support T13 EDD3.0 spec

Some guests (such as Linux) expect BIOS to behave according to T13
EDD3.0 spec. T13 spec is much better then Phoenix since it provides
more information about interface and device paths. This patch adds
support for the spec. If guest provides buffer with enough space for
T13 EDD info return EDD according to T13 spec otherwise use Phoenix
one.

Signed-off-by: Gleb Natapov <gleb@redhat.com>

diff --git a/src/disk.c b/src/disk.c
index f7bfe9c523ef16104c65c1fc4a5902e25778c3c7..8f7c61ff0f486b35745953681565883a9d635f1f 100644 (file)
--- a/src/disk.c
+++ b/src/disk.c
@@ -503,6 +503,7 @@ static void
 disk_1348(struct bregs *regs, struct drive_s *drive_g)
 {
     u16 size = GET_INT13DPT(regs, size);
+    u16 t13 = size == 74;
 
     // Buffer is too small
     if (size < 26) {
@@ -553,8 +554,9 @@ disk_1348(struct bregs *regs, struct drive_s *drive_g)
     // EDD 2.x
 
     int bdf;
-    u16 iobase1;
-    u64 device_path;
+    u16 iobase1 = 0;
+    u64 device_path = 0;
+    u8 channel = 0;
     SET_INT13DPT(regs, size, 30);
     if (type == DTYPE_ATA || type == DTYPE_ATAPI) {
         u16 ebda_seg = get_ebda_seg();
@@ -573,6 +575,7 @@ disk_1348(struct bregs *regs, struct drive_s *drive_g)
         iobase1 = GET_GLOBALFLAT(chan_gf->iobase1);
         bdf = GET_GLOBALFLAT(chan_gf->pci_bdf);
         device_path = slave;
+        channel = GET_GLOBALFLAT(chan_gf->chanid);
 
         u16 options = 0;
         if (type == DTYPE_ATA) {
@@ -613,8 +616,6 @@ disk_1348(struct bregs *regs, struct drive_s *drive_g)
         SET_INT13DPT(regs, dpte_segment, 0);
         SET_INT13DPT(regs, dpte_offset, 0);
         bdf = GET_GLOBAL(drive_g->cntl_id);
-        device_path = 0;
-        iobase1 = 0;
     }
 
     if (size < 66) {
@@ -624,7 +625,7 @@ disk_1348(struct bregs *regs, struct drive_s *drive_g)
 
     // EDD 3.x
     SET_INT13DPT(regs, key, 0xbedd);
-    SET_INT13DPT(regs, dpi_length, 36);
+    SET_INT13DPT(regs, dpi_length, t13 ? 44 : 36);
     SET_INT13DPT(regs, reserved1, 0);
     SET_INT13DPT(regs, reserved2, 0);
 
@@ -632,17 +633,20 @@ disk_1348(struct bregs *regs, struct drive_s *drive_g)
         SET_INT13DPT(regs, host_bus[0], 'P');
         SET_INT13DPT(regs, host_bus[1], 'C');
         SET_INT13DPT(regs, host_bus[2], 'I');
-        SET_INT13DPT(regs, host_bus[3], 0);
+        SET_INT13DPT(regs, host_bus[3], ' ');
 
         u32 path = (pci_bdf_to_bus(bdf) | (pci_bdf_to_dev(bdf) << 8)
                     | (pci_bdf_to_fn(bdf) << 16));
+        if (t13)
+            path |= channel << 24;
+
         SET_INT13DPT(regs, iface_path, path);
     } else {
         // ISA
         SET_INT13DPT(regs, host_bus[0], 'I');
         SET_INT13DPT(regs, host_bus[1], 'S');
         SET_INT13DPT(regs, host_bus[2], 'A');
-        SET_INT13DPT(regs, host_bus[3], 0);
+        SET_INT13DPT(regs, host_bus[3], ' ');
 
         SET_INT13DPT(regs, iface_path, iobase1);
     }
@@ -651,22 +655,30 @@ disk_1348(struct bregs *regs, struct drive_s *drive_g)
         SET_INT13DPT(regs, iface_type[0], 'A');
         SET_INT13DPT(regs, iface_type[1], 'T');
         SET_INT13DPT(regs, iface_type[2], 'A');
-        SET_INT13DPT(regs, iface_type[3], 0);
+        SET_INT13DPT(regs, iface_type[3], ' ');
     } else {
         SET_INT13DPT(regs, iface_type[0], 'S');
         SET_INT13DPT(regs, iface_type[1], 'C');
         SET_INT13DPT(regs, iface_type[2], 'S');
         SET_INT13DPT(regs, iface_type[3], 'I');
     }
-    SET_INT13DPT(regs, iface_type[4], 0);
-    SET_INT13DPT(regs, iface_type[5], 0);
-    SET_INT13DPT(regs, iface_type[6], 0);
-    SET_INT13DPT(regs, iface_type[7], 0);
+    SET_INT13DPT(regs, iface_type[4], ' ');
+    SET_INT13DPT(regs, iface_type[5], ' ');
+    SET_INT13DPT(regs, iface_type[6], ' ');
+    SET_INT13DPT(regs, iface_type[7], ' ');
+
+    if (t13) {
+        SET_INT13DPT(regs, t13.device_path[0], device_path);
+        SET_INT13DPT(regs, t13.device_path[1], 0);
 
-    SET_INT13DPT(regs, device_path, device_path);
+        SET_INT13DPT(regs, t13.checksum
+                     , -checksum_far(regs->ds, (void*)(regs->si+30), 43));
+    } else {
+        SET_INT13DPT(regs, phoenix.device_path, device_path);
 
-    SET_INT13DPT(regs, checksum
-                 , -checksum_far(regs->ds, (void*)(regs->si+30), 35));
+        SET_INT13DPT(regs, phoenix.checksum
+                     , -checksum_far(regs->ds, (void*)(regs->si+30), 35));
+    }
 
     disk_ret(regs, DISK_RET_SUCCESS);
 }

diff --git a/src/disk.h b/src/disk.h
index f31de73ac5bec09e1fef5a28b58b9622c1516c7e..10a00511fa5bce0a48b3e05a9936e2fddcd44465 100644 (file)
--- a/src/disk.h
+++ b/src/disk.h
@@ -63,9 +63,18 @@ struct int13dpt_s {
     u8  host_bus[4];
     u8  iface_type[8];
     u64 iface_path;
-    u64 device_path;
-    u8  reserved3;
-    u8  checksum;
+    union {
+        struct {
+            u64 device_path;
+            u8  reserved3;
+            u8  checksum;
+        } phoenix;
+        struct {
+            u64 device_path[2];
+            u8  reserved3;
+            u8  checksum;
+        } t13;
+    };
 } PACKED;
 
 #define GET_INT13DPT(regs,var)                                          \