diff mbox series

[5/5] xen/arm: do not give memory back to static heap

Message ID 20241115105036.218418-6-luca.fancellu@arm.com (mailing list archive)
State New
Headers show
Series Prerequisite patches for R82 upstreaming | expand

Commit Message

Luca Fancellu Nov. 15, 2024, 10:50 a.m. UTC 
From: Penny Zheng <Penny.Zheng@arm.com>

If Xenheap is statically configured in Device Tree, its size is
definite. So, the memory shall not be given back into static heap, like
it's normally done in free_init_memory, etc, once the initialization
is finished.

Extract static_heap flag from init data bootinfo, as it will be needed
after destroying the init data section.
Introduce a new helper xen_is_using_staticheap() to tell whether Xenheap
is statically configured in the Device Tree.

Signed-off-by: Luca Fancellu <luca.fancellu@arm.com>
---
This is a rebase of this one: https://patchwork.kernel.org/project/xen-devel/patch/20230626033443.2943270-18-Penny.Zheng@arm.com/
---
 xen/arch/arm/arm32/mmu/mm.c          |  4 ++--
 xen/arch/arm/kernel.c                |  3 ++-
 xen/arch/arm/mmu/setup.c             |  8 ++++++--
 xen/arch/arm/setup.c                 | 27 ++++++++++++++-------------
 xen/common/device-tree/bootfdt.c     |  2 +-
 xen/common/device-tree/bootinfo.c    |  2 +-
 xen/common/device-tree/device-tree.c |  3 +++
 xen/include/xen/bootfdt.h            | 11 ++++++++++-
 8 files changed, 39 insertions(+), 21 deletions(-)
diff mbox series

Patch

diff --git a/xen/arch/arm/arm32/mmu/mm.c b/xen/arch/arm/arm32/mmu/mm.c
index 063611412be0..b7ca7c94c9ca 100644
--- a/xen/arch/arm/arm32/mmu/mm.c
+++ b/xen/arch/arm/arm32/mmu/mm.c
@@ -199,7 +199,7 @@  void __init setup_mm(void)
 
     total_pages = ram_size >> PAGE_SHIFT;
 
-    if ( bootinfo.static_heap )
+    if ( xen_is_using_staticheap() )
     {
         const struct membanks *reserved_mem = bootinfo_get_reserved_mem();
 
@@ -246,7 +246,7 @@  void __init setup_mm(void)
 
     do
     {
-        e = bootinfo.static_heap ?
+        e = xen_is_using_staticheap() ?
             fit_xenheap_in_static_heap(pfn_to_paddr(xenheap_pages), MB(32)) :
             consider_modules(ram_start, ram_end,
                              pfn_to_paddr(xenheap_pages),
diff --git a/xen/arch/arm/kernel.c b/xen/arch/arm/kernel.c
index 293d7efaed9c..a4a99607b668 100644
--- a/xen/arch/arm/kernel.c
+++ b/xen/arch/arm/kernel.c
@@ -247,7 +247,8 @@  static __init int kernel_decompress(struct bootmodule *mod, uint32_t offset)
      * Free the original kernel, update the pointers to the
      * decompressed kernel
      */
-    fw_unreserved_regions(addr, addr + size, init_domheap_pages, 0);
+    if ( !xen_is_using_staticheap() )
+        fw_unreserved_regions(addr, addr + size, init_domheap_pages, 0);
 
     return 0;
 }
diff --git a/xen/arch/arm/mmu/setup.c b/xen/arch/arm/mmu/setup.c
index 1b1d302c8788..d0775793f4b4 100644
--- a/xen/arch/arm/mmu/setup.c
+++ b/xen/arch/arm/mmu/setup.c
@@ -343,8 +343,12 @@  void free_init_memory(void)
     if ( rc )
         panic("Unable to remove the init section (rc = %d)\n", rc);
 
-    init_domheap_pages(pa, pa + len);
-    printk("Freed %ldkB init memory.\n", (long)(__init_end-__init_begin)>>10);
+    if ( !xen_is_using_staticheap() )
+    {
+        init_domheap_pages(pa, pa + len);
+        printk("Freed %ldkB init memory.\n",
+               (long)(__init_end-__init_begin) >> 10);
+    }
 }
 
 /**
diff --git a/xen/arch/arm/setup.c b/xen/arch/arm/setup.c
index 71ebaa77ca94..91340d5dc201 100644
--- a/xen/arch/arm/setup.c
+++ b/xen/arch/arm/setup.c
@@ -206,24 +206,25 @@  void __init discard_initial_modules(void)
     struct bootmodules *mi = &bootinfo.modules;
     int i;
 
