Crash from Xen panic notifier, without executing late
panic() code such as dumping handler.
+ xen_msr_safe= [X86,XEN]
+ Format: <bool>
+ Select whether to always use non-faulting (safe) MSR
+ access functions when running as Xen PV guest. The
+ default value is controlled by CONFIG_XEN_PV_MSR_SAFE.
+
xen_nopvspin [X86,XEN]
Disables the qspinlock slowpath using Xen PV optimizations.
This parameter is obsoleted by "nopvspin" parameter, which
select X86_X2APIC if XEN_PVH && X86_64
help
Support running as a Xen Dom0 guest.
+
+config XEN_PV_MSR_SAFE
+ bool "Always use safe MSR accesses in PV guests"
+ default y
+ depends on XEN_PV
+ help
+ Use safe (not faulting) MSR access functions even if the MSR access
+ should not fault anyway.
+ The default can be changed by using the "xen_msr_safe" boot parameter.
return;
if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT))
- virtio_set_mem_acc_cb(virtio_require_restricted_mem_acc);
+ virtio_set_mem_acc_cb(xen_virtio_restricted_mem_acc);
init_hvm_pv_info();
*/
static DEFINE_PER_CPU(struct tls_descs, shadow_tls_desc);
+static __read_mostly bool xen_msr_safe = IS_ENABLED(CONFIG_XEN_PV_MSR_SAFE);
+
+static int __init parse_xen_msr_safe(char *str)
+{
+ if (str)
+ return strtobool(str, &xen_msr_safe);
+ return -EINVAL;
+}
+early_param("xen_msr_safe", parse_xen_msr_safe);
+
static void __init xen_pv_init_platform(void)
{
/* PV guests can't operate virtio devices without grants. */
if (IS_ENABLED(CONFIG_XEN_VIRTIO))
- virtio_set_mem_acc_cb(virtio_require_restricted_mem_acc);
+ virtio_set_mem_acc_cb(xen_virtio_restricted_mem_acc);
populate_extra_pte(fix_to_virt(FIX_PARAVIRT_BOOTMAP));
native_write_cr4(cr4);
}
-static u64 xen_read_msr_safe(unsigned int msr, int *err)
+static u64 xen_do_read_msr(unsigned int msr, int *err)
{
- u64 val;
+ u64 val = 0; /* Avoid uninitialized value for safe variant. */
if (pmu_msr_read(msr, &val, err))
return val;
- val = native_read_msr_safe(msr, err);
+ if (err)
+ val = native_read_msr_safe(msr, err);
+ else
+ val = native_read_msr(msr);
+
switch (msr) {
case MSR_IA32_APICBASE:
val &= ~X2APIC_ENABLE;
return val;
}
-static int xen_write_msr_safe(unsigned int msr, unsigned low, unsigned high)
+static void set_seg(unsigned int which, unsigned int low, unsigned int high,
+ int *err)
{
- int ret;
- unsigned int which;
- u64 base;
+ u64 base = ((u64)high << 32) | low;
- ret = 0;
+ if (HYPERVISOR_set_segment_base(which, base) == 0)
+ return;
+ if (err)
+ *err = -EIO;
+ else
+ WARN(1, "Xen set_segment_base(%u, %llx) failed\n", which, base);
+}
+
+/*
+ * Support write_msr_safe() and write_msr() semantics.
+ * With err == NULL write_msr() semantics are selected.
+ * Supplying an err pointer requires err to be pre-initialized with 0.
