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-rw-r--r--grub-core/kern/i386/xen/pvh.c369
1 files changed, 369 insertions, 0 deletions
diff --git a/grub-core/kern/i386/xen/pvh.c b/grub-core/kern/i386/xen/pvh.c
new file mode 100644
index 0000000..91fbca8
--- /dev/null
+++ b/grub-core/kern/i386/xen/pvh.c
@@ -0,0 +1,369 @@
+/*
+ * GRUB -- GRand Unified Bootloader
+ * Copyright (C) 2018 Free Software Foundation, Inc.
+ *
+ * GRUB is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * GRUB is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GRUB. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <grub/kernel.h>
+#include <grub/misc.h>
+#include <grub/memory.h>
+#include <grub/mm.h>
+#include <grub/i386/cpuid.h>
+#include <grub/i386/io.h>
+#include <grub/xen.h>
+#include <xen/hvm/start_info.h>
+#include <grub/i386/linux.h>
+#include <grub/machine/kernel.h>
+#include <grub/machine/memory.h>
+#include <xen/hvm/params.h>
+#include <xen/memory.h>
+
+#define XEN_MEMORY_MAP_SIZE 128
+
+grub_uint64_t grub_rsdp_addr;
+
+static char hypercall_page[GRUB_XEN_PAGE_SIZE]
+ __attribute__ ((aligned (GRUB_XEN_PAGE_SIZE)));
+
+static grub_uint32_t xen_cpuid_base;
+static struct start_info grub_xen_start_page;
+static struct grub_e820_mmap_entry map[XEN_MEMORY_MAP_SIZE];
+static unsigned int nr_map_entries;
+
+static void
+grub_xen_cons_msg (const char *msg)
+{
+ const char *c;
+
+ for (c = msg; *c; c++)
+ grub_outb (*c, XEN_HVM_DEBUGCONS_IOPORT);
+}
+
+static void
+grub_xen_panic (const char *msg)
+{
+ grub_xen_cons_msg (msg);
+ grub_xen_cons_msg ("System halted!\n");
+
+ asm volatile ("cli");
+
+ while (1)
+ {
+ asm volatile ("hlt");
+ }
+}
+
+static void
+grub_xen_cpuid_base (void)
+{
+ grub_uint32_t base, eax, signature[3];
+
+ for (base = 0x40000000; base < 0x40010000; base += 0x100)
+ {
+ grub_cpuid (base, eax, signature[0], signature[1], signature[2]);
+ if (!grub_memcmp ("XenVMMXenVMM", signature, 12) && (eax - base) >= 2)
+ {
+ xen_cpuid_base = base;
+ return;
+ }
+ }
+
+ grub_xen_panic ("Found no Xen signature!\n");
+}
+
+static void
+grub_xen_setup_hypercall_page (void)
+{
+ grub_uint32_t msr, addr, eax, ebx, ecx, edx;
+
+ /* Get base address of Xen-specific MSRs. */
+ grub_cpuid (xen_cpuid_base + 2, eax, ebx, ecx, edx);
+ msr = ebx;
+ addr = (grub_uint32_t) (&hypercall_page);
+
+ /* Specify hypercall page address for Xen. */
+ asm volatile ("wrmsr" : : "c" (msr), "a" (addr), "d" (0) : "memory");
+}
+
+int
+grub_xen_hypercall (grub_uint32_t callno, grub_uint32_t a0,
+ grub_uint32_t a1, grub_uint32_t a2,
+ grub_uint32_t a3, grub_uint32_t a4,
+ grub_uint32_t a5 __attribute__ ((unused)))
+{
+ grub_uint32_t res;
+
+ asm volatile ("call *%[callno]"
+ : "=a" (res), "+b" (a0), "+c" (a1), "+d" (a2),
+ "+S" (a3), "+D" (a4)
+ : [callno] "a" (&hypercall_page[callno * 32])
+ : "memory");
+ return res;
+}
+
+static grub_uint32_t
+grub_xen_get_param (int idx)
+{
+ struct xen_hvm_param xhv;
+ int r;
+
+ xhv.domid = DOMID_SELF;
+ xhv.index = idx;
+ r = grub_xen_hypercall (__HYPERVISOR_hvm_op, HVMOP_get_param,
+ (grub_uint32_t) (&xhv), 0, 0, 0, 0);
+ if (r < 0)
+ grub_xen_panic ("Could not get parameter from Xen!\n");
+ return xhv.value;
+}
+
+static void *
+grub_xen_add_physmap (unsigned int space, void *addr)
+{
+ struct xen_add_to_physmap xatp;
+
