Change from ibv_get_devices() to ibv_get_device_list()

Change libibverbs API for listing all known devices from
ibv_get_devices() to ibv_get_device_list(), and update all in-tree
uses of this API.

Signed-off-by: Roland Dreier <rolandd@cisco.com>

13 files changed, 176 insertions, 132 deletions

diff --git a/ChangeLog b/ChangeLog
index b167835..4a069e1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,4 +1,15 @@
-2005-11-10  Sean Hefty <sean.hefty@intel.com>
+2005-11-11  Roland Dreier  <roland@cisco.com>
+
+	* examples/asyncwatch.c, examples/rc_pingpong.c,
+	examples/srq_pingpong.c, examples/uc_pingpong.c,
+	examples/ud_pingpong.c, examples/device_list.c,
+	examples/devinfo.c: Update examples to match new API.
+	
+	* include/infiniband/verbs.h, src/device.c, src/init.c,
+	src/ibverbs.h: Change from dlist-based ibv_get_devices() API to
+	simpler ibv_get_device_list() and ibv_free_device_list() API.
+
+2005-11-10  Sean Hefty  <sean.hefty@intel.com>
 
 	* include/infiniband/sa-kern-abi.h: New include file to contain
 	definitions of SA structures passed between userspace and kernel.
diff --git a/examples/asyncwatch.c b/examples/asyncwatch.c
index d4943ca..734d018 100644
--- a/examples/asyncwatch.c
+++ b/examples/asyncwatch.c
@@ -50,34 +50,30 @@ static inline uint64_t be64_to_cpu(uint64_t x) { return x; }
 
 int main(int argc, char *argv[])
 {
-	struct dlist *dev_list;
-	struct ibv_device *ib_dev;
+	struct ibv_device **dev_list;
 	struct ibv_context *context;
 	struct ibv_async_event event;
 
-	dev_list = ibv_get_devices();
+	dev_list = ibv_get_device_list(NULL);
 	if (!dev_list) {
 		fprintf(stderr, "No IB devices found\n");
 		return 1;
 	}
 
-	dlist_start(dev_list);
-	ib_dev = dlist_next(dev_list);
-
-	if (!ib_dev) {
+	if (!*dev_list) {
 		fprintf(stderr, "No IB devices found\n");
 		return 1;
 	}
 
-	context = ibv_open_device(ib_dev);
+	context = ibv_open_device(*dev_list);
 	if (!context) {
 		fprintf(stderr, "Couldn't get context for %s\n",
-			ibv_get_device_name(ib_dev));
+			ibv_get_device_name(*dev_list));
 		return 1;
 	}
 
 	printf("%s: async event FD %d\n",
-	       ibv_get_device_name(ib_dev), context->async_fd);
+	       ibv_get_device_name(*dev_list), context->async_fd);
 
 	while (1) {
 		if (ibv_get_async_event(context, &event))
diff --git a/examples/device_list.c b/examples/device_list.c
index 37f3a40..f04fba4 100644
--- a/examples/device_list.c
+++ b/examples/device_list.c
@@ -51,10 +51,9 @@ static inline uint64_t be64_to_cpu(uint64_t x) { return x; }
 
 int main(int argc, char *argv[])
 {
-	struct dlist *dev_list;
-	struct ibv_device *ib_dev;
+	struct ibv_device **dev_list;
 
-	dev_list = ibv_get_devices();
+	dev_list = ibv_get_device_list(NULL);
 	if (!dev_list) {
 		fprintf(stderr, "No IB devices found\n");
 		return 1;
@@ -63,10 +62,12 @@ int main(int argc, char *argv[])
 	printf("    %-16s\t   node GUID\n", "device");
 	printf("    %-16s\t----------------\n", "------");
 