+ */
+static void xen_do_write_msr(unsigned int msr, unsigned int low,
+ unsigned int high, int *err)
+{
switch (msr) {
- case MSR_FS_BASE: which = SEGBASE_FS; goto set;
- case MSR_KERNEL_GS_BASE: which = SEGBASE_GS_USER; goto set;
- case MSR_GS_BASE: which = SEGBASE_GS_KERNEL; goto set;
-
- set:
- base = ((u64)high << 32) | low;
- if (HYPERVISOR_set_segment_base(which, base) != 0)
- ret = -EIO;
+ case MSR_FS_BASE:
+ set_seg(SEGBASE_FS, low, high, err);
+ break;
+
+ case MSR_KERNEL_GS_BASE:
+ set_seg(SEGBASE_GS_USER, low, high, err);
+ break;
+
+ case MSR_GS_BASE:
+ set_seg(SEGBASE_GS_KERNEL, low, high, err);
break;
case MSR_STAR:
break;
default:
- if (!pmu_msr_write(msr, low, high, &ret))
- ret = native_write_msr_safe(msr, low, high);
+ if (!pmu_msr_write(msr, low, high, err)) {
+ if (err)
+ *err = native_write_msr_safe(msr, low, high);
+ else
+ native_write_msr(msr, low, high);
+ }
}
+}
- return ret;
+static u64 xen_read_msr_safe(unsigned int msr, int *err)
+{
+ return xen_do_read_msr(msr, err);
+}
+
+static int xen_write_msr_safe(unsigned int msr, unsigned int low,
+ unsigned int high)
+{
+ int err = 0;
+
+ xen_do_write_msr(msr, low, high, &err);
+
+ return err;
}
static u64 xen_read_msr(unsigned int msr)
{
- /*
- * This will silently swallow a #GP from RDMSR. It may be worth
- * changing that.
- */
int err;
- return xen_read_msr_safe(msr, &err);
+ return xen_do_read_msr(msr, xen_msr_safe ? &err : NULL);
}
static void xen_write_msr(unsigned int msr, unsigned low, unsigned high)
{
- /*
- * This will silently swallow a #GP from WRMSR. It may be worth
- * changing that.
- */
- xen_write_msr_safe(msr, low, high);
+ int err;
+
+ xen_do_write_msr(msr, low, high, xen_msr_safe ? &err : NULL);
}
/* This is called once we have the cpu_possible_mask */
static inline bool is_amd_pmu_msr(unsigned int msr)
{
+ if (boot_cpu_data.x86_vendor != X86_VENDOR_AMD &&
+ boot_cpu_data.x86_vendor != X86_VENDOR_HYGON)
+ return false;
+
if ((msr >= MSR_F15H_PERF_CTL &&
msr < MSR_F15H_PERF_CTR + (amd_num_counters * 2)) ||
(msr >= MSR_K7_EVNTSEL0 &&
return false;
}
-static int is_intel_pmu_msr(u32 msr_index, int *type, int *index)
+static bool is_intel_pmu_msr(u32 msr_index, int *type, int *index)
{
u32 msr_index_pmc;
+ if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL &&
+ boot_cpu_data.x86_vendor != X86_VENDOR_CENTAUR &&
+ boot_cpu_data.x86_vendor != X86_VENDOR_ZHAOXIN)
+ return false;
+
switch (msr_index) {
case MSR_CORE_PERF_FIXED_CTR_CTRL:
case MSR_IA32_DS_AREA:
return false;
}
+static bool pmu_msr_chk_emulated(unsigned int msr, uint64_t *val, bool is_read,
+ bool *emul)
+{
+ int type, index;
+
+ if (is_amd_pmu_msr(msr))
+ *emul = xen_amd_pmu_emulate(msr, val, is_read);
+ else if (is_intel_pmu_msr(msr, &type, &index))
+ *emul = xen_intel_pmu_emulate(msr, val, type, index, is_read);
+ else
+ return false;
+
+ return true;
+}
+
bool pmu_msr_read(unsigned int msr, uint64_t *val, int *err)
{
- if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL) {
- if (is_amd_pmu_msr(msr)) {
- if (!xen_amd_pmu_emulate(msr, val, 1))
- *val = native_read_msr_safe(msr, err);
- return true;
- }
- } else {
- int type, index;
+ bool emulated;
- if (is_intel_pmu_msr(msr, &type, &index)) {
- if (!xen_intel_pmu_emulate(msr, val, type, index, 1))
- *val = native_read_msr_safe(msr, err);
- return true;
- }
+ if (!pmu_msr_chk_emulated(msr, val, true, &emulated))
+ return false;