+ xatp.domid = DOMID_SELF;
+ xatp.idx = 0;
+ xatp.space = space;
+ xatp.gpfn = (grub_addr_t) addr >> GRUB_XEN_LOG_PAGE_SIZE;
+ if (grub_xen_hypercall (__HYPERVISOR_memory_op, XENMEM_add_to_physmap,
+ (grub_uint32_t) (&xatp), 0, 0, 0, 0))
+ grub_xen_panic ("Memory_op hypercall failed!\n");
+ return addr;
+}
+
+static void
+grub_xen_sort_mmap (void)
+{
+ grub_uint64_t from, to;
+ unsigned int i;
+ struct grub_e820_mmap_entry tmp;
+
+ /* Align map entries to page boundaries. */
+ for (i = 0; i < nr_map_entries; i++)
+ {
+ from = map[i].addr;
+ to = from + map[i].len;
+ if (map[i].type == GRUB_MEMORY_AVAILABLE)
+ {
+ from = ALIGN_UP (from, GRUB_XEN_PAGE_SIZE);
+ to = ALIGN_DOWN (to, GRUB_XEN_PAGE_SIZE);
+ }
+ else
+ {
+ from = ALIGN_DOWN (from, GRUB_XEN_PAGE_SIZE);
+ to = ALIGN_UP (to, GRUB_XEN_PAGE_SIZE);
+ }
+ map[i].addr = from;
+ map[i].len = to - from;
+ }
+
+ again:
+ /* Sort entries by start address. */
+ for (i = 1; i < nr_map_entries; i++)
+ {
+ if (map[i].addr >= map[i - 1].addr)
+ continue;
+ tmp = map[i];
+ map[i] = map[i - 1];
+ map[i - 1] = tmp;
+ i = 0;
+ }
+
+ /* Detect overlapping areas. */
+ for (i = 1; i < nr_map_entries; i++)
+ {
+ if (map[i].addr >= map[i - 1].addr + map[i - 1].len)
+ continue;
+ tmp = map[i - 1];
+ map[i - 1].len = map[i].addr - map[i - 1].addr;
+ if (map[i].addr + map[i].len >= tmp.addr + tmp.len)
+ continue;
+ if (nr_map_entries < ARRAY_SIZE (map))
+ {
+ map[nr_map_entries].addr = map[i].addr + map[i].len;
+ map[nr_map_entries].len = tmp.addr + tmp.len - map[nr_map_entries].addr;
+ map[nr_map_entries].type = tmp.type;
+ nr_map_entries++;
+ goto again;
+ }
+ }
+
+ /* Merge adjacent entries. */
+ for (i = 1; i < nr_map_entries; i++)
+ {
+ if (map[i].type == map[i - 1].type &&
+ map[i].addr == map[i - 1].addr + map[i - 1].len)
+ {
+ map[i - 1].len += map[i].len;
+ map[i] = map[nr_map_entries - 1];
+ nr_map_entries--;
+ goto again;
+ }
+ }
+}
+
+static void
+grub_xen_get_mmap (void)
+{
+ struct xen_memory_map memmap;
+
+ memmap.nr_entries = ARRAY_SIZE (map);
+ set_xen_guest_handle (memmap.buffer, map);
+ if (grub_xen_hypercall (__HYPERVISOR_memory_op, XENMEM_memory_map,
+ (grub_uint32_t) (&memmap), 0, 0, 0, 0))
+ grub_xen_panic ("Could not get memory map from Xen!\n");
+ nr_map_entries = memmap.nr_entries;
+
+ grub_xen_sort_mmap ();
+}
+
+static void
+grub_xen_set_mmap (void)
+{
+ struct xen_foreign_memory_map memmap;
+
+ memmap.domid = DOMID_SELF;
+ memmap.map.nr_entries = nr_map_entries;
+ set_xen_guest_handle (memmap.map.buffer, map);
+ grub_xen_hypercall (__HYPERVISOR_memory_op, XENMEM_set_memory_map,
+ (grub_uint32_t) (&memmap), 0, 0, 0, 0);
+}
+
+static void
+grub_xen_mm_init_regions (void)
+{
+ grub_uint64_t modend, from, to;
+ unsigned int i;
+
+ modend = grub_modules_get_end ();
+
+ for (i = 0; i < nr_map_entries; i++)
+ {
+ if (map[i].type != GRUB_MEMORY_AVAILABLE)
+ continue;
+ from = map[i].addr;
+ to = from + map[i].len;
+ if (from < modend)
+ from = modend;
+ if (from >= to || from >= (1ULL << 32))
+ continue;
+ if (to > (1ULL << 32))
+ to = 1ULL << 32;
+ grub_mm_init_region ((void *) (grub_addr_t) from, to - from);
+ }
+}
+
+static grub_uint64_t
+grub_xen_find_page (grub_uint64_t start)
+{
+ unsigned int i, j;
+ grub_uint64_t last = start;
+
+ /*
+ * Try to find a e820 map hole below 4G.
