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         /* Number of loadable segments. */
  33         size_t nsegments;
  34         /* Symbol string table. */
  35         char *strtab;
  36
  37         /* Collection of relocation addresses fixup in the module. */
  38         Elf64_Xword nrelocs;
  39         Elf64_Addr *emitted_relocs;
  40
  41         /* The following fields are addresses within the linked program.  */
  42         Elf64_Addr parameters_begin;
  43         Elf64_Addr parameters_end;
  44         Elf64_Addr bss_begin;
  45         Elf64_Addr bss_end;
  46 };
  47
  48 struct reloc_filter {
  49         /* Return < 0 on error. 0 to ignore relocation and 1 to include
  50          * relocation. */
  51         int (*filter)(struct reloc_filter *f, const Elf64_Rela *r);
  52         /* Pointer for filter provides */
  53         void *context;
  54 };
  55
  56 /*
  57  * Parse an ELF file within the elfin buffer and fill in the elfout buffer
  58  * with a created rmodule in ELF format. Return 0 on success, < 0 on error.
  59  */
  60 int rmodule_create(const struct buffer *elfin, struct buffer *elfout);
  61
  62 /*
  63  * Initialize an rmodule context from an ELF buffer. Returns 0 on scucess, < 0
  64  * on error.
  65  */
  66 int rmodule_init(struct rmod_context *ctx, const struct buffer *elfin);
  67
  68 /*
  69  * Collect all the relocations that apply to the program in
  70  * nrelocs/emitted_relocs. One can optionally provide a reloc_filter object
  71  * to help in relocation filtering. The filter function will be called twice:
  72  * once for counting and once for emitting. The same response should be
  73  * provided for each call. Returns 0 on success, < 0 on error.
  74  */
  75 int rmodule_collect_relocations(struct rmod_context *c, struct reloc_filter *f);
  76
  77 /* Clean up the memory consumed by the rmodule context. */
  78 void rmodule_cleanup(struct rmod_context *ctx);
  79
  80 /*
  81  * Create an ELF file from the passed in rmodule in the buffer. The buffer
  82  * contents will be replaced with an ELF file. Returns 1 if buff doesn't
  83  * contain an rmodule and < 0 on failure, 0 on success.
  84  */
  85 int rmodule_stage_to_elf(Elf64_Ehdr *ehdr, struct buffer *buff);
  86
  87 #endif /* TOOL_RMODULE_H */