+ * @count:	Size of buffer (maximum bytes that can be read).
+ *
+ * Return: size of VPD on success, -errno on failure
+ */
+static ssize_t ocxlflash_read_adapter_vpd(struct pci_dev *pdev, void *buf,
+					  size_t count)
+{
+	return pci_read_vpd(pdev, 0, count, buf);
+}
+
+/**
+ * free_afu_irqs() - internal service to free interrupts
+ * @ctx:	Adapter context.
+ */
+static void free_afu_irqs(struct ocxlflash_context *ctx)
+{
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct device *dev = afu->dev;
+	int i;
+
+	if (!ctx->irqs) {
+		dev_err(dev, "%s: Interrupts not allocated\n", __func__);
+		return;
+	}
+
+	for (i = ctx->num_irqs; i >= 0; i--)
+		ocxl_link_free_irq(afu->link_token, ctx->irqs[i].hwirq);
+
+	kfree(ctx->irqs);
+	ctx->irqs = NULL;
+}
+
+/**
+ * alloc_afu_irqs() - internal service to allocate interrupts
+ * @ctx:	Context associated with the request.
+ * @num:	Number of interrupts requested.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int alloc_afu_irqs(struct ocxlflash_context *ctx, int num)
+{
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct device *dev = afu->dev;
+	struct ocxlflash_irqs *irqs;
+	int rc = 0;
+	int hwirq;
+	int i;
+
+	if (ctx->irqs) {
+		dev_err(dev, "%s: Interrupts already allocated\n", __func__);
+		rc = -EEXIST;
+		goto out;
+	}
+
+	if (num > OCXL_MAX_IRQS) {
+		dev_err(dev, "%s: Too many interrupts num=%d\n", __func__, num);
+		rc = -EINVAL;
+		goto out;
+	}
+
+	irqs = kcalloc(num, sizeof(*irqs), GFP_KERNEL);
+	if (unlikely(!irqs)) {
+		dev_err(dev, "%s: Context irqs allocation failed\n", __func__);
+		rc = -ENOMEM;
+		goto out;
+	}
+
+	for (i = 0; i < num; i++) {
+		rc = ocxl_link_irq_alloc(afu->link_token, &hwirq);
+		if (unlikely(rc)) {
+			dev_err(dev, "%s: ocxl_link_irq_alloc failed rc=%d\n",
+				__func__, rc);
+			goto err;
+		}
+
+		irqs[i].hwirq = hwirq;
+	}
+
+	ctx->irqs = irqs;
+	ctx->num_irqs = num;
+out:
+	return rc;
+err:
+	for (i = i-1; i >= 0; i--)
+		ocxl_link_free_irq(afu->link_token, irqs[i].hwirq);
+	kfree(irqs);
+	goto out;
+}
+
+/**
+ * ocxlflash_allocate_afu_irqs() - allocates the requested number of interrupts
+ * @ctx_cookie:	Context associated with the request.
+ * @num:	Number of interrupts requested.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_allocate_afu_irqs(void *ctx_cookie, int num)
+{
+	return alloc_afu_irqs(ctx_cookie, num);
+}
+
+/**
+ * ocxlflash_free_afu_irqs() - frees the interrupts of an adapter context
+ * @ctx_cookie:	Adapter context.
+ */
+static void ocxlflash_free_afu_irqs(void *ctx_cookie)
+{
+	free_afu_irqs(ctx_cookie);
+}
+
+/**
+ * ocxlflash_unconfig_afu() - unconfigure the AFU
+ * @afu: AFU associated with the host.
+ */
+static void ocxlflash_unconfig_afu(struct ocxl_hw_afu *afu)
+{
+	if (afu->gmmio_virt) {
+		iounmap(afu->gmmio_virt);
+		afu->gmmio_virt = NULL;
+	}
+}
+
+/**
+ * ocxlflash_destroy_afu() - destroy the AFU structure
+ * @afu_cookie:	AFU to be freed.