+
+ if (!emulated) {
+ *val = err ? native_read_msr_safe(msr, err)
+ : native_read_msr(msr);
}
- return false;
+ return true;
}
bool pmu_msr_write(unsigned int msr, uint32_t low, uint32_t high, int *err)
{
uint64_t val = ((uint64_t)high << 32) | low;
+ bool emulated;
- if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL) {
- if (is_amd_pmu_msr(msr)) {
- if (!xen_amd_pmu_emulate(msr, &val, 0))
- *err = native_write_msr_safe(msr, low, high);
- return true;
- }
- } else {
- int type, index;
+ if (!pmu_msr_chk_emulated(msr, &val, false, &emulated))
+ return false;
- if (is_intel_pmu_msr(msr, &type, &index)) {
- if (!xen_intel_pmu_emulate(msr, &val, type, index, 0))
- *err = native_write_msr_safe(msr, low, high);
- return true;
- }
+ if (!emulated) {
+ if (err)
+ *err = native_write_msr_safe(msr, low, high);
+ else
+ native_write_msr(msr, low, high);
}
- return false;
+ return true;
}
static unsigned long long xen_amd_read_pmc(int counter)
int err;
struct pci_bus *b;
-#ifndef CONFIG_PCI_DOMAINS
- if (domain != 0) {
- dev_err(&pdev->xdev->dev,
- "PCI Root in non-zero PCI Domain! domain=%d\n", domain);
- dev_err(&pdev->xdev->dev,
- "Please compile with CONFIG_PCI_DOMAINS\n");
- return -EINVAL;
- }
-#endif
-
- dev_info(&pdev->xdev->dev, "Rescanning PCI Frontend Bus %04x:%02x\n",
- domain, bus);
-
b = pci_find_bus(domain, bus);
if (!b)
/* If the bus is unknown, create it. */
return pcifront_scan_root(pdev, domain, bus);
+ dev_info(&pdev->xdev->dev, "Rescanning PCI Frontend Bus %04x:%02x\n",
+ domain, bus);
+
err = pcifront_scan_bus(pdev, domain, bus, b);
/* Claim resources before going "live" with our devices */
return err;
}
-static int pcifront_try_connect(struct pcifront_device *pdev)
+static void pcifront_connect(struct pcifront_device *pdev)
{
- int err = -EFAULT;
+ int err;
int i, num_roots, len;
char str[64];
unsigned int domain, bus;
-
- /* Only connect once */
- if (xenbus_read_driver_state(pdev->xdev->nodename) !=
- XenbusStateInitialised)
- goto out;
-
- err = pcifront_connect_and_init_dma(pdev);
- if (err && err != -EEXIST) {
- xenbus_dev_fatal(pdev->xdev, err,
- "Error setting up PCI Frontend");
- goto out;
- }
-
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
"root_num", "%d", &num_roots);
if (err == -ENOENT) {
xenbus_dev_error(pdev->xdev, err,
"No PCI Roots found, trying 0000:00");
- err = pcifront_scan_root(pdev, 0, 0);
+ err = pcifront_rescan_root(pdev, 0, 0);
if (err) {
xenbus_dev_fatal(pdev->xdev, err,
"Error scanning PCI root 0000:00");
- goto out;
+ return;
}
num_roots = 0;
} else if (err != 1) {
- if (err == 0)
- err = -EINVAL;
- xenbus_dev_fatal(pdev->xdev, err,
+ xenbus_dev_fatal(pdev->xdev, err >= 0 ? -EINVAL : err,
"Error reading number of PCI roots");
- goto out;
+ return;
}
for (i = 0; i < num_roots; i++) {
len = snprintf(str, sizeof(str), "root-%d", i);
- if (unlikely(len >= (sizeof(str) - 1))) {
- err = -ENOMEM;
- goto out;
- }
+ if (unlikely(len >= (sizeof(str) - 1)))
+ return;
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
"%x:%x", &domain, &bus);
if (err != 2) {
- if (err >= 0)
- err = -EINVAL;
- xenbus_dev_fatal(pdev->xdev, err,
+ xenbus_dev_fatal(pdev->xdev, err >= 0 ? -EINVAL : err,
"Error reading PCI root %d", i);
- goto out;
+ return;
}
- err = pcifront_scan_root(pdev, domain, bus);
+ err = pcifront_rescan_root(pdev, domain, bus);
if (err) {
xenbus_dev_fatal(pdev->xdev, err,
