Boot entries generated from bootloader spec are currently sorted by the order the files are read from the file system.
This is inadequate if we have multiple entries with different kernels and we want to sort the newer kernels higher. The UAPI.1 Boot Loader Specification defines an algorithm[1] to order the entries that takes care of this, so implement it into barebox. [1]: https://uapi-group.org/specifications/specs/boot_loader_specification/#sorting Signed-off-by: Ahmad Fatoum <[email protected]> --- common/Kconfig | 1 + common/blspec.c | 62 ++++++++++++++++++++++++++++++++++++++- common/boot.c | 7 +++++ include/asm-generic/bug.h | 7 +++++ include/boot.h | 2 ++ 5 files changed, 78 insertions(+), 1 deletion(-) diff --git a/common/Kconfig b/common/Kconfig index 50c26695b2b5..cd002865f736 100644 --- a/common/Kconfig +++ b/common/Kconfig @@ -715,6 +715,7 @@ config BLSPEC select BOOT select BOOTM select OFTREE + select VERSION_CMP bool prompt "Support bootloader spec" help diff --git a/common/blspec.c b/common/blspec.c index 624e4c115272..f13e44f1de71 100644 --- a/common/blspec.c +++ b/common/blspec.c @@ -28,6 +28,7 @@ struct blspec_entry { struct cdev *cdev; const char *rootpath; const char *configpath; + char *sortkey; }; /* @@ -181,6 +182,7 @@ static void blspec_entry_free(struct bootentry *be) of_delete_node(entry->node); free_const(entry->configpath); free_const(entry->rootpath); + free(entry->sortkey); free(entry); } @@ -268,6 +270,12 @@ static struct blspec_entry *blspec_entry_open(struct bootentries *bootentries, } } + /* This will be read often during comparison, so we cache it */ + if (!strcmp(name, "sort-key")) { + entry->sortkey = xstrdup(val); + continue; + } + blspec_entry_var_set(entry, name, val); } @@ -414,6 +422,58 @@ static const char *get_blspec_prefix_path(const char *configname) return get_mounted_path(configname); } +static int blspec_compare(struct list_head *list_a, struct list_head *list_b) +{ + struct bootentry *be_a = container_of(list_a, struct bootentry, list); + struct bootentry *be_b = container_of(list_b, struct bootentry, list); + struct blspec_entry *a, *b; + const char *a_version, *b_version; + int r; + + /* The boot entry providers are called one by one and passed an empty + * list that's aggregated later, so we should only be encountering + * bootloader spec entries here. + */ + DEBUG_ASSERT(is_blspec_entry(be_a) && is_blspec_entry(be_b)); + + a = container_of(be_a, struct blspec_entry, entry); + b = container_of(be_b, struct blspec_entry, entry); + + a_version = a->configpath; + b_version = b->configpath; + + if (a->sortkey && b->sortkey) { + const char *a_machine_id, *b_machine_id; + + /* A-Z, increasing alphanumerical order */ + r = strcmp(a->sortkey, b->sortkey); + if (r != 0) + return r; + + a_machine_id = blspec_entry_var_get(a, "machine-id"); + b_machine_id = blspec_entry_var_get(b, "machine-id"); + + /* A-Z, increasing alphanumerical order) */ + r = strcmp_ptr(a_machine_id, b_machine_id); + if (r != 0) + return r; + + /* Will be compared in decreasing version order */ + a_version = blspec_entry_var_get(a, "version"); + b_version = blspec_entry_var_get(b, "version"); + } else if (a->sortkey != b->sortkey) { + /* If sort-key is set on one entry, it sorts earlier. */ + return a->sortkey ? -1 : 1; + } + + /* At the end, if necessary, when sort-key is not set or + * those fields are not set or are all equal, the boot loader + * should sort using the file name of the entry (decreasing + * version sort), with the suffix removed. + */ + return -strverscmp(a_version, b_version); +} + static int __blspec_scan_file(struct bootentries *bootentries, const char *root, const char *configname) { @@ -459,7 +519,7 @@ static int __blspec_scan_file(struct bootentries *bootentries, const char *root, entry->entry.me.type = MENU_ENTRY_NORMAL; entry->entry.release = blspec_entry_free; - bootentries_add_entry(bootentries, &entry->entry); + bootentries_add_entry_sorted(bootentries, &entry->entry, blspec_compare); return 1; } diff --git a/common/boot.c b/common/boot.c index 8ccc269ac5bd..2e5294ffa2f0 100644 --- a/common/boot.c +++ b/common/boot.c @@ -34,6 +34,13 @@ static inline void bootentries_merge(struct bootentries *dst, struct bootentries list_splice_tail_init(&src->entries, &dst->entries); } +void bootentries_add_entry_sorted(struct bootentries *entries, struct bootentry *entry, + int (*compare)(struct list_head *, struct list_head *)) + +{ + list_add_sort(&entry->list, &entries->entries, compare); +} + struct bootentries *bootentries_alloc(void) { struct bootentries *bootentries; diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h index 514801dab10e..1953c6e642c1 100644 --- a/include/asm-generic/bug.h +++ b/include/asm-generic/bug.h @@ -78,4 +78,11 @@ BUG_ON(!(expr)); \ } while (0) + +#ifdef DEBUG +#define DEBUG_ASSERT(expr) BUG_ON(!(expr)) +#else +#define DEBUG_ASSERT(expr) ((void)(expr)) +#endif + #endif diff --git a/include/boot.h b/include/boot.h index e6309b65a0c3..fdc108b7a21d 100644 --- a/include/boot.h +++ b/include/boot.h @@ -24,6 +24,8 @@ struct bootentry { }; int bootentries_add_entry(struct bootentries *entries, struct bootentry *entry); +void bootentries_add_entry_sorted(struct bootentries *entries, struct bootentry *entry, + int (*compare)(struct list_head *, struct list_head *)); struct bootentry_provider { const char *name; -- 2.47.3
