[PATCH v2 27/41] bootstd: Add an implementation of distro boot
Simon Glass
sjg at chromium.org
Sun Oct 24 01:26:21 CEST 2021
Add a bootmeth driver which handles distro boot from a disk, so we can
boot a bootflow using this commonly used mechanism.
In effect, this provides the same functionality as the 'sysboot' command
and shares the same code. But the interface into it is via a bootmeth.
For now this requires the 'pxe' command be enabled. Future work may tidy
this up so that it can be used without CONFIG_CMDLINE being enabled.
Signed-off-by: Simon Glass <sjg at chromium.org>
---
(no changes since v1)
MAINTAINERS | 3 +-
boot/Kconfig | 15 +++
boot/Makefile | 2 +
boot/bootmeth_distro.c | 217 +++++++++++++++++++++++++++++++++++++++++
include/distro.h | 24 +++++
5 files changed, 260 insertions(+), 1 deletion(-)
create mode 100644 boot/bootmeth_distro.c
create mode 100644 include/distro.h
diff --git a/MAINTAINERS b/MAINTAINERS
index a95329286da..fc05570f11d 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -641,7 +641,8 @@ F: boot/bootflow.c
F: boot/bootmeth*.c
F: boot/bootstd.c
F: cmd/bootdev.c
-F: include/bootdev*.h
+F: cmd/bootflow.c
+F: include/bootdev.h
F: include/bootflow.h
F: include/bootmeth.h
F: include/bootstd.h
diff --git a/boot/Kconfig b/boot/Kconfig
index 58c495bb347..c5c8be70da9 100644
--- a/boot/Kconfig
+++ b/boot/Kconfig
@@ -295,6 +295,21 @@ config BOOTSTD
U-Boot)
- bootflow - a description of how to boot (owned by the distro)
+if BOOTSTD
+
+config BOOTMETH_DISTRO
+ bool "Bootdev support for distro boot"
+ depends on CMD_PXE
+ default y
+ help
+ Enables support for distro boot using bootdevs. This makes the
+ bootdevs look for a 'extlinux/extlinux.conf' on each filesystem
+ they scan.
+
+ This provides a way to try out standard boot on an existing boot flow.
+
+endif
+
config LEGACY_IMAGE_FORMAT
bool "Enable support for the legacy image format"
default y if !FIT_SIGNATURE
diff --git a/boot/Makefile b/boot/Makefile
index f58c192ae07..d8f5c340b85 100644
--- a/boot/Makefile
+++ b/boot/Makefile
@@ -28,6 +28,8 @@ obj-$(CONFIG_$(SPL_TPL_)BOOTSTD) += bootflow.o
obj-$(CONFIG_$(SPL_TPL_)BOOTSTD) += bootmeth-uclass.o
obj-$(CONFIG_$(SPL_TPL_)BOOTSTD) += bootstd-uclass.o
+obj-$(CONFIG_$(SPL_TPL_)BOOTMETH_DISTRO) += bootmeth_distro.o
+
obj-$(CONFIG_$(SPL_TPL_)OF_LIBFDT) += image-fdt.o
obj-$(CONFIG_$(SPL_TPL_)FIT_SIGNATURE) += fdt_region.o
obj-$(CONFIG_$(SPL_TPL_)FIT) += image-fit.o
diff --git a/boot/bootmeth_distro.c b/boot/bootmeth_distro.c
new file mode 100644
index 00000000000..551159abff3
--- /dev/null
+++ b/boot/bootmeth_distro.c
@@ -0,0 +1,217 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Bootmethod for distro boot (syslinux boot from a block device)
+ *
+ * Copyright 2021 Google LLC
+ * Written by Simon Glass <sjg at chromium.org>
+ */
+
+#include <common.h>
+#include <bootdev.h>
+#include <bootflow.h>
+#include <bootmeth.h>
+#include <bootstd.h>
+#include <command.h>
+#include <distro.h>
+#include <dm.h>
+#include <fs.h>
+#include <malloc.h>
+#include <mapmem.h>
+#include <mmc.h>
+#include <pxe_utils.h>
+
+static int disto_getfile(struct pxe_context *ctx, const char *file_path,
+ char *file_addr, ulong *sizep)
+{
+ struct distro_info *info = ctx->userdata;
+ ulong addr;
+ int ret;
+
+ addr = simple_strtoul(file_addr, NULL, 16);
+
+ /* Allow up to 1GB */
+ *sizep = 1 << 30;
+ ret = bootmeth_read_file(info->dev, info->bflow, file_path, addr,
+ sizep);
+ if (ret)
+ return log_msg_ret("read", ret);
+
+ return 0;
+}
+
+static int distro_check(struct udevice *dev, struct bootflow_iter *iter)
+{
+ int ret;
+
+ /* This only works on block devices */
+ ret = bootflow_iter_uses_blk_dev(iter);
+ if (ret)
+ return log_msg_ret("blk", ret);
+
+ return 0;
+}
+
+static int distro_read_bootflow(struct udevice *dev, struct bootflow *bflow)
+{
+ struct blk_desc *desc = dev_get_uclass_plat(bflow->blk);
+ const char *const *prefixes;
+ struct udevice *bootstd;
+ loff_t size, bytes_read;
+ char fname[200];
+ ulong addr;
+ int ret, i;
+ char *buf;
+
+ ret = uclass_first_device_err(UCLASS_BOOTSTD, &bootstd);
+ if (ret)
+ return log_msg_ret("std", ret);
+
+ /* We require a partition table */
+ if (!bflow->part)
+ return -ENOENT;
+
