util/cbfstool/rmodule.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #ifndef TOOL_RMODULE_H
   4 #define TOOL_RMODULE_H
   5
   6 #include "elfparsing.h"
   7 #include "common.h"
   8
   9 struct arch_ops {
  10         int arch;
  11         /* Determine if relocation is a valid type for the architecture. */
  12         int (*valid_type)(Elf64_Rela *rel);
  13         /* Determine if relocation should be emitted. */
  14         int (*should_emit)(Elf64_Rela *rel);
  15 };
  16
  17 /*
  18  * The fields in rmod_context are read-only to the user. These are
  19  * exposed for easy shareability.
  20  */
  21 struct rmod_context {
  22         /* Ops to process relocations. */
  23         const struct arch_ops *ops;
  24
  25         /* endian conversion ops */
  26         struct xdr *xdr;
  27
  28         /* Parsed ELF structure. */
  29         struct parsed_elf pelf;
  30         /* Program segment. */
  31         Elf64_Phdr *phdr;
  32         /* Symbol string table. */
  33         char *strtab;
  34
  35         /* Collection of relocation addresses fixup in the module. */
  36         Elf64_Xword nrelocs;
  37         Elf64_Addr *emitted_relocs;
  38
  39         /* The following fields are addresses within the linked program.  */
  40         Elf64_Addr parameters_begin;
  41         Elf64_Addr parameters_end;
  42         Elf64_Addr bss_begin;
  43         Elf64_Addr bss_end;
  44 };
  45
  46 struct reloc_filter {
  47         /* Return < 0 on error. 0 to ignore relocation and 1 to include
  48          * relocation. */
  49         int (*filter)(struct reloc_filter *f, const Elf64_Rela *r);
  50         /* Pointer for filter provides */
  51         void *context;
  52 };
  53
  54 /*
  55  * Parse an ELF file within the elfin buffer and fill in the elfout buffer
  56  * with a created rmodule in ELF format. Return 0 on success, < 0 on error.
  57  */
  58 int rmodule_create(const struct buffer *elfin, struct buffer *elfout);
  59
  60 /*
  61  * Initialize an rmodule context from an ELF buffer. Returns 0 on scucess, < 0
  62  * on error.
  63  */
  64 int rmodule_init(struct rmod_context *ctx, const struct buffer *elfin);
  65
  66 /*
  67  * Collect all the relocations that apply to the program in
  68  * nrelocs/emitted_relocs. One can optionally provide a reloc_filter object
  69  * to help in relocation filtering. The filter function will be called twice:
  70  * once for counting and once for emitting. The same response should be
  71  * provided for each call. Returns 0 on success, < 0 on error.
  72  */
  73 int rmodule_collect_relocations(struct rmod_context *c, struct reloc_filter *f);
  74
  75 /* Clean up the memory consumed by the rmodule context. */
  76 void rmodule_cleanup(struct rmod_context *ctx);
  77
  78 /*
  79  * Create an ELF file from the passed in rmodule in the buffer. The buffer
  80  * contents will be replaced with an ELF file. Returns 1 if buff doesn't
  81  * contain an rmodule and < 0 on failure, 0 on success.
  82  */
  83 int rmodule_stage_to_elf(Elf64_Ehdr *ehdr, struct buffer *buff);
  84
  85 #endif /* TOOL_RMODULE_H */