"Error scanning PCI root %04x:%02x",
domain, bus);
- goto out;
+ return;
}
}
- err = xenbus_switch_state(pdev->xdev, XenbusStateConnected);
+ xenbus_switch_state(pdev->xdev, XenbusStateConnected);
+}
-out:
- return err;
+static void pcifront_try_connect(struct pcifront_device *pdev)
+{
+ int err;
+
+ /* Only connect once */
+ if (xenbus_read_driver_state(pdev->xdev->nodename) !=
+ XenbusStateInitialised)
+ return;
+
+ err = pcifront_connect_and_init_dma(pdev);
+ if (err && err != -EEXIST) {
+ xenbus_dev_fatal(pdev->xdev, err,
+ "Error setting up PCI Frontend");
+ return;
+ }
+
+ pcifront_connect(pdev);
}
static int pcifront_try_disconnect(struct pcifront_device *pdev)
return err;
}
-static int pcifront_attach_devices(struct pcifront_device *pdev)
+static void pcifront_attach_devices(struct pcifront_device *pdev)
{
- int err = -EFAULT;
- int i, num_roots, len;
- unsigned int domain, bus;
- char str[64];
-
- if (xenbus_read_driver_state(pdev->xdev->nodename) !=
+ if (xenbus_read_driver_state(pdev->xdev->nodename) ==
XenbusStateReconfiguring)
- goto out;
-
- err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend,
- "root_num", "%d", &num_roots);
- if (err == -ENOENT) {
- xenbus_dev_error(pdev->xdev, err,
- "No PCI Roots found, trying 0000:00");
- err = pcifront_rescan_root(pdev, 0, 0);
- if (err) {
- xenbus_dev_fatal(pdev->xdev, err,
- "Error scanning PCI root 0000:00");
- goto out;
- }
- num_roots = 0;
- } else if (err != 1) {
- if (err == 0)
- err = -EINVAL;
- xenbus_dev_fatal(pdev->xdev, err,
- "Error reading number of PCI roots");
- goto out;
- }
-
- for (i = 0; i < num_roots; i++) {
- len = snprintf(str, sizeof(str), "root-%d", i);
- if (unlikely(len >= (sizeof(str) - 1))) {
- err = -ENOMEM;
- goto out;
- }
-
- err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, str,
- "%x:%x", &domain, &bus);
- if (err != 2) {
- if (err >= 0)
- err = -EINVAL;
- xenbus_dev_fatal(pdev->xdev, err,
- "Error reading PCI root %d", i);
- goto out;
- }
-
- err = pcifront_rescan_root(pdev, domain, bus);
- if (err) {
- xenbus_dev_fatal(pdev->xdev, err,
- "Error scanning PCI root %04x:%02x",
- domain, bus);
- goto out;
- }
- }
-
- xenbus_switch_state(pdev->xdev, XenbusStateConnected);
-
-out:
- return err;
+ pcifront_connect(pdev);
}
static int pcifront_detach_devices(struct pcifront_device *pdev)
{
int err = 0;
int i, num_devs;
+ enum xenbus_state state;
unsigned int domain, bus, slot, func;
struct pci_dev *pci_dev;
char str[64];
- if (xenbus_read_driver_state(pdev->xdev->nodename) !=
- XenbusStateConnected)
+ state = xenbus_read_driver_state(pdev->xdev->nodename);
+ if (state == XenbusStateInitialised) {
+ dev_dbg(&pdev->xdev->dev, "Handle skipped connect.\n");
+ /* We missed Connected and need to initialize. */
+ err = pcifront_connect_and_init_dma(pdev);
+ if (err && err != -EEXIST) {
+ xenbus_dev_fatal(pdev->xdev, err,
+ "Error setting up PCI Frontend");
+ goto out;
+ }
+
+ goto out_switch_state;
+ } else if (state != XenbusStateConnected) {
goto out;
+ }
err = xenbus_scanf(XBT_NIL, pdev->xdev->otherend, "num_devs", "%d",
&num_devs);
domain, bus, slot, func);
}
+ out_switch_state:
err = xenbus_switch_state(pdev->xdev, XenbusStateReconfiguring);
out:
depends on XEN_HAVE_PVMMU
depends on MEMORY_HOTPLUG
help
- Maxmium amount of memory (in GiB) that a PV guest can be
+ Maximum amount of memory (in GiB) that a PV guest can be
expanded to when using memory hotplug.