+ bflow->fname = strdup(DISTRO_FNAME);
+ if (!bflow->fname)
+ return log_msg_ret("name", -ENOMEM);
+
+ prefixes = bootstd_get_prefixes(bootstd);
+ if (prefixes) {
+ log_debug("Trying prefixes:\n");
+ for (i = 0; prefixes[i]; i++) {
+ snprintf(fname, sizeof(fname), "%s%s", prefixes[i],
+ DISTRO_FNAME);
+ ret = fs_size(fname, &size);
+ log_debug(" %s - err=%d\n", fname, ret);
+ if (!ret)
+ break;
+
+ /*
+ * Sadly FS closes the file after fs_size() so we must
+ * redo this
+ */
+ ret = fs_set_blk_dev_with_part(desc, bflow->part);
+ if (ret)
+ return log_msg_ret("set", ret);
+ }
+ log_debug(" done\n");
+ } else {
+ strcpy(fname, DISTRO_FNAME);
+ ret = fs_size(bflow->fname, &size);
+ log_debug("No prefixes: %s - err=%d", fname, ret);
+ }
+ if (ret)
+ return log_msg_ret("size", ret);
+
+ bflow->fname = strdup(fname);
+ if (!bflow->fname)
+ return log_msg_ret("name", -ENOMEM);
+
+ bflow->state = BOOTFLOWST_FILE;
+ bflow->size = size;
+ log_debug(" - distro file size %x\n", (uint)size);
+ if (size > 0x10000)
+ return log_msg_ret("chk", -E2BIG);
+
+ /* Sadly FS closes the file after fs_size() so we must redo this */
+ ret = fs_set_blk_dev_with_part(desc, bflow->part);
+ if (ret)
+ return log_msg_ret("set", ret);
+
+ buf = malloc(size + 1);
+ if (!buf)
+ return log_msg_ret("buf", -ENOMEM);
+ addr = map_to_sysmem(buf);
+
+ ret = fs_read(bflow->fname, addr, 0, 0, &bytes_read);
+ if (ret) {
+ free(buf);
+ return log_msg_ret("read", ret);
+ }
+ if (size != bytes_read)
+ return log_msg_ret("bread", -EINVAL);
+ buf[size] = '\0';
+ bflow->state = BOOTFLOWST_READY;
+ bflow->buf = buf;
+
+ return 0;
+}
+
+static int distro_read_file(struct udevice *dev, struct bootflow *bflow,
+ const char *file_path, ulong addr, ulong *sizep)
+{
+ struct blk_desc *desc = dev_get_uclass_plat(bflow->blk);
+ loff_t len_read;
+ loff_t size;
+ int ret;
+
+ ret = fs_set_blk_dev_with_part(desc, bflow->part);
+ if (ret)
+ return log_msg_ret("set1", ret);
+ ret = fs_size(file_path, &size);
+ if (ret)
+ return log_msg_ret("size", ret);
+ if (size > *sizep)
+ return log_msg_ret("spc", -ENOSPC);
+
+ ret = fs_set_blk_dev_with_part(desc, bflow->part);
+ if (ret)
+ return log_msg_ret("set2", ret);
+ ret = fs_read(file_path, addr, 0, 0, &len_read);
+ if (ret)
+ return ret;
+ *sizep = len_read;
+
+ return 0;
+}
+
+static int distro_boot(struct udevice *dev, struct bootflow *bflow)
+{
+ struct cmd_tbl cmdtp = {}; /* dummy */
+ struct pxe_context ctx;
+ struct distro_info info;
+ ulong addr;
+ int ret;
+
+ addr = map_to_sysmem(bflow->buf);
+ info.dev = dev;
+ info.bflow = bflow;
+ ret = pxe_setup_ctx(&ctx, &cmdtp, disto_getfile, &info, true,
+ bflow->subdir);
+ if (ret)
+ return log_msg_ret("ctx", -EINVAL);
+
+ ret = pxe_process(&ctx, addr, false);
+ if (ret)
+ return log_msg_ret("bread", -EINVAL);
+
+ return 0;
+}
+
+static int distro_bootmeth_bind(struct udevice *dev)
+{
+ struct bootmeth_uc_plat *plat = dev_get_uclass_plat(dev);
+
+ plat->desc = "Syslinux boot from a block device";
+
+ return 0;
+}
+
+static struct bootmeth_ops distro_bootmeth_ops = {
+ .check = distro_check,
+ .read_bootflow = distro_read_bootflow,
+ .read_file = distro_read_file,
+ .boot = distro_boot,
+};
+
+static const struct udevice_id distro_bootmeth_ids[] = {
+ { .compatible = "u-boot,distro-syslinux" },
+ { }
+};
+
+U_BOOT_DRIVER(bootmeth_distro) = {
+ .name = "bootmeth_distro",
+ .id = UCLASS_BOOTMETH,
+ .of_match = distro_bootmeth_ids,
+ .ops = &distro_bootmeth_ops,
+ .bind = distro_bootmeth_bind,
+};
diff --git a/include/distro.h b/include/distro.h
new file mode 100644
index 00000000000..2ee145871b2
--- /dev/null
+++ b/include/distro.h
@@ -0,0 +1,24 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright 2021 Google LLC
+ * Written by Simon Glass <sjg at chromium.org>
+ */
+
+#ifndef __distro_h
+#define __distro_h
+
+#define DISTRO_FNAME "extlinux/extlinux.conf"
+
+/**
+ * struct distro_info - useful information for distro_getfile()
+ *
+ * @dev: bootmethod device being used to boot
+ * @bflow: bootflow being booted
+ */
+struct distro_info {
+ struct udevice *dev;
+ struct bootflow *bflow;
+ struct cmd_tbl *cmdtp;
+};
+
+#endif
--
2.33.0.1079.g6e70778dc9-goog
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