arm: compile libxenguest

Introduce an empty implementation of the arch specific ARM functions in
xc_dom_arm.c.
Provide empty implementations of xc_domain_save and xc_domain_restore
when CONFIG_MIGRATE is not set.
Move xc_hvm_build.c to xc_hvm_build_x86.c because the implementation is
x86 specific, introduce xc_hvm_build_arm.c with empty stubs.

Signed-off-by: Stefano Stabellini <stefano.stabellini@eu.citrix.com>
Acked-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>
Committed-by: Ian Campbell <ian.campbell@citrix.com>

1 files changed, 472 insertions, 0 deletions

diff --git a/tools/libxc/xc_hvm_build_x86.c b/tools/libxc/xc_hvm_build_x86.c
new file mode 100644
index 0000000000..696c012291
--- /dev/null
+++ b/tools/libxc/xc_hvm_build_x86.c
@@ -0,0 +1,472 @@
+/******************************************************************************
+ * xc_hvm_build.c
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+#include <stddef.h>
+#include <inttypes.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <zlib.h>
+
+#include "xg_private.h"
+#include "xc_private.h"
+
+#include <xen/foreign/x86_32.h>
+#include <xen/foreign/x86_64.h>
+#include <xen/hvm/hvm_info_table.h>
+#include <xen/hvm/params.h>
+#include <xen/hvm/e820.h>
+
+#include <xen/libelf/libelf.h>
+
+#define SUPERPAGE_2MB_SHIFT   9
+#define SUPERPAGE_2MB_NR_PFNS (1UL << SUPERPAGE_2MB_SHIFT)
+#define SUPERPAGE_1GB_SHIFT   18
+#define SUPERPAGE_1GB_NR_PFNS (1UL << SUPERPAGE_1GB_SHIFT)
+
+#define SPECIALPAGE_PAGING   0
+#define SPECIALPAGE_ACCESS   1
+#define SPECIALPAGE_SHARING  2
+#define SPECIALPAGE_BUFIOREQ 3
+#define SPECIALPAGE_XENSTORE 4
+#define SPECIALPAGE_IOREQ    5
+#define SPECIALPAGE_IDENT_PT 6
+#define SPECIALPAGE_CONSOLE  7
+#define NR_SPECIAL_PAGES     8
+#define special_pfn(x) (0xff000u - NR_SPECIAL_PAGES + (x))
+
+static void build_hvm_info(void *hvm_info_page, uint64_t mem_size,
+                           uint64_t mmio_start, uint64_t mmio_size)
+{
+    struct hvm_info_table *hvm_info = (struct hvm_info_table *)
+        (((unsigned char *)hvm_info_page) + HVM_INFO_OFFSET);
+    uint64_t lowmem_end = mem_size, highmem_end = 0;
+    uint8_t sum;
+    int i;
+
+    if ( lowmem_end > mmio_start )
+    {
+        highmem_end = (1ull<<32) + (lowmem_end - mmio_start);
+        lowmem_end = mmio_start;
+    }
+
+    memset(hvm_info_page, 0, PAGE_SIZE);
+
+    /* Fill in the header. */
+    strncpy(hvm_info->signature, "HVM INFO", 8);
+    hvm_info->length = sizeof(struct hvm_info_table);
+
+    /* Sensible defaults: these can be overridden by the caller. */
+    hvm_info->apic_mode = 1;
+    hvm_info->nr_vcpus = 1;
+    memset(hvm_info->vcpu_online, 0xff, sizeof(hvm_info->vcpu_online));
+
+    /* Memory parameters. */
+    hvm_info->low_mem_pgend = lowmem_end >> PAGE_SHIFT;
+    hvm_info->high_mem_pgend = highmem_end >> PAGE_SHIFT;
+    hvm_info->reserved_mem_pgstart = special_pfn(0);
+
+    /* Finish with the checksum. */
+    for ( i = 0, sum = 0; i < hvm_info->length; i++ )
+        sum += ((uint8_t *)hvm_info)[i];
+    hvm_info->checksum = -sum;
+}
+
+static int loadelfimage(
+    xc_interface *xch,
+    struct elf_binary *elf, uint32_t dom, unsigned long *parray)
+{
+    privcmd_mmap_entry_t *entries = NULL;
+    unsigned long pfn_start = elf->pstart >> PAGE_SHIFT;