A PV guest can have more memory than this limit if is
};
struct gntdev_grant_map {
+ atomic_t in_use;
struct mmu_interval_notifier notifier;
+ bool notifier_init;
struct list_head next;
- struct vm_area_struct *vma;
int index;
int count;
int flags;
*/
}
+ if (use_ptemod && map->notifier_init)
+ mmu_interval_notifier_remove(&map->notifier);
+
if (map->notify.flags & UNMAP_NOTIFY_SEND_EVENT) {
notify_remote_via_evtchn(map->notify.event);
evtchn_put(map->notify.event);
static int find_grant_ptes(pte_t *pte, unsigned long addr, void *data)
{
struct gntdev_grant_map *map = data;
- unsigned int pgnr = (addr - map->vma->vm_start) >> PAGE_SHIFT;
+ unsigned int pgnr = (addr - map->pages_vm_start) >> PAGE_SHIFT;
int flags = map->flags | GNTMAP_application_map | GNTMAP_contains_pte |
(1 << _GNTMAP_guest_avail0);
u64 pte_maddr;
for (i = 0; i < map->count; i++) {
if (map->map_ops[i].status == GNTST_okay) {
map->unmap_ops[i].handle = map->map_ops[i].handle;
- if (!use_ptemod)
- alloced++;
+ alloced++;
} else if (!err)
err = -EINVAL;
if (use_ptemod) {
if (map->kmap_ops[i].status == GNTST_okay) {
- if (map->map_ops[i].status == GNTST_okay)
- alloced++;
+ alloced++;
map->kunmap_ops[i].handle = map->kmap_ops[i].handle;
} else if (!err)
err = -EINVAL;
unsigned int i;
struct gntdev_grant_map *map = data->data;
unsigned int offset = data->unmap_ops - map->unmap_ops;
+ int successful_unmaps = 0;
+ int live_grants;
for (i = 0; i < data->count; i++) {
+ if (map->unmap_ops[offset + i].status == GNTST_okay &&
+ map->unmap_ops[offset + i].handle != INVALID_GRANT_HANDLE)
+ successful_unmaps++;
+
WARN_ON(map->unmap_ops[offset + i].status != GNTST_okay &&
map->unmap_ops[offset + i].handle != INVALID_GRANT_HANDLE);
pr_debug("unmap handle=%d st=%d\n",
map->unmap_ops[offset+i].status);
map->unmap_ops[offset+i].handle = INVALID_GRANT_HANDLE;
if (use_ptemod) {
+ if (map->kunmap_ops[offset + i].status == GNTST_okay &&
+ map->kunmap_ops[offset + i].handle != INVALID_GRANT_HANDLE)
+ successful_unmaps++;
+
WARN_ON(map->kunmap_ops[offset + i].status != GNTST_okay &&
map->kunmap_ops[offset + i].handle != INVALID_GRANT_HANDLE);
pr_debug("kunmap handle=%u st=%d\n",
map->kunmap_ops[offset+i].handle = INVALID_GRANT_HANDLE;
}
}
+
/*
* Decrease the live-grant counter. This must happen after the loop to
* prevent premature reuse of the grants by gnttab_mmap().
