app,lib: fix checking mmap return value

Some places use NULL to check for mmap failure but mmap return
MAP_FAILED in this case.

Change-Id: I4796fa52421da53c94223a9e8cc26ac04968f1d8
Signed-off-by: Pawel Wodkowski <pawelx.wodkowski@intel.com>
Reviewed-on: https://review.gerrithub.io/405648
Reviewed-by: Dariusz Stojaczyk <dariuszx.stojaczyk@intel.com>
Reviewed-by: Daniel Verkamp <daniel.verkamp@intel.com>
Reviewed-by: Shuhei Matsumoto <shuhei.matsumoto.xt@hitachi.com>
Tested-by: SPDK Automated Test System <sys_sgsw@intel.com>

app/iscsi_top/iscsi_top.cpp

@@ -93,8 +93,8 @@ print_connections(void)
 	conns_size = sizeof(*conns) * MAX_ISCSI_CONNECTIONS;
 
 	conns_ptr = mmap(NULL, conns_size, PROT_READ, MAP_SHARED, fd, 0);
-	if (conns_ptr == NULL) {
-		fprintf(stderr, "Cannot mmap shared memory\n");
+	if (conns_ptr == MAP_FAILED) {
+		fprintf(stderr, "Cannot mmap shared memory (%d)\n", errno);
 		exit(1);
 	}
 
@@ -160,7 +160,7 @@ int main(int argc, char **argv)
 
 	history_ptr = mmap(NULL, sizeof(*histories), PROT_READ, MAP_SHARED, history_fd, 0);
 	if (history_ptr == MAP_FAILED) {
-		fprintf(stderr, "Unable to mmap history shm\n");
+		fprintf(stderr, "Unable to mmap history shm (%d).\n", errno);
 		exit(1);
 	}
 

lib/env_dpdk/pci.c

@@ -480,8 +480,8 @@ spdk_pci_device_claim(const struct spdk_pci_addr *pci_addr)
 
 	dev_map = mmap(NULL, sizeof(int), PROT_READ | PROT_WRITE,
 		       MAP_SHARED, dev_fd, 0);
-	if (dev_map == NULL) {
-		fprintf(stderr, "could not mmap dev %s\n", dev_name);
+	if (dev_map == MAP_FAILED) {
+		fprintf(stderr, "could not mmap dev %s (%d)\n", dev_name, errno);
 		close(dev_fd);
 		return -1;
 	}

lib/iscsi/conn.c

@@ -60,7 +60,7 @@
 static int g_connections_per_lcore;
 static uint32_t *g_num_connections;
 
-struct spdk_iscsi_conn *g_conns_array;
+struct spdk_iscsi_conn *g_conns_array = MAP_FAILED;
 static char g_shm_name[64];
 
 static pthread_mutex_t g_conns_mutex;
@@ -118,7 +118,7 @@ spdk_find_iscsi_connection_by_id(int cid)
 
 int spdk_initialize_iscsi_conns(void)
 {
-	size_t conns_size;
+	size_t conns_size = sizeof(struct spdk_iscsi_conn) * MAX_ISCSI_CONNECTIONS;
 	int conns_array_fd, rc;
 	uint32_t i, last_core;
 
@@ -134,20 +134,21 @@ int spdk_initialize_iscsi_conns(void)
 	conns_array_fd = shm_open(g_shm_name, O_RDWR | O_CREAT, 0600);
 	if (conns_array_fd < 0) {
 		SPDK_ERRLOG("could not shm_open %s\n", g_shm_name);
-		return -1;
+		goto err;
 	}
 
-	conns_size = sizeof(struct spdk_iscsi_conn) * MAX_ISCSI_CONNECTIONS;
-
 	if (ftruncate(conns_array_fd, conns_size) != 0) {
 		SPDK_ERRLOG("could not ftruncate\n");
-		close(conns_array_fd);
-		shm_unlink(g_shm_name);
-		return -1;
+		goto err;
 	}
 	g_conns_array = mmap(0, conns_size, PROT_READ | PROT_WRITE, MAP_SHARED,
 			     conns_array_fd, 0);
 
+	if (g_conns_array == MAP_FAILED) {
+		fprintf(stderr, "could not mmap cons array file %s (%d)\n", g_shm_name, errno);
+		goto err;
+	}
+
 	memset(g_conns_array, 0, conns_size);
 
 	for (i = 0; i < MAX_ISCSI_CONNECTIONS; i++) {
@@ -159,10 +160,24 @@ int spdk_initialize_iscsi_conns(void)
 	if (!g_num_connections) {
 		SPDK_ERRLOG("Could not allocate array size=%u for g_num_connections\n",
 			    last_core + 1);
-		return -1;
+		goto err;
 	}
 
 	return 0;
+
+err:
+	if (g_conns_array != MAP_FAILED) {
+		munmap(g_conns_array, conns_size);
+		g_conns_array = MAP_FAILED;
+	}
+
+	if (conns_array_fd >= 0) {
+		close(conns_array_fd);
+		shm_unlink(g_shm_name);
+	}
+
+	pthread_mutex_destroy(&g_conns_mutex);
+	return -1;
 }
 
 static void

lib/trace/trace.c

@@ -106,7 +106,7 @@ spdk_trace_init(const char *shm_name)
 
 	g_trace_histories = mmap(NULL, sizeof(*g_trace_histories), PROT_READ | PROT_WRITE,
 				 MAP_SHARED, g_trace_fd, 0);
-	if (g_trace_histories == NULL) {
+	if (g_trace_histories == MAP_FAILED) {
 		fprintf(stderr, "could not mmap shm\n");
 		goto trace_init_err;
 	}