Add these helpers that access config space and return an -errno style
return.
Signed-off-by: John Levon <john.le...@nutanix.com>
---
hw/vfio/pci.c | 123 ++++++++++++++++++++++++++++++++------------------
1 file changed, 80 insertions(+), 43 deletions(-)
diff --git a/hw/vfio/pci.c b/hw/vfio/pci.c
index 768c48d7ad..8455010d62 100644
--- a/hw/vfio/pci.c
+++ b/hw/vfio/pci.c
@@ -967,6 +967,28 @@ static void vfio_pci_load_rom(VFIOPCIDevice *vdev)
}
}
+/* "Raw" read of underlying config space. */
+static int vfio_pci_config_space_read(VFIOPCIDevice *vdev, off_t offset,
+ uint32_t size, void *data)
+{
+ ssize_t ret;
+
+ ret = pread(vdev->vbasedev.fd, data, size, vdev->config_offset + offset);
+
+ return ret < 0 ? -errno : (int)ret;
+}
+
+/* "Raw" write of underlying config space. */
+static int vfio_pci_config_space_write(VFIOPCIDevice *vdev, off_t offset,
+ uint32_t size, void *data)
+{
+ ssize_t ret;
+
+ ret = pwrite(vdev->vbasedev.fd, data, size, vdev->config_offset + offset);
+
+ return ret < 0 ? -errno : (int)ret;
+}
+
static uint64_t vfio_rom_read(void *opaque, hwaddr addr, unsigned size)
{
VFIOPCIDevice *vdev = opaque;
@@ -1019,10 +1041,9 @@ static const MemoryRegionOps vfio_rom_ops = {
static void vfio_pci_size_rom(VFIOPCIDevice *vdev)
{
+ VFIODevice *vbasedev = &vdev->vbasedev;
uint32_t orig, size = cpu_to_le32((uint32_t)PCI_ROM_ADDRESS_MASK);
- off_t offset = vdev->config_offset + PCI_ROM_ADDRESS;
char *name;
- int fd = vdev->vbasedev.fd;
if (vdev->pdev.romfile || !vdev->pdev.rom_bar) {
/* Since pci handles romfile, just print a message and return */
@@ -1039,11 +1060,12 @@ static void vfio_pci_size_rom(VFIOPCIDevice *vdev)
* Use the same size ROM BAR as the physical device. The contents
* will get filled in later when the guest tries to read it.
*/
- if (pread(fd, &orig, 4, offset) != 4 ||
- pwrite(fd, &size, 4, offset) != 4 ||
- pread(fd, &size, 4, offset) != 4 ||
- pwrite(fd, &orig, 4, offset) != 4) {
- error_report("%s(%s) failed: %m", __func__, vdev->vbasedev.name);
+ if (vfio_pci_config_space_read(vdev, PCI_ROM_ADDRESS, 4, &orig) != 4 ||
+ vfio_pci_config_space_write(vdev, PCI_ROM_ADDRESS, 4, &size) != 4 ||
+ vfio_pci_config_space_read(vdev, PCI_ROM_ADDRESS, 4, &size) != 4 ||
+ vfio_pci_config_space_write(vdev, PCI_ROM_ADDRESS, 4, &orig) != 4) {
+
+ error_report("%s(%s) ROM access failed", __func__, vbasedev->name);
return;
}
@@ -1223,6 +1245,7 @@ static void vfio_sub_page_bar_update_mapping(PCIDevice
*pdev, int bar)
uint32_t vfio_pci_read_config(PCIDevice *pdev, uint32_t addr, int len)
{
VFIOPCIDevice *vdev = VFIO_PCI(pdev);
+ VFIODevice *vbasedev = &vdev->vbasedev;
uint32_t emu_bits = 0, emu_val = 0, phys_val = 0, val;
memcpy(&emu_bits, vdev->emulated_config_bits + addr, len);
@@ -1235,12 +1258,12 @@ uint32_t vfio_pci_read_config(PCIDevice *pdev, uint32_t
addr, int len)