*/
- atomic_sub(data->count, &map->live_grants);
+ live_grants = atomic_sub_return(successful_unmaps, &map->live_grants);
+ if (WARN_ON(live_grants < 0))
+ pr_err("%s: live_grants became negative (%d) after unmapping %d pages!\n",
+ __func__, live_grants, successful_unmaps);
/* Release reference taken by __unmap_grant_pages */
gntdev_put_map(NULL, map);
struct gntdev_priv *priv = file->private_data;
pr_debug("gntdev_vma_close %p\n", vma);
- if (use_ptemod) {
- WARN_ON(map->vma != vma);
- mmu_interval_notifier_remove(&map->notifier);
- map->vma = NULL;
- }
+
vma->vm_private_data = NULL;
gntdev_put_map(priv, map);
}
struct gntdev_grant_map *map =
container_of(mn, struct gntdev_grant_map, notifier);
unsigned long mstart, mend;
+ unsigned long map_start, map_end;
if (!mmu_notifier_range_blockable(range))
return false;
+ map_start = map->pages_vm_start;
+ map_end = map->pages_vm_start + (map->count << PAGE_SHIFT);
+
/*
* If the VMA is split or otherwise changed the notifier is not
* updated, but we don't want to process VA's outside the modified
* VMA. FIXME: It would be much more understandable to just prevent
* modifying the VMA in the first place.
*/
- if (map->vma->vm_start >= range->end ||
- map->vma->vm_end <= range->start)
+ if (map_start >= range->end || map_end <= range->start)
return true;
- mstart = max(range->start, map->vma->vm_start);
- mend = min(range->end, map->vma->vm_end);
+ mstart = max(range->start, map_start);
+ mend = min(range->end, map_end);
pr_debug("map %d+%d (%lx %lx), range %lx %lx, mrange %lx %lx\n",
- map->index, map->count,
- map->vma->vm_start, map->vma->vm_end,
- range->start, range->end, mstart, mend);
- unmap_grant_pages(map,
- (mstart - map->vma->vm_start) >> PAGE_SHIFT,
- (mend - mstart) >> PAGE_SHIFT);
+ map->index, map->count, map_start, map_end,
+ range->start, range->end, mstart, mend);
+ unmap_grant_pages(map, (mstart - map_start) >> PAGE_SHIFT,
+ (mend - mstart) >> PAGE_SHIFT);
return true;
}
return -EINVAL;
pr_debug("map %d+%d at %lx (pgoff %lx)\n",
- index, count, vma->vm_start, vma->vm_pgoff);
+ index, count, vma->vm_start, vma->vm_pgoff);
mutex_lock(&priv->lock);
map = gntdev_find_map_index(priv, index, count);
if (!map)
goto unlock_out;
- if (use_ptemod && map->vma)
+ if (!atomic_add_unless(&map->in_use, 1, 1))
goto unlock_out;
- if (atomic_read(&map->live_grants)) {
- err = -EAGAIN;
- goto unlock_out;
- }
+
refcount_inc(&map->users);
vma->vm_ops = &gntdev_vmops;
map->flags |= GNTMAP_readonly;
}
+ map->pages_vm_start = vma->vm_start;
+
if (use_ptemod) {
- map->vma = vma;
err = mmu_interval_notifier_insert_locked(
&map->notifier, vma->vm_mm, vma->vm_start,
vma->vm_end - vma->vm_start, &gntdev_mmu_ops);
- if (err) {
- map->vma = NULL;
+ if (err)
goto out_unlock_put;
- }
+
+ map->notifier_init = true;
}
mutex_unlock(&priv->lock);
*/
mmu_interval_read_begin(&map->notifier);
- map->pages_vm_start = vma->vm_start;
err = apply_to_page_range(vma->vm_mm, vma->vm_start,
vma->vm_end - vma->vm_start,
