modules: add elf_obj linker for amd64
authorSimon Schubert <corecode@dragonflybsd.org>
Thu, 3 Sep 2009 21:58:17 +0000 (23:58 +0200)
committerSimon Schubert <corecode@dragonflybsd.org>
Thu, 3 Sep 2009 23:17:44 +0000 (01:17 +0200)
Obtained-from:  FreeBSD

sys/kern/link_elf_obj.c [new file with mode: 0644]
sys/platform/pc64/conf/files

diff --git a/sys/kern/link_elf_obj.c b/sys/kern/link_elf_obj.c
new file mode 100644 (file)
index 0000000..fbc9e9f
--- /dev/null
@@ -0,0 +1,1267 @@
+/*-
+ * Copyright (c) 1998 Doug Rabson
+ * Copyright (c) 2004 Peter Wemm
+ * All rights reserved.
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
+ *
+ * $FreeBSD: src/sys/kern/link_elf.c,v 1.24 1999/12/24 15:33:36 bde Exp $
+ * $DragonFly: src/sys/kern/link_elf.c,v 1.29 2008/08/01 23:11:16 dillon Exp $
+ */
+
+#include <sys/param.h>
+#include <sys/kernel.h>
+#include <sys/systm.h>
+#include <sys/malloc.h>
+#include <sys/proc.h>
+#include <sys/nlookup.h>
+#include <sys/fcntl.h>
+#include <sys/vnode.h>
+#include <sys/linker.h>
+#include <machine/elf.h>
+
+#include <vm/vm.h>
+#include <vm/vm_param.h>
+#include <vm/vm_zone.h>
+#include <vm/vm_object.h>
+#include <vm/vm_kern.h>
+#include <vm/vm_extern.h>
+#include <sys/lock.h>
+#include <vm/pmap.h>
+#include <vm/vm_map.h>
+
+static int     link_elf_obj_preload_file(const char *, linker_file_t *);
+static int     link_elf_obj_preload_finish(linker_file_t);
+static int     link_elf_obj_load_file(const char *, linker_file_t *);
+static int
+link_elf_obj_lookup_symbol(linker_file_t, const char *,
+                      c_linker_sym_t *);
+static int     link_elf_obj_symbol_values(linker_file_t, c_linker_sym_t, linker_symval_t *);
+static int
+link_elf_obj_search_symbol(linker_file_t, caddr_t value,
+                      c_linker_sym_t * sym, long *diffp);
+
+static void    link_elf_obj_unload_file(linker_file_t);
+static int
+link_elf_obj_lookup_set(linker_file_t, const char *,
+                   void ***, void ***, int *);
+static void    link_elf_obj_reloc_local(linker_file_t lf);
+static int elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *);
+
+static struct linker_class_ops link_elf_obj_class_ops = {
+       link_elf_obj_load_file,
+       link_elf_obj_preload_file,
+};
+
+static struct linker_file_ops link_elf_obj_file_ops = {
+       .lookup_symbol = link_elf_obj_lookup_symbol,
+       .symbol_values = link_elf_obj_symbol_values,
+       .search_symbol = link_elf_obj_search_symbol,
+       .preload_finish = link_elf_obj_preload_finish,
+       .unload = link_elf_obj_unload_file,
+       .lookup_set = link_elf_obj_lookup_set,
+};
+
+typedef struct {
+       void           *addr;
+       Elf_Off         size;
+       int             flags;
+       int             sec;            /* Original section */
+       char           *name;
+}              Elf_progent;
+
+typedef struct {
+       Elf_Rel        *rel;
+       int             nrel;
+       int             sec;
+}              Elf_relent;
+
+typedef struct {
+       Elf_Rela       *rela;
+       int             nrela;
+       int             sec;
+}              Elf_relaent;
+
+
+typedef struct elf_file {
+       int             preloaded;
+
+       caddr_t         address;        /* Relocation address */
+       vm_object_t     object;         /* VM object to hold file pages */
+       Elf_Shdr       *e_shdr;
+
+       Elf_progent    *progtab;
+       int             nprogtab;
+
+       Elf_relaent    *relatab;
+       int             nrelatab;
+
+       Elf_relent     *reltab;
+       int             nreltab;
+
+       Elf_Sym        *ddbsymtab;      /* The symbol table we are using */
+       long            ddbsymcnt;      /* Number of symbols */
+       caddr_t         ddbstrtab;      /* String table */
+       long            ddbstrcnt;      /* number of bytes in string table */
+
+       caddr_t         shstrtab;       /* Section name string table */
+       long            shstrcnt;       /* number of bytes in string table */
+
+       caddr_t         ctftab;         /* CTF table */
+       long            ctfcnt;         /* number of bytes in CTF table */
+       caddr_t         ctfoff;         /* CTF offset table */
+       caddr_t         typoff;         /* Type offset table */
+       long            typlen;         /* Number of type entries. */
+
+}              *elf_file_t;
+
+static int     relocate_file(linker_file_t lf);
+
+/*
+ * The kernel symbol table starts here.
+ */
+extern struct _dynamic _DYNAMIC;
+
+static void
+link_elf_obj_init(void *arg)
+{
+#if ELF_TARG_CLASS == ELFCLASS32
+       linker_add_class("elf32", NULL, &link_elf_obj_class_ops);
+#else
+       linker_add_class("elf64", NULL, &link_elf_obj_class_ops);
+#endif
+}
+
+SYSINIT(link_elf, SI_BOOT2_KLD, SI_ORDER_SECOND, link_elf_obj_init, 0);
+
+static void
+link_elf_obj_error(const char *file, const char *s)
+{
+       kprintf("kldload: %s: %s\n", file, s);
+}
+
+static int
+link_elf_obj_preload_file(const char *filename, linker_file_t *result)
+{
+       Elf_Ehdr       *hdr;
+       Elf_Shdr       *shdr;
+       Elf_Sym *es;
+       caddr_t         modptr, baseptr, sizeptr;
+       char           *type;
+       elf_file_t      ef;
+       linker_file_t   lf;
+       Elf_Addr        off;
+       int             error, i, j, pb, ra, rl, shstrindex, symstrindex, symtabindex;
+
+       /*
+        * Look to see if we have the module preloaded.
