![Wei Yongjun](/assets/img/avatar_default.png)
Add the missing unlock before return from function
afu_ioctl_enable_p9_wait() in the error handling case.
Fixes: e948e06fc6
("ocxl: Expose the thread_id needed for wait on POWER9")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Reviewed-by: Alastair D'Silva <alastair@d-silva.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
542 lines
12 KiB
C
542 lines
12 KiB
C
// SPDX-License-Identifier: GPL-2.0+
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// Copyright 2017 IBM Corp.
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#include <linux/fs.h>
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#include <linux/poll.h>
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#include <linux/sched/signal.h>
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#include <linux/uaccess.h>
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#include <uapi/misc/ocxl.h>
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#include <asm/reg.h>
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#include <asm/switch_to.h>
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#include "ocxl_internal.h"
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#define OCXL_NUM_MINORS 256 /* Total to reserve */
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static dev_t ocxl_dev;
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static struct class *ocxl_class;
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static struct mutex minors_idr_lock;
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static struct idr minors_idr;
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static struct ocxl_afu *find_and_get_afu(dev_t devno)
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{
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struct ocxl_afu *afu;
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int afu_minor;
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afu_minor = MINOR(devno);
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/*
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* We don't declare an RCU critical section here, as our AFU
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* is protected by a reference counter on the device. By the time the
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* minor number of a device is removed from the idr, the ref count of
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* the device is already at 0, so no user API will access that AFU and
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* this function can't return it.
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*/
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afu = idr_find(&minors_idr, afu_minor);
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if (afu)
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ocxl_afu_get(afu);
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return afu;
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}
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static int allocate_afu_minor(struct ocxl_afu *afu)
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{
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int minor;
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mutex_lock(&minors_idr_lock);
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minor = idr_alloc(&minors_idr, afu, 0, OCXL_NUM_MINORS, GFP_KERNEL);
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mutex_unlock(&minors_idr_lock);
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return minor;
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}
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static void free_afu_minor(struct ocxl_afu *afu)
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{
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mutex_lock(&minors_idr_lock);
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idr_remove(&minors_idr, MINOR(afu->dev.devt));
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mutex_unlock(&minors_idr_lock);
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}
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static int afu_open(struct inode *inode, struct file *file)
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{
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struct ocxl_afu *afu;
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struct ocxl_context *ctx;
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int rc;
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pr_debug("%s for device %x\n", __func__, inode->i_rdev);
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afu = find_and_get_afu(inode->i_rdev);
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if (!afu)
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return -ENODEV;
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ctx = ocxl_context_alloc();
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if (!ctx) {
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rc = -ENOMEM;
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goto put_afu;
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}
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rc = ocxl_context_init(ctx, afu, inode->i_mapping);
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if (rc)
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goto put_afu;
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file->private_data = ctx;
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ocxl_afu_put(afu);
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return 0;
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put_afu:
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ocxl_afu_put(afu);
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return rc;
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}
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static long afu_ioctl_attach(struct ocxl_context *ctx,
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struct ocxl_ioctl_attach __user *uarg)
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{
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struct ocxl_ioctl_attach arg;
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u64 amr = 0;
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int rc;
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pr_debug("%s for context %d\n", __func__, ctx->pasid);
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if (copy_from_user(&arg, uarg, sizeof(arg)))
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return -EFAULT;
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/* Make sure reserved fields are not set for forward compatibility */
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if (arg.reserved1 || arg.reserved2 || arg.reserved3)
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return -EINVAL;
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amr = arg.amr & mfspr(SPRN_UAMOR);
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rc = ocxl_context_attach(ctx, amr);
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return rc;
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}
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static long afu_ioctl_get_metadata(struct ocxl_context *ctx,
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struct ocxl_ioctl_metadata __user *uarg)
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{
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struct ocxl_ioctl_metadata arg;
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memset(&arg, 0, sizeof(arg));
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arg.version = 0;
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arg.afu_version_major = ctx->afu->config.version_major;
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arg.afu_version_minor = ctx->afu->config.version_minor;
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arg.pasid = ctx->pasid;
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arg.pp_mmio_size = ctx->afu->config.pp_mmio_stride;
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arg.global_mmio_size = ctx->afu->config.global_mmio_size;
