[Xen-devel] [v5][PATCH 13/16] libxl: construct e820 map with RDM information for HVM guest

[Tiejun Chen <tiejun.chen@xxxxxxxxx>]

Here we'll construct a basic guest e820 table via
XENMEM_set_memory_map. This table includes lowmem, highmem
and RDMs if they exist, and hvmloader would need this info
later.

Note this guest e820 table would be same as before if the
platform has no any RDM or we disable RDM (by default).

CC: Ian Jackson <ian.jackson@xxxxxxxxxxxxx>
CC: Stefano Stabellini <stefano.stabellini@xxxxxxxxxxxxx>
CC: Ian Campbell <ian.campbell@xxxxxxxxxx>
CC: Wei Liu <wei.liu2@xxxxxxxxxx>
Signed-off-by: Tiejun Chen <tiejun.chen@xxxxxxxxx>
---
v5:

* Rephrase patch's short log
* Make libxl__domain_construct_e820() hidden

v4:

* Use goto style error handling.
* Instead of NOGC, we shoud use libxl__malloc(gc,XXX) to allocate local e820.

 tools/libxl/libxl_dom.c      |  5 +++
 tools/libxl/libxl_internal.h | 24 +++++++++++++
 tools/libxl/libxl_x86.c      | 83 ++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 112 insertions(+)

diff --git a/tools/libxl/libxl_dom.c b/tools/libxl/libxl_dom.c
index 62ef120..41da479 100644
--- a/tools/libxl/libxl_dom.c
+++ b/tools/libxl/libxl_dom.c
@@ -1004,6 +1004,11 @@ int libxl__build_hvm(libxl__gc *gc, uint32_t domid,
         goto out;
     }
 
+    if (libxl__domain_construct_e820(gc, d_config, domid, &args)) {
+        LOG(ERROR, "setting domain memory map failed");
+        goto out;
+    }
+
     ret = hvm_build_set_params(ctx->xch, domid, info, state->store_port,
                                &state->store_mfn, state->console_port,
                                &state->console_mfn, state->store_domid,
diff --git a/tools/libxl/libxl_internal.h b/tools/libxl/libxl_internal.h
index b4d8419..a50449a 100644
--- a/tools/libxl/libxl_internal.h
+++ b/tools/libxl/libxl_internal.h
@@ -3794,6 +3794,30 @@ static inline void libxl__update_config_vtpm(libxl__gc 
*gc,
  */
 void libxl__bitmap_copy_best_effort(libxl__gc *gc, libxl_bitmap *dptr,
                                     const libxl_bitmap *sptr);
+
+/*
+ * Here we're just trying to set these kinds of e820 mappings:
+ *
+ * #1. Low memory region
+ *
+ * Low RAM starts at least from 1M to make sure all standard regions
+ * of the PC memory map, like BIOS, VGA memory-mapped I/O and vgabios,
+ * have enough space.
+ * Note: Those stuffs below 1M are still constructed with multiple
+ * e820 entries by hvmloader. At this point we don't change anything.
+ *
+ * #2. RDM region if it exists
+ *
+ * #3. High memory region if it exists
+ *
+ * Note: these regions are not overlapping since we already check
+ * to adjust them. Please refer to libxl__domain_device_construct_rdm().
+ */
+_hidden int libxl__domain_construct_e820(libxl__gc *gc,
+                                 libxl_domain_config *d_config,
+                                 uint32_t domid,
+                                 struct xc_hvm_build_args *args);
+
 #endif
 
 /*
diff --git a/tools/libxl/libxl_x86.c b/tools/libxl/libxl_x86.c
index ed2bd38..be297b2 100644
--- a/tools/libxl/libxl_x86.c
+++ b/tools/libxl/libxl_x86.c
@@ -438,6 +438,89 @@ int libxl__arch_domain_map_irq(libxl__gc *gc, uint32_t 
domid, int irq)
 }
 
 /*
+ * Here we're just trying to set these kinds of e820 mappings:
+ *
+ * #1. Low memory region
+ *
+ * Low RAM starts at least from 1M to make sure all standard regions
+ * of the PC memory map, like BIOS, VGA memory-mapped I/O and vgabios,
+ * have enough space.
+ * Note: Those stuffs below 1M are still constructed with multiple
+ * e820 entries by hvmloader. At this point we don't change anything.
+ *
+ * #2. RDM region if it exists
+ *
+ * #3. High memory region if it exists
+ *
+ * Note: these regions are not overlapping since we already check
+ * to adjust them. Please refer to libxl__domain_device_construct_rdm().
+ */
+#define GUEST_LOW_MEM_START_DEFAULT 0x100000
+int libxl__domain_construct_e820(libxl__gc *gc,
+                                 libxl_domain_config *d_config,
+                                 uint32_t domid,
+                                 struct xc_hvm_build_args *args)
+{
+    int rc = 0;
+    unsigned int nr = 0, i;
+    /* We always own at least one lowmem entry. */
+    unsigned int e820_entries = 1;
+    struct e820entry *e820 = NULL;
+    uint64_t highmem_size =
+                    args->highmem_end ? args->highmem_end - (1ull << 32) : 0;
+
+    /* Add all rdm entries. */
+    for (i = 0; i < d_config->num_rdms; i++)
+        if (d_config->rdms[i].flag != LIBXL_RDM_RESERVE_FLAG_INVALID)
+            e820_entries++;
+
+
+    /* If we should have a highmem range. */
+    if (highmem_size)
+        e820_entries++;
+
+    if (e820_entries >= E820MAX) {
+        LOG(ERROR, "Ooops! Too many entries in the memory map!\n");
+        rc = ERROR_INVAL;
+        goto out;
+    }
+
+    e820 = libxl__malloc(gc, sizeof(struct e820entry) * e820_entries);
+
+    /* Low memory */
+    e820[nr].addr = GUEST_LOW_MEM_START_DEFAULT;
+    e820[nr].size = args->lowmem_end - GUEST_LOW_MEM_START_DEFAULT;
+    e820[nr].type = E820_RAM;
+    nr++;
+
+    /* RDM mapping */
+    for (i = 0; i < d_config->num_rdms; i++) {
+        if (d_config->rdms[i].flag == LIBXL_RDM_RESERVE_FLAG_INVALID)
+            continue;
+
+        e820[nr].addr = d_config->rdms[i].start;
+        e820[nr].size = d_config->rdms[i].size;
+        e820[nr].type = E820_RESERVED;
+        nr++;
+    }
+
+    /* High memory */
+    if (highmem_size) {
+        e820[nr].addr = ((uint64_t)1 << 32);
+        e820[nr].size = highmem_size;
+        e820[nr].type = E820_RAM;
+    }
+
+    if (xc_domain_set_memory_map(CTX->xch, domid, e820, e820_entries) != 0) {
+        rc = ERROR_FAIL;
+        goto out;
+    }
+
+out:
+    return rc;
+}
+
+/*
  * Local variables:
  * mode: C
  * c-basic-offset: 4
-- 
1.9.1


_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel