llext_manager: convert to use new LLEXT inspection API

This patch converts the llext_manager to use the new LLEXT inspection
API. The new API allows to get information about sections and regions
without the need to access the internal structures of the LLEXT loader,
decoupling SOF and LLEXT code and making it easier to maintain.

Signed-off-by: Luca Burelli <l.burelli@arduino.cc>

Author: pillo79

src/library_manager/llext_manager.c

@@ -28,6 +28,7 @@
 #include <zephyr/llext/buf_loader.h>
 #include <zephyr/llext/loader.h>
 #include <zephyr/llext/llext.h>
+#include <zephyr/llext/inspect.h>
 
 #include <rimage/sof/user/manifest.h>
 #include <module/module/api_ver.h>
@@ -69,37 +70,37 @@ static int llext_manager_align_unmap(void __sparse_cache *vma, size_t size)
 	return sys_mm_drv_unmap_region(aligned_vma, ALIGN_UP(pre_pad_size + size, PAGE_SZ));
 }
 
-static int llext_manager_load_data_from_storage(const struct llext *ext,
+static int llext_manager_load_data_from_storage(const struct llext_loader *ldr,
+						const struct llext *ext,
+						enum llext_mem region,
 						void __sparse_cache *vma,
-						const uint8_t *load_base,
 						size_t size, uint32_t flags)
 {
 	unsigned int i;
+	const void *region_addr;
 	int ret;
-	const elf_shdr_t *shdr;
 
 	ret = llext_manager_align_map(vma, size, SYS_MM_MEM_PERM_RW);
 	if (ret < 0) {
 		tr_err(&lib_manager_tr, "cannot map %u of %p", size, (__sparse_force void *)vma);
 		return ret;
 	}
 
-	size_t init_offset = 0;
+	llext_get_region_info(ldr, ext, region, NULL, &region_addr, NULL);
 
 	/* Need to copy sections within regions individually, offsets may differ */
-	for (i = 0, shdr = llext_section_headers(ext); i < llext_section_count(ext); i++, shdr++) {
-		if ((uintptr_t)shdr->sh_addr < (uintptr_t)vma ||
-		    (uintptr_t)shdr->sh_addr >= (uintptr_t)vma + size)
-			continue;
+	for (i = 0; i < llext_section_count(ext); i++) {
+		const elf_shdr_t *shdr;
+		enum llext_mem s_region = LLEXT_MEM_COUNT;
+		size_t s_offset = 0;
 
-		if (!init_offset)
-			init_offset = shdr->sh_offset;
+		llext_get_section_info(ldr, ext, i, &shdr, &s_region, &s_offset);
 
-		/* found a section within the region */
-		size_t offset = shdr->sh_offset - init_offset;
+		if (s_region != region)
+			continue;
 
-		ret = memcpy_s((__sparse_force void *)shdr->sh_addr, size - offset,
-			       load_base + offset, shdr->sh_size);
+		ret = memcpy_s((__sparse_force void *)shdr->sh_addr, size - s_offset,
+			       (const uint8_t *)region_addr + s_offset, shdr->sh_size);
 		if (ret < 0)
 			return ret;
 	}
@@ -120,6 +121,10 @@ static int llext_manager_load_data_from_storage(const struct llext *ext,
 static int llext_manager_load_module(const struct llext *ext, const struct llext_loader *ldr,
 				     const struct lib_manager_module *mctx)
 {
+	const elf_shdr_t *bss_hdr;
+
+	llext_get_region_info(ldr, ext, LLEXT_MEM_BSS, &bss_hdr, NULL, NULL);
+
 	/* Executable code (.text) */
 	void __sparse_cache *va_base_text = (void __sparse_cache *)
 		mctx->segment[LIB_MANAGER_TEXT].addr;
@@ -137,8 +142,8 @@ static int llext_manager_load_module(const struct llext *ext, const struct llext
 
 	/* .bss, should be within writable data above */
 	void __sparse_cache *bss_addr = (void __sparse_cache *)
-		ldr->sects[LLEXT_MEM_BSS].sh_addr;
-	size_t bss_size = ldr->sects[LLEXT_MEM_BSS].sh_size;
+		bss_hdr->sh_addr;
+	size_t bss_size = bss_hdr->sh_size;
 	int ret;
 
 	/* Check, that .bss is within .data */
@@ -151,7 +156,7 @@ static int llext_manager_load_module(const struct llext *ext, const struct llext
 			va_base_data = bss_addr;
 			data_size += bss_size;
 		} else if ((uintptr_t)bss_addr == (uintptr_t)va_base_data +
-			   ALIGN_UP(data_size, ldr->sects[LLEXT_MEM_BSS].sh_addralign)) {
+			   ALIGN_UP(data_size, bss_hdr->sh_addralign)) {
 			/* .bss directly behind writable data, append */
 			data_size += bss_size;
 		} else {
@@ -163,20 +168,20 @@ static int llext_manager_load_module(const struct llext *ext, const struct llext
 	}
 
 	/* Copy Code */
-	ret = llext_manager_load_data_from_storage(ext, va_base_text, ext->mem[LLEXT_MEM_TEXT],
-						   text_size, SYS_MM_MEM_PERM_EXEC);
+	ret = llext_manager_load_data_from_storage(ldr, ext, LLEXT_MEM_TEXT,
+						   va_base_text, text_size, SYS_MM_MEM_PERM_EXEC);
 	if (ret < 0)
 		return ret;
 