find_grant_ptes, map);
out_unlock_put:
mutex_unlock(&priv->lock);
out_put_map:
- if (use_ptemod) {
+ if (use_ptemod)
unmap_grant_pages(map, 0, map->count);
- if (map->vma) {
- mmu_interval_notifier_remove(&map->notifier);
- map->vma = NULL;
- }
- }
gntdev_put_map(priv, map);
return err;
}
bool broken;
};
-static DEFINE_XARRAY(xen_grant_dma_devices);
+static DEFINE_XARRAY_FLAGS(xen_grant_dma_devices, XA_FLAGS_LOCK_IRQ);
#define XEN_GRANT_DMA_ADDR_OFF (1ULL << 63)
static struct xen_grant_dma_data *find_xen_grant_dma_data(struct device *dev)
{
struct xen_grant_dma_data *data;
+ unsigned long flags;
- xa_lock(&xen_grant_dma_devices);
+ xa_lock_irqsave(&xen_grant_dma_devices, flags);
data = xa_load(&xen_grant_dma_devices, (unsigned long)dev);
- xa_unlock(&xen_grant_dma_devices);
+ xa_unlock_irqrestore(&xen_grant_dma_devices, flags);
return data;
}
+static int store_xen_grant_dma_data(struct device *dev,
+ struct xen_grant_dma_data *data)
+{
+ unsigned long flags;
+ int ret;
+
+ xa_lock_irqsave(&xen_grant_dma_devices, flags);
+ ret = xa_err(__xa_store(&xen_grant_dma_devices, (unsigned long)dev, data,
+ GFP_ATOMIC));
+ xa_unlock_irqrestore(&xen_grant_dma_devices, flags);
+
+ return ret;
+}
+
/*
* DMA ops for Xen frontends (e.g. virtio).
*
unsigned long attrs)
{
struct xen_grant_dma_data *data;
- unsigned int i, n_pages = PFN_UP(size);
+ unsigned int i, n_pages = PFN_UP(offset + size);
grant_ref_t grant;
dma_addr_t dma_handle;
unsigned long attrs)
{
struct xen_grant_dma_data *data;
- unsigned int i, n_pages = PFN_UP(size);
+ unsigned long offset = dma_handle & (PAGE_SIZE - 1);
+ unsigned int i, n_pages = PFN_UP(offset + size);
grant_ref_t grant;
if (WARN_ON(dir == DMA_NONE))
.dma_supported = xen_grant_dma_supported,
};
-bool xen_is_grant_dma_device(struct device *dev)
+static bool xen_is_dt_grant_dma_device(struct device *dev)
{
struct device_node *iommu_np;
bool has_iommu;
- /* XXX Handle only DT devices for now */
- if (!dev->of_node)
- return false;
-
iommu_np = of_parse_phandle(dev->of_node, "iommus", 0);
- has_iommu = iommu_np && of_device_is_compatible(iommu_np, "xen,grant-dma");
+ has_iommu = iommu_np &&
+ of_device_is_compatible(iommu_np, "xen,grant-dma");
of_node_put(iommu_np);
return has_iommu;
}
+bool xen_is_grant_dma_device(struct device *dev)
+{
+ /* XXX Handle only DT devices for now */
+ if (dev->of_node)
+ return xen_is_dt_grant_dma_device(dev);
+
+ return false;
+}
+
bool xen_virtio_mem_acc(struct virtio_device *dev)
{
- if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT))
+ if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT) || xen_pv_domain())
return true;
return xen_is_grant_dma_device(dev->dev.parent);
}
-void xen_grant_setup_dma_ops(struct device *dev)
+static int xen_dt_grant_init_backend_domid(struct device *dev,
+ struct xen_grant_dma_data *data)
{
- struct xen_grant_dma_data *data;
struct of_phandle_args iommu_spec;
- data = find_xen_grant_dma_data(dev);
- if (data) {
- dev_err(dev, "Xen grant DMA data is already created\n");