-	dlist_for_each_data(dev_list, ib_dev, struct ibv_device)
+	while (*dev_list) {
 		printf("    %-16s\t%016llx\n",
-		       ibv_get_device_name(ib_dev),
-		       (unsigned long long) be64_to_cpu(ibv_get_device_guid(ib_dev)));
+		       ibv_get_device_name(*dev_list),
+		       (unsigned long long) be64_to_cpu(ibv_get_device_guid(*dev_list)));
+		++dev_list;
+	}
 
 	return 0;
 }
diff --git a/examples/devinfo.c b/examples/devinfo.c
index 7ad5dad..0e3e020 100644
--- a/examples/devinfo.c
+++ b/examples/devinfo.c
@@ -299,11 +299,11 @@ cleanup:
 
 static void usage(const char *argv0)
 {
-        printf("Usage: %s             print the ca attributes\n", argv0);
-        printf("\n");
-        printf("Options:\n");
-        printf("  -d, --ib-dev=<dev>     use IB device <dev> (default first device found)\n");
-        printf("  -i, --ib-port=<port>   use port <port> of IB device (default all ports)\n");
+	printf("Usage: %s             print the ca attributes\n", argv0);
+	printf("\n");
+	printf("Options:\n");
+	printf("  -d, --ib-dev=<dev>     use IB device <dev> (default first device found)\n");
+	printf("  -i, --ib-port=<port>   use port <port> of IB device (default all ports)\n");
 	printf("  -l, --list             print only the IB devices names\n");
 	printf("  -v, --verbose          print all the attributes of the IB device(s)\n");
 }
@@ -312,60 +312,56 @@ int main(int argc, char *argv[])
 {
 	char *ib_devname = NULL;
 	int ret = 0;
-	struct dlist *dev_list;
-	struct ibv_device *ib_dev;
+	struct ibv_device **dev_list;
 	int num_of_hcas;
 	int ib_port = 0;
 
 	/* parse command line options */
 	while (1) {
 	        int c;
-                static struct option long_options[] = {
-                        { .name = "ib-dev",   .has_arg = 1, .val = 'd' },
-                        { .name = "ib-port",  .has_arg = 1, .val = 'i' },
+		static struct option long_options[] = {
+			{ .name = "ib-dev",   .has_arg = 1, .val = 'd' },
+			{ .name = "ib-port",  .has_arg = 1, .val = 'i' },
 			{ .name = "list",     .has_arg = 0, .val = 'l' },
-                        { .name = "verbose",  .has_arg = 0, .val = 'v' },
-                        { 0, 0, 0, 0}
-                };
+			{ .name = "verbose",  .has_arg = 0, .val = 'v' },
+			{ 0, 0, 0, 0}
+		};
 		
-                c = getopt_long(argc, argv, "d:i:lv", long_options, NULL);
-                if (c == -1)
-                        break;
-
-                switch (c) {
-                case 'd':
-                        ib_devname = strdup(optarg);
-                        break;
-
-                case 'i':
-                        ib_port = strtol(optarg, NULL, 0);
-                        if (ib_port < 0) {
-                                usage(argv[0]);
-                                return 1;
-                        }
-                        break;
+		c = getopt_long(argc, argv, "d:i:lv", long_options, NULL);
+		if (c == -1)
+			break;
+
+		switch (c) {
+		case 'd':
+			ib_devname = strdup(optarg);
+			break;
+
+		case 'i':
+			ib_port = strtol(optarg, NULL, 0);
+			if (ib_port < 0) {
+				usage(argv[0]);
+				return 1;
+			}
+			break;
 
 		case 'v':
-                        verbose = 1;
-                        break;
+			verbose = 1;
+			break;
 
 		case 'l':
-			dev_list = ibv_get_devices();
+			dev_list = ibv_get_device_list(&num_of_hcas);
 			if (!dev_list) {
 				fprintf(stderr, "Failed to get IB devices list");
 				return -1;
 			}
 
-		        num_of_hcas = 0;
-              		dlist_for_each_data(dev_list, ib_dev, struct ibv_device)
-                    		num_of_hcas ++;
-
 			printf("%d HCA%s found:\n", num_of_hcas,
 			       num_of_hcas != 1 ? "s" : "");
 
-			dlist_start(dev_list);
-			dlist_for_each_data(dev_list, ib_dev, struct ibv_device)
-				printf("\t%s\n", ibv_get_device_name(ib_dev));
+			while (*dev_list) {
+				printf("\t%s\n", ibv_get_device_name(*dev_list));
+				++dev_list;
+			}
 
 			printf("\n");
 			return 0;
@@ -376,28 +372,31 @@ int main(int argc, char *argv[])
 		}
 	}
 