 	/* Copy read-only data */
-	ret = llext_manager_load_data_from_storage(ext, va_base_rodata, ext->mem[LLEXT_MEM_RODATA],
-						   rodata_size, 0);
+	ret = llext_manager_load_data_from_storage(ldr, ext, LLEXT_MEM_RODATA,
+						   va_base_rodata, rodata_size, 0);
 	if (ret < 0)
 		goto e_text;
 
 	/* Copy writable data */
-	ret = llext_manager_load_data_from_storage(ext, va_base_data, ext->mem[LLEXT_MEM_DATA],
-						   data_size, SYS_MM_MEM_PERM_RW);
+	ret = llext_manager_load_data_from_storage(ldr, ext, LLEXT_MEM_DATA,
+						   va_base_data, data_size, SYS_MM_MEM_PERM_RW);
 	if (ret < 0)
 		goto e_rodata;
 
@@ -240,49 +245,55 @@ static int llext_manager_link(struct llext_loader *ldr, const char *name,
 		.relocate_local = !mctx->segment[LIB_MANAGER_TEXT].size,
 		.pre_located = true,
 		.section_detached = llext_manager_section_detached,
+		.keep_section_info = true,
 	};
+	const elf_shdr_t *hdr;
 	int ret;
 
 	ret = llext_load(ldr, name, llext, &ldr_parm);
 	if (ret)
 		return ret;
 
-	mctx->segment[LIB_MANAGER_TEXT].addr = ldr->sects[LLEXT_MEM_TEXT].sh_addr;
-	mctx->segment[LIB_MANAGER_TEXT].size = ldr->sects[LLEXT_MEM_TEXT].sh_size;
+	/* All code sections */
+	llext_get_region_info(ldr, *llext, LLEXT_MEM_TEXT, &hdr, NULL, NULL);
+	mctx->segment[LIB_MANAGER_TEXT].addr = hdr->sh_addr;
+	mctx->segment[LIB_MANAGER_TEXT].size = hdr->sh_size;
 
 	tr_dbg(&lib_manager_tr, ".text: start: %#lx size %#x",
 	       mctx->segment[LIB_MANAGER_TEXT].addr,
 	       mctx->segment[LIB_MANAGER_TEXT].size);
 
 	/* All read-only data sections */
-	mctx->segment[LIB_MANAGER_RODATA].addr =
-		ldr->sects[LLEXT_MEM_RODATA].sh_addr;
-	mctx->segment[LIB_MANAGER_RODATA].size = ldr->sects[LLEXT_MEM_RODATA].sh_size;
+	llext_get_region_info(ldr, *llext, LLEXT_MEM_RODATA, &hdr, NULL, NULL);
+	mctx->segment[LIB_MANAGER_RODATA].addr = hdr->sh_addr;
+	mctx->segment[LIB_MANAGER_RODATA].size = hdr->sh_size;
 
 	tr_dbg(&lib_manager_tr, ".rodata: start: %#lx size %#x",
 	       mctx->segment[LIB_MANAGER_RODATA].addr,
 	       mctx->segment[LIB_MANAGER_RODATA].size);
 
 	/* All writable data sections */
-	mctx->segment[LIB_MANAGER_DATA].addr =
-		ldr->sects[LLEXT_MEM_DATA].sh_addr;
-	mctx->segment[LIB_MANAGER_DATA].size = ldr->sects[LLEXT_MEM_DATA].sh_size;
+	llext_get_region_info(ldr, *llext, LLEXT_MEM_DATA, &hdr, NULL, NULL);
+	mctx->segment[LIB_MANAGER_DATA].addr = hdr->sh_addr;
+	mctx->segment[LIB_MANAGER_DATA].size = hdr->sh_size;
 
 	tr_dbg(&lib_manager_tr, ".data: start: %#lx size %#x",
 	       mctx->segment[LIB_MANAGER_DATA].addr,
 	       mctx->segment[LIB_MANAGER_DATA].size);
 
 	*buildinfo = NULL;
-	ssize_t binfo_o = llext_find_section(ldr, ".mod_buildinfo");
-
-	if (binfo_o >= 0)
-		*buildinfo = llext_peek(ldr, binfo_o);
+	ret = llext_section_shndx(ldr, *llext, ".mod_buildinfo");
+	if (ret >= 0) {
+		llext_get_section_info(ldr, *llext, ret, &hdr, NULL, NULL);
+		*buildinfo = llext_peek(ldr, hdr->sh_offset);
+	}
 
 	*mod_manifest = NULL;
-	ssize_t mod_o = llext_find_section(ldr, ".module");
-
-	if (mod_o >= 0)
-		*mod_manifest = llext_peek(ldr, mod_o);
+	ret = llext_section_shndx(ldr, *llext, ".module");
+	if (ret >= 0) {
+		llext_get_section_info(ldr, *llext, ret, &hdr, NULL, NULL);
+		*mod_manifest = llext_peek(ldr, hdr->sh_offset);
+	}
 
 	return *buildinfo && *mod_manifest ? 0 : -EPROTO;
 }