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if (copy_to_user(uarg, &arg, sizeof(arg)))
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return -EFAULT;
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return 0;
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}
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#ifdef CONFIG_PPC64
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static long afu_ioctl_enable_p9_wait(struct ocxl_context *ctx,
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struct ocxl_ioctl_p9_wait __user *uarg)
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{
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struct ocxl_ioctl_p9_wait arg;
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memset(&arg, 0, sizeof(arg));
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if (cpu_has_feature(CPU_FTR_P9_TIDR)) {
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enum ocxl_context_status status;
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// Locks both status & tidr
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mutex_lock(&ctx->status_mutex);
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if (!ctx->tidr) {
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if (set_thread_tidr(current)) {
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mutex_unlock(&ctx->status_mutex);
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return -ENOENT;
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}
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ctx->tidr = current->thread.tidr;
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}
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status = ctx->status;
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mutex_unlock(&ctx->status_mutex);
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if (status == ATTACHED) {
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int rc;
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struct link *link = ctx->afu->fn->link;
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rc = ocxl_link_update_pe(link, ctx->pasid, ctx->tidr);
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if (rc)
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return rc;
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}
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arg.thread_id = ctx->tidr;
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} else
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return -ENOENT;
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if (copy_to_user(uarg, &arg, sizeof(arg)))
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return -EFAULT;
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return 0;
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}
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#endif
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static long afu_ioctl_get_features(struct ocxl_context *ctx,
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struct ocxl_ioctl_features __user *uarg)
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{
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struct ocxl_ioctl_features arg;
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memset(&arg, 0, sizeof(arg));
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#ifdef CONFIG_PPC64
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if (cpu_has_feature(CPU_FTR_P9_TIDR))
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arg.flags[0] |= OCXL_IOCTL_FEATURES_FLAGS0_P9_WAIT;
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#endif
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if (copy_to_user(uarg, &arg, sizeof(arg)))
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return -EFAULT;
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return 0;
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}
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#define CMD_STR(x) (x == OCXL_IOCTL_ATTACH ? "ATTACH" : \
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x == OCXL_IOCTL_IRQ_ALLOC ? "IRQ_ALLOC" : \
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x == OCXL_IOCTL_IRQ_FREE ? "IRQ_FREE" : \
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x == OCXL_IOCTL_IRQ_SET_FD ? "IRQ_SET_FD" : \
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x == OCXL_IOCTL_GET_METADATA ? "GET_METADATA" : \
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x == OCXL_IOCTL_ENABLE_P9_WAIT ? "ENABLE_P9_WAIT" : \
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x == OCXL_IOCTL_GET_FEATURES ? "GET_FEATURES" : \
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"UNKNOWN")
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static long afu_ioctl(struct file *file, unsigned int cmd,
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unsigned long args)
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{
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struct ocxl_context *ctx = file->private_data;
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struct ocxl_ioctl_irq_fd irq_fd;
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u64 irq_offset;
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long rc;
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pr_debug("%s for context %d, command %s\n", __func__, ctx->pasid,
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CMD_STR(cmd));
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if (ctx->status == CLOSED)
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return -EIO;
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switch (cmd) {
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case OCXL_IOCTL_ATTACH:
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rc = afu_ioctl_attach(ctx,
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(struct ocxl_ioctl_attach __user *) args);
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break;
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case OCXL_IOCTL_IRQ_ALLOC:
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rc = ocxl_afu_irq_alloc(ctx, &irq_offset);
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if (!rc) {
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rc = copy_to_user((u64 __user *) args, &irq_offset,
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sizeof(irq_offset));
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if (rc) {
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ocxl_afu_irq_free(ctx, irq_offset);
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return -EFAULT;
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}
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}
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break;
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case OCXL_IOCTL_IRQ_FREE:
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rc = copy_from_user(&irq_offset, (u64 __user *) args,
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sizeof(irq_offset));
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if (rc)
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return -EFAULT;
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rc = ocxl_afu_irq_free(ctx, irq_offset);
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break;
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case OCXL_IOCTL_IRQ_SET_FD:
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rc = copy_from_user(&irq_fd, (u64 __user *) args,
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sizeof(irq_fd));
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if (rc)
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return -EFAULT;
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if (irq_fd.reserved)
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return -EINVAL;
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rc = ocxl_afu_irq_set_fd(ctx, irq_fd.irq_offset,
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irq_fd.eventfd);
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break;
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case OCXL_IOCTL_GET_METADATA:
