[PATCH 16/18 V2]: PVH xen: elf changes to pref for dom0 PVH.

[Mukesh Rathor <mukesh.rathor@oracle.com>]

 This patch prepares for dom0 PVH by making some changes in the elf
 code; add a new parameter to indicate PVH dom0 and use different copy
 function for PVH. Also, add check in iommu.c to check for iommu
 enabled for dom0 PVH.

Changes in V2: None

Signed-off-by: Mukesh Rathor <mukesh.rathor@oracle.com>
---
 xen/arch/x86/domain_build.c       |    2 +-
 xen/common/libelf/libelf-loader.c |   51 ++++++++++++++++++++++++++++++++++---
 xen/drivers/passthrough/iommu.c   |   18 +++++++++++-
 xen/include/xen/libelf.h          |    3 +-
 4 files changed, 66 insertions(+), 8 deletions(-)

diff --git a/xen/arch/x86/domain_build.c b/xen/arch/x86/domain_build.c
index c8f435d..8c5b27a 100644
--- a/xen/arch/x86/domain_build.c
+++ b/xen/arch/x86/domain_build.c
@@ -766,7 +766,7 @@ int __init construct_dom0(
 
     /* Copy the OS image and free temporary buffer. */
     elf.dest = (void*)vkern_start;
-    rc = elf_load_binary(&elf);
+    rc = elf_load_binary(&elf, 0);
     if ( rc < 0 )
     {
         printk("Failed to load the kernel binary\n");
diff --git a/xen/common/libelf/libelf-loader.c b/xen/common/libelf/libelf-loader.c
index 3cf9c59..d732f75 100644
--- a/xen/common/libelf/libelf-loader.c
+++ b/xen/common/libelf/libelf-loader.c
@@ -17,6 +17,10 @@
  */
 
 #include "libelf-private.h"
+#ifdef __XEN__
+#include <public/xen.h>
+#include <asm/debugger.h>
+#endif
 
 /* ------------------------------------------------------------------------ */
 
@@ -108,7 +112,8 @@ void elf_set_log(struct elf_binary *elf, elf_log_callback *log_callback,
     elf->verbose = verbose;
 }
 
-static int elf_load_image(void *dst, const void *src, uint64_t filesz, uint64_t memsz)
+static int elf_load_image(void *dst, const void *src, uint64_t filesz, 
+                          uint64_t memsz, int not_used)
 {
     memcpy(dst, src, filesz);
     memset(dst + filesz, 0, memsz - filesz);
@@ -122,11 +127,34 @@ void elf_set_verbose(struct elf_binary *elf)
     elf->verbose = 1;
 }
 
-static int elf_load_image(void *dst, const void *src, uint64_t filesz, uint64_t memsz)
+static int elf_load_image(void *dst, const void *src, uint64_t filesz, 
+                          uint64_t memsz, int is_pvh_dom0)
 {
     int rc;
     if ( filesz > ULONG_MAX || memsz > ULONG_MAX )
         return -1;
+
+    /* raw_copy_to_guest -> copy_to_user_hvm -> __hvm_copy needs curr to
+     * point to the hvm/pvh vcpu. Hence for PVH dom0 we can't use that. For now
+     * just use dbg_rw_mem(). */
+    if ( is_pvh_dom0 ) 
+    {
+        int j, rem; 
+        rem = dbg_rw_mem((dbgva_t)dst, (dbgbyte_t *)src, (int)filesz, 0, 1, 0);
+        if ( rem ) {
+            printk("Failed to copy elf binary. len:%ld rem:%d\n", filesz, rem);
+            return -1;
+        }
+        for (j=0; j < memsz - filesz; j++) {
+            unsigned char zero=0;
+            rem = dbg_rw_mem((dbgva_t)(dst+filesz+j), &zero, 1, 0, 1, 0);
+            if (rem) {
+                printk("Failed to copy to:%p rem:%d\n", dst+filesz+j, rem);
+                return -1;
+            }
+        }
+        return 0;
+    }
     rc = raw_copy_to_guest(dst, src, filesz);
     if ( rc != 0 )
         return -1;
@@ -260,7 +288,9 @@ void elf_parse_binary(struct elf_binary *elf)
             __FUNCTION__, elf->pstart, elf->pend);
 }
 
