Modules: Move first five of many C files from sched/module to libc/modlib

2026-09-24 00:42:03 +08:00 · 2017-01-29 10:05:15 -06:00
parent 00e46b5966
commit 5e94dd22bb
22 changed files with 241 additions and 250 deletions
@@ -0,0 +1,304 @@
+/****************************************************************************
+ * libc/modlib/modlib_bind.c
+ *
+ *   Copyright (C) 2015, 2017 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <stdint.h>
+#include <string.h>
+#include <elf32.h>
+#include <errno.h>
+#include <assert.h>
+#include <debug.h>
+
+#include <nuttx/module.h>
+#include <nuttx/lib/modlib.h>
+#include <nuttx/binfmt/symtab.h>
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: modlib_readrel
+ *
+ * Description:
+ *   Read the ELF32_Rel structure into memory.
+ *
+ ****************************************************************************/
+
+static inline int modlib_readrel(FAR struct mod_loadinfo_s *loadinfo,
+                                 FAR const Elf32_Shdr *relsec,
+                                 int index, FAR Elf32_Rel *rel)
+{
+  off_t offset;
+
+  /* Verify that the symbol table index lies within symbol table */
+
+  if (index < 0 || index > (relsec->sh_size / sizeof(Elf32_Rel)))
+    {
+      serr("ERROR: Bad relocation symbol index: %d\n", index);
+      return -EINVAL;
+    }
+
+  /* Get the file offset to the symbol table entry */
+
+  offset = relsec->sh_offset + sizeof(Elf32_Rel) * index;
+
+  /* And, finally, read the symbol table entry into memory */
+
+  return mod_read(loadinfo, (FAR uint8_t *)rel, sizeof(Elf32_Rel), offset);
+}
+
+/****************************************************************************
+ * Name: modlib_relocate and modlib_relocateadd
+ *
+ * Description:
+ *   Perform all relocations associated with a section.
+ *
+ * Returned Value:
+ *   0 (OK) is returned on success and a negated errno is returned on
+ *   failure.
+ *
+ ****************************************************************************/
+
+static int modlib_relocate(FAR struct module_s *modp,
+                           FAR struct mod_loadinfo_s *loadinfo, int relidx)
+
+{
+  FAR Elf32_Shdr *relsec = &loadinfo->shdr[relidx];
+  FAR Elf32_Shdr *dstsec = &loadinfo->shdr[relsec->sh_info];
+  Elf32_Rel       rel;
+  Elf32_Sym       sym;
+  FAR Elf32_Sym  *psym;
+  uintptr_t       addr;
+  int             symidx;
+  int             ret;
+  int             i;
+
+  /* Examine each relocation in the section.  'relsec' is the section
+   * containing the relations.  'dstsec' is the section containing the data
+   * to be relocated.
+   */
+
+  for (i = 0; i < relsec->sh_size / sizeof(Elf32_Rel); i++)
+    {
+      psym = &sym;
+
+      /* Read the relocation entry into memory */
+
+      ret = modlib_readrel(loadinfo, relsec, i, &rel);
+      if (ret < 0)
+        {
+          serr("ERROR: Section %d reloc %d: Failed to read relocation entry: %d\n",
+               relidx, i, ret);
+          return ret;
+        }
+
+      /* Get the symbol table index for the relocation.  This is contained
+       * in a bit-field within the r_info element.
+       */
+
+      symidx = ELF32_R_SYM(rel.r_info);
+
+      /* Read the symbol table entry into memory */
+
+      ret = mod_readsym(loadinfo, symidx, &sym);
+      if (ret < 0)
+        {
+          serr("ERROR: Section %d reloc %d: Failed to read symbol[%d]: %d\n",
+               relidx, i, symidx, ret);
+          return ret;
+        }
+
+      /* Get the value of the symbol (in sym.st_value) */
+
+      ret = mod_symvalue(modp, loadinfo, &sym);
+      if (ret < 0)
+        {
+          /* The special error -ESRCH is returned only in one condition:  The
+           * symbol has no name.
+           *
+           * There are a few relocations for a few architectures that do
+           * no depend upon a named symbol.  We don't know if that is the
+           * case here, but we will use a NULL symbol pointer to indicate
+           * that case to up_relocate().  That function can then do what
+           * is best.