-	dev_list = ibv_get_devices();
+	dev_list = ibv_get_device_list(NULL);
 	if (!dev_list) {
 		fprintf(stderr, "Failed to get IB device list\n");
 		return -1;
 	}
-	dlist_start(dev_list);
+
 	if (ib_devname) {
-		dlist_for_each_data(dev_list, ib_dev, struct ibv_device)
-			if (!strcmp(ibv_get_device_name(ib_dev), ib_devname))
+		while (*dev_list) {
+			if (!strcmp(ibv_get_device_name(*dev_list), ib_devname))
 				break;
-		if (!ib_dev) {
+			++dev_list;
+		}
+
+		if (!*dev_list) {
 			fprintf(stderr, "IB device '%s' wasn't found\n", ib_devname);
 			return -1;
 		}
-		ret |= print_hca_cap(ib_dev, ib_port);
+
+		ret |= print_hca_cap(*dev_list, ib_port);
 	} else {
-                ib_dev = dlist_next(dev_list);
-                if (!ib_dev) {
-                        fprintf(stderr, "No IB devices found\n");
-                        return -1;
-                }
-		ret |= print_hca_cap(ib_dev, ib_port);
+		if (!*dev_list) {
+			fprintf(stderr, "No IB devices found\n");
+			return -1;
+		}
+		ret |= print_hca_cap(*dev_list, ib_port);
 	}
 
 	if (ib_devname)
diff --git a/examples/rc_pingpong.c b/examples/rc_pingpong.c
index 947ae54..7c5e448 100644
--- a/examples/rc_pingpong.c
+++ b/examples/rc_pingpong.c
@@ -447,7 +447,7 @@ static void usage(const char *argv0)
 
 int main(int argc, char *argv[])
 {
-	struct dlist 	  	*dev_list;
+	struct ibv_device      **dev_list;
 	struct ibv_device 	*ib_dev;
 	struct pingpong_context *ctx;
 	struct pingpong_dest     my_dest;
@@ -536,21 +536,20 @@ int main(int argc, char *argv[])
 
 	page_size = sysconf(_SC_PAGESIZE);
 
-	dev_list = ibv_get_devices();
+	dev_list = ibv_get_device_list(NULL);
 	if (!dev_list) {
 		fprintf(stderr, "No IB devices found\n");
 		return 1;
 	}
 
-	dlist_start(dev_list);
 	if (!ib_devname) {
-		ib_dev = dlist_next(dev_list);
+		ib_dev = *dev_list;
 		if (!ib_dev) {
 			fprintf(stderr, "No IB devices found\n");
 			return 1;
 		}
 	} else {
-		dlist_for_each_data(dev_list, ib_dev, struct ibv_device)
+		for (ib_dev = *dev_list; ib_dev; ++dev_list)
 			if (!strcmp(ibv_get_device_name(ib_dev), ib_devname))
 				break;
 		if (!ib_dev) {
diff --git a/examples/srq_pingpong.c b/examples/srq_pingpong.c
index f922be9..8a68dd7 100644
--- a/examples/srq_pingpong.c
+++ b/examples/srq_pingpong.c
@@ -509,7 +509,7 @@ static void usage(const char *argv0)
 
 int main(int argc, char *argv[])
 {
-	struct dlist 	  	*dev_list;
+	struct ibv_device      **dev_list;
 	struct ibv_device 	*ib_dev;
 	struct pingpong_context *ctx;
 	struct pingpong_dest     my_dest[MAX_QP];
@@ -605,21 +605,20 @@ int main(int argc, char *argv[])
 
 	page_size = sysconf(_SC_PAGESIZE);
 
-	dev_list = ibv_get_devices();
+	dev_list = ibv_get_device_list(NULL);
 	if (!dev_list) {
 		fprintf(stderr, "No IB devices found\n");
 		return 1;
 	}
 