+    unsigned long pfn_end = (elf->pend + PAGE_SIZE - 1) >> PAGE_SHIFT;
+    size_t pages = pfn_end - pfn_start;
+    int i, rc = -1;
+
+    /* Map address space for initial elf image. */
+    entries = calloc(pages, sizeof(privcmd_mmap_entry_t));
+    if ( entries == NULL )
+        goto err;
+
+    for ( i = 0; i < pages; i++ )
+        entries[i].mfn = parray[(elf->pstart >> PAGE_SHIFT) + i];
+
+    elf->dest = xc_map_foreign_ranges(
+        xch, dom, pages << PAGE_SHIFT, PROT_READ | PROT_WRITE, 1 << PAGE_SHIFT,
+        entries, pages);
+    if ( elf->dest == NULL )
+        goto err;
+
+    elf->dest += elf->pstart & (PAGE_SIZE - 1);
+
+    /* Load the initial elf image. */
+    rc = elf_load_binary(elf);
+    if ( rc < 0 )
+        PERROR("Failed to load elf binary\n");
+
+    munmap(elf->dest, pages << PAGE_SHIFT);
+    elf->dest = NULL;
+
+ err:
+    free(entries);
+
+    return rc;
+}
+
+/*
+ * Check whether there exists mmio hole in the specified memory range.
+ * Returns 1 if exists, else returns 0.
+ */
+static int check_mmio_hole(uint64_t start, uint64_t memsize,
+                           uint64_t mmio_start, uint64_t mmio_size)
+{
+    if ( start + memsize <= mmio_start || start >= mmio_start + mmio_size )
+        return 0;
+    else
+        return 1;
+}
+
+static int setup_guest(xc_interface *xch,
+                       uint32_t dom, const struct xc_hvm_build_args *args,
+                       char *image, unsigned long image_size)
+{
+    xen_pfn_t *page_array = NULL;
+    unsigned long i, nr_pages = args->mem_size >> PAGE_SHIFT;
+    unsigned long target_pages = args->mem_target >> PAGE_SHIFT;
+    uint64_t mmio_start = (1ull << 32) - args->mmio_size;
+    uint64_t mmio_size = args->mmio_size;
+    unsigned long entry_eip, cur_pages, cur_pfn;
+    void *hvm_info_page;
+    uint32_t *ident_pt;
+    struct elf_binary elf;
+    uint64_t v_start, v_end;
+    int rc;
+    xen_capabilities_info_t caps;
+    unsigned long stat_normal_pages = 0, stat_2mb_pages = 0, 
+        stat_1gb_pages = 0;
+    int pod_mode = 0;
+
+    if ( nr_pages > target_pages )
+        pod_mode = 1;
+
+    memset(&elf, 0, sizeof(elf));
+    if ( elf_init(&elf, image, image_size) != 0 )
+        goto error_out;
+
+    xc_elf_set_logfile(xch, &elf, 1);
+
+    elf_parse_binary(&elf);
+    v_start = 0;
+    v_end = args->mem_size;
+
+    if ( xc_version(xch, XENVER_capabilities, &caps) != 0 )
+    {
+        PERROR("Could not get Xen capabilities");
+        goto error_out;
+    }
+
+    IPRINTF("VIRTUAL MEMORY ARRANGEMENT:\n"
+            "  Loader:        %016"PRIx64"->%016"PRIx64"\n"
+            "  TOTAL:         %016"PRIx64"->%016"PRIx64"\n"
+            "  ENTRY ADDRESS: %016"PRIx64"\n",
+            elf.pstart, elf.pend,
+            v_start, v_end,
+            elf_uval(&elf, elf.ehdr, e_entry));
+
+    if ( (page_array = malloc(nr_pages * sizeof(xen_pfn_t))) == NULL )
+    {
+        PERROR("Could not allocate memory.");
+        goto error_out;
+    }
+
+    for ( i = 0; i < nr_pages; i++ )
+        page_array[i] = i;
+    for ( i = mmio_start >> PAGE_SHIFT; i < nr_pages; i++ )
+        page_array[i] += mmio_size >> PAGE_SHIFT;
+
+    /*
+     * Allocate memory for HVM guest, skipping VGA hole 0xA0000-0xC0000.
