1 files changed, 95 insertions, 33 deletions

diff --git a/tools/hv/hv_fcopy_uio_daemon.c b/tools/hv/hv_fcopy_uio_daemon.c
index 0198321d14a2..92e8307b2a46 100644
--- a/tools/hv/hv_fcopy_uio_daemon.c
+++ b/tools/hv/hv_fcopy_uio_daemon.c
@@ -35,7 +35,10 @@
 #define WIN8_SRV_MINOR		1
 #define WIN8_SRV_VERSION	(WIN8_SRV_MAJOR << 16 | WIN8_SRV_MINOR)
 
-#define FCOPY_UIO		"/sys/bus/vmbus/devices/eb765408-105f-49b6-b4aa-c123b64d17d4/uio"
+#define FCOPY_DEVICE_PATH(subdir) \
+	"/sys/bus/vmbus/devices/eb765408-105f-49b6-b4aa-c123b64d17d4/" #subdir
+#define FCOPY_UIO_PATH          FCOPY_DEVICE_PATH(uio)
+#define FCOPY_CHANNELS_PATH     FCOPY_DEVICE_PATH(channels)
 
 #define FCOPY_VER_COUNT		1
 static const int fcopy_versions[] = {
@@ -47,9 +50,62 @@ static const int fw_versions[] = {
 	UTIL_FW_VERSION
 };
 
-#define HV_RING_SIZE		0x4000 /* 16KB ring buffer size */
+static uint32_t get_ring_buffer_size(void)
+{
+	char ring_path[PATH_MAX];
+	DIR *dir;
+	struct dirent *entry;
+	struct stat st;
+	uint32_t ring_size = 0;
+	int retry_count = 0;
+
+	/* Find the channel directory */
+	dir = opendir(FCOPY_CHANNELS_PATH);
+	if (!dir) {
+		usleep(100 * 1000); /* Avoid race with kernel, wait 100ms and retry once */
+		dir = opendir(FCOPY_CHANNELS_PATH);
+		if (!dir) {
+			syslog(LOG_ERR, "Failed to open channels directory: %s", strerror(errno));
+			return 0;
+		}
+	}
+
+retry_once:
+	while ((entry = readdir(dir)) != NULL) {
+		if (entry->d_type == DT_DIR && strcmp(entry->d_name, ".") != 0 &&
+		    strcmp(entry->d_name, "..") != 0) {
+			snprintf(ring_path, sizeof(ring_path), "%s/%s/ring",
+				 FCOPY_CHANNELS_PATH, entry->d_name);
+
+			if (stat(ring_path, &st) == 0) {
+				/*
+				 * stat returns size of Tx, Rx rings combined,
+				 * so take half of it for individual ring size.
+				 */
+				ring_size = (uint32_t)st.st_size / 2;
+				syslog(LOG_INFO, "Ring buffer size from %s: %u bytes",
+				       ring_path, ring_size);
+				break;
+			}
+		}
+	}
+
+	if (!ring_size && retry_count == 0) {
+		retry_count = 1;
+		rewinddir(dir);
+		usleep(100 * 1000); /* Wait 100ms and retry once */
+		goto retry_once;
+	}
+
+	closedir(dir);
 
-static unsigned char desc[HV_RING_SIZE];
+	if (!ring_size)
+		syslog(LOG_ERR, "Could not determine ring size");
+
+	return ring_size;
+}
+
+static unsigned char *desc;
 
 static int target_fd;
 static char target_fname[PATH_MAX];
@@ -62,8 +118,11 @@ static int hv_fcopy_create_file(char *file_name, char *path_name, __u32 flags)
 
 	filesize = 0;
 	p = path_name;
-	snprintf(target_fname, sizeof(target_fname), "%s/%s",
-		 path_name, file_name);
+	if (snprintf(target_fname, sizeof(target_fname), "%s/%s",
+		     path_name, file_name) >= sizeof(target_fname)) {
+		syslog(LOG_ERR, "target file name is too long: %s/%s", path_name, file_name);
+		goto done;
+	}
 
 	/*
 	 * Check to see if the path is already in place; if not,
@@ -270,7 +329,7 @@ static void wcstoutf8(char *dest, const __u16 *src, size_t dest_size)
 {
 	size_t len = 0;
 
