3 files changed, 38 insertions, 67 deletions

diff --git a/firmware/common/dircache.c b/firmware/common/dircache.c
index 8917b3348e..1d6371a6b5 100644
--- a/firmware/common/dircache.c
+++ b/firmware/common/dircache.c
@@ -249,7 +249,6 @@ static struct dircache_runinfo
     /* cache buffer info */
     int          handle;           /* buflib buffer handle */
     size_t       bufsize;          /* size of buflib allocation - 1 */
-    int          buflocked;        /* don't move due to other allocs */
     union {
     void                  *p;      /* address of buffer - ENTRYSIZE */
     struct dircache_entry *pentry; /* alias of .p to assist entry resolution */
@@ -329,29 +328,9 @@ static inline void dumpster_clean_buffer(void *p, size_t size)
  */
 static int move_callback(int handle, void *current, void *new)
 {
-    if (dircache_runinfo.buflocked)
-        return BUFLIB_CB_CANNOT_MOVE;
-
+    (void)handle; (void)current;
     dircache_runinfo.p = new - ENTRYSIZE;
-
     return BUFLIB_CB_OK;
-    (void)handle; (void)current;
-}
-
-/**
- * add a "don't move" lock count
- */
-static inline void buffer_lock(void)
-{
-    dircache_runinfo.buflocked++;
-}
-
-/**
- * remove a "don't move" lock count
- */
-static inline void buffer_unlock(void)
-{
-    dircache_runinfo.buflocked--;
 }
 
 
@@ -530,14 +509,14 @@ static void set_buffer(int handle, size_t size)
 
 /**
  * remove the allocation from dircache control and return the handle
+ * Note that dircache must not be using the buffer!
  */
 static int reset_buffer(void)
 {
     int handle = dircache_runinfo.handle;
     if (handle > 0)
     {
-        /* don't mind .p; it might get changed by the callback even after
-           this call; buffer presence is determined by the following: */
+        /* don't mind .p; buffer presence is determined by the following: */
         dircache_runinfo.handle  = 0;
         dircache_runinfo.bufsize = 0;
     }
@@ -1857,7 +1836,7 @@ static void reset_cache(void)
  */
 static void build_volumes(void)
 {
-    buffer_lock();
+    core_pin(dircache_runinfo.handle);
 
     for (int i = 0; i < NUM_VOLUMES; i++)
     {
@@ -1903,12 +1882,14 @@ static void build_volumes(void)
 
     logf("Done, %ld KiB used", dircache.size / 1024);
 
-    buffer_unlock();
+    core_unpin(dircache_runinfo.handle);
 }
 
 /**
  * allocate buffer and return whether or not a synchronous build should take
  * place; if 'realloced' is NULL, it's just a query about what will happen
+ *
+ * Note this must be called with the dircache_lock() active.
  */
 static int prepare_build(bool *realloced)
 {
@@ -1958,16 +1939,14 @@ static int prepare_build(bool *realloced)
     *realloced = true;
     reset_cache();
 
-    buffer_lock();
-
     int handle = reset_buffer();
-    dircache_unlock();
+    dircache_unlock(); /* release lock held by caller */
 
     core_free(handle);
 
     handle = alloc_cache(size);
 
-    dircache_lock();
+    dircache_lock(); /* reacquire lock */
 
     if (dircache_runinfo.suspended && handle > 0)
     {
@@ -1979,13 +1958,9 @@ static int prepare_build(bool *realloced)
     }
 
     if (handle <= 0)
-    {
-        buffer_unlock();
         return -1;
-    }
 
     set_buffer(handle, size);
-    buffer_unlock();
 
     return syncbuild;
 }
@@ -2384,9 +2359,9 @@ void dircache_fileop_create(struct file_base_info *dirinfop,
     if ((dinp->attr & ATTR_DIRECTORY) && !is_dotdir_name(basename))
     {
         /* scan-in the contents of the new directory at this level only */
-        buffer_lock();
+        core_pin(dircache_runinfo.handle);
         sab_process_dir(infop, false);
-        buffer_unlock();
+        core_unpin(dircache_runinfo.handle);
     }
 }
 
@@ -2915,7 +2890,7 @@ void dircache_dump(void)
 
     if (dircache_runinfo.handle)
     {
-        buffer_lock();
+        core_pin(dircache_runinfo.handle);
 
         /* bin */
         write(fdbin, dircache_runinfo.p + ENTRYSIZE,
@@ -2985,7 +2960,7 @@ void dircache_dump(void)
                      tm.tm_hour, tm.tm_min, tm.tm_sec);
         }
 
-        buffer_unlock();
+        core_unpin(dircache_runinfo.handle);
     }
 
     dircache_unlock();
@@ -3104,7 +3079,6 @@ int dircache_load(void)
     }
 
     dircache_lock();
-    buffer_lock();
 
     if (!dircache_is_clean(false))
         goto error;
@@ -3113,6 +3087,7 @@ int dircache_load(void)
     dircache = maindata.dircache;
 
     set_buffer(handle, bufsize);
+    core_pin(handle);
     hasbuffer = true;
 
     /* convert back to in-RAM representation */
@@ -3167,13 +3142,13 @@ int dircache_load(void)
     dircache_enable_internal(false);
 
     /* cache successfully loaded */
+    core_unpin(handle);
     logf("Done, %ld KiB used", dircache.size / 1024);
     rc = 0;
 error:
     if (rc < 0 && hasbuffer)
         reset_buffer();
 