+ */
+static void ocxlflash_destroy_afu(void *afu_cookie)
+{
+	struct ocxl_hw_afu *afu = afu_cookie;
+	int pos;
+
+	if (!afu)
+		return;
+
+	ocxlflash_release_context(afu->ocxl_ctx);
+	idr_destroy(&afu->idr);
+
+	/* Disable the AFU */
+	pos = afu->acfg.dvsec_afu_control_pos;
+	ocxl_config_set_afu_state(afu->pdev, pos, 0);
+
+	ocxlflash_unconfig_afu(afu);
+	kfree(afu);
+}
+
+/**
+ * ocxlflash_config_fn() - configure the host function
+ * @pdev:	PCI device associated with the host.
+ * @afu:	AFU associated with the host.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_config_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
+{
+	struct ocxl_fn_config *fcfg = &afu->fcfg;
+	struct device *dev = &pdev->dev;
+	u16 base, enabled, supported;
+	int rc = 0;
+
+	/* Read DVSEC config of the function */
+	rc = ocxl_config_read_function(pdev, fcfg);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_config_read_function failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+
+	/* Check if function has AFUs defined, only 1 per function supported */
+	if (fcfg->max_afu_index >= 0) {
+		afu->is_present = true;
+		if (fcfg->max_afu_index != 0)
+			dev_warn(dev, "%s: Unexpected AFU index value %d\n",
+				 __func__, fcfg->max_afu_index);
+	}
+
+	rc = ocxl_config_get_actag_info(pdev, &base, &enabled, &supported);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_config_get_actag_info failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+
+	afu->fn_actag_base = base;
+	afu->fn_actag_enabled = enabled;
+
+	ocxl_config_set_actag(pdev, fcfg->dvsec_function_pos, base, enabled);
+	dev_dbg(dev, "%s: Function acTag range base=%u enabled=%u\n",
+		__func__, base, enabled);
+
+	rc = ocxl_link_setup(pdev, 0, &afu->link_token);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_link_setup failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+
+	rc = ocxl_config_set_TL(pdev, fcfg->dvsec_tl_pos);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_config_set_TL failed rc=%d\n",
+			__func__, rc);
+		goto err;
+	}
+out:
+	return rc;
+err:
+	ocxl_link_release(pdev, afu->link_token);
+	goto out;
+}
+
+/**
+ * ocxlflash_unconfig_fn() - unconfigure the host function
+ * @pdev:	PCI device associated with the host.
+ * @afu:	AFU associated with the host.
+ */
+static void ocxlflash_unconfig_fn(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
+{
+	ocxl_link_release(pdev, afu->link_token);
+}
+
+/**
+ * ocxlflash_map_mmio() - map the AFU MMIO space
+ * @afu: AFU associated with the host.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_map_mmio(struct ocxl_hw_afu *afu)
+{
+	struct ocxl_afu_config *acfg = &afu->acfg;
+	struct pci_dev *pdev = afu->pdev;
+	struct device *dev = afu->dev;
+	phys_addr_t gmmio, ppmmio;
+	int rc = 0;
+
+	rc = pci_request_region(pdev, acfg->global_mmio_bar, "ocxlflash");
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: pci_request_region for global failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+	gmmio = pci_resource_start(pdev, acfg->global_mmio_bar);
+	gmmio += acfg->global_mmio_offset;
+
+	rc = pci_request_region(pdev, acfg->pp_mmio_bar, "ocxlflash");
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: pci_request_region for pp bar failed rc=%d\n",
+			__func__, rc);
+		goto err1;
+	}
+	ppmmio = pci_resource_start(pdev, acfg->pp_mmio_bar);
+	ppmmio += acfg->pp_mmio_offset;
+
+	afu->gmmio_virt = ioremap(gmmio, acfg->global_mmio_size);
+	if (unlikely(!afu->gmmio_virt)) {
+		dev_err(dev, "%s: MMIO mapping failed\n", __func__);
+		rc = -ENOMEM;
+		goto err2;
+	}
+
+	afu->gmmio_phys = gmmio;
+	afu->ppmmio_phys = ppmmio;
+out:
+	return rc;
+err2:
+	pci_release_region(pdev, acfg->pp_mmio_bar);
+err1:
+	pci_release_region(pdev, acfg->global_mmio_bar);
+	goto out;
+}
+
+/**
+ * ocxlflash_config_afu() - configure the host AFU
+ * @pdev:	PCI device associated with the host.