-	while (len < dest_size) {
+	while (len < dest_size && *src) {
 		if (src[len] < 0x80)
 			dest[len++] = (char)(*src++);
 		else
@@ -282,27 +341,15 @@ static void wcstoutf8(char *dest, const __u16 *src, size_t dest_size)
 
 static int hv_fcopy_start(struct hv_start_fcopy *smsg_in)
 {
-	setlocale(LC_ALL, "en_US.utf8");
-	size_t file_size, path_size;
-	char *file_name, *path_name;
-	char *in_file_name = (char *)smsg_in->file_name;
-	char *in_path_name = (char *)smsg_in->path_name;
-
-	file_size = wcstombs(NULL, (const wchar_t *restrict)in_file_name, 0) + 1;
-	path_size = wcstombs(NULL, (const wchar_t *restrict)in_path_name, 0) + 1;
-
-	file_name = (char *)malloc(file_size * sizeof(char));
-	path_name = (char *)malloc(path_size * sizeof(char));
-
-	if (!file_name || !path_name) {
-		free(file_name);
-		free(path_name);
-		syslog(LOG_ERR, "Can't allocate memory for file name and/or path name");
-		return HV_E_FAIL;
-	}
+	/*
+	 * file_name and path_name should have same length with appropriate
+	 * member of hv_start_fcopy.
+	 */
+	char file_name[W_MAX_PATH], path_name[W_MAX_PATH];
 
-	wcstoutf8(file_name, (__u16 *)in_file_name, file_size);
-	wcstoutf8(path_name, (__u16 *)in_path_name, path_size);
+	setlocale(LC_ALL, "en_US.utf8");
+	wcstoutf8(file_name, smsg_in->file_name, W_MAX_PATH - 1);
+	wcstoutf8(path_name, smsg_in->path_name, W_MAX_PATH - 1);
 
 	return hv_fcopy_create_file(file_name, path_name, smsg_in->copy_flags);
 }
@@ -406,7 +453,7 @@ int main(int argc, char *argv[])
 	int daemonize = 1, long_index = 0, opt, ret = -EINVAL;
 	struct vmbus_br txbr, rxbr;
 	void *ring;
-	uint32_t len = HV_RING_SIZE;
+	uint32_t ring_size, len;
 	char uio_name[NAME_MAX] = {0};
 	char uio_dev_path[PATH_MAX] = {0};
 
@@ -437,7 +484,20 @@ int main(int argc, char *argv[])
 	openlog("HV_UIO_FCOPY", 0, LOG_USER);
 	syslog(LOG_INFO, "starting; pid is:%d", getpid());
 
-	fcopy_get_first_folder(FCOPY_UIO, uio_name);
+	ring_size = get_ring_buffer_size();
+	if (!ring_size) {
+		ret = -ENODEV;
+		goto exit;
+	}
+
+	desc = malloc(ring_size * sizeof(unsigned char));
+	if (!desc) {
+		syslog(LOG_ERR, "malloc failed for desc buffer");
+		ret = -ENOMEM;
+		goto exit;
+	}
+
+	fcopy_get_first_folder(FCOPY_UIO_PATH, uio_name);
 	snprintf(uio_dev_path, sizeof(uio_dev_path), "/dev/%s", uio_name);
 	fcopy_fd = open(uio_dev_path, O_RDWR);
 
@@ -445,17 +505,17 @@ int main(int argc, char *argv[])
 		syslog(LOG_ERR, "open %s failed; error: %d %s",
 		       uio_dev_path, errno, strerror(errno));
 		ret = fcopy_fd;
-		goto exit;
+		goto free_desc;
 	}
 
-	ring = vmbus_uio_map(&fcopy_fd, HV_RING_SIZE);
+	ring = vmbus_uio_map(&fcopy_fd, ring_size);
 	if (!ring) {
 		ret = errno;
 		syslog(LOG_ERR, "mmap ringbuffer failed; error: %d %s", ret, strerror(ret));
 		goto close;
 	}
-	vmbus_br_setup(&txbr, ring, HV_RING_SIZE);
-	vmbus_br_setup(&rxbr, (char *)ring + HV_RING_SIZE, HV_RING_SIZE);
+	vmbus_br_setup(&txbr, ring, ring_size);
+	vmbus_br_setup(&rxbr, (char *)ring + ring_size, ring_size);
 
 	rxbr.vbr->imask = 0;
 
@@ -472,7 +532,7 @@ int main(int argc, char *argv[])
 			goto close;
 		}
 
-		len = HV_RING_SIZE;
+		len = ring_size;
 		ret = rte_vmbus_chan_recv_raw(&rxbr, desc, &len);
 		if (unlikely(ret <= 0)) {
 			/* This indicates a failure to communicate (or worse) */
@@ -492,6 +552,8 @@ int main(int argc, char *argv[])
 	}
 close:
 	close(fcopy_fd);
+free_desc:
+	free(desc);
 exit:
 	return ret;
 }