-    buffer_unlock();
     dircache_unlock();
 
 error_nolock:
@@ -3199,8 +3174,9 @@ int dircache_save(void)
     if (fd < 0)
         return -1;
 
+    /* it seems the handle *must* exist if this function is called */
     dircache_lock();
-    buffer_lock();
+    core_pin(dircache_runinfo.handle);
 
     int rc = -1;
 
@@ -3269,7 +3245,7 @@ int dircache_save(void)
        that makes what was saved completely invalid */
     rc = 0;
 error:
-    buffer_unlock();
+    core_unpin(dircache_runinfo.handle);
     dircache_unlock();
 
     if (rc < 0)
diff --git a/firmware/common/unicode.c b/firmware/common/unicode.c
index f0f663f712..e53ad6bcb0 100644
--- a/firmware/common/unicode.c
+++ b/firmware/common/unicode.c
@@ -168,6 +168,10 @@ static unsigned short default_cp_table_buf[MAX_CP_TABLE_SIZE+1];
     do {} while (0)
 #define cp_table_alloc(filename, size, opsp) \
     ({ (void)(opsp); 1; })
+#define cp_table_pin(handle) \
+    do { (void)handle; } while(0)
+#define cp_table_unpin(handle) \
+    do { (void)handle; } while(0)
 #else
 #define cp_table_alloc(filename, size, opsp) \
     core_alloc_ex((filename), (size), (opsp))
@@ -175,6 +179,10 @@ static unsigned short default_cp_table_buf[MAX_CP_TABLE_SIZE+1];
     core_free(handle)
 #define cp_table_get_data(handle) \
     core_get_data(handle)
+#define cp_table_pin(handle) \
+    core_pin(handle)
+#define cp_table_unpin(handle) \
+    core_unpin(handle)
 #endif
 
 static const unsigned char utf8comp[6] =
@@ -191,21 +199,8 @@ static inline void cptable_tohw16(uint16_t *buf, unsigned int count)
     (void)buf; (void)count;
 }
 
-static int move_callback(int handle, void *current, void *new)
-{
-    /* we don't keep a pointer but we have to stop it if this applies to a
-       buffer not yet swapped-in since it will likely be in use in an I/O
-       call */
-    return (handle != default_cp_handle || default_cp_table_ref != 0) ?
-                BUFLIB_CB_CANNOT_MOVE : BUFLIB_CB_OK;
-    (void)current; (void)new;
-}
-
 static int alloc_and_load_cp_table(int cp, void *buf)
 {
-    static struct buflib_callbacks ops =
-        { .move_callback = move_callback };
-
     /* alloc and read only if there is an associated file */
     const char *filename = cp_info[cp].filename;
     if (!filename)
@@ -228,13 +223,17 @@ static int alloc_and_load_cp_table(int cp, void *buf)
         !(size % (off_t)sizeof (uint16_t))) {
 
         /* if the buffer is provided, use that but don't alloc */
-        int handle = buf ? 0 : cp_table_alloc(filename, size, &ops);
-        if (handle > 0)
+        int handle = buf ? 0 : cp_table_alloc(filename, size, NULL);
+        if (handle > 0) {
+            cp_table_pin(handle);
             buf = cp_table_get_data(handle);
+        }
 
         if (buf && read(fd, buf, size) == size) {
             close(fd);
             cptable_tohw16(buf, size / sizeof (uint16_t));
+            if (handle > 0)
+                cp_table_unpin(handle);
             return handle;
         }
 
diff --git a/firmware/font.c b/firmware/font.c
index 724cb84d57..7ce64ed47d 100644
--- a/firmware/font.c
+++ b/firmware/font.c
@@ -90,7 +90,6 @@ extern struct font sysfont;
 
 struct buflib_alloc_data {
     struct font font;    /* must be the first member! */
-    int handle_locks;    /* is the buflib handle currently locked? */
     int refcount;        /* how many times has this font been loaded? */
     unsigned char buffer[];
 };
@@ -107,9 +106,6 @@ static int buflibmove_callback(int handle, void* current, void* new)
     struct buflib_alloc_data *alloc = (struct buflib_alloc_data*)current;
     ptrdiff_t diff = new - current;
 
-    if (alloc->handle_locks > 0)
-        return BUFLIB_CB_CANNOT_MOVE;
-
 #define UPDATE(x) if (x) { x = PTR_ADD(x, diff); }
 
     UPDATE(alloc->font.bits);
@@ -129,18 +125,18 @@ static void lock_font_handle(int handle, bool lock)
 {
     if ( handle < 0 )
         return;
-    struct buflib_alloc_data *alloc = core_get_data(handle);
-    if ( lock )
-        alloc->handle_locks++;
+
+    if (lock)
+        core_pin(handle);
     else
-        alloc->handle_locks--;
+        core_unpin(handle);
 }
 
 void font_lock(int font_id, bool lock)
 {
     if( font_id < 0 || font_id >= MAXFONTS )
         return;
-    if( buflib_allocations[font_id] >= 0 )
+    if( buflib_allocations[font_id] > 0 )
         lock_font_handle(buflib_allocations[font_id], lock);
 }
 
@@ -522,8 +518,8 @@ int font_load_ex( const char *path, size_t buf_size, int glyphs )
         return -1;
     }
     struct buflib_alloc_data *pdata;
+    core_pin(handle);
     pdata = core_get_data(handle);
-    pdata->handle_locks = 1;
     pdata->refcount     = 1;
 
     /* load and init */