Hi,
On 09/11/16 00:39, Stefano Stabellini wrote:
On Wed, 28 Sep 2016, Andre Przywara wrote:
This introduces the ITS command handler for the CLEAR command, which
clears the pending state of an LPI.
This removes a not-yet injected, but already queued IRQ from a VCPU.
In addition this patch introduces the lookup function which translates
a given DeviceID/EventID pair into a pointer to our vITTE structure.
Signed-off-by: Andre Przywara <andre.przyw...@arm.com>
---
xen/arch/arm/vgic-its.c | 115 ++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 115 insertions(+)
diff --git a/xen/arch/arm/vgic-its.c b/xen/arch/arm/vgic-its.c
index 875b992..99d9e9c 100644
--- a/xen/arch/arm/vgic-its.c
+++ b/xen/arch/arm/vgic-its.c
@@ -61,6 +61,73 @@ struct vits_itte
uint64_t collection:16;
};
+#define UNMAPPED_COLLECTION ((uint16_t)~0)
+
+/* Must be called with the ITS lock held. */
+static struct vcpu *get_vcpu_from_collection(struct virt_its *its, int collid)
+{
+ uint16_t vcpu_id;
+
+ if ( collid >= its->max_collections )
+ return NULL;
+
+ vcpu_id = its->coll_table[collid];
+ if ( vcpu_id == UNMAPPED_COLLECTION || vcpu_id >= its->d->max_vcpus )
+ return NULL;
+
+ return its->d->vcpu[vcpu_id];
+}
+
+#define DEV_TABLE_ITT_ADDR(x) ((x) & GENMASK(51, 8))
+#define DEV_TABLE_ITT_SIZE(x) (BIT(((x) & GENMASK(7, 0)) + 1))
+#define DEV_TABLE_ENTRY(addr, bits) \
+ (((addr) & GENMASK(51, 8)) | (((bits) - 1) & GENMASK(7, 0)))
+
+static paddr_t get_itte_address(struct virt_its *its,
+ uint32_t devid, uint32_t evid)
+{
+ paddr_t addr;
+
+ if ( devid >= its->max_devices )
+ return ~0;
Please #define the error
Technically this should be INVALID_PADDR here.
+ if ( evid >= DEV_TABLE_ITT_SIZE(its->dev_table[devid]) )
+ return ~0;
same here
Ditto.
+ addr = DEV_TABLE_ITT_ADDR(its->dev_table[devid]);
+
+ return addr + evid * sizeof(struct vits_itte);
+}
+
+/* Looks up a given deviceID/eventID pair on an ITS and returns a pointer to
+ * the corresponding ITTE. This maps the respective guest page into Xen.
+ * Once finished with handling the ITTE, call put_devid_evid() to unmap
+ * the page again.
+ * Must be called with the ITS lock held.
+ */
+static struct vits_itte *get_devid_evid(struct virt_its *its,
+ uint32_t devid, uint32_t evid)
+{
+ paddr_t addr = get_itte_address(its, devid, evid);
+ struct vits_itte *itte;
+
+ if (addr == ~0)
+ return NULL;
+
+ /* TODO: check locking for map_guest_pages() */
+ itte = map_guest_pages(its->d, addr & PAGE_MASK, 1);
+ if ( !itte )
+ return NULL;
No need to use the vmap to map 1 page
But you do have to translate the IPA to a PA, so you cannot directly use
__pa on it.
+ return itte + (addr & ~PAGE_MASK) / sizeof(struct vits_itte);
Please use () around the div operation for clarity
+}
+
+/* Must be called with the ITS lock held. */
+static void put_devid_evid(struct virt_its *its, struct vits_itte *itte)
+{
+ unmap_guest_pages(itte, 1);
No need for this, once you use __pa instead of the vmap
Well, we should at least use map_domain_page/unmap_domain_page even if
they are a nop on ARM64. And not directly __pa.
Regards,
--
Julien Grall
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