+ * @afu:	AFU associated with the host.
+ *
+ * Must be called _after_ host function configuration.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_config_afu(struct pci_dev *pdev, struct ocxl_hw_afu *afu)
+{
+	struct ocxl_afu_config *acfg = &afu->acfg;
+	struct ocxl_fn_config *fcfg = &afu->fcfg;
+	struct device *dev = &pdev->dev;
+	int count;
+	int base;
+	int pos;
+	int rc = 0;
+
+	/* This HW AFU function does not have any AFUs defined */
+	if (!afu->is_present)
+		goto out;
+
+	/* Read AFU config at index 0 */
+	rc = ocxl_config_read_afu(pdev, fcfg, acfg, 0);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxl_config_read_afu failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+
+	/* Only one AFU per function is supported, so actag_base is same */
+	base = afu->fn_actag_base;
+	count = min_t(int, acfg->actag_supported, afu->fn_actag_enabled);
+	pos = acfg->dvsec_afu_control_pos;
+
+	ocxl_config_set_afu_actag(pdev, pos, base, count);
+	dev_dbg(dev, "%s: acTag base=%d enabled=%d\n", __func__, base, count);
+	afu->afu_actag_base = base;
+	afu->afu_actag_enabled = count;
+	afu->max_pasid = 1 << acfg->pasid_supported_log;
+
+	ocxl_config_set_afu_pasid(pdev, pos, 0, acfg->pasid_supported_log);
+
+	rc = ocxlflash_map_mmio(afu);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: ocxlflash_map_mmio failed rc=%d\n",
+			__func__, rc);
+		goto out;
+	}
+
+	/* Enable the AFU */
+	ocxl_config_set_afu_state(pdev, acfg->dvsec_afu_control_pos, 1);
+out:
+	return rc;
+}
+
+/**
+ * ocxlflash_create_afu() - create the AFU for OCXL
+ * @pdev:	PCI device associated with the host.
+ *
+ * Return: AFU on success, NULL on failure
+ */
+static void *ocxlflash_create_afu(struct pci_dev *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct ocxlflash_context *ctx;
+	struct ocxl_hw_afu *afu;
+	int rc;
+
+	afu = kzalloc(sizeof(*afu), GFP_KERNEL);
+	if (unlikely(!afu)) {
+		dev_err(dev, "%s: HW AFU allocation failed\n", __func__);
+		goto out;
+	}
+
+	afu->pdev = pdev;
+	afu->dev = dev;
+	idr_init(&afu->idr);
+
+	rc = ocxlflash_config_fn(pdev, afu);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: Function configuration failed rc=%d\n",
+			__func__, rc);
+		goto err1;
+	}
+
+	rc = ocxlflash_config_afu(pdev, afu);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: AFU configuration failed rc=%d\n",
+			__func__, rc);
+		goto err2;
+	}
+
+	ctx = ocxlflash_dev_context_init(pdev, afu);
+	if (IS_ERR(ctx)) {
+		rc = PTR_ERR(ctx);
+		dev_err(dev, "%s: ocxlflash_dev_context_init failed rc=%d\n",
+			__func__, rc);
+		goto err3;
+	}
+
+	afu->ocxl_ctx = ctx;
+out:
+	return afu;
+err3:
+	ocxlflash_unconfig_afu(afu);
+err2:
+	ocxlflash_unconfig_fn(pdev, afu);
+err1:
+	idr_destroy(&afu->idr);
+	kfree(afu);
+	afu = NULL;
+	goto out;
+}
+
+/**
+ * ctx_event_pending() - check for any event pending on the context
+ * @ctx:	Context to be checked.
