From e636c8d336489bf3eed5878299e6cc045bbad077 Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Tue, 20 Feb 2024 01:17:29 +0000
Subject: [PATCH] debug lk
---
kernel/drivers/vfio/pci/vfio_pci_rdwr.c | 162 +++++++++++++++++++++++++++++++++++++++++++-----------
1 files changed, 129 insertions(+), 33 deletions(-)
diff --git a/kernel/drivers/vfio/pci/vfio_pci_rdwr.c b/kernel/drivers/vfio/pci/vfio_pci_rdwr.c
index 3d0ec2b..a0b5fc8 100644
--- a/kernel/drivers/vfio/pci/vfio_pci_rdwr.c
+++ b/kernel/drivers/vfio/pci/vfio_pci_rdwr.c
@@ -1,12 +1,9 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* VFIO PCI I/O Port & MMIO access
*
* Copyright (C) 2012 Red Hat, Inc. All rights reserved.
* Author: Alex Williamson <alex.williamson@redhat.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
*
* Derived from original vfio:
* Copyright 2010 Cisco Systems, Inc. All rights reserved.
@@ -40,17 +37,70 @@
#define vfio_ioread8 ioread8
#define vfio_iowrite8 iowrite8
+#define VFIO_IOWRITE(size) \
+static int vfio_pci_iowrite##size(struct vfio_pci_device *vdev, \
+ bool test_mem, u##size val, void __iomem *io) \
+{ \
+ if (test_mem) { \
+ down_read(&vdev->memory_lock); \
+ if (!__vfio_pci_memory_enabled(vdev)) { \
+ up_read(&vdev->memory_lock); \
+ return -EIO; \
+ } \
+ } \
+ \
+ vfio_iowrite##size(val, io); \
+ \
+ if (test_mem) \
+ up_read(&vdev->memory_lock); \
+ \
+ return 0; \
+}
+
+VFIO_IOWRITE(8)
+VFIO_IOWRITE(16)
+VFIO_IOWRITE(32)
+#ifdef iowrite64
+VFIO_IOWRITE(64)
+#endif
+
+#define VFIO_IOREAD(size) \
+static int vfio_pci_ioread##size(struct vfio_pci_device *vdev, \
+ bool test_mem, u##size *val, void __iomem *io) \
+{ \
+ if (test_mem) { \
+ down_read(&vdev->memory_lock); \
+ if (!__vfio_pci_memory_enabled(vdev)) { \
+ up_read(&vdev->memory_lock); \
+ return -EIO; \
+ } \
+ } \
+ \
+ *val = vfio_ioread##size(io); \
+ \
+ if (test_mem) \
+ up_read(&vdev->memory_lock); \
+ \
+ return 0; \
+}
+
+VFIO_IOREAD(8)
+VFIO_IOREAD(16)
+VFIO_IOREAD(32)
+
/*
* Read or write from an __iomem region (MMIO or I/O port) with an excluded
* range which is inaccessible. The excluded range drops writes and fills
* reads with -1. This is intended for handling MSI-X vector tables and
* leftover space for ROM BARs.
*/
-static ssize_t do_io_rw(void __iomem *io, char __user *buf,
+static ssize_t do_io_rw(struct vfio_pci_device *vdev, bool test_mem,
+ void __iomem *io, char __user *buf,
loff_t off, size_t count, size_t x_start,
size_t x_end, bool iswrite)
{
ssize_t done = 0;
+ int ret;
while (count) {
size_t fillable, filled;
@@ -69,9 +119,15 @@
if (copy_from_user(&val, buf, 4))
return -EFAULT;
- vfio_iowrite32(val, io + off);
+ ret = vfio_pci_iowrite32(vdev, test_mem,
+ val, io + off);
+ if (ret)
+ return ret;
} else {
- val = vfio_ioread32(io + off);
+ ret = vfio_pci_ioread32(vdev, test_mem,
+ &val, io + off);
+ if (ret)
+ return ret;
if (copy_to_user(buf, &val, 4))
return -EFAULT;
@@ -85,9 +141,15 @@
if (copy_from_user(&val, buf, 2))
return -EFAULT;
- vfio_iowrite16(val, io + off);
+ ret = vfio_pci_iowrite16(vdev, test_mem,
+ val, io + off);
+ if (ret)
+ return ret;
} else {
- val = vfio_ioread16(io + off);
+ ret = vfio_pci_ioread16(vdev, test_mem,
+ &val, io + off);
+ if (ret)
+ return ret;
if (copy_to_user(buf, &val, 2))
return -EFAULT;
@@ -101,9 +163,15 @@
if (copy_from_user(&val, buf, 1))
return -EFAULT;
- vfio_iowrite8(val, io + off);
+ ret = vfio_pci_iowrite8(vdev, test_mem,
+ val, io + off);
+ if (ret)
+ return ret;
} else {
- val = vfio_ioread8(io + off);
+ ret = vfio_pci_ioread8(vdev, test_mem,
+ &val, io + off);
+ if (ret)
+ return ret;
if (copy_to_user(buf, &val, 1))
return -EFAULT;
@@ -181,14 +249,6 @@
count = min(count, (size_t)(end - pos));
- if (res->flags & IORESOURCE_MEM) {
- down_read(&vdev->memory_lock);
- if (!__vfio_pci_memory_enabled(vdev)) {
- up_read(&vdev->memory_lock);
- return -EIO;
- }
- }
-
if (bar == PCI_ROM_RESOURCE) {
/*
* The ROM can fill less space than the BAR, so we start the
@@ -216,7 +276,8 @@
x_end = vdev->msix_offset + vdev->msix_size;
}
- done = do_io_rw(io, buf, pos, count, x_start, x_end, iswrite);
+ done = do_io_rw(vdev, res->flags & IORESOURCE_MEM, io, buf, pos,
+ count, x_start, x_end, iswrite);
if (done >= 0)
*ppos += done;
@@ -224,9 +285,6 @@
if (bar == PCI_ROM_RESOURCE)
pci_unmap_rom(pdev, io);
out:
- if (res->flags & IORESOURCE_MEM)
- up_read(&vdev->memory_lock);
-
return done;
}
@@ -249,7 +307,7 @@
switch ((u32)pos) {
case 0xa0000 ... 0xbffff:
count = min(count, (size_t)(0xc0000 - pos));
- iomem = ioremap_nocache(0xa0000, 0xbffff - 0xa0000 + 1);
+ iomem = ioremap(0xa0000, 0xbffff - 0xa0000 + 1);
off = pos - 0xa0000;
rsrc = VGA_RSRC_LEGACY_MEM;
is_ioport = false;
@@ -281,7 +339,12 @@
return ret;
}
- done = do_io_rw(iomem, buf, off, count, 0, 0, iswrite);
+ /*
+ * VGA MMIO is a legacy, non-BAR resource that hopefully allows
+ * probing, so we don't currently worry about access in relation
+ * to the memory enable bit in the command register.
+ */
+ done = do_io_rw(vdev, false, iomem, buf, off, count, 0, 0, iswrite);
vga_put(vdev->pdev, rsrc);
@@ -293,28 +356,58 @@
return done;
}
-static int vfio_pci_ioeventfd_handler(void *opaque, void *unused)
+static void vfio_pci_ioeventfd_do_write(struct vfio_pci_ioeventfd *ioeventfd,
+ bool test_mem)
{
- struct vfio_pci_ioeventfd *ioeventfd = opaque;
-
switch (ioeventfd->count) {
case 1:
- vfio_iowrite8(ioeventfd->data, ioeventfd->addr);
+ vfio_pci_iowrite8(ioeventfd->vdev, test_mem,
+ ioeventfd->data, ioeventfd->addr);
break;
case 2:
- vfio_iowrite16(ioeventfd->data, ioeventfd->addr);
+ vfio_pci_iowrite16(ioeventfd->vdev, test_mem,
+ ioeventfd->data, ioeventfd->addr);
break;
case 4:
- vfio_iowrite32(ioeventfd->data, ioeventfd->addr);
+ vfio_pci_iowrite32(ioeventfd->vdev, test_mem,
+ ioeventfd->data, ioeventfd->addr);
break;
#ifdef iowrite64
case 8:
- vfio_iowrite64(ioeventfd->data, ioeventfd->addr);
+ vfio_pci_iowrite64(ioeventfd->vdev, test_mem,
+ ioeventfd->data, ioeventfd->addr);
break;
#endif
}
+}
+
+static int vfio_pci_ioeventfd_handler(void *opaque, void *unused)
+{
+ struct vfio_pci_ioeventfd *ioeventfd = opaque;
+ struct vfio_pci_device *vdev = ioeventfd->vdev;
+
+ if (ioeventfd->test_mem) {
+ if (!down_read_trylock(&vdev->memory_lock))
+ return 1; /* Lock contended, use thread */
+ if (!__vfio_pci_memory_enabled(vdev)) {
+ up_read(&vdev->memory_lock);
+ return 0;
+ }
+ }
+
+ vfio_pci_ioeventfd_do_write(ioeventfd, false);
+
+ if (ioeventfd->test_mem)
+ up_read(&vdev->memory_lock);
return 0;
+}
+
+static void vfio_pci_ioeventfd_thread(void *opaque, void *unused)
+{
+ struct vfio_pci_ioeventfd *ioeventfd = opaque;
+
+ vfio_pci_ioeventfd_do_write(ioeventfd, ioeventfd->test_mem);
}
long vfio_pci_ioeventfd(struct vfio_pci_device *vdev, loff_t offset,
@@ -381,14 +474,17 @@
goto out_unlock;
}
+ ioeventfd->vdev = vdev;
ioeventfd->addr = vdev->barmap[bar] + pos;
ioeventfd->data = data;
ioeventfd->pos = pos;
ioeventfd->bar = bar;
ioeventfd->count = count;
+ ioeventfd->test_mem = vdev->pdev->resource[bar].flags & IORESOURCE_MEM;
ret = vfio_virqfd_enable(ioeventfd, vfio_pci_ioeventfd_handler,
- NULL, NULL, &ioeventfd->virqfd, fd);
+ vfio_pci_ioeventfd_thread, NULL,
+ &ioeventfd->virqfd, fd);
if (ret) {
kfree(ioeventfd);
goto out_unlock;
--
Gitblit v1.6.2