-	dlist_start(dev_list);
 	if (!ib_devname) {
-		ib_dev = dlist_next(dev_list);
+		ib_dev = *dev_list;
 		if (!ib_dev) {
 			fprintf(stderr, "No IB devices found\n");
 			return 1;
 		}
 	} else {
-		dlist_for_each_data(dev_list, ib_dev, struct ibv_device)
+		for (ib_dev = *dev_list; ib_dev; ++dev_list)
 			if (!strcmp(ibv_get_device_name(ib_dev), ib_devname))
 				break;
 		if (!ib_dev) {
diff --git a/examples/uc_pingpong.c b/examples/uc_pingpong.c
index a18cc4f..fdaa3cb 100644
--- a/examples/uc_pingpong.c
+++ b/examples/uc_pingpong.c
@@ -435,7 +435,7 @@ static void usage(const char *argv0)
 
 int main(int argc, char *argv[])
 {
-	struct dlist 	  	*dev_list;
+	struct ibv_device      **dev_list;
 	struct ibv_device 	*ib_dev;
 	struct pingpong_context *ctx;
 	struct pingpong_dest     my_dest;
@@ -524,21 +524,20 @@ int main(int argc, char *argv[])
 
 	page_size = sysconf(_SC_PAGESIZE);
 
-	dev_list = ibv_get_devices();
+	dev_list = ibv_get_device_list(NULL);
 	if (!dev_list) {
 		fprintf(stderr, "No IB devices found\n");
 		return 1;
 	}
 
-	dlist_start(dev_list);
 	if (!ib_devname) {
-		ib_dev = dlist_next(dev_list);
+		ib_dev = *dev_list;
 		if (!ib_dev) {
 			fprintf(stderr, "No IB devices found\n");
 			return 1;
 		}
 	} else {
-		dlist_for_each_data(dev_list, ib_dev, struct ibv_device)
+		for (ib_dev = *dev_list; ib_dev; ++dev_list)
 			if (!strcmp(ibv_get_device_name(ib_dev), ib_devname))
 				break;
 		if (!ib_dev) {
diff --git a/examples/ud_pingpong.c b/examples/ud_pingpong.c
index 4fcf854..0ddd839 100644
--- a/examples/ud_pingpong.c
+++ b/examples/ud_pingpong.c
@@ -443,7 +443,7 @@ static void usage(const char *argv0)
 
 int main(int argc, char *argv[])
 {
-	struct dlist 	  	*dev_list;
+	struct ibv_device      **dev_list;
 	struct ibv_device 	*ib_dev;
 	struct pingpong_context *ctx;
 	struct pingpong_dest     my_dest;
@@ -532,21 +532,20 @@ int main(int argc, char *argv[])
 
 	page_size = sysconf(_SC_PAGESIZE);
 
-	dev_list = ibv_get_devices();
+	dev_list = ibv_get_device_list(NULL);
 	if (!dev_list) {
 		fprintf(stderr, "No IB devices found\n");
 		return 1;
 	}
 
-	dlist_start(dev_list);
 	if (!ib_devname) {
-		ib_dev = dlist_next(dev_list);
+		ib_dev = *dev_list;
 		if (!ib_dev) {
 			fprintf(stderr, "No IB devices found\n");
 			return 1;
 		}
 	} else {
-		dlist_for_each_data(dev_list, ib_dev, struct ibv_device)
+		for (ib_dev = *dev_list; ib_dev; ++dev_list)
 			if (!strcmp(ibv_get_device_name(ib_dev), ib_devname))
 				break;
 		if (!ib_dev) {
diff --git a/include/infiniband/verbs.h b/include/infiniband/verbs.h
index e88043c..cd86b2a 100644
--- a/include/infiniband/verbs.h
+++ b/include/infiniband/verbs.h
@@ -585,9 +585,21 @@ struct ibv_context {
 };
 
 /**
- * ibv_get_devices - Return list of IB devices
+ * ibv_get_device_list - Get list of IB devices currently available
+ * @num_devices: optional.  if non-NULL, set to the number of devices
+ * returned in the array.
+ *
+ * Return a NULL-terminated array of IB devices.  The array can be
+ * released with ibv_free_device_list().
+ */
+extern struct ibv_device **ibv_get_device_list(int *num_devices);
+
+/**
+ * ibv_free_device_list - Free list from ibv_get_device_list()
+ *
+ * Free an array of devices returned from ibv_get_device_list()
  */
-extern struct dlist *ibv_get_devices(void);
+extern void ibv_free_device_list(struct ibv_device **list);
 
