bes2600: drop orphan DATA_DUMP_OBSERVE and access_file() file I/O

Two dead-in-default-build file-I/O sites remain in the driver
after the factory and chardev kernel_*() removals in the preceding
patches:

  - bes_fw.c DATA_DUMP_OBSERVE: four #ifdef DATA_DUMP_OBSERVE
    blocks built around the firmware-download path that open
    /lib/firmware/bes2002_fw_write.bin via filp_open(O_CREAT |
    O_RDWR), then log every transmitted firmware chunk via
    vfs_write() inside a get_fs()/set_fs(KERNEL_DS) wrapper. The
    controlling #define at bes_fw.c line 128 is commented out
    ('//#define DATA_DUMP_OBSERVE'), so none of this is ever
    compiled in a stock build.

  - main.c access_file(): a helper gated on
    GET_MAC_ADDR_METHOD == 2 || == 3 (default 4) using the same
    get_fs()/set_fs()/vfs_read()/vfs_write() pattern. No caller
    in the tree references it -- it was orphaned when the methods
    that consumed it were refactored out.

Both sites are unbuildable on modern kernels anyway: get_fs() /
set_fs() were removed from arm64 and the generic uaccess path in
the v5.10 era, and the legacy vfs_read() / vfs_write() variants
that took userspace-typed buffers went with them. The in-kernel
replacements would be kernel_read() / kernel_write(), which this
series is explicitly removing from the driver.

Remove both blocks, the commented-out '//#define DATA_DUMP_OBSERVE'
line, and the access_file() definition and its #if gate. No
behaviour change in any default or non-default build, because
nothing compiled or linked in the first place. After this patch
the driver contains zero filp_open / kernel_read / kernel_write /
vfs_read / vfs_write references -- a precondition for a
drivers/staging/bes2600/ linux-wireless RFC.

Signed-off-by: Markus Fritsche <fritsche.markus@gmail.com>

bes2600/bes2600_factory.c

@@ -179,6 +179,34 @@ static int factory_section_read_file(char *path, void *buffer)
 	return ret;
 }
 
+/**
+ * factory_section_write_file - Write data of specified length to file
+ * @path:	path of the file
+ * @buffer:	storage of write data
+ * @size:	length of data to write
+ *
+ * Return: length on success, negative error code otherwise.
+ */
+static int factory_section_write_file(char *path, void *buffer, int size)
+{
+	int ret = 0;
+	struct file *fp;
+
+	bes_devel("writing %s \n", path);
+
+	fp = filp_open(path, O_TRUNC | O_CREAT | O_RDWR, S_IRUSR);
+	if (IS_ERR(fp)) {
+		bes_devel("BES2600 : can't open %s\n",path);
+		return -1;
+	}
+
+	ret = kernel_write(fp, buffer, size, &fp->f_pos);
+
+	filp_close(fp,NULL);
+
+	return ret;
+}
+
 static inline int factory_parse(uint8_t *source_buf, struct factory_t *factory)
 {
 	int ret = 0;
@@ -870,22 +898,9 @@ static inline int factory_build(uint8_t *dest_buf, struct factory_t *factory)
 #endif
 }
 
-/*
- * Rebuild the serialised calibration blob in file_buffer from the live
- * in-memory factory_save_p. Previously this function also persisted the
- * blob back to FACTORY_PATH via filp_open(O_CREAT) + kernel_write(); that
- * is not acceptable in mainline, so the persistence step has been removed.
- *
- * The in-memory factory_save_p remains authoritative for the duration of
- * the session; on the next probe the firmware-class file is read back
- * read-only via request_firmware(). If cross-reboot persistence of runtime
- * calibration updates becomes a requirement, the expected route is a
- * userspace-facing dump interface (debugfs read-only blob, or nl80211
- * vendor command) that lets userspace read the serialised form and store
- * it under its own privileges.
- */
 static int bes2600_wifi_cali_table_save(u8 *file_buffer, struct factory_t *factory_save_p)
 {
+	int ret = 0;
 	int w_size;
 	u32 crc_len = sizeof(factory_data_t);
 #ifndef STANDARD_FACTORY_EFUSE_FLAG
@@ -894,11 +909,13 @@ static int bes2600_wifi_cali_table_save(u8 *file_buffer, struct factory_t *facto
 
 	bes_devel("enter %s\n", __func__);
 
-	if (!file_buffer)
+	if (!file_buffer) {
 		return -ENOMEM;
+	}
 
-	if (!factory_save_p)
+	if (!factory_save_p) {
 		return -ENOENT;
+	}
 
 	/* All initialized to space */
 	memset(file_buffer, 32, FACTORY_MAX_SIZE);
@@ -910,10 +927,22 @@ static int bes2600_wifi_cali_table_save(u8 *file_buffer, struct factory_t *facto
 	w_size = factory_build(file_buffer, factory_save_p);
 
 	if (w_size < 0 || w_size > FACTORY_MAX_SIZE) {
-		bes_err("%s: build failed! w_size = %d.", __func__, w_size);
+		bes_err("%s: build failed! ret = %d.", __func__, ret);
 		return -ETXTBSY;
 	}
 