+     *
+     * We attempt to allocate 1GB pages if possible. It falls back on 2MB
+     * pages if 1GB allocation fails. 4KB pages will be used eventually if
+     * both fail.
+     * 
+     * Under 2MB mode, we allocate pages in batches of no more than 8MB to 
+     * ensure that we can be preempted and hence dom0 remains responsive.
+     */
+    rc = xc_domain_populate_physmap_exact(
+        xch, dom, 0xa0, 0, 0, &page_array[0x00]);
+    cur_pages = 0xc0;
+    stat_normal_pages = 0xc0;
+    while ( (rc == 0) && (nr_pages > cur_pages) )
+    {
+        /* Clip count to maximum 1GB extent. */
+        unsigned long count = nr_pages - cur_pages;
+        unsigned long max_pages = SUPERPAGE_1GB_NR_PFNS;
+
+        if ( count > max_pages )
+            count = max_pages;
+
+        cur_pfn = page_array[cur_pages];
+
+        /* Take care the corner cases of super page tails */
+        if ( ((cur_pfn & (SUPERPAGE_1GB_NR_PFNS-1)) != 0) &&
+             (count > (-cur_pfn & (SUPERPAGE_1GB_NR_PFNS-1))) )
+            count = -cur_pfn & (SUPERPAGE_1GB_NR_PFNS-1);
+        else if ( ((count & (SUPERPAGE_1GB_NR_PFNS-1)) != 0) &&
+                  (count > SUPERPAGE_1GB_NR_PFNS) )
+            count &= ~(SUPERPAGE_1GB_NR_PFNS - 1);
+
+        /* Attemp to allocate 1GB super page. Because in each pass we only
+         * allocate at most 1GB, we don't have to clip super page boundaries.
+         */
+        if ( ((count | cur_pfn) & (SUPERPAGE_1GB_NR_PFNS - 1)) == 0 &&
+             /* Check if there exists MMIO hole in the 1GB memory range */
+             !check_mmio_hole(cur_pfn << PAGE_SHIFT,
+                              SUPERPAGE_1GB_NR_PFNS << PAGE_SHIFT,
+                              mmio_start, mmio_size) )
+        {
+            long done;
+            unsigned long nr_extents = count >> SUPERPAGE_1GB_SHIFT;
+            xen_pfn_t sp_extents[nr_extents];
+
+            for ( i = 0; i < nr_extents; i++ )
+                sp_extents[i] = page_array[cur_pages+(i<<SUPERPAGE_1GB_SHIFT)];
+
+            done = xc_domain_populate_physmap(xch, dom, nr_extents, SUPERPAGE_1GB_SHIFT,
+                                              pod_mode ? XENMEMF_populate_on_demand : 0,
+                                              sp_extents);
+
+            if ( done > 0 )
+            {
+                stat_1gb_pages += done;
+                done <<= SUPERPAGE_1GB_SHIFT;
+                cur_pages += done;
+                count -= done;
+            }
+        }
+
+        if ( count != 0 )
+        {
+            /* Clip count to maximum 8MB extent. */
+            max_pages = SUPERPAGE_2MB_NR_PFNS * 4;
+            if ( count > max_pages )
+                count = max_pages;
+            
+            /* Clip partial superpage extents to superpage boundaries. */
+            if ( ((cur_pfn & (SUPERPAGE_2MB_NR_PFNS-1)) != 0) &&
+                 (count > (-cur_pfn & (SUPERPAGE_2MB_NR_PFNS-1))) )
+                count = -cur_pfn & (SUPERPAGE_2MB_NR_PFNS-1);
+            else if ( ((count & (SUPERPAGE_2MB_NR_PFNS-1)) != 0) &&
+                      (count > SUPERPAGE_2MB_NR_PFNS) )
+                count &= ~(SUPERPAGE_2MB_NR_PFNS - 1); /* clip non-s.p. tail */
+
+            /* Attempt to allocate superpage extents. */
+            if ( ((count | cur_pfn) & (SUPERPAGE_2MB_NR_PFNS - 1)) == 0 )
+            {
+                long done;
+                unsigned long nr_extents = count >> SUPERPAGE_2MB_SHIFT;