+ * Relies on page-aligned entries (addr and len) and input (start).
+ */
+
+ for (i = 0; i < nr_map_entries; i++)
+ {
+ if (last > map[i].addr + map[i].len)
+ continue;
+ if (last < map[i].addr)
+ return last;
+ if ((map[i].addr >> 32) || ((map[i].addr + map[i].len) >> 32))
+ break;
+ last = map[i].addr + map[i].len;
+ }
+ if (i == nr_map_entries)
+ return last;
+
+ /* No hole found, use the highest RAM page below 4G and reserve it. */
+ if (nr_map_entries == ARRAY_SIZE (map))
+ grub_xen_panic ("Memory map size limit reached!\n");
+ for (i = 0, j = 0; i < nr_map_entries; i++)
+ {
+ if (map[i].type != GRUB_MEMORY_AVAILABLE)
+ continue;
+ if (map[i].addr >> 32)
+ break;
+ j = i;
+ if ((map[i].addr + map[i].len) >> 32)
+ break;
+ }
+ if (map[j].type != GRUB_MEMORY_AVAILABLE)
+ grub_xen_panic ("No free memory page found!\n");
+ if ((map[j].addr + map[j].len) >> 32)
+ last = (1ULL << 32) - GRUB_XEN_PAGE_SIZE;
+ else
+ last = map[j].addr + map[j].len - GRUB_XEN_PAGE_SIZE;
+ map[nr_map_entries].addr = last;
+ map[nr_map_entries].len = GRUB_XEN_PAGE_SIZE;
+ map[nr_map_entries].type = GRUB_MEMORY_RESERVED;
+ nr_map_entries++;
+ grub_xen_sort_mmap ();
+
+ return last;
+}
+
+void
+grub_xen_setup_pvh (void)
+{
+ grub_addr_t par;
+
+ grub_xen_cpuid_base ();
+ grub_xen_setup_hypercall_page ();
+ grub_xen_get_mmap ();
+
+ /* Setup Xen data. */
+ grub_xen_start_page_addr = &grub_xen_start_page;
+
+ par = grub_xen_get_param (HVM_PARAM_CONSOLE_PFN);
+ grub_xen_start_page_addr->console.domU.mfn = par;
+ grub_xen_xcons = (void *) (grub_addr_t) (par << GRUB_XEN_LOG_PAGE_SIZE);
+ par = grub_xen_get_param (HVM_PARAM_CONSOLE_EVTCHN);
+ grub_xen_start_page_addr->console.domU.evtchn = par;
+
+ par = grub_xen_get_param (HVM_PARAM_STORE_PFN);
+ grub_xen_start_page_addr->store_mfn = par;
+ grub_xen_xenstore = (void *) (grub_addr_t) (par << GRUB_XEN_LOG_PAGE_SIZE);
+ par = grub_xen_get_param (HVM_PARAM_STORE_EVTCHN);
+ grub_xen_start_page_addr->store_evtchn = par;
+
+ par = grub_xen_find_page (0);
+ grub_xen_grant_table = grub_xen_add_physmap (XENMAPSPACE_grant_table,
+ (void *) par);
+ par = grub_xen_find_page (par + GRUB_XEN_PAGE_SIZE);
+ grub_xen_shared_info = grub_xen_add_physmap (XENMAPSPACE_shared_info,
+ (void *) par);
+ grub_xen_set_mmap ();
+
+ grub_xen_mm_init_regions ();
+
+ grub_rsdp_addr = pvh_start_info->rsdp_paddr;
+}
+
+grub_err_t
+grub_machine_mmap_iterate (grub_memory_hook_t hook, void *hook_data)
+{
+ unsigned int i;
+
+ for (i = 0; i < nr_map_entries; i++)
+ {
+ if (map[i].len && hook (map[i].addr, map[i].len, map[i].type, hook_data))
+ break;
+ }
+
+ return GRUB_ERR_NONE;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-04 23:00:27 +0000