 /**
  * ibv_get_device_name - Return kernel device name
diff --git a/src/device.c b/src/device.c
index c425b06..e31b4b7 100644
--- a/src/device.c
+++ b/src/device.c
@@ -49,21 +49,36 @@
 #include "ibverbs.h"
 
 static pthread_mutex_t device_list_lock = PTHREAD_MUTEX_INITIALIZER;
-static struct dlist *device_list;
+static int num_devices;
+static struct ibv_device **device_list;
 
-struct dlist *ibv_get_devices(void)
+struct ibv_device **ibv_get_device_list(int *num)
 {
-	struct dlist *l;
+	struct ibv_device **l;
+	int i;
 
 	pthread_mutex_lock(&device_list_lock);
-	if (!device_list)
-		device_list = ibverbs_init();
-	l = device_list;
+
+	if (!num_devices)
+		num_devices = ibverbs_init(&device_list);
+
+	l = calloc(num_devices, sizeof (struct ibv_device *));
+	for (i = 0; i < num_devices; ++i)
+		l[i] = device_list[i];
+
 	pthread_mutex_unlock(&device_list_lock);
 
+	if (num)
+		*num = l ? num_devices : 0;
+
 	return l;
 }
 
+void ibv_free_device_list(struct ibv_device **list)
+{
+	free(list);
+}
+
 const char *ibv_get_device_name(struct ibv_device *device)
 {
 	return device->ibdev->name;
diff --git a/src/ibverbs.h b/src/ibverbs.h
index 96a88b3..2849da7 100644
--- a/src/ibverbs.h
+++ b/src/ibverbs.h
@@ -47,7 +47,8 @@
 #define PFX		"libibverbs: "
 
 struct ibv_driver {
-	ibv_driver_init_func init_func;
+	ibv_driver_init_func	init_func;
+	struct ibv_driver      *next;
 };
 
 struct ibv_abi_compat_v2 {
@@ -57,11 +58,11 @@ struct ibv_abi_compat_v2 {
 
 extern HIDDEN int abi_ver;
 
-extern struct dlist *ibverbs_init(void);
+extern HIDDEN int ibverbs_init(struct ibv_device ***list);
 
-extern int ibv_init_mem_map(void);
-extern int ibv_lock_range(void *base, size_t size);
-extern int ibv_unlock_range(void *base, size_t size);
+extern HIDDEN int ibv_init_mem_map(void);
+extern HIDDEN int ibv_lock_range(void *base, size_t size);
+extern HIDDEN int ibv_unlock_range(void *base, size_t size);
 
 #define IBV_INIT_CMD(cmd, size, opcode)					\
 	do {								\
diff --git a/src/init.c b/src/init.c
index f4d4fc0..eb5ce17 100644
--- a/src/init.c
+++ b/src/init.c
@@ -55,7 +55,7 @@ HIDDEN int abi_ver;
 static char default_path[] = DRIVER_PATH;
 static const char *user_path;
 
-static struct dlist *driver_list;
+static struct ibv_driver *driver_list;
 
 static void load_driver(char *so_path)
 {
@@ -82,7 +82,8 @@ static void load_driver(char *so_path)
 	}
 
 	driver->init_func = init_func;
-	dlist_push(driver_list, driver);
+	driver->next      = driver_list;
+	driver_list       = driver;
 }
 
 static void find_drivers(char *dir)
@@ -112,8 +113,7 @@ static void find_drivers(char *dir)
 		load_driver(so_glob.gl_pathv[i]);
 }
 
-static void init_drivers(struct sysfs_class_device *verbs_dev,
-			 struct dlist *device_list)
+static struct ibv_device *init_drivers(struct sysfs_class_device *verbs_dev)
 {
 	struct sysfs_class_device *ib_dev; 
 	struct sysfs_attribute *attr;
@@ -125,7 +125,7 @@ static void init_drivers(struct sysfs_class_device *verbs_dev,
 	if (!attr) {
 		fprintf(stderr, PFX "Warning: no ibdev class attr for %s\n",
 			verbs_dev->name);
-		return;
+		return NULL;
 	}
 
 	sscanf(attr->value, "%63s", ibdev_name);
@@ -134,19 +134,17 @@ static void init_drivers(struct sysfs_class_device *verbs_dev,
 	if (!ib_dev) {
 		fprintf(stderr, PFX "Warning: no infiniband class device %s for %s\n",
 			attr->value, verbs_dev->name);
-		return;
+		return NULL;
 	}
 