-int elf_load_binary(struct elf_binary *elf)
+/* This function called from the libraries when building guests, and also for
+ * dom0 from construct_dom0().   */
+static int _elf_load_binary(struct elf_binary *elf, int is_pvh_dom0)
 {
     const elf_phdr *phdr;
     uint64_t i, count, paddr, offset, filesz, memsz;
@@ -279,7 +309,8 @@ int elf_load_binary(struct elf_binary *elf)
         dest = elf_get_ptr(elf, paddr);
         elf_msg(elf, "%s: phdr %" PRIu64 " at 0x%p -> 0x%p\n",
                 __func__, i, dest, dest + filesz);
-        if ( elf_load_image(dest, elf->image + offset, filesz, memsz) != 0 )
+        if ( elf_load_image(dest, elf->image + offset, filesz, memsz, 
+                            is_pvh_dom0) != 0 )
             return -1;
     }
 
@@ -287,6 +318,18 @@ int elf_load_binary(struct elf_binary *elf)
     return 0;
 }
 
+#ifdef __XEN__
+int elf_load_binary(struct elf_binary *elf, int is_pvh_dom0)
+{
+    return _elf_load_binary(elf, is_pvh_dom0);
+}
+#else
+int elf_load_binary(struct elf_binary *elf)
+{
+    return _elf_load_binary(elf, 0);
+}
+#endif
+
 void *elf_get_ptr(struct elf_binary *elf, unsigned long addr)
 {
     return elf->dest + addr - elf->pstart;
diff --git a/xen/drivers/passthrough/iommu.c b/xen/drivers/passthrough/iommu.c
index c1d3c12..9954e07 100644
--- a/xen/drivers/passthrough/iommu.c
+++ b/xen/drivers/passthrough/iommu.c
@@ -125,15 +125,25 @@ int iommu_domain_init(struct domain *d)
     return hd->platform_ops->init(d);
 }
 
+static inline void check_dom0_pvh_reqs(struct domain *d)
+{
+    if (!iommu_enabled || iommu_passthrough)
+        panic("For pvh dom0, iommu must be enabled, dom0-passthrough must "
+              "not be enabled \n");
+}
+
 void __init iommu_dom0_init(struct domain *d)
 {
     struct hvm_iommu *hd = domain_hvm_iommu(d);
 
+    if ( is_pvh_domain(d) )
+        check_dom0_pvh_reqs(d);
+
     if ( !iommu_enabled )
         return;
 
     register_keyhandler('o', &iommu_p2m_table);
-    d->need_iommu = !!iommu_dom0_strict;
+    d->need_iommu = is_pvh_domain(d) || !!iommu_dom0_strict;
     if ( need_iommu(d) )
     {
         struct page_info *page;
@@ -146,7 +156,11 @@ void __init iommu_dom0_init(struct domain *d)
                  ((page->u.inuse.type_info & PGT_type_mask)
                   == PGT_writable_page) )
                 mapping |= IOMMUF_writable;
-            hd->platform_ops->map_page(d, mfn, mfn, mapping);
+            if ( is_pvh_domain(d) ) {
+                unsigned long gfn = mfn_to_gfn(d, _mfn(mfn));
+                hd->platform_ops->map_page(d, gfn, mfn, mapping);
+            } else
+                hd->platform_ops->map_page(d, mfn, mfn, mapping);
             if ( !(i++ & 0xfffff) )
                 process_pending_softirqs();
         }
diff --git a/xen/include/xen/libelf.h b/xen/include/xen/libelf.h
index 218bb18..2dc2bdb 100644
--- a/xen/include/xen/libelf.h
+++ b/xen/include/xen/libelf.h
@@ -192,13 +192,14 @@ int elf_phdr_is_loadable(struct elf_binary *elf, const elf_phdr * phdr);
 int elf_init(struct elf_binary *elf, const char *image, size_t size);
 #ifdef __XEN__
 void elf_set_verbose(struct elf_binary *elf);
+int elf_load_binary(struct elf_binary *elf, int is_pvh_dom0);
 #else
 void elf_set_log(struct elf_binary *elf, elf_log_callback*,
                  void *log_caller_pointer, int verbose);
+int elf_load_binary(struct elf_binary *elf);
 #endif
 
 void elf_parse_binary(struct elf_binary *elf);
-int elf_load_binary(struct elf_binary *elf);
 
 void *elf_get_ptr(struct elf_binary *elf, unsigned long addr);
 uint64_t elf_lookup_addr(struct elf_binary *elf, const char *symbol);
-- 
1.7.2.3