+           */
+
+          if (ret == -ESRCH)
+            {
+              serr("ERROR: Section %d reloc %d: Undefined symbol[%d] has no name: %d\n",
+                  relidx, i, symidx, ret);
+              psym = NULL;
+            }
+          else
+            {
+              serr("ERROR: Section %d reloc %d: Failed to get value of symbol[%d]: %d\n",
+                  relidx, i, symidx, ret);
+              return ret;
+            }
+        }
+
+      /* Calculate the relocation address. */
+
+      if (rel.r_offset < 0 || rel.r_offset > dstsec->sh_size - sizeof(uint32_t))
+        {
+          serr("ERROR: Section %d reloc %d: Relocation address out of range, offset %d size %d\n",
+               relidx, i, rel.r_offset, dstsec->sh_size);
+          return -EINVAL;
+        }
+
+      addr = dstsec->sh_addr + rel.r_offset;
+
+      /* Now perform the architecture-specific relocation */
+
+      ret = up_relocate(&rel, psym, addr);
+      if (ret < 0)
+        {
+          serr("ERROR: Section %d reloc %d: Relocation failed: %d\n", relidx, i, ret);
+          return ret;
+        }
+    }
+
+  return OK;
+}
+
+static int modlib_relocateadd(FAR struct module_s *modp,
+                           FAR struct mod_loadinfo_s *loadinfo, int relidx)
+{
+  serr("ERROR: Not implemented\n");
+  return -ENOSYS;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: modlib_bind
+ *
+ * Description:
+ *   Bind the imported symbol names in the loaded module described by
+ *   'loadinfo' using the exported symbol values provided by mod_setsymtab().
+ *
+ * Input Parameters:
+ *   modp     - Module state information
+ *   loadinfo - Load state information
+ *
+ * Returned Value:
+ *   0 (OK) is returned on success and a negated errno is returned on
+ *   failure.
+ *
+ ****************************************************************************/
+
+int modlib_bind(FAR struct module_s *modp, FAR struct mod_loadinfo_s *loadinfo)
+{
+  int ret;
+  int i;
+
+  /* Find the symbol and string tables */
+
+  ret = mod_findsymtab(loadinfo);
+  if (ret < 0)
+    {
+      return ret;
+    }
+
+  /* Allocate an I/O buffer.  This buffer is used by mod_symname() to
+   * accumulate the variable length symbol name.
+   */
+
+  ret = mod_allocbuffer(loadinfo);
+  if (ret < 0)
+    {
+      serr("ERROR: mod_allocbuffer failed: %d\n", ret);
+      return -ENOMEM;
+    }
+
+  /* Process relocations in every allocated section */
+
+  for (i = 1; i < loadinfo->ehdr.e_shnum; i++)
+    {
+      /* Get the index to the relocation section */
+
+      int infosec = loadinfo->shdr[i].sh_info;
+      if (infosec >= loadinfo->ehdr.e_shnum)
+        {
+          continue;
+        }
+
+      /* Make sure that the section is allocated.  We can't relocate
+       * sections that were not loaded into memory.
+       */
+
+      if ((loadinfo->shdr[infosec].sh_flags & SHF_ALLOC) == 0)
+        {
+          continue;
+        }
+
+      /* Process the relocations by type */
+
+      if (loadinfo->shdr[i].sh_type == SHT_REL)
+        {
+          ret = modlib_relocate(modp, loadinfo, i);
+        }
+      else if (loadinfo->shdr[i].sh_type == SHT_RELA)
+        {
+          ret = modlib_relocateadd(modp, loadinfo, i);
+        }
+
+      if (ret < 0)
+        {
+          break;
+        }
+    }
+
+#if defined(CONFIG_ARCH_HAVE_COHERENT_DCACHE)
+  /* Ensure that the I and D caches are coherent before starting the newly
+   * loaded module by cleaning the D cache (i.e., flushing the D cache
+   * contents to memory and invalidating the I cache).
+   */
+
+  up_coherent_dcache(loadinfo->textalloc, loadinfo->textsize);
+  up_coherent_dcache(loadinfo->datastart, loadinfo->datasize);
+
+#endif
+
+  return ret;
+}