qemu/hw/xen/xen-host-pci-device.c
Konrad Rzeszutek Wilk bce3394817 xen/pt: Make xen_pt_unregister_device idempotent
To deal with xen_host_pci_[set|get]_ functions returning error values
and clearing ourselves in the init function we should make the
.exit (xen_pt_unregister_device) function be idempotent in case
the generic code starts calling .exit (or for fun does it before
calling .init!).

Reviewed-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
2015-09-10 16:47:20 +00:00

407 lines
9.8 KiB
C

/*
* Copyright (C) 2011 Citrix Ltd.
*
* This work is licensed under the terms of the GNU GPL, version 2. See
* the COPYING file in the top-level directory.
*
*/
#include "qemu-common.h"
#include "xen-host-pci-device.h"
#define XEN_HOST_PCI_MAX_EXT_CAP \
((PCIE_CONFIG_SPACE_SIZE - PCI_CONFIG_SPACE_SIZE) / (PCI_CAP_SIZEOF + 4))
#ifdef XEN_HOST_PCI_DEVICE_DEBUG
# define XEN_HOST_PCI_LOG(f, a...) fprintf(stderr, "%s: " f, __func__, ##a)
#else
# define XEN_HOST_PCI_LOG(f, a...) (void)0
#endif
/*
* from linux/ioport.h
* IO resources have these defined flags.
*/
#define IORESOURCE_BITS 0x000000ff /* Bus-specific bits */
#define IORESOURCE_TYPE_BITS 0x00000f00 /* Resource type */
#define IORESOURCE_IO 0x00000100
#define IORESOURCE_MEM 0x00000200
#define IORESOURCE_PREFETCH 0x00001000 /* No side effects */
#define IORESOURCE_MEM_64 0x00100000
static int xen_host_pci_sysfs_path(const XenHostPCIDevice *d,
const char *name, char *buf, ssize_t size)
{
int rc;
rc = snprintf(buf, size, "/sys/bus/pci/devices/%04x:%02x:%02x.%d/%s",
d->domain, d->bus, d->dev, d->func, name);
if (rc >= size || rc < 0) {
/* The ouput is truncated or an other error is encountered */
return -ENODEV;
}
return 0;
}
/* This size should be enough to read the first 7 lines of a resource file */
#define XEN_HOST_PCI_RESOURCE_BUFFER_SIZE 400
static int xen_host_pci_get_resource(XenHostPCIDevice *d)
{
int i, rc, fd;
char path[PATH_MAX];
char buf[XEN_HOST_PCI_RESOURCE_BUFFER_SIZE];
unsigned long long start, end, flags, size;
char *endptr, *s;
uint8_t type;
rc = xen_host_pci_sysfs_path(d, "resource", path, sizeof (path));
if (rc) {
return rc;
}
fd = open(path, O_RDONLY);
if (fd == -1) {
XEN_HOST_PCI_LOG("Error: Can't open %s: %s\n", path, strerror(errno));
return -errno;
}
do {
rc = read(fd, &buf, sizeof (buf) - 1);
if (rc < 0 && errno != EINTR) {
rc = -errno;
goto out;
}
} while (rc < 0);
buf[rc] = 0;
rc = 0;
s = buf;
for (i = 0; i < PCI_NUM_REGIONS; i++) {
type = 0;
start = strtoll(s, &endptr, 16);
if (*endptr != ' ' || s == endptr) {
break;
}
s = endptr + 1;
end = strtoll(s, &endptr, 16);
if (*endptr != ' ' || s == endptr) {
break;
}
s = endptr + 1;
flags = strtoll(s, &endptr, 16);
if (*endptr != '\n' || s == endptr) {
break;
}
s = endptr + 1;
if (start) {
size = end - start + 1;
} else {
size = 0;
}
if (flags & IORESOURCE_IO) {