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rc = afu_ioctl_get_metadata(ctx,
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(struct ocxl_ioctl_metadata __user *) args);
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break;
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#ifdef CONFIG_PPC64
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case OCXL_IOCTL_ENABLE_P9_WAIT:
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rc = afu_ioctl_enable_p9_wait(ctx,
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(struct ocxl_ioctl_p9_wait __user *) args);
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break;
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#endif
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case OCXL_IOCTL_GET_FEATURES:
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rc = afu_ioctl_get_features(ctx,
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(struct ocxl_ioctl_features __user *) args);
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break;
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default:
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rc = -EINVAL;
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}
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return rc;
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}
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static long afu_compat_ioctl(struct file *file, unsigned int cmd,
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unsigned long args)
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{
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return afu_ioctl(file, cmd, args);
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}
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static int afu_mmap(struct file *file, struct vm_area_struct *vma)
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{
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struct ocxl_context *ctx = file->private_data;
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pr_debug("%s for context %d\n", __func__, ctx->pasid);
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return ocxl_context_mmap(ctx, vma);
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}
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static bool has_xsl_error(struct ocxl_context *ctx)
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{
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bool ret;
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mutex_lock(&ctx->xsl_error_lock);
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ret = !!ctx->xsl_error.addr;
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mutex_unlock(&ctx->xsl_error_lock);
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return ret;
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}
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/*
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* Are there any events pending on the AFU
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* ctx: The AFU context
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* Returns: true if there are events pending
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*/
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static bool afu_events_pending(struct ocxl_context *ctx)
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{
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if (has_xsl_error(ctx))
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return true;
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return false;
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}
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static unsigned int afu_poll(struct file *file, struct poll_table_struct *wait)
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{
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struct ocxl_context *ctx = file->private_data;
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unsigned int mask = 0;
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bool closed;
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pr_debug("%s for context %d\n", __func__, ctx->pasid);
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poll_wait(file, &ctx->events_wq, wait);
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mutex_lock(&ctx->status_mutex);
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closed = (ctx->status == CLOSED);
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mutex_unlock(&ctx->status_mutex);
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if (afu_events_pending(ctx))
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mask = EPOLLIN | EPOLLRDNORM;
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else if (closed)
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mask = EPOLLERR;
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return mask;
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}
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/*
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* Populate the supplied buffer with a single XSL error
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* ctx: The AFU context to report the error from
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* header: the event header to populate
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* buf: The buffer to write the body into (should be at least
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* AFU_EVENT_BODY_XSL_ERROR_SIZE)
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* Return: the amount of buffer that was populated
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*/
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static ssize_t append_xsl_error(struct ocxl_context *ctx,
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struct ocxl_kernel_event_header *header,
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char __user *buf)
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{
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struct ocxl_kernel_event_xsl_fault_error body;
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memset(&body, 0, sizeof(body));
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mutex_lock(&ctx->xsl_error_lock);
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if (!ctx->xsl_error.addr) {
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mutex_unlock(&ctx->xsl_error_lock);
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return 0;
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}
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body.addr = ctx->xsl_error.addr;
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body.dsisr = ctx->xsl_error.dsisr;
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body.count = ctx->xsl_error.count;
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ctx->xsl_error.addr = 0;
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ctx->xsl_error.dsisr = 0;
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ctx->xsl_error.count = 0;
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mutex_unlock(&ctx->xsl_error_lock);
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header->type = OCXL_AFU_EVENT_XSL_FAULT_ERROR;
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if (copy_to_user(buf, &body, sizeof(body)))
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return -EFAULT;
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return sizeof(body);
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}
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#define AFU_EVENT_BODY_MAX_SIZE sizeof(struct ocxl_kernel_event_xsl_fault_error)
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/*
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* Reports events on the AFU
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* Format:
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* Header (struct ocxl_kernel_event_header)
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* Body (struct ocxl_kernel_event_*)
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* Header...