+ *
+ * Return: true if there is an event pending, false if none pending
+ */
+static inline bool ctx_event_pending(struct ocxlflash_context *ctx)
+{
+	if (ctx->pending_irq || ctx->pending_fault)
+		return true;
+
+	return false;
+}
+
+/**
+ * afu_poll() - poll the AFU for events on the context
+ * @file:	File associated with the adapter context.
+ * @poll:	Poll structure from the user.
+ *
+ * Return: poll mask
+ */
+static unsigned int afu_poll(struct file *file, struct poll_table_struct *poll)
+{
+	struct ocxlflash_context *ctx = file->private_data;
+	struct device *dev = ctx->hw_afu->dev;
+	ulong lock_flags;
+	int mask = 0;
+
+	poll_wait(file, &ctx->wq, poll);
+
+	spin_lock_irqsave(&ctx->slock, lock_flags);
+	if (ctx_event_pending(ctx))
+		mask |= POLLIN | POLLRDNORM;
+	else if (ctx->state == CLOSED)
+		mask |= POLLERR;
+	spin_unlock_irqrestore(&ctx->slock, lock_flags);
+
+	dev_dbg(dev, "%s: Poll wait completed for pe %i mask %i\n",
+		__func__, ctx->pe, mask);
+
+	return mask;
+}
+
+/**
+ * afu_read() - perform a read on the context for any event
+ * @file:	File associated with the adapter context.
+ * @buf:	Buffer to receive the data.
+ * @count:	Size of buffer (maximum bytes that can be read).
+ * @off:	Offset.
+ *
+ * Return: size of the data read on success, -errno on failure
+ */
+static ssize_t afu_read(struct file *file, char __user *buf, size_t count,
+			loff_t *off)
+{
+	struct ocxlflash_context *ctx = file->private_data;
+	struct device *dev = ctx->hw_afu->dev;
+	struct cxl_event event;
+	ulong lock_flags;
+	ssize_t esize;
+	ssize_t rc;
+	int bit;
+	DEFINE_WAIT(event_wait);
+
+	if (*off != 0) {
+		dev_err(dev, "%s: Non-zero offset not supported, off=%lld\n",
+			__func__, *off);
+		rc = -EINVAL;
+		goto out;
+	}
+
+	spin_lock_irqsave(&ctx->slock, lock_flags);
+
+	for (;;) {
+		prepare_to_wait(&ctx->wq, &event_wait, TASK_INTERRUPTIBLE);
+
+		if (ctx_event_pending(ctx) || (ctx->state == CLOSED))
+			break;
+
+		if (file->f_flags & O_NONBLOCK) {
+			dev_err(dev, "%s: File cannot be blocked on I/O\n",
+				__func__);
+			rc = -EAGAIN;
+			goto err;
+		}
+
+		if (signal_pending(current)) {
+			dev_err(dev, "%s: Signal pending on the process\n",
+				__func__);
+			rc = -ERESTARTSYS;
+			goto err;
+		}
+
+		spin_unlock_irqrestore(&ctx->slock, lock_flags);
+		schedule();
+		spin_lock_irqsave(&ctx->slock, lock_flags);
+	}
+
+	finish_wait(&ctx->wq, &event_wait);
+
+	memset(&event, 0, sizeof(event));
+	event.header.process_element = ctx->pe;
+	event.header.size = sizeof(struct cxl_event_header);
+	if (ctx->pending_irq) {
+		esize = sizeof(struct cxl_event_afu_interrupt);
+		event.header.size += esize;
+		event.header.type = CXL_EVENT_AFU_INTERRUPT;
+
+		bit = find_first_bit(&ctx->irq_bitmap, ctx->num_irqs);
+		clear_bit(bit, &ctx->irq_bitmap);
+		event.irq.irq = bit + 1;
+		if (bitmap_empty(&ctx->irq_bitmap, ctx->num_irqs))
+			ctx->pending_irq = false;
+	} else if (ctx->pending_fault) {