type |= XEN_HOST_PCI_REGION_TYPE_IO;
}
if (flags & IORESOURCE_MEM) {
type |= XEN_HOST_PCI_REGION_TYPE_MEM;
}
if (flags & IORESOURCE_PREFETCH) {
type |= XEN_HOST_PCI_REGION_TYPE_PREFETCH;
}
if (flags & IORESOURCE_MEM_64) {
type |= XEN_HOST_PCI_REGION_TYPE_MEM_64;
}
if (i < PCI_ROM_SLOT) {
d->io_regions[i].base_addr = start;
d->io_regions[i].size = size;
d->io_regions[i].type = type;
d->io_regions[i].bus_flags = flags & IORESOURCE_BITS;
} else {
d->rom.base_addr = start;
d->rom.size = size;
d->rom.type = type;
d->rom.bus_flags = flags & IORESOURCE_BITS;
}
}
if (i != PCI_NUM_REGIONS) {
/* Invalid format or input to short */
rc = -ENODEV;
}
out:
close(fd);
return rc;
}
/* This size should be enough to read a long from a file */
#define XEN_HOST_PCI_GET_VALUE_BUFFER_SIZE 22
static int xen_host_pci_get_value(XenHostPCIDevice *d, const char *name,
unsigned int *pvalue, int base)
{
char path[PATH_MAX];
char buf[XEN_HOST_PCI_GET_VALUE_BUFFER_SIZE];
int fd, rc;
unsigned long value;
char *endptr;
rc = xen_host_pci_sysfs_path(d, name, path, sizeof (path));
if (rc) {
return rc;
}
fd = open(path, O_RDONLY);
if (fd == -1) {
XEN_HOST_PCI_LOG("Error: Can't open %s: %s\n", path, strerror(errno));
return -errno;
}
do {
rc = read(fd, &buf, sizeof (buf) - 1);
if (rc < 0 && errno != EINTR) {
rc = -errno;
goto out;
}
} while (rc < 0);
buf[rc] = 0;
value = strtol(buf, &endptr, base);
if (endptr == buf || *endptr != '\n') {
rc = -1;
} else if ((value == LONG_MIN || value == LONG_MAX) && errno == ERANGE) {
rc = -errno;
} else {
rc = 0;
*pvalue = value;
}
out:
close(fd);
return rc;
}
static inline int xen_host_pci_get_hex_value(XenHostPCIDevice *d,
const char *name,
unsigned int *pvalue)
{
return xen_host_pci_get_value(d, name, pvalue, 16);
}
static inline int xen_host_pci_get_dec_value(XenHostPCIDevice *d,
const char *name,
unsigned int *pvalue)
{
return xen_host_pci_get_value(d, name, pvalue, 10);
}
static bool xen_host_pci_dev_is_virtfn(XenHostPCIDevice *d)
{
char path[PATH_MAX];
struct stat buf;
if (xen_host_pci_sysfs_path(d, "physfn", path, sizeof (path))) {
return false;
}
return !stat(path, &buf);
}
static int xen_host_pci_config_open(XenHostPCIDevice *d)
{
char path[PATH_MAX];
int rc;
rc = xen_host_pci_sysfs_path(d, "config", path, sizeof (path));
if (rc) {
return rc;
}
d->config_fd = open(path, O_RDWR);
if (d->config_fd < 0) {
return -errno;
}
return 0;
}
static int xen_host_pci_config_read(XenHostPCIDevice *d,
int pos, void *buf, int len)
{
int rc;
do {
rc = pread(d->config_fd, buf, len, pos);
} while (rc < 0 && (errno == EINTR || errno == EAGAIN));
if (rc != len) {
return -errno;
}
return 0;
}
static int xen_host_pci_config_write(XenHostPCIDevice *d,
int pos, const void *buf, int len)
{
int rc;
do {
rc = pwrite(d->config_fd, buf, len, pos);
} while (rc < 0 && (errno == EINTR || errno == EAGAIN));
if (rc != len) {
return -errno;