+        */
+       modptr = preload_search_by_name(filename);
+       if (modptr == NULL)
+               return ENOENT;
+
+       /* It's preloaded, check we can handle it and collect information */
+       type = (char *)preload_search_info(modptr, MODINFO_TYPE);
+       baseptr = preload_search_info(modptr, MODINFO_ADDR);
+       sizeptr = preload_search_info(modptr, MODINFO_SIZE);
+       hdr = (Elf_Ehdr *) preload_search_info(modptr, MODINFO_METADATA |
+                                              MODINFOMD_ELFHDR);
+       shdr = (Elf_Shdr *) preload_search_info(modptr, MODINFO_METADATA |
+                                               MODINFOMD_SHDR);
+       if (type == NULL ||
+           (strcmp(type, "elf" __XSTRING(__ELF_WORD_SIZE) " obj module") != 0 &&
+            strcmp(type, "elf obj module") != 0)) {
+               return (EFTYPE);
+       }
+       if (baseptr == NULL || sizeptr == NULL || hdr == NULL || shdr == NULL)
+               return (EINVAL);
+
+       ef = kmalloc(sizeof(struct elf_file), M_LINKER, M_WAITOK | M_ZERO);
+       ef->preloaded = 1;
+       ef->address = *(caddr_t *) baseptr;
+       lf = linker_make_file(filename, ef, &link_elf_obj_file_ops);
+       if (lf == NULL) {
+               kfree(ef, M_LINKER);
+               return ENOMEM;
+       }
+       lf->address = ef->address;
+       lf->size = *(size_t *) sizeptr;
+
+       if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS ||
+           hdr->e_ident[EI_DATA] != ELF_TARG_DATA ||
+           hdr->e_ident[EI_VERSION] != EV_CURRENT ||
+           hdr->e_version != EV_CURRENT ||
+           hdr->e_type != ET_REL ||
+           hdr->e_machine != ELF_TARG_MACH) {
+               error = EFTYPE;
+               goto out;
+       }
+       ef->e_shdr = shdr;
+
+       /* Scan the section header for information and table sizing. */
+       symtabindex = -1;
+       symstrindex = -1;
+       for (i = 0; i < hdr->e_shnum; i++) {
+               switch (shdr[i].sh_type) {
+               case SHT_PROGBITS:
+               case SHT_NOBITS:
+                       ef->nprogtab++;
+                       break;
+               case SHT_SYMTAB:
+                       symtabindex = i;
+                       symstrindex = shdr[i].sh_link;
+                       break;
+               case SHT_REL:
+                       ef->nreltab++;
+                       break;
+               case SHT_RELA:
+                       ef->nrelatab++;
+                       break;
+               }
+       }
+
+       shstrindex = hdr->e_shstrndx;
+       if (ef->nprogtab == 0 || symstrindex < 0 ||
+           symstrindex >= hdr->e_shnum ||
+           shdr[symstrindex].sh_type != SHT_STRTAB || shstrindex == 0 ||
+           shstrindex >= hdr->e_shnum ||
+           shdr[shstrindex].sh_type != SHT_STRTAB) {
+               error = ENOEXEC;
+               goto out;
+       }
+       /* Allocate space for tracking the load chunks */
+       if (ef->nprogtab != 0)
+               ef->progtab = kmalloc(ef->nprogtab * sizeof(*ef->progtab),
+                                    M_LINKER, M_WAITOK | M_ZERO);
+       if (ef->nreltab != 0)
+               ef->reltab = kmalloc(ef->nreltab * sizeof(*ef->reltab),
+                                   M_LINKER, M_WAITOK | M_ZERO);
+       if (ef->nrelatab != 0)
+               ef->relatab = kmalloc(ef->nrelatab * sizeof(*ef->relatab),
+                                    M_LINKER, M_WAITOK | M_ZERO);
+       if ((ef->nprogtab != 0 && ef->progtab == NULL) ||
+           (ef->nreltab != 0 && ef->reltab == NULL) ||
+           (ef->nrelatab != 0 && ef->relatab == NULL)) {
+               error = ENOMEM;
+               goto out;
+       }
+       /* XXX, relocate the sh_addr fields saved by the loader. */
+       off = 0;
+       for (i = 0; i < hdr->e_shnum; i++) {
+               if (shdr[i].sh_addr != 0 && (off == 0 || shdr[i].sh_addr < off))
+                       off = shdr[i].sh_addr;
+       }
+       for (i = 0; i < hdr->e_shnum; i++) {
+               if (shdr[i].sh_addr != 0)
+                       shdr[i].sh_addr = shdr[i].sh_addr - off +
+                               (Elf_Addr) ef->address;
+       }
+
+       ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym);
+       ef->ddbsymtab = (Elf_Sym *) shdr[symtabindex].sh_addr;
+       ef->ddbstrcnt = shdr[symstrindex].sh_size;
+       ef->ddbstrtab = (char *)shdr[symstrindex].sh_addr;
+       ef->shstrcnt = shdr[shstrindex].sh_size;
+       ef->shstrtab = (char *)shdr[shstrindex].sh_addr;
+
+       /* Now fill out progtab and the relocation tables. */
+       pb = 0;
+       rl = 0;
+       ra = 0;
+       for (i = 0; i < hdr->e_shnum; i++) {
+               switch (shdr[i].sh_type) {
+               case SHT_PROGBITS:
+               case SHT_NOBITS:
+                       ef->progtab[pb].addr = (void *)shdr[i].sh_addr;
+                       if (shdr[i].sh_type == SHT_PROGBITS)
+                               ef->progtab[pb].name = "<<PROGBITS>>";
+                       else
+                               ef->progtab[pb].name = "<<NOBITS>>";
+                       ef->progtab[pb].size = shdr[i].sh_size;