+		event.header.size += sizeof(struct cxl_event_data_storage);
+		event.header.type = CXL_EVENT_DATA_STORAGE;
+		event.fault.addr = ctx->fault_addr;
+		event.fault.dsisr = ctx->fault_dsisr;
+		ctx->pending_fault = false;
+	}
+
+	spin_unlock_irqrestore(&ctx->slock, lock_flags);
+
+	if (copy_to_user(buf, &event, event.header.size)) {
+		dev_err(dev, "%s: copy_to_user failed\n", __func__);
+		rc = -EFAULT;
+		goto out;
+	}
+
+	rc = event.header.size;
+out:
+	return rc;
+err:
+	finish_wait(&ctx->wq, &event_wait);
+	spin_unlock_irqrestore(&ctx->slock, lock_flags);
+	goto out;
+}
+
+/**
+ * afu_release() - release and free the context
+ * @inode:	File inode pointer.
+ * @file:	File associated with the context.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int afu_release(struct inode *inode, struct file *file)
+{
+	struct ocxlflash_context *ctx = file->private_data;
+	int i;
+
+	/* Unmap and free the interrupts associated with the context */
+	for (i = ctx->num_irqs; i >= 0; i--)
+		afu_unmap_irq(0, ctx, i, ctx);
+	free_afu_irqs(ctx);
+
+	return ocxlflash_release_context(ctx);
+}
+
+/**
+ * ocxlflash_mmap_fault() - mmap fault handler
+ * @vmf:	VM fault associated with current fault.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static vm_fault_t ocxlflash_mmap_fault(struct vm_fault *vmf)
+{
+	struct vm_area_struct *vma = vmf->vma;
+	struct ocxlflash_context *ctx = vma->vm_file->private_data;
+	struct device *dev = ctx->hw_afu->dev;
+	u64 mmio_area, offset;
+
+	offset = vmf->pgoff << PAGE_SHIFT;
+	if (offset >= ctx->psn_size)
+		return VM_FAULT_SIGBUS;
+
+	mutex_lock(&ctx->state_mutex);
+	if (ctx->state != STARTED) {
+		dev_err(dev, "%s: Context not started, state=%d\n",
+			__func__, ctx->state);
+		mutex_unlock(&ctx->state_mutex);
+		return VM_FAULT_SIGBUS;
+	}
+	mutex_unlock(&ctx->state_mutex);
+
+	mmio_area = ctx->psn_phys;
+	mmio_area += offset;
+
+	return vmf_insert_pfn(vma, vmf->address, mmio_area >> PAGE_SHIFT);
+}
+
+static const struct vm_operations_struct ocxlflash_vmops = {
+	.fault = ocxlflash_mmap_fault,
+};
+
+/**
+ * afu_mmap() - map the fault handler operations
+ * @file:	File associated with the context.
+ * @vma:	VM area associated with mapping.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int afu_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct ocxlflash_context *ctx = file->private_data;
+
+	if ((vma_pages(vma) + vma->vm_pgoff) >
+	    (ctx->psn_size >> PAGE_SHIFT))
+		return -EINVAL;
+
+	vma->vm_flags |= VM_IO | VM_PFNMAP;
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+	vma->vm_ops = &ocxlflash_vmops;
+	return 0;
+}
+
+static const struct file_operations ocxl_afu_fops = {
+	.owner		= THIS_MODULE,
+	.poll		= afu_poll,
+	.read		= afu_read,
+	.release	= afu_release,
+	.mmap		= afu_mmap,
+};
+
+#define PATCH_FOPS(NAME)						\
+	do { if (!fops->NAME) fops->NAME = ocxl_afu_fops.NAME; } while (0)
+
+/**
+ * ocxlflash_get_fd() - get file descriptor for an adapter context
+ * @ctx_cookie:	Adapter context.
