libsys: mark regions allocated for DMA as special

This ensures that they will not be relocated.

Edited by David van Moolenbroek.

Change-Id: Ic2a97bc65b94dfcf364c06577aa340a9a5299e74

diff --git a/minix/include/minix/sef.h b/minix/include/minix/sef.h
index 395bc803fb9fa98c5fb01912b0d8d4d6d6bb0b6a..49202ad9f9e7ffda2baf001cb1f92be695e6e5da 100644 (file)
--- a/minix/include/minix/sef.h
+++ b/minix/include/minix/sef.h
@@ -366,6 +366,9 @@ void sef_llvm_stack_refs_restore(char *stack_buff);
 int sef_llvm_state_transfer(sef_init_info_t *info);
 int sef_llvm_add_special_mem_region(void *addr, size_t len, const char* name);
 int sef_llvm_del_special_mem_region_by_addr(void *addr);
+void *sef_llvm_ac_mmap(void *buf, size_t len, int prot, int flags, int fd,
+       off_t offset);
+int sef_llvm_ac_munmap(void *buf, size_t len);
 
 int sef_llvm_ltckpt_enabled(void);
 int sef_llvm_get_ltckpt_offset(void);

diff --git a/minix/lib/libsys/alloc_util.c b/minix/lib/libsys/alloc_util.c
index 6aff230862eeb0647f9577dfd28e4646eca091ae..e09bb8e76b35513e3954133686e2d2220afb67b0 100644 (file)
--- a/minix/lib/libsys/alloc_util.c
+++ b/minix/lib/libsys/alloc_util.c
@@ -8,7 +8,7 @@
 
 void *alloc_contig(size_t len, int flags, phys_bytes *phys)
 {
-       vir_bytes buf;
+       void* buf;
        int mmapflags = MAP_PREALLOC|MAP_CONTIG|MAP_ANON;
 
        if(flags & AC_LOWER16M)
@@ -23,21 +23,21 @@ void *alloc_contig(size_t len, int flags, phys_bytes *phys)
         * pre-allocated and contiguous.
         */
        errno = 0;
-       buf = (vir_bytes) mmap(0, len, PROT_READ|PROT_WRITE, mmapflags, -1, 0);
-
-       if(buf == (vir_bytes) MAP_FAILED) {
+       buf = sef_llvm_ac_mmap(0, len, PROT_READ|PROT_WRITE, mmapflags, -1, 0);
+       if(buf == MAP_FAILED) {
                return NULL;
        }
 
        /* Get physical address, if requested. */
-        if(phys != NULL && sys_umap(SELF, VM_D, buf, len, phys) != OK)
+        if(phys != NULL && sys_umap(SELF, VM_D, (vir_bytes)buf, len,
+           phys) != OK)
                panic("sys_umap_data_fb failed");
 
-       return (void *) buf;
+       return buf;
 }
 
 int free_contig(void *addr, size_t len)
 {
-       return munmap(addr, len);
+       return sef_llvm_ac_munmap(addr, len);
 }
 

diff --git a/minix/lib/libsys/sef_llvm.c b/minix/lib/libsys/sef_llvm.c
index 15cf4236e2195066344aacd90c8f60892c2de3f3..4f08fd9721a77dd86f3513fb01900c35ccc42fd9 100644 (file)
--- a/minix/lib/libsys/sef_llvm.c
+++ b/minix/lib/libsys/sef_llvm.c
@@ -153,6 +153,46 @@ int sef_llvm_del_special_mem_region_by_addr(void *addr)
     return st_del_special_mmapped_region_by_addr(addr);
 }
 
+/*===========================================================================*
+ *                             sef_llvm_ac_mmap                             *
+ *===========================================================================*/
+void* sef_llvm_ac_mmap(void *buf, size_t len, int prot, int flags, int fd,
+       off_t offset)
+{
+    int r;
+    extern void* __attribute__((weak))
+       _magic_real_mmap(void*, size_t, int, int, int, off_t);
+    if (!_magic_real_mmap)
+        return mmap(buf, len, prot, flags, fd, offset);
+
+    /* Avoid regular dsentries for non-relocatable regions (e.g., DMA buffers).
+     */
+    buf = _magic_real_mmap(buf, len, prot, flags, fd, offset);
+    if(buf == MAP_FAILED)
+        return buf;
+    r = sef_llvm_add_special_mem_region(buf, len, NULL);
+    if(r < 0)
+        printf("sef_llvm_add_special_mem_region failed: %d\n", r);
+    return buf;
+}
+
+/*===========================================================================*
+ *                             sef_llvm_ac_munmap                           *
+ *===========================================================================*/
+int sef_llvm_ac_munmap(void *buf, size_t len)
+{
+    int r;
+    extern int __attribute__((weak)) _magic_real_munmap(void*, size_t);
+    if (!_magic_real_munmap)
+        return munmap(buf, len);
+
+    if ((r = _magic_real_munmap(buf, len)) != 0)
+        return r;
+    if ((r = sef_llvm_del_special_mem_region_by_addr(buf)) < 0)
+        printf("sef_llvm_del_special_mem_region_by_addr failed: %d\n", r);
+    return 0;
+}
+
 /*===========================================================================*
  *                          sef_llvm_ltckpt_enabled                         *
  *===========================================================================*/