+                       ef->progtab[pb].sec = i;
+                       if (ef->shstrtab && shdr[i].sh_name != 0)
+                               ef->progtab[pb].name =
+                                       ef->shstrtab + shdr[i].sh_name;
+#if 0
+                       if (ef->progtab[pb].name != NULL &&
+                           !strcmp(ef->progtab[pb].name, "set_pcpu")) {
+                               void           *dpcpu;
+
+                               dpcpu = dpcpu_alloc(shdr[i].sh_size);
+                               if (dpcpu == NULL) {
+                                       error = ENOSPC;
+                                       goto out;
+                               }
+                               memcpy(dpcpu, ef->progtab[pb].addr,
+                                      ef->progtab[pb].size);
+                               dpcpu_copy(dpcpu, shdr[i].sh_size);
+                               ef->progtab[pb].addr = dpcpu;
+#ifdef VIMAGE
+                       } else if (ef->progtab[pb].name != NULL &&
+                                  !strcmp(ef->progtab[pb].name, VNET_SETNAME)) {
+                               void           *vnet_data;
+
+                               vnet_data = vnet_data_alloc(shdr[i].sh_size);
+                               if (vnet_data == NULL) {
+                                       error = ENOSPC;
+                                       goto out;
+                               }
+                               memcpy(vnet_data, ef->progtab[pb].addr,
+                                      ef->progtab[pb].size);
+                               vnet_data_copy(vnet_data, shdr[i].sh_size);
+                               ef->progtab[pb].addr = vnet_data;
+#endif
+                       }
+#endif
+                       /* Update all symbol values with the offset. */
+                       for (j = 0; j < ef->ddbsymcnt; j++) {
+                               es = &ef->ddbsymtab[j];
+                               if (es->st_shndx != i)
+                                       continue;
+                               es->st_value += (Elf_Addr) ef->progtab[pb].addr;
+                       }
+                       pb++;
+                       break;
+               case SHT_REL:
+                       ef->reltab[rl].rel = (Elf_Rel *) shdr[i].sh_addr;
+                       ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel);
+                       ef->reltab[rl].sec = shdr[i].sh_info;
+                       rl++;
+                       break;
+               case SHT_RELA:
+                       ef->relatab[ra].rela = (Elf_Rela *) shdr[i].sh_addr;
+                       ef->relatab[ra].nrela =
+                               shdr[i].sh_size / sizeof(Elf_Rela);
+                       ef->relatab[ra].sec = shdr[i].sh_info;
+                       ra++;
+                       break;
+               }
+       }
+       if (pb != ef->nprogtab)
+               panic("lost progbits");
+       if (rl != ef->nreltab)
+               panic("lost reltab");
+       if (ra != ef->nrelatab)
+               panic("lost relatab");
+
+       /* Local intra-module relocations */
+       link_elf_obj_reloc_local(lf);
+
+       *result = lf;
+       return (0);
+
+out:
+       /* preload not done this way */
+       linker_file_unload(lf /* , LINKER_UNLOAD_FORCE */ );
+       return (error);
+}
+
+static int
+link_elf_obj_preload_finish(linker_file_t lf)
+{
+       int error;
+
+       error = relocate_file(lf);
+
+       return (error);
+}
+
+static int
+link_elf_obj_load_file(const char *filename, linker_file_t * result)
+{
+       struct nlookupdata nd;
+       struct thread  *td = curthread; /* XXX */
+       struct proc    *p = td->td_proc;
+       char           *pathname;
+       struct vnode   *vp;
+       Elf_Ehdr       *hdr;
+       Elf_Shdr       *shdr;
+       Elf_Sym        *es;
+       int             nbytes, i, j;
+       vm_offset_t     mapbase;
+       size_t          mapsize;
+       int             error = 0;
+       int             resid;
+       elf_file_t      ef;
+       linker_file_t   lf;
+       int             symtabindex;
+       int             symstrindex;
+       int             shstrindex;
+       int             nsym;
+       int             pb, rl, ra;
+       int             alignmask;
+
+       KKASSERT(p != NULL);
+       if (p->p_ucred == NULL) {
+               kprintf("link_elf_obj_load_file: cannot load '%s' from filesystem"
+                       " this early\n", filename);
+               return ENOENT;
+       }
+       shdr = NULL;
+       lf = NULL;
+       mapsize = 0;
+       hdr = NULL;
+       pathname = linker_search_path(filename);
+       if (pathname == NULL)
+               return ENOENT;
+
+       error = nlookup_init(&nd, pathname, UIO_SYSSPACE, NLC_FOLLOW | NLC_LOCKVP);
+       if (error == 0)
+               error = vn_open(&nd, NULL, FREAD, 0);
+       kfree(pathname, M_LINKER);
+       if (error) {
+               nlookup_done(&nd);
+               return error;
+       }
+       vp = nd.nl_open_vp;
+       nd.nl_open_vp = NULL;
+       nlookup_done(&nd);
+
+       /*
+        * Read the elf header from the file.