-    for ( i = 0; i < mi->nr_mods; i++ )
+    if ( !xen_is_using_staticheap() )
     {
-        paddr_t s = mi->module[i].start;
-        paddr_t e = s + PAGE_ALIGN(mi->module[i].size);
-
-        if ( mi->module[i].kind == BOOTMOD_XEN )
-            continue;
+        for ( i = 0; i < mi->nr_mods; i++ )
+        {
+            paddr_t s = mi->module[i].start;
+            paddr_t e = s + PAGE_ALIGN(mi->module[i].size);
 
-        if ( !mfn_valid(maddr_to_mfn(s)) ||
-             !mfn_valid(maddr_to_mfn(e)) )
-            continue;
+            if ( mi->module[i].kind == BOOTMOD_XEN )
+                continue;
 
-        fw_unreserved_regions(s, e, init_domheap_pages, 0);
-    }
+            if ( !mfn_valid(maddr_to_mfn(s)) ||
+                 !mfn_valid(maddr_to_mfn(e)) )
+                continue;
 
-    mi->nr_mods = 0;
+            fw_unreserved_regions(s, e, init_domheap_pages, 0);
+        }
 
-    remove_early_mappings();
+        mi->nr_mods = 0;
+    }
 }
 
 /* Relocate the FDT in Xen heap */
diff --git a/xen/common/device-tree/bootfdt.c b/xen/common/device-tree/bootfdt.c
index 927f59c64b0d..ccb150b34a63 100644
--- a/xen/common/device-tree/bootfdt.c
+++ b/xen/common/device-tree/bootfdt.c
@@ -403,7 +403,7 @@  static int __init process_chosen_node(const void *fdt, int node,
         if ( rc )
             return rc;
 
-        bootinfo.static_heap = true;
+        static_heap = true;
     }
 
     printk("Checking for initrd in /chosen\n");
diff --git a/xen/common/device-tree/bootinfo.c b/xen/common/device-tree/bootinfo.c
index f2e6a1145b7c..1e83d5172938 100644
--- a/xen/common/device-tree/bootinfo.c
+++ b/xen/common/device-tree/bootinfo.c
@@ -386,7 +386,7 @@  void __init populate_boot_allocator(void)
     const struct membanks *reserved_mem = bootinfo_get_reserved_mem();
     paddr_t s, e;
 
-    if ( bootinfo.static_heap )
+    if ( xen_is_using_staticheap() )
     {
         for ( i = 0 ; i < reserved_mem->nr_banks; i++ )
         {
diff --git a/xen/common/device-tree/device-tree.c b/xen/common/device-tree/device-tree.c
index d0528c582565..22b69c49171b 100644
--- a/xen/common/device-tree/device-tree.c
+++ b/xen/common/device-tree/device-tree.c
@@ -25,6 +25,9 @@ 
 #include <asm/setup.h>
 #include <xen/err.h>
 
+/* Flag saved when Xen is using the static heap feature (xen,static-heap) */
+bool __read_mostly static_heap;
+
 const void *device_tree_flattened;
 dt_irq_xlate_func dt_irq_xlate;
 /* Host device tree */
diff --git a/xen/include/xen/bootfdt.h b/xen/include/xen/bootfdt.h
index 16fa05f38f38..0015a4babde7 100644
--- a/xen/include/xen/bootfdt.h
+++ b/xen/include/xen/bootfdt.h
@@ -132,7 +132,6 @@  struct bootinfo {
 #ifdef CONFIG_STATIC_SHM
     struct shared_meminfo shmem;
 #endif
-    bool static_heap;
 };
 
 #ifdef CONFIG_ACPI
@@ -156,6 +155,7 @@  struct bootinfo {
 }
 
 extern struct bootinfo bootinfo;
+extern bool static_heap;
 
 bool check_reserved_regions_overlap(paddr_t region_start,
                                     paddr_t region_size);
@@ -206,4 +206,13 @@  static inline struct shmem_membank_extra *bootinfo_get_shmem_extra(void)
 }
 #endif
 
+static inline bool xen_is_using_staticheap(void)
+{
+#ifdef CONFIG_STATIC_MEMORY
+    return static_heap;
+#else
+    return false;
+#endif
+}
+
 #endif /* XEN_BOOTFDT_H */