+ * @fops:	File operations to be associated.
+ * @fd:		File descriptor to be returned back.
+ *
+ * Return: pointer to the file on success, ERR_PTR on failure
+ */
+static struct file *ocxlflash_get_fd(void *ctx_cookie,
+				     struct file_operations *fops, int *fd)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+	struct device *dev = ctx->hw_afu->dev;
+	struct file *file;
+	int flags, fdtmp;
+	int rc = 0;
+	char *name = NULL;
+
+	/* Only allow one fd per context */
+	if (ctx->mapping) {
+		dev_err(dev, "%s: Context is already mapped to an fd\n",
+			__func__);
+		rc = -EEXIST;
+		goto err1;
+	}
+
+	flags = O_RDWR | O_CLOEXEC;
+
+	/* This code is similar to anon_inode_getfd() */
+	rc = get_unused_fd_flags(flags);
+	if (unlikely(rc < 0)) {
+		dev_err(dev, "%s: get_unused_fd_flags failed rc=%d\n",
+			__func__, rc);
+		goto err1;
+	}
+	fdtmp = rc;
+
+	/* Patch the file ops that are not defined */
+	if (fops) {
+		PATCH_FOPS(poll);
+		PATCH_FOPS(read);
+		PATCH_FOPS(release);
+		PATCH_FOPS(mmap);
+	} else /* Use default ops */
+		fops = (struct file_operations *)&ocxl_afu_fops;
+
+	name = kasprintf(GFP_KERNEL, "ocxlflash:%d", ctx->pe);
+	file = ocxlflash_getfile(dev, name, fops, ctx, flags);
+	kfree(name);
+	if (IS_ERR(file)) {
+		rc = PTR_ERR(file);
+		dev_err(dev, "%s: ocxlflash_getfile failed rc=%d\n",
+			__func__, rc);
+		goto err2;
+	}
+
+	ctx->mapping = file->f_mapping;
+	*fd = fdtmp;
+out:
+	return file;
+err2:
+	put_unused_fd(fdtmp);
+err1:
+	file = ERR_PTR(rc);
+	goto out;
+}
+
+/**
+ * ocxlflash_fops_get_context() - get the context associated with the file
+ * @file:	File associated with the adapter context.
+ *
+ * Return: pointer to the context
+ */
+static void *ocxlflash_fops_get_context(struct file *file)
+{
+	return file->private_data;
+}
+
+/**
+ * ocxlflash_afu_irq() - interrupt handler for user contexts
+ * @irq:	Interrupt number.
+ * @data:	Private data provided at interrupt registration, the context.
+ *
+ * Return: Always return IRQ_HANDLED.
+ */
+static irqreturn_t ocxlflash_afu_irq(int irq, void *data)
+{
+	struct ocxlflash_context *ctx = data;
+	struct device *dev = ctx->hw_afu->dev;
+	int i;
+
+	dev_dbg(dev, "%s: Interrupt raised for pe %i virq %i\n",
+		__func__, ctx->pe, irq);
+
+	for (i = 0; i < ctx->num_irqs; i++) {
+		if (ctx->irqs[i].virq == irq)
+			break;
+	}
+	if (unlikely(i >= ctx->num_irqs)) {
+		dev_err(dev, "%s: Received AFU IRQ out of range\n", __func__);
+		goto out;
+	}
+
+	spin_lock(&ctx->slock);
+	set_bit(i - 1, &ctx->irq_bitmap);
+	ctx->pending_irq = true;
+	spin_unlock(&ctx->slock);
+
+	wake_up_all(&ctx->wq);
+out:
+	return IRQ_HANDLED;
+}
+
+/**
+ * ocxlflash_start_work() - start a user context
+ * @ctx_cookie:	Context to be started.
+ * @num_irqs:	Number of interrupts requested.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_start_work(void *ctx_cookie, u64 num_irqs)
+{
+	struct ocxlflash_context *ctx = ctx_cookie;
+	struct ocxl_hw_afu *afu = ctx->hw_afu;
+	struct device *dev = afu->dev;
+	char *name;
+	int rc = 0;
+	int i;
+
+	rc = alloc_afu_irqs(ctx, num_irqs);
+	if (unlikely(rc < 0)) {
+		dev_err(dev, "%s: alloc_afu_irqs failed rc=%d\n", __func__, rc);
+		goto out;
+	}
+
+	for (i = 0; i < num_irqs; i++) {
+		name = kasprintf(GFP_KERNEL, "ocxlflash-%s-pe%i-%i",
+				 dev_name(dev), ctx->pe, i);
+		rc = afu_map_irq(0, ctx, i, ocxlflash_afu_irq, ctx, name);
+		kfree(name);
+		if (unlikely(rc < 0)) {
+			dev_err(dev, "%s: afu_map_irq failed rc=%d\n",
+				__func__, rc);
+			goto err;
+		}
+	}
+
+	rc = start_context(ctx);
+	if (unlikely(rc)) {
+		dev_err(dev, "%s: start_context failed rc=%d\n", __func__, rc);
+		goto err;
+	}
+out:
+	return rc;
+err:
+	for (i = i-1; i >= 0; i--)
+		afu_unmap_irq(0, ctx, i, ctx);
+	free_afu_irqs(ctx);
+	goto out;
+};
+
+/**
+ * ocxlflash_fd_mmap() - mmap handler for adapter file descriptor
+ * @file:	File installed with adapter file descriptor.
+ * @vma:	VM area associated with mapping.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_fd_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	return afu_mmap(file, vma);
+}
+
+/**
+ * ocxlflash_fd_release() - release the context associated with the file
+ * @inode:	File inode pointer.
+ * @file:	File associated with the adapter context.
+ *
+ * Return: 0 on success, -errno on failure
+ */
+static int ocxlflash_fd_release(struct inode *inode, struct file *file)
+{
+	return afu_release(inode, file);
+}
+
+/* Backend ops to ocxlflash services */
+const struct cxlflash_backend_ops cxlflash_ocxl_ops = {
+	.module			= THIS_MODULE,
+	.psa_map		= ocxlflash_psa_map,
+	.psa_unmap		= ocxlflash_psa_unmap,
+	.process_element	= ocxlflash_process_element,
+	.map_afu_irq		= ocxlflash_map_afu_irq,
+	.unmap_afu_irq		= ocxlflash_unmap_afu_irq,
+	.get_irq_objhndl	= ocxlflash_get_irq_objhndl,
+	.start_context		= ocxlflash_start_context,
+	.stop_context		= ocxlflash_stop_context,
+	.afu_reset		= ocxlflash_afu_reset,
+	.set_master		= ocxlflash_set_master,
+	.get_context		= ocxlflash_get_context,
+	.dev_context_init	= ocxlflash_dev_context_init,
+	.release_context	= ocxlflash_release_context,
+	.perst_reloads_same_image = ocxlflash_perst_reloads_same_image,
+	.read_adapter_vpd	= ocxlflash_read_adapter_vpd,
+	.allocate_afu_irqs	= ocxlflash_allocate_afu_irqs,
+	.free_afu_irqs		= ocxlflash_free_afu_irqs,
+	.create_afu		= ocxlflash_create_afu,
+	.destroy_afu		= ocxlflash_destroy_afu,
+	.get_fd			= ocxlflash_get_fd,
+	.fops_get_context	= ocxlflash_fops_get_context,
+	.start_work		= ocxlflash_start_work,
+	.fd_mmap		= ocxlflash_fd_mmap,
+	.fd_release		= ocxlflash_fd_release,
+};