+        */
+       hdr = kmalloc(sizeof(*hdr), M_LINKER, M_WAITOK);
+       if (hdr == NULL) {
+               error = ENOMEM;
+               goto out;
+       }
+       error = vn_rdwr(UIO_READ, vp, (void *)hdr, sizeof(*hdr), 0,
+                       UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
+       if (error)
+               goto out;
+       if (resid != 0) {
+               error = ENOEXEC;
+               goto out;
+       }
+       if (!IS_ELF(*hdr)) {
+               error = ENOEXEC;
+               goto out;
+       }
+
+       if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS
+           || hdr->e_ident[EI_DATA] != ELF_TARG_DATA) {
+               link_elf_obj_error(filename, "Unsupported file layout");
+               error = ENOEXEC;
+               goto out;
+       }
+       if (hdr->e_ident[EI_VERSION] != EV_CURRENT
+           || hdr->e_version != EV_CURRENT) {
+               link_elf_obj_error(filename, "Unsupported file version");
+               error = ENOEXEC;
+               goto out;
+       }
+       if (hdr->e_type != ET_REL) {
+               error = ENOSYS;
+               goto out;
+       }
+       if (hdr->e_machine != ELF_TARG_MACH) {
+               link_elf_obj_error(filename, "Unsupported machine");
+               error = ENOEXEC;
+               goto out;
+       }
+
+       ef = kmalloc(sizeof(struct elf_file), M_LINKER, M_WAITOK | M_ZERO);
+       lf = linker_make_file(filename, ef, &link_elf_obj_file_ops);
+       if (lf == NULL) {
+               kfree(ef, M_LINKER);
+               error = ENOMEM;
+               goto out;
+       }
+       ef->nprogtab = 0;
+       ef->e_shdr = 0;
+       ef->nreltab = 0;
+       ef->nrelatab = 0;
+
+       /* Allocate and read in the section header */
+       nbytes = hdr->e_shnum * hdr->e_shentsize;
+       if (nbytes == 0 || hdr->e_shoff == 0 ||
+           hdr->e_shentsize != sizeof(Elf_Shdr)) {
+               error = ENOEXEC;
+               goto out;
+       }
+       shdr = kmalloc(nbytes, M_LINKER, M_WAITOK);
+       if (shdr == NULL) {
+               error = ENOMEM;
+               goto out;
+       }
+       ef->e_shdr = shdr;
+       error = vn_rdwr(UIO_READ, vp, (caddr_t) shdr, nbytes, hdr->e_shoff,
+                       UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
+       if (error)
+               goto out;
+       if (resid) {
+               error = ENOEXEC;
+               goto out;
+       }
+       /* Scan the section header for information and table sizing. */
+       nsym = 0;
+       symtabindex = -1;
+       symstrindex = -1;
+       for (i = 0; i < hdr->e_shnum; i++) {
+               switch (shdr[i].sh_type) {
+               case SHT_PROGBITS:
+               case SHT_NOBITS:
+                       ef->nprogtab++;
+                       break;
+               case SHT_SYMTAB:
+                       nsym++;
+                       symtabindex = i;
+                       symstrindex = shdr[i].sh_link;
+                       break;
+               case SHT_REL:
+                       ef->nreltab++;
+                       break;
+               case SHT_RELA:
+                       ef->nrelatab++;
+                       break;
+               case SHT_STRTAB:
+                       break;
+               }
+       }
+       if (ef->nprogtab == 0) {
+               link_elf_obj_error(filename, "file has no contents");
+               error = ENOEXEC;
+               goto out;
+       }
+       if (nsym != 1) {
+               /* Only allow one symbol table for now */
+               link_elf_obj_error(filename, "file has no valid symbol table");
+               error = ENOEXEC;
+               goto out;
+       }
+       if (symstrindex < 0 || symstrindex > hdr->e_shnum ||
+           shdr[symstrindex].sh_type != SHT_STRTAB) {
+               link_elf_obj_error(filename, "file has invalid symbol strings");
+               error = ENOEXEC;
+               goto out;
+       }
+       /* Allocate space for tracking the load chunks */
+       if (ef->nprogtab != 0)
+               ef->progtab = kmalloc(ef->nprogtab * sizeof(*ef->progtab),
+                                     M_LINKER, M_WAITOK | M_ZERO);
+       if (ef->nreltab != 0)
+               ef->reltab = kmalloc(ef->nreltab * sizeof(*ef->reltab),
+                                    M_LINKER, M_WAITOK | M_ZERO);
+       if (ef->nrelatab != 0)
+               ef->relatab = kmalloc(ef->nrelatab * sizeof(*ef->relatab),
+                                     M_LINKER, M_WAITOK | M_ZERO);
+       if ((ef->nprogtab != 0 && ef->progtab == NULL) ||
+           (ef->nreltab != 0 && ef->reltab == NULL) ||
+           (ef->nrelatab != 0 && ef->relatab == NULL)) {
+               error = ENOMEM;
+               goto out;
+       }
+       if (symtabindex == -1)
+               panic("lost symbol table index");
+       /* Allocate space for and load the symbol table */
+       ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym);
+       ef->ddbsymtab = kmalloc(shdr[symtabindex].sh_size, M_LINKER, M_WAITOK);
+       if (ef->ddbsymtab == NULL) {
+               error = ENOMEM;
+               goto out;
+       }
+       error = vn_rdwr(UIO_READ, vp, (void *)ef->ddbsymtab,
+                       shdr[symtabindex].sh_size, shdr[symtabindex].sh_offset,
+                       UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
+       if (error)
+               goto out;
+       if (resid != 0) {
+               error = EINVAL;
+               goto out;
+       }
+       if (symstrindex == -1)
+               panic("lost symbol string index");
+       /* Allocate space for and load the symbol strings */
+       ef->ddbstrcnt = shdr[symstrindex].sh_size;
+       ef->ddbstrtab = kmalloc(shdr[symstrindex].sh_size, M_LINKER, M_WAITOK);
+       if (ef->ddbstrtab == NULL) {
+               error = ENOMEM;
+               goto out;
+       }
+       error = vn_rdwr(UIO_READ, vp, ef->ddbstrtab,
+                       shdr[symstrindex].sh_size, shdr[symstrindex].sh_offset,
+                       UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
+       if (error)
+               goto out;
+       if (resid != 0) {
+               error = EINVAL;
+               goto out;
+       }
+       /* Do we have a string table for the section names?  */
+       shstrindex = -1;
+       if (hdr->e_shstrndx != 0 &&
+           shdr[hdr->e_shstrndx].sh_type == SHT_STRTAB) {
+               shstrindex = hdr->e_shstrndx;
+               ef->shstrcnt = shdr[shstrindex].sh_size;
+               ef->shstrtab = kmalloc(shdr[shstrindex].sh_size, M_LINKER,
+                                      M_WAITOK);
+               if (ef->shstrtab == NULL) {
+                       error = ENOMEM;
+                       goto out;
+               }
+               error = vn_rdwr(UIO_READ, vp, ef->shstrtab,
+                               shdr[shstrindex].sh_size, shdr[shstrindex].sh_offset,
+                               UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
+               if (error)
+                       goto out;
+               if (resid != 0) {
+                       error = EINVAL;
+                       goto out;
+               }
+       }
+       /* Size up code/data(progbits) and bss(nobits). */
+       alignmask = 0;
+       for (i = 0; i < hdr->e_shnum; i++) {
+               switch (shdr[i].sh_type) {
+               case SHT_PROGBITS:
+               case SHT_NOBITS:
+                       alignmask = shdr[i].sh_addralign - 1;
+                       mapsize += alignmask;
+                       mapsize &= ~alignmask;
+                       mapsize += shdr[i].sh_size;
+                       break;
+               }
+       }
+
+       /*
+        * We know how much space we need for the text/data/bss/etc. This
+        * stuff needs to be in a single chunk so that profiling etc can get
+        * the bounds and gdb can associate offsets with modules
+        */
+       ef->object = vm_object_allocate(OBJT_DEFAULT,
+                                       round_page(mapsize) >> PAGE_SHIFT);
+       if (ef->object == NULL) {
+               error = ENOMEM;
+               goto out;
+       }
+       ef->address = (caddr_t) vm_map_min(&kernel_map);
+
+       /*
+        * In order to satisfy amd64's architectural requirements on the
+        * location of code and data in the kernel's address space, request a
+        * mapping that is above the kernel.
