buflib: add a common dummy callbacks struct & use it

There are various allocations that can't be moved or shrunk.
Provide a global callback struct for this use case instead of
making each caller declare its own dummy struct.

Also fixed ROLO and x1000 installer code which incorrectly
used movable allocations.

Change-Id: I00088396b9826e02e69a4a33477fe1a7816374f1

6 files changed, 18 insertions, 9 deletions

diff --git a/firmware/buflib.c b/firmware/buflib.c
index 0e90e7fe72..c6ec011653 100644
--- a/firmware/buflib.c
+++ b/firmware/buflib.c
@@ -97,6 +97,12 @@
 
 #define BPANICF panicf
 
+struct buflib_callbacks buflib_ops_locked = {
+    .move_callback = NULL,
+    .shrink_callback = NULL,
+    .sync_callback = NULL,
+};
+
 #define IS_MOVABLE(a) (!a[2].ops || a[2].ops->move_callback)
 static union buflib_data* find_first_free(struct buflib_context *ctx);
 static union buflib_data* find_block_before(struct buflib_context *ctx,
diff --git a/firmware/common/zip.c b/firmware/common/zip.c
index 9512d6c239..36b90a9223 100644
--- a/firmware/common/zip.c
+++ b/firmware/common/zip.c
@@ -32,9 +32,7 @@
 #include "crc32.h"
 #include "rbendian.h"
 
-#define zip_core_alloc(N) core_alloc_ex("zip",(N),&dummy_ops)
-
-static struct buflib_callbacks dummy_ops;
+#define zip_core_alloc(N) core_alloc_ex("zip",(N),&buflib_ops_locked)
 
 enum {
     ZIP_SIG_ED = 0x06054b50,
diff --git a/firmware/include/buflib.h b/firmware/include/buflib.h
index 7f534c6ce0..e805ebbf1b 100644
--- a/firmware/include/buflib.h
+++ b/firmware/include/buflib.h
@@ -129,6 +129,12 @@ struct buflib_callbacks {
     void (*sync_callback)(int handle, bool sync_on);
 };
 
+/** A set of all NULL callbacks for use with allocations that need to stay
+ * locked in RAM and not moved or shrunk. These type of allocations should
+ * be avoided as much as possible to avoid memory fragmentation but it can
+ * suitable for short-lived allocations. */
+extern struct buflib_callbacks buflib_ops_locked;
+
 #define BUFLIB_SHRINK_SIZE_MASK (~BUFLIB_SHRINK_POS_MASK)
 #define BUFLIB_SHRINK_POS_FRONT (1u<<31)
 #define BUFLIB_SHRINK_POS_BACK  (1u<<30)
diff --git a/firmware/rolo.c b/firmware/rolo.c
index 5f936c95f4..f95fc4bd4d 100644
--- a/firmware/rolo.c
+++ b/firmware/rolo.c
@@ -242,7 +242,7 @@ int rolo_load(const char* filename)
 
     /* get the system buffer. release only in case of error, otherwise
      * we don't return anyway */
-    rolo_handle = core_alloc_maximum("rolo", &filebuf_size, NULL);
+    rolo_handle = core_alloc_maximum("rolo", &filebuf_size, &buflib_ops_locked);
     if (rolo_handle < 0)
     {
         rolo_error("OOM");
diff --git a/firmware/target/mips/ingenic_x1000/installer-x1000.c b/firmware/target/mips/ingenic_x1000/installer-x1000.c
index 0a09ad0e91..66aa42d4a1 100644
--- a/firmware/target/mips/ingenic_x1000/installer-x1000.c
+++ b/firmware/target/mips/ingenic_x1000/installer-x1000.c
@@ -148,7 +148,7 @@ static int updater_init(struct updater* u)
 
     /* buf_len is a bit oversized here, but it's not really important */
     u->buf_len = u->img_len + sizeof(mtar_t) + 2*CACHEALIGN_SIZE;
-    u->buf_hnd = core_alloc("boot_image", u->buf_len);
+    u->buf_hnd = core_alloc_ex("boot_image", u->buf_len, &buflib_ops_locked);
     if(u->buf_hnd < 0) {
         rc = IERR_OUT_OF_MEMORY;
         goto error;
diff --git a/firmware/usbstack/usb_storage.c b/firmware/usbstack/usb_storage.c
index a32cf185e7..eb82f72eae 100644
--- a/firmware/usbstack/usb_storage.c
+++ b/firmware/usbstack/usb_storage.c
@@ -449,12 +449,11 @@ void usb_storage_init_connection(void)
 #endif
 #else
     unsigned char * buffer;
-    /* dummy ops with no callbacks, needed because by
-     * default buflib buffers can be moved around which must be avoided */
-    static struct buflib_callbacks dummy_ops;
 
     // Add 31 to handle worst-case misalignment
-    usb_handle = core_alloc_ex("usb storage", ALLOCATE_BUFFER_SIZE + MAX_CBW_SIZE + 31, &dummy_ops);
+    usb_handle = core_alloc_ex("usb storage",
+                               ALLOCATE_BUFFER_SIZE + MAX_CBW_SIZE + 31,
+                               &buflib_ops_locked);
     if (usb_handle < 0)
         panicf("%s(): OOM", __func__);