SYSLINK: ipc - reference count for shared regionsti-2.6.31-omap4-L24.3-p2

Added reference counts for each shared region entry.  This way, if the same
region is added and deleted multiple times, it will go through safely (and
not be deleted after the first time).

Signed-off-by: Simon Que <sque@ti.com>

1 files changed, 28 insertions, 3 deletions

diff --git a/drivers/dsp/syslink/multicore_ipc/sharedregion.c b/drivers/dsp/syslink/multicore_ipc/sharedregion.c
index c5ad146d4da7..cfcd1aa1ee53 100755
--- a/drivers/dsp/syslink/multicore_ipc/sharedregion.c
+++ b/drivers/dsp/syslink/multicore_ipc/sharedregion.c
@@ -41,6 +41,8 @@ struct sharedregion_module_object {
 	u32 bitOffset;  /* Index bit offset */
 	u32 region_size; /* Max size of each region */
 	struct sharedregion_config cfg;	/* Current config values */
+	u32 *ref_count_table; /* The number of times each
+							entry has been added */
 };
 
 /*
@@ -138,6 +140,14 @@ int sharedregion_setup(const struct sharedregion_config *config)
 		goto table_alloc_fail;
 	}
 
+	sharedregion_state.ref_count_table = kmalloc(sizeof(u32) *
+					tmpcfg->max_regions * (proc_count + 1),
+					GFP_KERNEL);
+	if (sharedregion_state.ref_count_table == NULL) {
+		retval = -ENOMEM;
+		goto table_alloc_fail;
+	}
+
 	table = sharedregion_state.table;
 	for (i = 0; i < tmpcfg->max_regions; i++) {
 		for (j = 0; j < (proc_count + 1); j++) {
@@ -145,6 +155,8 @@ int sharedregion_setup(const struct sharedregion_config *config)
 									false;
 			(table + (j * tmpcfg->max_regions) + i)->base = 0;
 			(table + (j * tmpcfg->max_regions) + i)->len = 0;
+			sharedregion_state.ref_count_table[(j *
+						tmpcfg->max_regions) + i] = 0;
 		}
 	}
 
@@ -192,6 +204,7 @@ int sharedregion_destroy(void)
 	if (retval)
 		goto error;
 
+	kfree(sharedregion_state.ref_count_table);
 	kfree(sharedregion_state.table);
 	gate_handle = sharedregion_state.gate_handle; /* backup gate handle */
 	memset(&sharedregion_state, 0,
@@ -293,6 +306,9 @@ int sharedregion_add(u32 index, void *base, u32 len)
 
 	} else {
 		/* FHACK: FIX ME */
+		sharedregion_state.ref_count_table[(myproc_id *
+				sharedregion_state.cfg.max_regions)
+				+ index] += 1;
 		retval = 1;
 		goto dup_entry_error;
 	}
@@ -348,9 +364,18 @@ int sharedregion_remove(u32 index)
 	entry = (table
 		 + (myproc_id * sharedregion_state.cfg.max_regions)
 		 + index);
-	entry->is_valid = false;
-	entry->base = NULL;
-	entry->len = 0;
+
+	if (sharedregion_state.ref_count_table[(myproc_id *
+				sharedregion_state.cfg.max_regions)
+				+ index] > 0)
+		sharedregion_state.ref_count_table[(myproc_id *
+				sharedregion_state.cfg.max_regions)
+				+ index] -= 1;
+	else {
+		entry->is_valid = false;
+		entry->base = NULL;
+		entry->len = 0;
+	}
 	mutex_unlock(sharedregion_state.gate_handle);
 	return 0;