+        */
+       mapbase = KERNBASE;
+       error = vm_map_find(&kernel_map, ef->object, 0, &mapbase,
+                           round_page(mapsize), TRUE, VM_MAPTYPE_NORMAL,
+                           VM_PROT_ALL, VM_PROT_ALL, FALSE);
+       if (error) {
+               vm_object_deallocate(ef->object);
+               ef->object = 0;
+               goto out;
+       }
+       /* Wire the pages */
+       error = vm_map_wire(&kernel_map, mapbase,
+                           mapbase + round_page(mapsize), 0);
+       if (error != KERN_SUCCESS) {
+               error = ENOMEM;
+               goto out;
+       }
+       /* Inform the kld system about the situation */
+       lf->address = ef->address = (caddr_t) mapbase;
+       lf->size = mapsize;
+
+       /*
+        * Now load code/data(progbits), zero bss(nobits), allocate space for
+        * and load relocs
+        */
+       pb = 0;
+       rl = 0;
+       ra = 0;
+       alignmask = 0;
+       for (i = 0; i < hdr->e_shnum; i++) {
+               switch (shdr[i].sh_type) {
+               case SHT_PROGBITS:
+               case SHT_NOBITS:
+                       alignmask = shdr[i].sh_addralign - 1;
+                       mapbase += alignmask;
+                       mapbase &= ~alignmask;
+                       if (ef->shstrtab && shdr[i].sh_name != 0)
+                               ef->progtab[pb].name =
+                                       ef->shstrtab + shdr[i].sh_name;
+                       else if (shdr[i].sh_type == SHT_PROGBITS)
+                               ef->progtab[pb].name = "<<PROGBITS>>";
+                       else
+                               ef->progtab[pb].name = "<<NOBITS>>";
+#if 0
+                       if (ef->progtab[pb].name != NULL &&
+                           !strcmp(ef->progtab[pb].name, "set_pcpu"))
+                               ef->progtab[pb].addr =
+                                       dpcpu_alloc(shdr[i].sh_size);
+#ifdef VIMAGE
+                       else if (ef->progtab[pb].name != NULL &&
+                                !strcmp(ef->progtab[pb].name, VNET_SETNAME))
+                               ef->progtab[pb].addr =
+                                       vnet_data_alloc(shdr[i].sh_size);
+#endif
+                       else
+#endif
+                               ef->progtab[pb].addr =
+                                       (void *)(uintptr_t) mapbase;
+                       if (ef->progtab[pb].addr == NULL) {
+                               error = ENOSPC;
+                               goto out;
+                       }
+                       ef->progtab[pb].size = shdr[i].sh_size;
+                       ef->progtab[pb].sec = i;
+                       if (shdr[i].sh_type == SHT_PROGBITS) {
+                               error = vn_rdwr(UIO_READ, vp,
+                                               ef->progtab[pb].addr,
+                                               shdr[i].sh_size, shdr[i].sh_offset,
+                                               UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred,
+                                               &resid);
+                               if (error)
+                                       goto out;
+                               if (resid != 0) {
+                                       error = EINVAL;
+                                       goto out;
+                               }
+#if 0
+                               /* Initialize the per-cpu or vnet area. */
+                               if (ef->progtab[pb].addr != (void *)mapbase &&
+                                   !strcmp(ef->progtab[pb].name, "set_pcpu"))
+                                       dpcpu_copy(ef->progtab[pb].addr,
+                                                  shdr[i].sh_size);
+#ifdef VIMAGE
+                               else if (ef->progtab[pb].addr !=
+                                        (void *)mapbase &&
+                                        !strcmp(ef->progtab[pb].name, VNET_SETNAME))
+                                       vnet_data_copy(ef->progtab[pb].addr,
+                                                      shdr[i].sh_size);
+#endif
+#endif
+                       } else
+                               bzero(ef->progtab[pb].addr, shdr[i].sh_size);
+
+                       /* Update all symbol values with the offset. */
+                       for (j = 0; j < ef->ddbsymcnt; j++) {
+                               es = &ef->ddbsymtab[j];
+                               if (es->st_shndx != i)
+                                       continue;
+                               es->st_value += (Elf_Addr) ef->progtab[pb].addr;
+                       }
+                       mapbase += shdr[i].sh_size;
+                       pb++;
+                       break;
+               case SHT_REL:
+                       ef->reltab[rl].rel = kmalloc(shdr[i].sh_size, M_LINKER, M_WAITOK);
+                       ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel);
+                       ef->reltab[rl].sec = shdr[i].sh_info;
+                       error = vn_rdwr(UIO_READ, vp,
+                                       (void *)ef->reltab[rl].rel,
+                                       shdr[i].sh_size, shdr[i].sh_offset,
+                                       UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
+                       if (error)
+                               goto out;
+                       if (resid != 0) {
+                               error = EINVAL;
+                               goto out;
+                       }
+                       rl++;
+                       break;
+               case SHT_RELA:
+                       ef->relatab[ra].rela = kmalloc(shdr[i].sh_size, M_LINKER, M_WAITOK);