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*/
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static ssize_t afu_read(struct file *file, char __user *buf, size_t count,
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loff_t *off)
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{
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struct ocxl_context *ctx = file->private_data;
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struct ocxl_kernel_event_header header;
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ssize_t rc;
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ssize_t used = 0;
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DEFINE_WAIT(event_wait);
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memset(&header, 0, sizeof(header));
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/* Require offset to be 0 */
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if (*off != 0)
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return -EINVAL;
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if (count < (sizeof(struct ocxl_kernel_event_header) +
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AFU_EVENT_BODY_MAX_SIZE))
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return -EINVAL;
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for (;;) {
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prepare_to_wait(&ctx->events_wq, &event_wait,
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TASK_INTERRUPTIBLE);
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if (afu_events_pending(ctx))
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break;
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if (ctx->status == CLOSED)
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break;
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if (file->f_flags & O_NONBLOCK) {
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finish_wait(&ctx->events_wq, &event_wait);
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return -EAGAIN;
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}
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if (signal_pending(current)) {
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finish_wait(&ctx->events_wq, &event_wait);
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return -ERESTARTSYS;
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}
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schedule();
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}
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finish_wait(&ctx->events_wq, &event_wait);
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if (has_xsl_error(ctx)) {
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used = append_xsl_error(ctx, &header, buf + sizeof(header));
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if (used < 0)
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return used;
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}
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if (!afu_events_pending(ctx))
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header.flags |= OCXL_KERNEL_EVENT_FLAG_LAST;
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if (copy_to_user(buf, &header, sizeof(header)))
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return -EFAULT;
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used += sizeof(header);
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rc = used;
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return rc;
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}
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static int afu_release(struct inode *inode, struct file *file)
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{
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struct ocxl_context *ctx = file->private_data;
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int rc;
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pr_debug("%s for device %x\n", __func__, inode->i_rdev);
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rc = ocxl_context_detach(ctx);
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mutex_lock(&ctx->mapping_lock);
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ctx->mapping = NULL;
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mutex_unlock(&ctx->mapping_lock);
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wake_up_all(&ctx->events_wq);
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if (rc != -EBUSY)
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ocxl_context_free(ctx);
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return 0;
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}
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static const struct file_operations ocxl_afu_fops = {
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.owner = THIS_MODULE,
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.open = afu_open,
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.unlocked_ioctl = afu_ioctl,
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.compat_ioctl = afu_compat_ioctl,
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.mmap = afu_mmap,
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.poll = afu_poll,
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.read = afu_read,
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.release = afu_release,
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};
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int ocxl_create_cdev(struct ocxl_afu *afu)
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{
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int rc;
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cdev_init(&afu->cdev, &ocxl_afu_fops);
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rc = cdev_add(&afu->cdev, afu->dev.devt, 1);
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if (rc) {
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dev_err(&afu->dev, "Unable to add afu char device: %d\n", rc);
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return rc;
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}
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return 0;
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}
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void ocxl_destroy_cdev(struct ocxl_afu *afu)
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{
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cdev_del(&afu->cdev);
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}
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int ocxl_register_afu(struct ocxl_afu *afu)
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{
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int minor;
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minor = allocate_afu_minor(afu);
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if (minor < 0)
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return minor;
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afu->dev.devt = MKDEV(MAJOR(ocxl_dev), minor);
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afu->dev.class = ocxl_class;
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return device_register(&afu->dev);
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}
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void ocxl_unregister_afu(struct ocxl_afu *afu)
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{
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free_afu_minor(afu);
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}
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static char *ocxl_devnode(struct device *dev, umode_t *mode)
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{
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return kasprintf(GFP_KERNEL, "ocxl/%s", dev_name(dev));
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}
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int ocxl_file_init(void)
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{
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int rc;
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mutex_init(&minors_idr_lock);
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idr_init(&minors_idr);
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rc = alloc_chrdev_region(&ocxl_dev, 0, OCXL_NUM_MINORS, "ocxl");
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if (rc) {
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pr_err("Unable to allocate ocxl major number: %d\n", rc);
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return rc;
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}
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ocxl_class = class_create(THIS_MODULE, "ocxl");
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if (IS_ERR(ocxl_class)) {
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pr_err("Unable to create ocxl class\n");
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unregister_chrdev_region(ocxl_dev, OCXL_NUM_MINORS);
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return PTR_ERR(ocxl_class);
|
|
}
|
|
|
|
ocxl_class->devnode = ocxl_devnode;
|
|
return 0;
|
|
}
|
|
|
|
void ocxl_file_exit(void)
|
|
{
|
|
class_destroy(ocxl_class);
|
|
unregister_chrdev_region(ocxl_dev, OCXL_NUM_MINORS);
|
|
idr_destroy(&minors_idr);
|
|
}
|