if (~emu_bits & (0xffffffffU >> (32 - len * 8))) {
ssize_t ret;
- ret = pread(vdev->vbasedev.fd, &phys_val, len,
- vdev->config_offset + addr);
+ ret = vfio_pci_config_space_read(vdev, addr, len, &phys_val);
if (ret != len) {
- error_report("%s(%s, 0x%x, 0x%x) failed: %m",
- __func__, vdev->vbasedev.name, addr, len);
- return -errno;
+ error_report("%s(%s, 0x%x, 0x%x) failed: %s",
+ __func__, vbasedev->name, addr, len,
+ strreaderror(ret));
+ return -1;
}
phys_val = le32_to_cpu(phys_val);
}
@@ -1256,15 +1279,18 @@ void vfio_pci_write_config(PCIDevice *pdev,
uint32_t addr, uint32_t val, int len)
{
VFIOPCIDevice *vdev = VFIO_PCI(pdev);
+ VFIODevice *vbasedev = &vdev->vbasedev;
uint32_t val_le = cpu_to_le32(val);
+ int ret;
trace_vfio_pci_write_config(vdev->vbasedev.name, addr, val, len);
/* Write everything to VFIO, let it filter out what we can't write */
- if (pwrite(vdev->vbasedev.fd, &val_le, len, vdev->config_offset + addr)
- != len) {
- error_report("%s(%s, 0x%x, 0x%x, 0x%x) failed: %m",
- __func__, vdev->vbasedev.name, addr, val, len);
+ ret = vfio_pci_config_space_write(vdev, addr, len, &val_le);
+ if (ret != len) {
+ error_report("%s(%s, 0x%x, 0x%x, 0x%x) failed: %s",
+ __func__, vbasedev->name, addr, val, len,
+ strwriteerror(ret));
}
/* MSI/MSI-X Enabling/Disabling */
@@ -1352,9 +1378,11 @@ static bool vfio_msi_setup(VFIOPCIDevice *vdev, int pos,
Error **errp)
int ret, entries;
Error *err = NULL;
- if (pread(vdev->vbasedev.fd, &ctrl, sizeof(ctrl),
- vdev->config_offset + pos + PCI_CAP_FLAGS) != sizeof(ctrl)) {
- error_setg_errno(errp, errno, "failed reading MSI PCI_CAP_FLAGS");
+ ret = vfio_pci_config_space_read(vdev, pos + PCI_CAP_FLAGS,
+ sizeof(ctrl), &ctrl);
+ if (ret != sizeof(ctrl)) {
+ error_setg(errp, "failed reading MSI PCI_CAP_FLAGS: %s",
+ strreaderror(ret));
return false;
}
ctrl = le16_to_cpu(ctrl);
@@ -1561,30 +1589,35 @@ static bool vfio_msix_early_setup(VFIOPCIDevice *vdev,
Error **errp)
uint8_t pos;
uint16_t ctrl;
uint32_t table, pba;
- int ret, fd = vdev->vbasedev.fd;
struct vfio_irq_info irq_info;
VFIOMSIXInfo *msix;
+ int ret;
pos = pci_find_capability(&vdev->pdev, PCI_CAP_ID_MSIX);
if (!pos) {
return true;
}
- if (pread(fd, &ctrl, sizeof(ctrl),
- vdev->config_offset + pos + PCI_MSIX_FLAGS) != sizeof(ctrl)) {
- error_setg_errno(errp, errno, "failed to read PCI MSIX FLAGS");
+ ret = vfio_pci_config_space_read(vdev, pos + PCI_MSIX_FLAGS,
+ sizeof(ctrl), &ctrl);
+ if (ret != sizeof(ctrl)) {
+ error_setg(errp, "failed to read PCI MSIX FLAGS: %s",
+ strreaderror(ret));
return false;
}
- if (pread(fd, &table, sizeof(table),
- vdev->config_offset + pos + PCI_MSIX_TABLE) != sizeof(table)) {
- error_setg_errno(errp, errno, "failed to read PCI MSIX TABLE");
+ ret = vfio_pci_config_space_read(vdev, pos + PCI_MSIX_TABLE,
+ sizeof(table), &table);
+ if (ret != sizeof(table)) {