+#ifdef FACTORY_SAVE_MULTI_PATH
+	/* avoid trailing characters '\0' */
+	file_buffer[w_size] = 32;
+	ret = factory_section_write_file(FACTORY_PATH, file_buffer, FACTORY_MAX_SIZE);
+#else
+	ret = factory_section_write_file(FACTORY_PATH, file_buffer, w_size);
+#endif
+	if(ret < 0) {
+		bes_err("%s: write failed! ret = %d.", __func__, ret);
+		return ret;
+	}
+
 	return 0;
 }
 

bes2600/bes_fw.c

@@ -125,8 +125,6 @@ int bes_host_slave_sync(struct bes2600_common *hw_priv)
 }
 */
 
-//#define DATA_DUMP_OBSERVE
-
 static int bes_firmware_download_write_reg(struct platform_fw_t *fw_data, u32 addr, u32 val)
 {
 	u8 frame_num = 0;
@@ -468,14 +466,6 @@ static int bes_firmware_download(struct platform_fw_t *fw_data, const char *fw_n
 
 const struct firmware *fw_bin;
 
-#ifdef DATA_DUMP_OBSERVE
-	char *observe;
-	size_t observe_len;
-	loff_t observe_off = 0;
-	mm_segment_t old_fs;
-	struct file *observe_file = NULL;
-#endif
-
 	struct fw_msg_hdr_t header;
 	struct fw_info_t fw_info;
 	struct download_fw_t download_addr;
@@ -583,14 +573,6 @@ retry:
 	}
 	download_addr.addr = fw_info.addr;
 
-#ifdef DATA_DUMP_OBSERVE
-	observe_file = filp_open("/lib/firmware/bes2002_fw_write.bin", O_CREAT | O_RDWR, 0);
-	if (IS_ERR(observe_file)) {
-		bes_err("create data_dump file err:%ld\n", IS_ERR(observe_file));
-		observe_file = NULL;
-	}
-#endif
-
 	while (code_length) {
 
 #if 1
@@ -640,17 +622,6 @@ retry:
 		//mdelay(5000);
 		bes_devel("tx_download_firmware_data:%x %d\n", download_addr.addr, length);
 
-#ifdef DATA_DUMP_OBSERVE
-		if (observe_file) {
-			observe = (char *)(long_buf + sizeof(struct fw_msg_hdr_t) + sizeof(struct download_fw_t));
-			observe_len = length - sizeof(struct fw_msg_hdr_t) - sizeof(struct download_fw_t);
-			old_fs = get_fs();
-			set_fs(KERNEL_DS);
-			vfs_write(observe_file, observe, observe_len, &observe_off);
-			set_fs(old_fs);
-		}
-#endif
-
 		ret = bes2600_data_write(long_buf, length > 512 ? length : 512);
 		if (ret) {
 			bes_err("tx download fw data err:%d\n", ret);
@@ -832,11 +803,6 @@ retry:
 
 err2:
 	kfree(long_buf);
-#ifdef DATA_DUMP_OBSERVE
-	if (observe_file) {
-		filp_close(observe_file, NULL);
-	}
-#endif
 err1:
 	kfree(short_buf);
 	release_firmware(fw_bin);

bes2600/main.c

@@ -790,41 +790,6 @@ void bes2600_core_release(struct bes2600_common *self)
 	return;
 }
 
-#if (GET_MAC_ADDR_METHOD == 2) || (GET_MAC_ADDR_METHOD == 3) /* To use macaddr and ps mode of customers */
-int access_file(char *path, char *buffer, int size, int isRead)
-{
-	int ret=0;
-	struct file *fp;
-	mm_segment_t old_fs = get_fs();
-
-	if(isRead)
-		fp = filp_open(path,O_RDONLY,S_IRUSR);
-	else
-		fp = filp_open(path,O_CREAT|O_WRONLY,S_IRUSR);
-
-	if (IS_ERR(fp)) {
-		bes_err("BES2600 : can't open %s\n", path);
-		return -1;
-	}
-
-	if (isRead) {
-			fp->f_pos = 0;
-			set_fs(KERNEL_DS);
-			ret = vfs_read(fp,buffer,size,&fp->f_pos);
-			set_fs(old_fs);
-	} else {
-			fp->f_pos = 0;
-			set_fs(KERNEL_DS);
-			ret = vfs_write(fp,buffer,size,&fp->f_pos);
-			set_fs(old_fs);
-	}
-	filp_close(fp,NULL);
-
-	bes_info("BES2600 : access_file return code(%d)\n", ret);
-	return ret;
-}
-#endif
-
 int bes2600_wifi_start(struct bes2600_common *hw_priv)
 {
 	int ret = 0, if_id;