+                       ef->relatab[ra].nrela = shdr[i].sh_size / sizeof(Elf_Rela);
+                       ef->relatab[ra].sec = shdr[i].sh_info;
+                       error = vn_rdwr(UIO_READ, vp,
+                                       (void *)ef->relatab[ra].rela,
+                                       shdr[i].sh_size, shdr[i].sh_offset,
+                                       UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
+                       if (error)
+                               goto out;
+                       if (resid != 0) {
+                               error = EINVAL;
+                               goto out;
+                       }
+                       ra++;
+                       break;
+               }
+       }
+       if (pb != ef->nprogtab)
+               panic("lost progbits");
+       if (rl != ef->nreltab)
+               panic("lost reltab");
+       if (ra != ef->nrelatab)
+               panic("lost relatab");
+       if (mapbase != (vm_offset_t) ef->address + mapsize)
+               panic("mapbase 0x%lx != address %p + mapsize 0x%lx (0x%lx)\n",
+                     mapbase, ef->address, mapsize,
+                     (vm_offset_t) ef->address + mapsize);
+
+       /* Local intra-module relocations */
+       link_elf_obj_reloc_local(lf);
+
+       /* Pull in dependencies */
+       error = linker_load_dependencies(lf);
+       if (error)
+               goto out;
+
+       /* External relocations */
+       error = relocate_file(lf);
+       if (error)
+               goto out;
+
+       *result = lf;
+
+out:
+       if (error && lf)
+               linker_file_unload(lf /*, LINKER_UNLOAD_FORCE */);
+       if (hdr)
+               kfree(hdr, M_LINKER);
+       vn_unlock(vp);
+       vn_close(vp, FREAD);
+
+       return error;
+}
+
+static void
+link_elf_obj_unload_file(linker_file_t file)
+{
+       elf_file_t      ef = file->priv;
+       int i;
+
+       if (ef->progtab) {
+               for (i = 0; i < ef->nprogtab; i++) {
+                       if (ef->progtab[i].size == 0)
+                               continue;
+                       if (ef->progtab[i].name == NULL)
+                               continue;
+#if 0
+                       if (!strcmp(ef->progtab[i].name, "set_pcpu"))
+                               dpcpu_free(ef->progtab[i].addr,
+                                   ef->progtab[i].size);
+#ifdef VIMAGE
+                       else if (!strcmp(ef->progtab[i].name, VNET_SETNAME))
+                               vnet_data_free(ef->progtab[i].addr,
+                                   ef->progtab[i].size);
+#endif
+#endif
+               }
+       }
+       if (ef->preloaded) {
+               if (ef->reltab)
+                       kfree(ef->reltab, M_LINKER);
+               if (ef->relatab)
+                       kfree(ef->relatab, M_LINKER);
+               if (ef->progtab)
+                       kfree(ef->progtab, M_LINKER);
+               if (ef->ctftab)
+                       kfree(ef->ctftab, M_LINKER);
+               if (ef->ctfoff)
+                       kfree(ef->ctfoff, M_LINKER);
+               if (ef->typoff)
+                       kfree(ef->typoff, M_LINKER);
+               if (file->filename != NULL)
+                       preload_delete_name(file->filename);
+               kfree(ef, M_LINKER);
+               /* XXX reclaim module memory? */
+               return;
+       }
+
+       for (i = 0; i < ef->nreltab; i++)
+               if (ef->reltab[i].rel)
+                       kfree(ef->reltab[i].rel, M_LINKER);
+       for (i = 0; i < ef->nrelatab; i++)
+               if (ef->relatab[i].rela)
+                       kfree(ef->relatab[i].rela, M_LINKER);
+       if (ef->reltab)
+               kfree(ef->reltab, M_LINKER);
+       if (ef->relatab)
+               kfree(ef->relatab, M_LINKER);
+       if (ef->progtab)
+               kfree(ef->progtab, M_LINKER);
+
+       if (ef->object) {
+               vm_map_remove(&kernel_map, (vm_offset_t) ef->address,
+                   (vm_offset_t) ef->address +
+                   (ef->object->size << PAGE_SHIFT));
+       }
+       if (ef->e_shdr)
+               kfree(ef->e_shdr, M_LINKER);
+       if (ef->ddbsymtab)
+               kfree(ef->ddbsymtab, M_LINKER);
+       if (ef->ddbstrtab)
+               kfree(ef->ddbstrtab, M_LINKER);
+       if (ef->shstrtab)
+               kfree(ef->shstrtab, M_LINKER);
+       if (ef->ctftab)
+               kfree(ef->ctftab, M_LINKER);
+       if (ef->ctfoff)
+               kfree(ef->ctfoff, M_LINKER);
+       if (ef->typoff)
+               kfree(ef->typoff, M_LINKER);
+       kfree(ef, M_LINKER);
+}
+
+static const char *
+symbol_name(elf_file_t ef, Elf_Size r_info)
+{
+       const Elf_Sym  *ref;
+
+       if (ELF_R_SYM(r_info)) {
+               ref = ef->ddbsymtab + ELF_R_SYM(r_info);
+               return ef->ddbstrtab + ref->st_name;
+       } else
+               return NULL;
+}
+
+static Elf_Addr
+findbase(elf_file_t ef, int sec)
+{
+       int i;
+       Elf_Addr base = 0;
+
+       for (i = 0; i < ef->nprogtab; i++) {
+               if (sec == ef->progtab[i].sec) {
+                       base = (Elf_Addr)ef->progtab[i].addr;
+                       break;
+               }
+       }
+       return base;
+}
+
+static int
+relocate_file(linker_file_t lf)
+{
+       elf_file_t      ef = lf->priv;
+       const Elf_Rel *rellim;
+       const Elf_Rel *rel;
+       const Elf_Rela *relalim;
+       const Elf_Rela *rela;
+       const char *symname;
+       const Elf_Sym *sym;
+       int i;
+       Elf_Size symidx;
+       Elf_Addr base;
+
+       /* Perform relocations without addend if there are any: */
+       for (i = 0; i < ef->nreltab; i++) {
+               rel = ef->reltab[i].rel;
+               if (rel == NULL)