+                xen_pfn_t sp_extents[nr_extents];
+
+                for ( i = 0; i < nr_extents; i++ )
+                    sp_extents[i] = page_array[cur_pages+(i<<SUPERPAGE_2MB_SHIFT)];
+
+                done = xc_domain_populate_physmap(xch, dom, nr_extents, SUPERPAGE_2MB_SHIFT,
+                                                  pod_mode ? XENMEMF_populate_on_demand : 0,
+                                                  sp_extents);
+
+                if ( done > 0 )
+                {
+                    stat_2mb_pages += done;
+                    done <<= SUPERPAGE_2MB_SHIFT;
+                    cur_pages += done;
+                    count -= done;
+                }
+            }
+        }
+
+        /* Fall back to 4kB extents. */
+        if ( count != 0 )
+        {
+            rc = xc_domain_populate_physmap_exact(
+                xch, dom, count, 0, 0, &page_array[cur_pages]);
+            cur_pages += count;
+            stat_normal_pages += count;
+        }
+    }
+
+    /* Subtract 0x20 from target_pages for the VGA "hole".  Xen will
+     * adjust the PoD cache size so that domain tot_pages will be
+     * target_pages - 0x20 after this call. */
+    if ( pod_mode )
+        rc = xc_domain_set_pod_target(xch, dom, target_pages - 0x20,
+                                      NULL, NULL, NULL);
+
+    if ( rc != 0 )
+    {
+        PERROR("Could not allocate memory for HVM guest.");
+        goto error_out;
+    }
+
+    IPRINTF("PHYSICAL MEMORY ALLOCATION:\n"
+            "  4KB PAGES: 0x%016lx\n"
+            "  2MB PAGES: 0x%016lx\n"
+            "  1GB PAGES: 0x%016lx\n",
+            stat_normal_pages, stat_2mb_pages, stat_1gb_pages);
+    
+    if ( loadelfimage(xch, &elf, dom, page_array) != 0 )
+        goto error_out;
+
+    if ( (hvm_info_page = xc_map_foreign_range(
+              xch, dom, PAGE_SIZE, PROT_READ | PROT_WRITE,
+              HVM_INFO_PFN)) == NULL )
+        goto error_out;
+    build_hvm_info(hvm_info_page, v_end, mmio_start, mmio_size);
+    munmap(hvm_info_page, PAGE_SIZE);
+
+    /* Allocate and clear special pages. */
+    for ( i = 0; i < NR_SPECIAL_PAGES; i++ )
+    {
+        xen_pfn_t pfn = special_pfn(i);
+        rc = xc_domain_populate_physmap_exact(xch, dom, 1, 0, 0, &pfn);
+        if ( rc != 0 )
+        {
+            PERROR("Could not allocate %d'th special page.", i);
+            goto error_out;
+        }
+        if ( xc_clear_domain_page(xch, dom, special_pfn(i)) )
+            goto error_out;
+    }
+
+    xc_set_hvm_param(xch, dom, HVM_PARAM_STORE_PFN,
+                     special_pfn(SPECIALPAGE_XENSTORE));
+    xc_set_hvm_param(xch, dom, HVM_PARAM_BUFIOREQ_PFN,
+                     special_pfn(SPECIALPAGE_BUFIOREQ));
+    xc_set_hvm_param(xch, dom, HVM_PARAM_IOREQ_PFN,
+                     special_pfn(SPECIALPAGE_IOREQ));
+    xc_set_hvm_param(xch, dom, HVM_PARAM_CONSOLE_PFN,
+                     special_pfn(SPECIALPAGE_CONSOLE));
+    xc_set_hvm_param(xch, dom, HVM_PARAM_PAGING_RING_PFN,
+                     special_pfn(SPECIALPAGE_PAGING));
+    xc_set_hvm_param(xch, dom, HVM_PARAM_ACCESS_RING_PFN,
+                     special_pfn(SPECIALPAGE_ACCESS));
+    xc_set_hvm_param(xch, dom, HVM_PARAM_SHARING_RING_PFN,
+                     special_pfn(SPECIALPAGE_SHARING));
+
+    /*
+     * Identity-map page table is required for running with CR0.PG=0 when
+     * using Intel EPT. Create a 32-bit non-PAE page directory of superpages.
