pxe: Return the file size from the getfile() function

It is pretty strange that the pxe code uses the 'filesize' environment
variable find the size of a file it has just read.

Partly this is because it uses the command-line interpreter to parse its
request to load the file.

As a first step towards unwinding this, return it directly from the
getfile() function. This makes the code a bit longer, for now, but will be
cleaned up in future patches.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Artem Lapkin <email2tema@gmail.com>
Tested-by: Artem Lapkin <email2tema@gmail.com>
Reviewed-by: Ramon Fried <rfried.dev@gmail.com>

4 files changed, 79 insertions, 32 deletions

diff --git a/boot/pxe_utils.c b/boot/pxe_utils.c
index 48fb7076fd1..a7a84f26c1d 100644
--- a/boot/pxe_utils.c
+++ b/boot/pxe_utils.c
@@ -30,6 +30,20 @@
 
 #define MAX_TFTP_PATH_LEN 512
 
+int pxe_get_file_size(ulong *sizep)
+{
+	const char *val;
+
+	val = from_env("filesize");
+	if (!val)
+		return -ENOENT;
+
+	if (strict_strtoul(val, 16, sizep) < 0)
+		return -EINVAL;
+
+	return 0;
+}
+
 /**
  * format_mac_pxe() - obtain a MAC address in the PXE format
  *
@@ -75,14 +89,17 @@ int format_mac_pxe(char *outbuf, size_t outbuf_len)
  * @ctx: PXE context
  * @file_path: File path to read (relative to the PXE file)
  * @file_addr: Address to load file to
+ * @filesizep: If not NULL, returns the file size in bytes
  * Returns 1 for success, or < 0 on error
  */
 static int get_relfile(struct pxe_context *ctx, const char *file_path,
-		       unsigned long file_addr)
+		       unsigned long file_addr, ulong *filesizep)
 {
 	size_t path_len;
 	char relfile[MAX_TFTP_PATH_LEN + 1];
 	char addr_buf[18];
+	ulong size;
+	int ret;
 
 	if (file_path[0] == '/' && ctx->allow_abs_path)
 		*relfile = '\0';
@@ -103,7 +120,13 @@ static int get_relfile(struct pxe_context *ctx, const char *file_path,
 
 	sprintf(addr_buf, "%lx", file_addr);
 
-	return ctx->getfile(ctx, relfile, addr_buf);
+	ret = ctx->getfile(ctx, relfile, addr_buf, &size);
+	if (ret < 0)
+		return log_msg_ret("get", ret);
+	if (filesizep)
+		*filesizep = size;
+
+	return 1;
 }
 
 /**
@@ -117,29 +140,17 @@ static int get_relfile(struct pxe_context *ctx, const char *file_path,
  * Returns 1 for success, or < 0 on error
  */
 int get_pxe_file(struct pxe_context *ctx, const char *file_path,
-		 unsigned long file_addr)
+		 ulong file_addr)
 {
-	unsigned long config_file_size;
-	char *tftp_filesize;
+	ulong size;
 	int err;
 	char *buf;
 
-	err = get_relfile(ctx, file_path, file_addr);
+	err = get_relfile(ctx, file_path, file_addr, &size);
 	if (err < 0)
 		return err;
 
-	/*
-	 * the file comes without a NUL byte at the end, so find out its size
-	 * and add the NUL byte.
-	 */
-	tftp_filesize = from_env("filesize");
-	if (!tftp_filesize)
-		return -ENOENT;
-
-	if (strict_strtoul(tftp_filesize, 16, &config_file_size) < 0)
-		return -EINVAL;
-
-	buf = map_sysmem(file_addr + config_file_size, 1);
+	buf = map_sysmem(file_addr + size, 1);
 	*buf = '\0';
 	unmap_sysmem(buf);
 
@@ -184,12 +195,13 @@ int get_pxelinux_path(struct pxe_context *ctx, const char *file,
  * @file_path: File path to read (relative to the PXE file)
  * @envaddr_name: Name of environment variable which contains the address to
  *	load to
+ * @filesizep: Returns the file size in bytes
  * Returns 1 on success, -ENOENT if @envaddr_name does not exist as an
  *	environment variable, -EINVAL if its format is not valid hex, or other
  *	value < 0 on other error
  */
 static int get_relfile_envaddr(struct pxe_context *ctx, const char *file_path,
-			       const char *envaddr_name)
+			       const char *envaddr_name, ulong *filesizep)
 {
 	unsigned long file_addr;
 	char *envaddr;
@@ -201,7 +213,7 @@ static int get_relfile_envaddr(struct pxe_context *ctx, const char *file_path,
 	if (strict_strtoul(envaddr, 16, &file_addr) < 0)
 		return -EINVAL;
 
-	return get_relfile(ctx, file_path, file_addr);
+	return get_relfile(ctx, file_path, file_addr, filesizep);
 }
 
 /**
@@ -357,8 +369,8 @@ static void label_boot_fdtoverlay(struct pxe_context *ctx,
 			goto skip_overlay;
 
 		/* Load overlay file */
-		err = get_relfile_envaddr(ctx, overlayfile,
-					  "fdtoverlay_addr_r");
+		err = get_relfile_envaddr(ctx, overlayfile, "fdtoverlay_addr_r",
+					  NULL);
 		if (err < 0) {
 			printf("Failed loading overlay %s\n", overlayfile);
 			goto skip_overlay;
@@ -443,21 +455,25 @@ static int label_boot(struct pxe_context *ctx, struct pxe_label *label)
 	}
 
 	if (label->initrd) {
-		if (get_relfile_envaddr(ctx, label->initrd, "ramdisk_addr_r") < 0) {
+		ulong size;
+
+		if (get_relfile_envaddr(ctx, label->initrd, "ramdisk_addr_r",
+					&size) < 0) {
 			printf("Skipping %s for failure retrieving initrd\n",
 			       label->name);
 			return 1;
 		}
 
 		initrd_addr_str = env_get("ramdisk_addr_r");
-		strncpy(initrd_filesize, env_get("filesize"), 9);
+		strcpy(initrd_filesize, simple_xtoa(size));
 
 		strncpy(initrd_str, initrd_addr_str, 18);
 		strcat(initrd_str, ":");
 		strncat(initrd_str, initrd_filesize, 9);
 	}
 
-	if (get_relfile_envaddr(ctx, label->kernel, "kernel_addr_r") < 0) {
+	if (get_relfile_envaddr(ctx, label->kernel, "kernel_addr_r",
+				NULL) < 0) {
 		printf("Skipping %s for failure retrieving kernel\n",
 		       label->name);
 		return 1;
@@ -599,7 +615,7 @@ static int label_boot(struct pxe_context *ctx, struct pxe_label *label)
 
 		if (fdtfile) {
 			int err = get_relfile_envaddr(ctx, fdtfile,
-						      "fdt_addr_r");
+						      "fdt_addr_r", NULL);
 
 			free(fdtfilefree);
 			if (err < 0) {
@@ -1403,7 +1419,7 @@ void handle_pxe_menu(struct pxe_context *ctx, struct pxe_menu *cfg)
 	if (IS_ENABLED(CONFIG_CMD_BMP)) {
 		/* display BMP if available */
 		if (cfg->bmp) {
-			if (get_relfile(ctx, cfg->bmp, image_load_addr)) {
+			if (get_relfile(ctx, cfg->bmp, image_load_addr, NULL)) {
 				if (CONFIG_IS_ENABLED(CMD_CLS))
 					run_command("cls", 0);
 				bmp_display(image_load_addr,
diff --git a/cmd/pxe.c b/cmd/pxe.c
index e319db51ef5..81703386c42 100644
--- a/cmd/pxe.c
+++ b/cmd/pxe.c
@@ -25,15 +25,20 @@ const char *pxe_default_paths[] = {
 };
 
 static int do_get_tftp(struct pxe_context *ctx, const char *file_path,
-		       char *file_addr)
+		       char *file_addr, ulong *sizep)
 {
 	char *tftp_argv[] = {"tftp", NULL, NULL, NULL};
+	int ret;
 
 	tftp_argv[1] = file_addr;
 	tftp_argv[2] = (void *)file_path;
 
 	if (do_tftpb(ctx->cmdtp, 0, 3, tftp_argv))
 		return -ENOENT;
+	ret = pxe_get_file_size(sizep);
+	if (ret)
+		return log_msg_ret("tftp", ret);
+	ctx->pxe_file_size = *sizep;
 
 	return 1;
 }
diff --git a/cmd/sysboot.c b/cmd/sysboot.c
index c45fed774d6..6344ecd357b 100644
--- a/cmd/sysboot.c
+++ b/cmd/sysboot.c
@@ -9,43 +9,58 @@
 static char *fs_argv[5];
 
 static int do_get_ext2(struct pxe_context *ctx, const char *file_path,
-		       char *file_addr)
+		       char *file_addr, ulong *sizep)
 {
 #ifdef CONFIG_CMD_EXT2
+	int ret;
+
 	fs_argv[0] = "ext2load";
 	fs_argv[3] = file_addr;
 	fs_argv[4] = (void *)file_path;
 
 	if (!do_ext2load(ctx->cmdtp, 0, 5, fs_argv))
 		return 1;
+	ret = pxe_get_file_size(sizep);
+	if (ret)
+		return log_msg_ret("tftp", ret);
 #endif
 	return -ENOENT;
 }
 
 static int do_get_fat(struct pxe_context *ctx, const char *file_path,
-		      char *file_addr)
+		      char *file_addr, ulong *sizep)
 {
 #ifdef CONFIG_CMD_FAT
+	int ret;
+
 	fs_argv[0] = "fatload";
 	fs_argv[3] = file_addr;
 	fs_argv[4] = (void *)file_path;
 
 	if (!do_fat_fsload(ctx->cmdtp, 0, 5, fs_argv))
 		return 1;
+	ret = pxe_get_file_size(sizep);
+	if (ret)
+		return log_msg_ret("tftp", ret);
 #endif
 	return -ENOENT;
 }
 
 static int do_get_any(struct pxe_context *ctx, const char *file_path,
-		      char *file_addr)
+		      char *file_addr, ulong *sizep)
 {
 #ifdef CONFIG_CMD_FS_GENERIC
+	int ret;
+
 	fs_argv[0] = "load";
 	fs_argv[3] = file_addr;
 	fs_argv[4] = (void *)file_path;
 
 	if (!do_load(ctx->cmdtp, 0, 5, fs_argv, FS_TYPE_ANY))
 		return 1;
+	ret = pxe_get_file_size(sizep);
+	if (ret)
+		return log_msg_ret("tftp", ret);
 #endif
 	return -ENOENT;
 }
diff --git a/include/pxe_utils.h b/include/pxe_utils.h
index 8b50f2e6861..194a5ed8cc7 100644
--- a/include/pxe_utils.h
+++ b/include/pxe_utils.h
@@ -77,7 +77,7 @@ struct pxe_menu {
 
 struct pxe_context;
 typedef int (*pxe_getfile_func)(struct pxe_context *ctx, const char *file_path,
-				char *file_addr);
+				char *file_addr, ulong *filesizep);
 
 /**
  * struct pxe_context - context information for PXE parsing
@@ -88,6 +88,7 @@ typedef int (*pxe_getfile_func)(struct pxe_context *ctx, const char *file_path,
  * @allow_abs_path: true to allow absolute paths
  * @bootdir: Directory that files are loaded from ("" if no directory). This is
  *	allocated
+ * @pxe_file_size: Size of the PXE file
  */
 struct pxe_context {
 	struct cmd_tbl *cmdtp;
@@ -98,6 +99,7 @@ struct pxe_context {
 	 * @file_path: Path to the file
 	 * @file_addr: String containing the hex address to put the file in
 	 *	memory
+	 * @filesizep: Returns the file size in bytes
 	 * Return 0 if OK, -ve on error
 	 */
 	pxe_getfile_func getfile;
@@ -105,6 +107,7 @@ struct pxe_context {
 	void *userdata;
 	bool allow_abs_path;
 	char *bootdir;
+	ulong pxe_file_size;
 };
 
 /**
@@ -225,4 +228,12 @@ void pxe_destroy_ctx(struct pxe_context *ctx);
  */
 int pxe_process(struct pxe_context *ctx, ulong pxefile_addr_r, bool prompt);
 
+/**
+ * pxe_get_file_size() - Read the value of the 'filesize' environment variable
+ *
+ * @sizep: Place to put the value
+ * @return 0 if OK, -ENOENT if no such variable, -EINVAL if format is invalid
+ */
+int pxe_get_file_size(ulong *sizep);
+
 #endif /* __PXE_UTILS_H */