+                       panic("lost a reltab!");
+               rellim = rel + ef->reltab[i].nrel;
+               base = findbase(ef, ef->reltab[i].sec);
+               if (base == 0)
+                       panic("lost base for reltab");
+               for ( ; rel < rellim; rel++) {
+                       symidx = ELF_R_SYM(rel->r_info);
+                       if (symidx >= ef->ddbsymcnt)
+                               continue;
+                       sym = ef->ddbsymtab + symidx;
+                       /* Local relocs are already done */
+                       if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
+                               continue;
+                       if (elf_reloc(lf, base, rel, ELF_RELOC_REL,
+                           elf_obj_lookup)) {
+                               symname = symbol_name(ef, rel->r_info);
+                               kprintf("link_elf_obj_obj: symbol %s undefined\n",
+                                   symname);
+                               return ENOENT;
+                       }
+               }
+       }
+
+       /* Perform relocations with addend if there are any: */
+       for (i = 0; i < ef->nrelatab; i++) {
+               rela = ef->relatab[i].rela;
+               if (rela == NULL)
+                       panic("lost a relatab!");
+               relalim = rela + ef->relatab[i].nrela;
+               base = findbase(ef, ef->relatab[i].sec);
+               if (base == 0)
+                       panic("lost base for relatab");
+               for ( ; rela < relalim; rela++) {
+                       symidx = ELF_R_SYM(rela->r_info);
+                       if (symidx >= ef->ddbsymcnt)
+                               continue;
+                       sym = ef->ddbsymtab + symidx;
+                       /* Local relocs are already done */
+                       if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
+                               continue;
+                       if (elf_reloc(lf, base, rela, ELF_RELOC_RELA,
+                           elf_obj_lookup)) {
+                               symname = symbol_name(ef, rela->r_info);
+                               kprintf("link_elf_obj_obj: symbol %s undefined\n",
+                                   symname);
+                               return ENOENT;
+                       }
+               }
+       }
+
+       return 0;
+}
+
+static int
+link_elf_obj_lookup_symbol(linker_file_t lf, const char *name, c_linker_sym_t *sym)
+{
+       elf_file_t ef = lf->priv;
+       const Elf_Sym *symp;
+       const char *strp;
+       int i;
+
+       for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
+               strp = ef->ddbstrtab + symp->st_name;
+               if (symp->st_shndx != SHN_UNDEF && strcmp(name, strp) == 0) {
+                       *sym = (c_linker_sym_t) symp;
+                       return 0;
+               }
+       }
+       return ENOENT;
+}
+
+static int
+link_elf_obj_symbol_values(linker_file_t lf, c_linker_sym_t sym,
+    linker_symval_t *symval)
+{
+       elf_file_t ef = lf->priv;
+       const Elf_Sym *es = (const Elf_Sym*) sym;
+
+       if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) {
+               symval->name = ef->ddbstrtab + es->st_name;
+               symval->value = (caddr_t)es->st_value;
+               symval->size = es->st_size;
+               return 0;
+       }
+       return ENOENT;
+}
+
+static int
+link_elf_obj_search_symbol(linker_file_t lf, caddr_t value,
+    c_linker_sym_t *sym, long *diffp)
+{
+       elf_file_t ef = lf->priv;
+       u_long off = (uintptr_t) (void *) value;
+       u_long diff = off;
+       u_long st_value;
+       const Elf_Sym *es;
+       const Elf_Sym *best = 0;
+       int i;
+
+       for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) {
+               if (es->st_name == 0)
+                       continue;
+               st_value = es->st_value;
+               if (off >= st_value) {
+                       if (off - st_value < diff) {
+                               diff = off - st_value;
+                               best = es;
+                               if (diff == 0)
+                                       break;
+                       } else if (off - st_value == diff) {
+                               best = es;
+                       }
+               }
+       }
+       if (best == 0)
+               *diffp = off;
+       else
+               *diffp = diff;
+       *sym = (c_linker_sym_t) best;
+
+       return 0;
+}
+
+/*
+ * Look up a linker set on an ELF system.
+ */
+static int
+link_elf_obj_lookup_set(linker_file_t lf, const char *name,
+    void ***startp, void ***stopp, int *countp)
+{
+       elf_file_t ef = lf->priv;
+       void **start, **stop;
+       int i, count;
+
+       /* Relative to section number */
+       for (i = 0; i < ef->nprogtab; i++) {
+               if ((strncmp(ef->progtab[i].name, "set_", 4) == 0) &&
+                   strcmp(ef->progtab[i].name + 4, name) == 0) {
+                       start  = (void **)ef->progtab[i].addr;
+                       stop = (void **)((char *)ef->progtab[i].addr +
+                           ef->progtab[i].size);
+                       count = stop - start;
+                       if (startp)
+                               *startp = start;
+                       if (stopp)
+                               *stopp = stop;
+                       if (countp)
+                               *countp = count;
+                       return (0);
+               }
+       }
+       return (ESRCH);
+}
+
+/*
+ * Symbol lookup function that can be used when the symbol index is known (ie
+ * in relocations). It uses the symbol index instead of doing a fully fledged
+ * hash table based lookup when such is valid. For example for local symbols.