}
return 0;
}
int xen_host_pci_get_byte(XenHostPCIDevice *d, int pos, uint8_t *p)
{
uint8_t buf;
int rc = xen_host_pci_config_read(d, pos, &buf, 1);
if (!rc) {
*p = buf;
}
return rc;
}
int xen_host_pci_get_word(XenHostPCIDevice *d, int pos, uint16_t *p)
{
uint16_t buf;
int rc = xen_host_pci_config_read(d, pos, &buf, 2);
if (!rc) {
*p = le16_to_cpu(buf);
}
return rc;
}
int xen_host_pci_get_long(XenHostPCIDevice *d, int pos, uint32_t *p)
{
uint32_t buf;
int rc = xen_host_pci_config_read(d, pos, &buf, 4);
if (!rc) {
*p = le32_to_cpu(buf);
}
return rc;
}
int xen_host_pci_get_block(XenHostPCIDevice *d, int pos, uint8_t *buf, int len)
{
return xen_host_pci_config_read(d, pos, buf, len);
}
int xen_host_pci_set_byte(XenHostPCIDevice *d, int pos, uint8_t data)
{
return xen_host_pci_config_write(d, pos, &data, 1);
}
int xen_host_pci_set_word(XenHostPCIDevice *d, int pos, uint16_t data)
{
data = cpu_to_le16(data);
return xen_host_pci_config_write(d, pos, &data, 2);
}
int xen_host_pci_set_long(XenHostPCIDevice *d, int pos, uint32_t data)
{
data = cpu_to_le32(data);
return xen_host_pci_config_write(d, pos, &data, 4);
}
int xen_host_pci_set_block(XenHostPCIDevice *d, int pos, uint8_t *buf, int len)
{
return xen_host_pci_config_write(d, pos, buf, len);
}
int xen_host_pci_find_ext_cap_offset(XenHostPCIDevice *d, uint32_t cap)
{
uint32_t header = 0;
int max_cap = XEN_HOST_PCI_MAX_EXT_CAP;
int pos = PCI_CONFIG_SPACE_SIZE;
do {
if (xen_host_pci_get_long(d, pos, &header)) {
break;
}
/*
* If we have no capabilities, this is indicated by cap ID,
* cap version and next pointer all being 0.
*/
if (header == 0) {
break;
}
if (PCI_EXT_CAP_ID(header) == cap) {
return pos;
}
pos = PCI_EXT_CAP_NEXT(header);
if (pos < PCI_CONFIG_SPACE_SIZE) {
break;
}
max_cap--;
} while (max_cap > 0);
return -1;
}
int xen_host_pci_device_get(XenHostPCIDevice *d, uint16_t domain,
uint8_t bus, uint8_t dev, uint8_t func)
{
unsigned int v;
int rc = 0;
d->config_fd = -1;
d->domain = domain;
d->bus = bus;
d->dev = dev;
d->func = func;
rc = xen_host_pci_config_open(d);
if (rc) {
goto error;
}
rc = xen_host_pci_get_resource(d);
if (rc) {
goto error;
}
rc = xen_host_pci_get_hex_value(d, "vendor", &v);
if (rc) {
goto error;
}
d->vendor_id = v;
rc = xen_host_pci_get_hex_value(d, "device", &v);
if (rc) {
goto error;
}
d->device_id = v;
rc = xen_host_pci_get_dec_value(d, "irq", &v);
if (rc) {
goto error;
}
d->irq = v;
rc = xen_host_pci_get_hex_value(d, "class", &v);
if (rc) {
goto error;
}
d->class_code = v;
d->is_virtfn = xen_host_pci_dev_is_virtfn(d);
return 0;
error:
if (d->config_fd >= 0) {
close(d->config_fd);
d->config_fd = -1;
}
return rc;
}
bool xen_host_pci_device_closed(XenHostPCIDevice *d)
{
return d->config_fd == -1;
}
void xen_host_pci_device_put(XenHostPCIDevice *d)
{
if (d->config_fd >= 0) {
close(d->config_fd);
d->config_fd = -1;
}
}