This patch flushes the device table entries into guest RAM.
Both flat table and 2 stage tables are supported. DeviceId
indexing is used.
For each device listed in the device table, we also flush
the translation table using the vgic_its_flush/restore_itt
routines.
On restore, devices are re-allocated and their itte are
re-built.
Signed-off-by: Eric Auger <eric.auger@xxxxxxxxxx>
---
v2 -> v3:
- fix itt_addr bitmask in vgic_its_restore_dte
- addition of return 0 in vgic_its_restore_ite moved to
the ITE related patch
v1 -> v2:
- use 8 byte format for DTE and ITE
- support 2 stage format
- remove kvm parameter
- ITT flush/restore moved in a separate patch
- use deviceid indexing
---
virt/kvm/arm/vgic/vgic-its.c | 144 ++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 142 insertions(+), 2 deletions(-)
diff --git a/virt/kvm/arm/vgic/vgic-its.c b/virt/kvm/arm/vgic/vgic-its.c
index a216849..27ebabd 100644
--- a/virt/kvm/arm/vgic/vgic-its.c
+++ b/virt/kvm/arm/vgic/vgic-its.c
@@ -1849,12 +1849,137 @@ static int vgic_its_restore_itt(struct vgic_its *its,
}
/**
+ * vgic_its_flush_dte - Flush a device table entry at a given GPA
+ *
+ * @its: ITS handle
+ * @dev: ITS device
+ * @ptr: GPA
+ */
+static int vgic_its_flush_dte(struct vgic_its *its,
+ struct its_device *dev, gpa_t ptr)
+{
+ struct kvm *kvm = its->dev->kvm;
+ u64 val, itt_addr_field;
+ int ret;
+ u32 next_offset;
+
+ itt_addr_field = dev->itt_addr >> 8;
+ next_offset = compute_next_devid_offset(&its->device_list, dev);
+ val = (((u64)next_offset << 45) | (itt_addr_field << 5) |
+ (dev->nb_eventid_bits - 1));
+ val = cpu_to_le64(val);
+ ret = kvm_write_guest(kvm, ptr, &val, 8);
+ return ret;
+}
+
+/**
+ * vgic_its_restore_dte - restore a device table entry
+ *
+ * @its: its handle
+ * @id: device id the DTE corresponds to
+ * @ptr: kernel VA where the 8 byte DTE is located
+ * @opaque: unused
+ * @next: offset to the next valid device id
+ *
+ * Return: < 0 on error, 0 otherwise
+ */
+static int vgic_its_restore_dte(struct vgic_its *its, u32 id,
+ void *ptr, void *opaque, u32 *next)
+{
+ struct its_device *dev;
+ gpa_t itt_addr;
+ size_t size;
+ u64 val, *p = (u64 *)ptr;
+ int ret;
+
+ val = *p;
+ val = le64_to_cpu(val);
+
+ size = val & GENMASK_ULL(4, 0);
+ itt_addr = (val & GENMASK_ULL(44, 5)) >> 5;
+ *next = 1;
+
+ if (!itt_addr)
+ return 0;
+
+ /* dte entry is valid */
+ *next = (val & GENMASK_ULL(63, 45)) >> 45;
+
+ ret = vgic_its_alloc_device(its, &dev, id,
+ itt_addr, size);
+ if (ret)
+ return ret;
+ ret = vgic_its_restore_itt(its, dev);
+
+ return ret;
+}
+
+/**
* vgic_its_flush_device_tables - flush the device table and all ITT
* into guest RAM
*/
static int vgic_its_flush_device_tables(struct vgic_its *its)
{
- return -ENXIO;
+ struct its_device *dev;
+ u64 baser;
+
+ baser = its->baser_device_table;
+
+ list_for_each_entry(dev, &its->device_list, dev_list) {
+ int ret;
+ gpa_t eaddr;
+
+ if (!vgic_its_check_id(its, baser,
+ dev->device_id, &eaddr))
+ return -EINVAL;
+
+ ret = vgic_its_flush_itt(its, dev);
+ if (ret)
+ return ret;
+
+ ret = vgic_its_flush_dte(its, dev, eaddr);
+ if (ret)
+ return ret;
+ }
+ return 0;
+}
+
+/**
+ * handle_l1_entry - callback used for L1 entries (2 stage case)
+ *
+ * @its: its handle
+ * @id: id
+ * @addr: kernel VA
+ * @opaque: unused
+ * @next_offset: offset to the next L1 entry: 0 if the last element
+ * was found, 1 otherwise
+ */
+static int handle_l1_entry(struct vgic_its *its, u32 id, void *addr,
+ void *opaque, u32 *next_offset)
+{
+ u64 *pe = addr;
+ gpa_t gpa;
+ int l2_start_id = id * (SZ_64K / 8);
+ int ret;
+
+ *pe = le64_to_cpu(*pe);
+ *next_offset = 1;
+
+ if (!(*pe & BIT_ULL(63)))
+ return 0;
+
+ gpa = *pe & GENMASK_ULL(51, 16);
+
+ ret = lookup_table(its, gpa, SZ_64K, 8,
+ l2_start_id, vgic_its_restore_dte, NULL);
+
+ if (ret == 1) {
+ /* last entry was found in this L2 table */
+ *next_offset = 0;
+ ret = 0;
+ }
+
+ return ret;
}
/**
@@ -1863,7 +1988,22 @@ static int vgic_its_flush_device_tables(struct vgic_its *its)
*/
static int vgic_its_restore_device_tables(struct vgic_its *its)
{
- return -ENXIO;
+ u64 baser = its->baser_device_table;
+ int l1_tbl_size = GITS_BASER_NR_PAGES(baser) * SZ_64K;
+ int l1_esz = GITS_BASER_ENTRY_SIZE(baser);
+ gpa_t l1_gpa;
+
+ l1_gpa = BASER_ADDRESS(baser);
+ if (!l1_gpa)
+ return 0;
+
+ if (!(baser & GITS_BASER_INDIRECT))
+ return lookup_table(its, l1_gpa, l1_tbl_size, l1_esz,
+ 0, vgic_its_restore_dte, NULL);
+
+ /* two stage table */
+ return lookup_table(its, l1_gpa, l1_tbl_size, 8, 0,
+ handle_l1_entry, NULL);
}
static int vgic_its_flush_cte(struct vgic_its *its,
--
2.5.5