+ error_setg(errp, "failed to read PCI MSIX TABLE: %s",
+ strreaderror(ret));
return false;
}
- if (pread(fd, &pba, sizeof(pba),
- vdev->config_offset + pos + PCI_MSIX_PBA) != sizeof(pba)) {
- error_setg_errno(errp, errno, "failed to read PCI MSIX PBA");
+ ret = vfio_pci_config_space_read(vdev, pos + PCI_MSIX_PBA,
+ sizeof(pba), &pba);
+ if (ret != sizeof(pba)) {
+ error_setg(errp, "failed to read PCI MSIX PBA: %s", strreaderror(ret));
return false;
}
@@ -1744,10 +1777,10 @@ static void vfio_bar_prepare(VFIOPCIDevice *vdev, int
nr)
}
/* Determine what type of BAR this is for registration */
- ret = pread(vdev->vbasedev.fd, &pci_bar, sizeof(pci_bar),
- vdev->config_offset + PCI_BASE_ADDRESS_0 + (4 * nr));
+ ret = vfio_pci_config_space_read(vdev, PCI_BASE_ADDRESS_0 + (4 * nr),
+ sizeof(pci_bar), &pci_bar);
if (ret != sizeof(pci_bar)) {
- error_report("vfio: Failed to read BAR %d (%m)", nr);
+ error_report("vfio: Failed to read BAR %d: %s", nr, strreaderror(ret));
return;
}
@@ -2450,21 +2483,23 @@ void vfio_pci_pre_reset(VFIOPCIDevice *vdev)
void vfio_pci_post_reset(VFIOPCIDevice *vdev)
{
+ VFIODevice *vbasedev = &vdev->vbasedev;
Error *err = NULL;
- int nr;
+ int ret, nr;
if (!vfio_intx_enable(vdev, &err)) {
error_reportf_err(err, VFIO_MSG_PREFIX, vdev->vbasedev.name);
}
for (nr = 0; nr < PCI_NUM_REGIONS - 1; ++nr) {
- off_t addr = vdev->config_offset + PCI_BASE_ADDRESS_0 + (4 * nr);
+ off_t addr = PCI_BASE_ADDRESS_0 + (4 * nr);
uint32_t val = 0;
uint32_t len = sizeof(val);
- if (pwrite(vdev->vbasedev.fd, &val, len, addr) != len) {
- error_report("%s(%s) reset bar %d failed: %m", __func__,
- vdev->vbasedev.name, nr);
+ ret = vfio_pci_config_space_write(vdev, addr, len, &val);
+ if (ret != len) {
+ error_report("%s(%s) reset bar %d failed: %s", __func__,
+ vbasedev->name, nr, strwriteerror(ret));
}
}
@@ -3101,6 +3136,7 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
int i, ret;
char uuid[UUID_STR_LEN];
g_autofree char *name = NULL;
+ uint32_t config_space_size;
if (vbasedev->fd < 0 && !vbasedev->sysfsdev) {
if (!(~vdev->host.domain || ~vdev->host.bus ||
@@ -3155,13 +3191,14 @@ static void vfio_realize(PCIDevice *pdev, Error **errp)
goto error;
}
+ config_space_size = MIN(pci_config_size(&vdev->pdev), vdev->config_size);
+
/* Get a copy of config space */
- ret = pread(vbasedev->fd, vdev->pdev.config,
- MIN(pci_config_size(&vdev->pdev), vdev->config_size),
- vdev->config_offset);
- if (ret < (int)MIN(pci_config_size(&vdev->pdev), vdev->config_size)) {
- ret = ret < 0 ? -errno : -EFAULT;
- error_setg_errno(errp, -ret, "failed to read device config space");
+ ret = vfio_pci_config_space_read(vdev, 0, config_space_size,
+ vdev->pdev.config);
+ if (ret < (int)config_space_size) {
+ ret = ret < 0 ? -ret : EFAULT;
+ error_setg_errno(errp, ret, "failed to read device config space");
goto error;
}
--
2.43.0