-	dlist_for_each_data(driver_list, driver, struct ibv_driver) {
+	for (driver = driver_list; driver; driver = driver->next) {
 		dev = driver->init_func(verbs_dev);
 		if (dev) {
 			dev->dev    = verbs_dev;
 			dev->ibdev  = ib_dev;
 			dev->driver = driver;
 
-			dlist_push(device_list, dev);
-
-			return;
+			return dev;
 		}
 	}
 
@@ -155,6 +153,8 @@ static void init_drivers(struct sysfs_class_device *verbs_dev,
 	if (user_path)
 		fprintf(stderr, "%s:", user_path);
 	fprintf(stderr, "%s\n", default_path);
+
+	return NULL;
 }
 
 static int check_abi_version(void)
@@ -188,28 +188,23 @@ static int check_abi_version(void)
 }
 
 
-struct dlist *ibverbs_init(void)
+HIDDEN int ibverbs_init(struct ibv_device ***list)
 {
 	char *wr_path, *dir;
 	struct sysfs_class *cls;
 	struct dlist *verbs_dev_list;
-	struct dlist *device_list;
 	struct sysfs_class_device *verbs_dev;
+	struct ibv_device *device;
+	struct ibv_device **new_list;
+	int num_devices = 0;
+	int list_size = 0;
 
-	driver_list = dlist_new(sizeof (struct ibv_driver));
-	device_list = dlist_new(sizeof (struct ibv_device));
-	if (!driver_list || !device_list) {
-		fprintf(stderr, PFX "Fatal: couldn't allocate device/driver list.\n");
-		abort();
-	}
+	*list = NULL;
 
 	if (ibv_init_mem_map())
-		return NULL;
+		return 0;
 
-	/*
-	 * Check if a driver is statically linked, and if so load it first.
-	 */
-	load_driver(NULL);
+	find_drivers(default_path);
 
 	/*
 	 * Only follow the path passed in through the calling user's
@@ -224,25 +219,42 @@ struct dlist *ibverbs_init(void)
 		}
 	}
 
-	find_drivers(default_path);
+	/*
+	 * Now check if a driver is statically linked.  Since we push
+	 * drivers onto our driver list, the last driver we find will
+	 * be the first one we try.
+	 */
+	load_driver(NULL);
 
 	cls = sysfs_open_class("infiniband_verbs");
 	if (!cls) {
 		fprintf(stderr, PFX "Fatal: couldn't open sysfs class 'infiniband_verbs'.\n");
-		return NULL;
+		return 0;
 	}
 
 	if (check_abi_version())
-		return NULL;
+		return 0;
 
 	verbs_dev_list = sysfs_get_class_devices(cls);
 	if (!verbs_dev_list) {
 		fprintf(stderr, PFX "Fatal: no infiniband class devices found.\n");
-		return NULL;
+		return 0;
 	}
 
-	dlist_for_each_data(verbs_dev_list, verbs_dev, struct sysfs_class_device)
-		init_drivers(verbs_dev, device_list);
+	dlist_for_each_data(verbs_dev_list, verbs_dev, struct sysfs_class_device) {
+		device = init_drivers(verbs_dev);
+		if (device) {
+			if (list_size <= num_devices) {
+				list_size = list_size ? list_size * 2 : 1;
+				new_list = realloc(*list, list_size * sizeof (struct ibv_device *));
+				if (!new_list)
+					goto out;
+				*list = new_list;
+			}
+			*list[num_devices++] = device;
+		}
+	}
 
-	return device_list;
+out:
+	return num_devices;
 }
diff --git a/src/libibverbs.map b/src/libibverbs.map
index 56314ed..e72b0f9 100644
--- a/src/libibverbs.map
+++ b/src/libibverbs.map
@@ -1,6 +1,7 @@
 IBVERBS_1.0 {
 	global:
-		ibv_get_devices;
+		ibv_get_device_list;
+		ibv_free_device_list;
 		ibv_get_device_name;
 		ibv_get_device_guid;
 		ibv_open_device;