+ * This is not only more efficient, it's also more correct. It's not always
+ * the case that the symbol can be found through the hash table.
+ */
+static int
+elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *result)
+{
+       elf_file_t ef = lf->priv;
+       const Elf_Sym *sym;
+       const char *symbol;
+
+       /* Don't even try to lookup the symbol if the index is bogus. */
+       if (symidx >= ef->ddbsymcnt)
+               return (ENOENT);
+
+       sym = ef->ddbsymtab + symidx;
+
+       /* Quick answer if there is a definition included. */
+       if (sym->st_shndx != SHN_UNDEF) {
+               *result = sym->st_value;
+               return (0);
+       }
+
+       /* If we get here, then it is undefined and needs a lookup. */
+       switch (ELF_ST_BIND(sym->st_info)) {
+       case STB_LOCAL:
+               /* Local, but undefined? huh? */
+               return (ENOENT);
+
+       case STB_GLOBAL:
+               /* Relative to Data or Function name */
+               symbol = ef->ddbstrtab + sym->st_name;
+
+               /* Force a lookup failure if the symbol name is bogus. */
+               if (*symbol == 0)
+                       return (ENOENT);
+               return (linker_file_lookup_symbol(lf, symbol, deps, (caddr_t *)result));
+
+       case STB_WEAK:
+               kprintf("link_elf_obj_obj: Weak symbols not supported\n");
+               return (ENOENT);
+
+       default:
+               return (ENOENT);
+       }
+}
+
+static void
+link_elf_obj_fix_link_set(elf_file_t ef)
+{
+       static const char startn[] = "__start_";
+       static const char stopn[] = "__stop_";
+       Elf_Sym *sym;
+       const char *sym_name, *linkset_name;
+       Elf_Addr startp, stopp;
+       Elf_Size symidx;
+       int start, i;
+
+       startp = stopp = 0;
+       for (symidx = 1 /* zero entry is special */;
+               symidx < ef->ddbsymcnt; symidx++) {
+               sym = ef->ddbsymtab + symidx;
+               if (sym->st_shndx != SHN_UNDEF)
+                       continue;
+
+               sym_name = ef->ddbstrtab + sym->st_name;
+               if (strncmp(sym_name, startn, sizeof(startn) - 1) == 0) {
+                       start = 1;
+                       linkset_name = sym_name + sizeof(startn) - 1;
+               }
+               else if (strncmp(sym_name, stopn, sizeof(stopn) - 1) == 0) {
+                       start = 0;
+                       linkset_name = sym_name + sizeof(stopn) - 1;
+               }
+               else
+                       continue;
+
+               for (i = 0; i < ef->nprogtab; i++) {
+                       if (strcmp(ef->progtab[i].name, linkset_name) == 0) {
+                               startp = (Elf_Addr)ef->progtab[i].addr;
+                               stopp = (Elf_Addr)(startp + ef->progtab[i].size);
+                               break;
+                       }
+               }
+               if (i == ef->nprogtab)
+                       continue;
+
+               sym->st_value = start ? startp : stopp;
+               sym->st_shndx = i;
+       }
+}
+
+static void
+link_elf_obj_reloc_local(linker_file_t lf)
+{
+       elf_file_t ef = lf->priv;
+       const Elf_Rel *rellim;
+       const Elf_Rel *rel;
+       const Elf_Rela *relalim;
+       const Elf_Rela *rela;
+       const Elf_Sym *sym;
+       Elf_Addr base;
+       int i;
+       Elf_Size symidx;
+
+       link_elf_obj_fix_link_set(ef);
+
+       /* Perform relocations without addend if there are any: */
+       for (i = 0; i < ef->nreltab; i++) {
+               rel = ef->reltab[i].rel;
+               if (rel == NULL)
+                       panic("lost a reltab!");
+               rellim = rel + ef->reltab[i].nrel;
+               base = findbase(ef, ef->reltab[i].sec);
+               if (base == 0)
+                       panic("lost base for reltab");
+               for ( ; rel < rellim; rel++) {
+                       symidx = ELF_R_SYM(rel->r_info);
+                       if (symidx >= ef->ddbsymcnt)
+                               continue;
+                       sym = ef->ddbsymtab + symidx;
+                       /* Only do local relocs */
+                       if (ELF_ST_BIND(sym->st_info) != STB_LOCAL)
+                               continue;
+                       elf_reloc_local(lf, base, rel, ELF_RELOC_REL,
+                           elf_obj_lookup);
+               }
+       }
+
+       /* Perform relocations with addend if there are any: */
+       for (i = 0; i < ef->nrelatab; i++) {
+               rela = ef->relatab[i].rela;
+               if (rela == NULL)
+                       panic("lost a relatab!");
+               relalim = rela + ef->relatab[i].nrela;
+               base = findbase(ef, ef->relatab[i].sec);
+               if (base == 0)
+                       panic("lost base for relatab");
+               for ( ; rela < relalim; rela++) {
+                       symidx = ELF_R_SYM(rela->r_info);
+                       if (symidx >= ef->ddbsymcnt)
+                               continue;
+                       sym = ef->ddbsymtab + symidx;
+                       /* Only do local relocs */
+                       if (ELF_ST_BIND(sym->st_info) != STB_LOCAL)
+                               continue;
+                       elf_reloc_local(lf, base, rela, ELF_RELOC_RELA,
+                           elf_obj_lookup);
+               }
+       }
+}
index 8019f21..8be5fa4 100644 (file)
@@ -69,6 +69,7 @@ dev/misc/syscons/scvidctl.c           optional        sc
 dev/misc/syscons/scvtb.c               optional        sc
 dev/misc/syscons/syscons.c             optional        sc
 dev/misc/syscons/sysmouse.c            optional        sc
+kern/link_elf_obj.c            standard
 vfs/smbfs/smbfs_io.c           optional        smbfs
 vfs/smbfs/smbfs_node.c         optional        smbfs
 vfs/smbfs/smbfs_smb.c          optional        smbfs