+     */
+    if ( (ident_pt = xc_map_foreign_range(
+              xch, dom, PAGE_SIZE, PROT_READ | PROT_WRITE,
+              special_pfn(SPECIALPAGE_IDENT_PT))) == NULL )
+        goto error_out;
+    for ( i = 0; i < PAGE_SIZE / sizeof(*ident_pt); i++ )
+        ident_pt[i] = ((i << 22) | _PAGE_PRESENT | _PAGE_RW | _PAGE_USER |
+                       _PAGE_ACCESSED | _PAGE_DIRTY | _PAGE_PSE);
+    munmap(ident_pt, PAGE_SIZE);
+    xc_set_hvm_param(xch, dom, HVM_PARAM_IDENT_PT,
+                     special_pfn(SPECIALPAGE_IDENT_PT) << PAGE_SHIFT);
+
+    /* Insert JMP <rel32> instruction at address 0x0 to reach entry point. */
+    entry_eip = elf_uval(&elf, elf.ehdr, e_entry);
+    if ( entry_eip != 0 )
+    {
+        char *page0 = xc_map_foreign_range(
+            xch, dom, PAGE_SIZE, PROT_READ | PROT_WRITE, 0);
+        if ( page0 == NULL )
+            goto error_out;
+        page0[0] = 0xe9;
+        *(uint32_t *)&page0[1] = entry_eip - 5;
+        munmap(page0, PAGE_SIZE);
+    }
+
+    free(page_array);
+    return 0;
+
+ error_out:
+    free(page_array);
+    return -1;
+}
+
+/* xc_hvm_build:
+ * Create a domain for a virtualized Linux, using files/filenames.
+ */
+int xc_hvm_build(xc_interface *xch, uint32_t domid,
+                 const struct xc_hvm_build_args *hvm_args)
+{
+    struct xc_hvm_build_args args = *hvm_args;
+    void *image;
+    unsigned long image_size;
+    int sts;
+
+    if ( domid == 0 )
+        return -1;
+    if ( args.image_file_name == NULL )
+        return -1;
+
+    if ( args.mem_target == 0 )
+        args.mem_target = args.mem_size;
+
+    if ( args.mmio_size == 0 )
+        args.mmio_size = HVM_BELOW_4G_MMIO_LENGTH;
+
+    /* An HVM guest must be initialised with at least 2MB memory. */
+    if ( args.mem_size < (2ull << 20) || args.mem_target < (2ull << 20) )
+        return -1;
+
+    image = xc_read_image(xch, args.image_file_name, &image_size);
+    if ( image == NULL )
+        return -1;
+
+    sts = setup_guest(xch, domid, &args, image, image_size);
+
+    free(image);
+
+    return sts;
+}
+
+/* xc_hvm_build_target_mem: 
+ * Create a domain for a pre-ballooned virtualized Linux, using
+ * files/filenames.  If target < memsize, domain is created with
+ * memsize pages marked populate-on-demand, 
+ * calculating pod cache size based on target.
+ * If target == memsize, pages are populated normally.
+ */
+int xc_hvm_build_target_mem(xc_interface *xch,
+                           uint32_t domid,
+                           int memsize,
+                           int target,
+                           const char *image_name)
+{
+    struct xc_hvm_build_args args = {};
+
+    args.mem_size = (uint64_t)memsize << 20;
+    args.mem_target = (uint64_t)target << 20;
+    args.image_file_name = image_name;
+
+    return xc_hvm_build(xch, domid, &args);
+}
+
+/*
+ * Local variables:
+ * mode: C
+ * c-set-style: "BSD"
+ * c-basic-offset: 4
+ * tab-width: 4
+ * indent-tabs-mode: nil
+ * End:
+ */