- return;
- }
-
- /* XXX ACPI device unsupported for now */
- if (!dev->of_node)
- goto err;
-
if (of_parse_phandle_with_args(dev->of_node, "iommus", "#iommu-cells",
0, &iommu_spec)) {
dev_err(dev, "Cannot parse iommus property\n");
- goto err;
+ return -ESRCH;
}
if (!of_device_is_compatible(iommu_spec.np, "xen,grant-dma") ||
iommu_spec.args_count != 1) {
dev_err(dev, "Incompatible IOMMU node\n");
of_node_put(iommu_spec.np);
- goto err;
+ return -ESRCH;
}
of_node_put(iommu_spec.np);
+ /*
+ * The endpoint ID here means the ID of the domain where the
+ * corresponding backend is running
+ */
+ data->backend_domid = iommu_spec.args[0];
+
+ return 0;
+}
+
+void xen_grant_setup_dma_ops(struct device *dev)
+{
+ struct xen_grant_dma_data *data;
+
+ data = find_xen_grant_dma_data(dev);
+ if (data) {
+ dev_err(dev, "Xen grant DMA data is already created\n");
+ return;
+ }
+
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
goto err;
- /*
- * The endpoint ID here means the ID of the domain where the corresponding
- * backend is running
- */
- data->backend_domid = iommu_spec.args[0];
+ if (dev->of_node) {
+ if (xen_dt_grant_init_backend_domid(dev, data))
+ goto err;
+ } else if (IS_ENABLED(CONFIG_XEN_VIRTIO_FORCE_GRANT)) {
+ dev_info(dev, "Using dom0 as backend\n");
+ data->backend_domid = 0;
+ } else {
+ /* XXX ACPI device unsupported for now */
+ goto err;
+ }
- if (xa_err(xa_store(&xen_grant_dma_devices, (unsigned long)dev, data,
- GFP_KERNEL))) {
+ if (store_xen_grant_dma_data(dev, data)) {
dev_err(dev, "Cannot store Xen grant DMA data\n");
goto err;
}
return;
err:
+ devm_kfree(dev, data);
dev_err(dev, "Cannot set up Xen grant DMA ops, retain platform DMA ops\n");
}
+bool xen_virtio_restricted_mem_acc(struct virtio_device *dev)
+{
+ bool ret = xen_virtio_mem_acc(dev);
+
+ if (ret)
+ xen_grant_setup_dma_ops(dev->dev.parent);
+
+ return ret;
+}
+
MODULE_DESCRIPTION("Xen grant DMA-mapping layer");
MODULE_AUTHOR("Juergen Gross <jgross@suse.com>");
MODULE_LICENSE("GPL");
" frontend (for example, a device at 06:01.b will still appear at\n"\
" 06:01.b to the frontend). This is similar to how Xen 2.0.x\n"\
" exposed PCI devices to its driver domains. This may be required\n"\
- " for drivers which depend on finding their hardward in certain\n"\
+ " for drivers which depend on finding their hardware in certain\n"\
" bus/slot locations.");
static struct xen_pcibk_device *alloc_pdev(struct xenbus_device *xdev)
void xen_grant_setup_dma_ops(struct device *dev);
bool xen_is_grant_dma_device(struct device *dev);
bool xen_virtio_mem_acc(struct virtio_device *dev);
+bool xen_virtio_restricted_mem_acc(struct virtio_device *dev);
#else
static inline void xen_grant_setup_dma_ops(struct device *dev)
{
{
return false;
}
+
+static inline bool xen_virtio_restricted_mem_acc(struct virtio_device *dev)
+{
+ return false;
+}
#endif /* CONFIG_XEN_GRANT_DMA_OPS */
#endif /* INCLUDE_XEN_OPS_H */
projects / platform / kernel / linux-starfive.git / commitdiff