diff options
author | Roland McGrath <roland@gnu.org> | 1995-06-08 06:57:14 +0000 |
---|---|---|
committer | Roland McGrath <roland@gnu.org> | 1995-06-08 06:57:14 +0000 |
commit | 3043a1a67d8ba863ea7eb8b860ac935ee308b3ea (patch) | |
tree | eb08b6863a760ab141aecb5c8812ae4179ab9094 /exec | |
parent | 4a851fbfe70235a1a64b5eab360fbc46e8ea6847 (diff) |
(struct execdata.info.elf): Add members `anywhere' and `loadbase'.
(load_section): Use them; if `anywhere' set, load the section anywhere.
Record load address in `loadbase'.
(check_elf): Initialize `anywhere' and `loadbase'.
(postload): Merged into load.
(load): Perform postload functionality here, after calling finish_mapping.
(finish): Take new flag arg; deallocate file port only if set.
(do_exec): Pass flag to finish appropriately.
Don't call finish_mapping and postload after load.
KLUDGE: Load the interpreter before the program instead of after.
Diffstat (limited to 'exec')
-rw-r--r-- | exec/exec.c | 290 |
1 files changed, 167 insertions, 123 deletions
diff --git a/exec/exec.c b/exec/exec.c index c6762465..f8b343f2 100644 --- a/exec/exec.c +++ b/exec/exec.c @@ -98,6 +98,8 @@ struct execdata By `load' it is local alloca'd storage. */ Elf32_Phdr *phdr; Elf32_Word phnum; /* Number of program header table elements. */ + int anywhere; /* Nonzero if image can go anywhere. */ + vm_address_t loadbase; /* Actual mapping location. */ } elf; } info; }; @@ -193,6 +195,8 @@ load_section (void *section, struct execdata *u) vm_offset_t filepos = 0; vm_size_t filesz = 0, memsz = 0; vm_prot_t vm_prot; + int anywhere; + vm_address_t mask = 0; #ifdef BFD asection *const sec = section; #endif @@ -218,6 +222,7 @@ load_section (void *section, struct execdata *u) filesz = (sec->flags & SEC_LOAD) ? memsz : 0; if (sec->flags & (SEC_READONLY|SEC_ROM)) vm_prot &= ~VM_PROT_WRITE; + anywhere = 0; } else #endif @@ -232,6 +237,24 @@ load_section (void *section, struct execdata *u) vm_prot &= ~VM_PROT_WRITE; if ((ph->p_flags & PF_X) == 0) vm_prot &= ~VM_PROT_EXECUTE; + anywhere = u->info.elf.anywhere; + if (! anywhere) + addr += u->info.elf.loadbase; + else + switch (elf_machine) + { + case EM_386: + case EM_486: + /* On the i386, programs normally load at 0x08000000, and + expect their data segment to be able to grow dynamically + upward from its start near that address. We need to make + sure that the dynamic linker is not mapped in a conflicting + address. */ + /* mask = 0xf8000000UL; */ /* XXX */ + break; + default: + break; + } } if (memsz == 0) @@ -249,7 +272,7 @@ load_section (void *section, struct execdata *u) vm_size_t off = size % vm_page_size; /* Allocate with vm_map to set max protections. */ u->error = vm_map (u->task, - &mapstart, size, 0, 0, + &mapstart, size, mask, anywhere, MACH_PORT_NULL, 0, 1, vm_prot|VM_PROT_WRITE, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE, @@ -291,7 +314,8 @@ load_section (void *section, struct execdata *u) else if (u->filemap != MACH_PORT_NULL) /* Map the data into the task directly from the file. */ u->error = vm_map (u->task, - &mapstart, filesz - (mapstart - addr), 0, 0, + &mapstart, filesz - (mapstart - addr), + mask, anywhere, u->filemap, filepos + (mapstart - addr), 1, vm_prot, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE, @@ -318,6 +342,17 @@ load_section (void *section, struct execdata *u) } if (u->error) return; + + if (anywhere) + { + /* We let the kernel choose the location of the mapping. + Now record where it ended up. Later sections cannot + be mapped anywhere, they must come after this one. */ + u->info.elf.loadbase = mapstart; + addr = mapstart + (addr % vm_page_size); + anywhere = u->info.elf.anywhere = 0; + mask = 0; + } } if (mapstart > addr) @@ -405,11 +440,23 @@ load_section (void *section, struct execdata *u) /* MAPSTART is the first page that starts inside the section. Allocate all the pages that start inside the section. */ - if (u->error = vm_allocate (u->task, &mapstart, - memsz - (mapstart - addr), 0)) + if (u->error = vm_map (u->task, &mapstart, memsz - (mapstart - addr), + mask, anywhere, MACH_PORT_NULL, 0, 1, + vm_prot, VM_PROT_ALL, VM_INHERIT_COPY)) return; } + if (anywhere) + { + /* We let the kernel choose the location of the zero space. + Now record where it ended up. Later sections cannot + be mapped anywhere, they must come after this one. */ + u->info.elf.loadbase = mapstart; + addr = mapstart + (addr % vm_page_size); + anywhere = u->info.elf.anywhere = 0; + mask = 0; + } + if (mapstart > addr) { /* Zero space in the section before the first page boundary. */ @@ -729,6 +776,10 @@ check_elf (struct execdata *e) return; } e->info.elf.phdr = phdr; + + e->info.elf.anywhere = (ehdr->e_type == ET_DYN || + ehdr->e_type == ET_REL); + e->info.elf.loadbase = 0; } static void @@ -778,87 +829,6 @@ check (struct execdata *e) } -/* Load the file. */ -static void -load (task_t usertask, struct execdata *e) -{ - if (e->error) - return; - - e->task = usertask; -#ifdef BFD - if (e->bfd) - { - void load_bfd_section (bfd *bfd, asection *sec, void *userdata) - { - load_section (sec, userdata); - } - bfd_map_over_sections (e->bfd, &load_bfd_section, e); - } - else -#endif - { - Elf32_Word i; - for (i = 0; i < e->info.elf.phnum; ++i) - if (e->info.elf.phdr[i].p_type == PT_LOAD) - load_section (&e->info.elf.phdr[i], e); - } -} - -/* Do post-loading processing on the task. */ -static void -postload (struct execdata *e) -{ - if (e->error) - return; - -#ifdef BFD - if (e->bfd) - { - /* Do post-loading processing for a section. This consists of - peeking the pages of non-demand-paged executables. */ - - void postload_section (bfd *bfd, asection *sec, void *userdata) - { - struct execdata *u = userdata; - vm_address_t addr = 0; - vm_size_t secsize = 0; - - addr = (vm_address_t) sec->vma; - secsize = sec->_raw_size; - - if ((sec->flags & SEC_LOAD) && !(bfd->flags & D_PAGED)) - { - /* Pre-load the section by peeking every mapped page. */ - vm_address_t myaddr, a; - vm_size_t mysize; - myaddr = 0; - - /* We have already mapped the file into the task in - load_section. Now read from the task's memory into our - own address space so we can peek each page and cause it to - be paged in. */ - if (u->error = vm_read (u->task, - trunc_page (addr), round_page (secsize), - &myaddr, &mysize)) - return; - - /* Peek at the first word of each page. */ - for (a = ((myaddr + mysize) & ~(vm_page_size - 1)); - a >= myaddr; a -= vm_page_size) - /* Force it to be paged in. */ - (void) *(volatile int *) a; - - vm_deallocate (mach_task_self (), myaddr, mysize); - } - } - - bfd_map_over_sections (e->bfd, postload_section, e); - } -#endif -} - - /* Release the conch and clean up mapping the file and control page. */ static void finish_mapping (struct execdata *e) @@ -893,21 +863,111 @@ finish_mapping (struct execdata *e) /* Clean up after reading the file (need not be completed). */ static void -finish (struct execdata *e) +finish (struct execdata *e, int dealloc_file) { finish_mapping (e); #ifdef BFD if (e->bfd != NULL) - bfd_close (e->bfd); + { + bfd_close (e->bfd); + e->bfd = NULL; + } else #endif fclose (&e->stream); - if (e->file != MACH_PORT_NULL) + if (dealloc_file && e->file != MACH_PORT_NULL) { mach_port_deallocate (mach_task_self (), e->file); e->file = MACH_PORT_NULL; } } + + +/* Load the file. */ +static void +load (task_t usertask, struct execdata *e) +{ + e->task = usertask; + + if (! e->error) + { +#ifdef BFD + if (e->bfd) + { + void load_bfd_section (bfd *bfd, asection *sec, void *userdata) + { + load_section (sec, userdata); + } + bfd_map_over_sections (e->bfd, &load_bfd_section, e); + } + else +#endif + { + Elf32_Word i; + for (i = 0; i < e->info.elf.phnum; ++i) + if (e->info.elf.phdr[i].p_type == PT_LOAD) + load_section (&e->info.elf.phdr[i], e); + + /* The entry point address is relative to whereever we loaded the + program text. */ + e->entry += e->info.elf.loadbase; + } + } + + /* Release the conch for the file. */ + finish_mapping (e); + + if (! e->error) + { + /* Do post-loading processing on the task. */ + +#ifdef BFD + if (e->bfd) + { + /* Do post-loading processing for a section. This consists of + peeking the pages of non-demand-paged executables. */ + + void postload_section (bfd *bfd, asection *sec, void *userdata) + { + struct execdata *u = userdata; + vm_address_t addr = 0; + vm_size_t secsize = 0; + + addr = (vm_address_t) sec->vma; + secsize = sec->_raw_size; + + if ((sec->flags & SEC_LOAD) && !(bfd->flags & D_PAGED)) + { + /* Pre-load the section by peeking every mapped page. */ + vm_address_t myaddr, a; + vm_size_t mysize; + myaddr = 0; + + /* We have already mapped the file into the task in + load_section. Now read from the task's memory into our + own address space so we can peek each page and cause it to + be paged in. */ + if (u->error = vm_read (u->task, + trunc_page (addr), round_page (secsize), + &myaddr, &mysize)) + return; + + /* Peek at the first word of each page. */ + for (a = ((myaddr + mysize) & ~(vm_page_size - 1)); + a >= myaddr; a -= vm_page_size) + /* Force it to be paged in. */ + (void) *(volatile int *) a; + + vm_deallocate (mach_task_self (), myaddr, mysize); + } + } + + bfd_map_over_sections (e->bfd, postload_section, e); + } + } +#endif + +} #ifdef GZIP /* Check the file for being a gzip'd image. Return with ENOEXEC means not @@ -998,7 +1058,7 @@ check_gzip (struct execdata *earg) e->file_size = zipdatasz; /* Clean up the old exec file stream's state. */ - finish (e); + finish (e, 0); /* Point the stream at the buffer of file data. */ memset (&e->stream, 0, sizeof (e->stream)); @@ -1120,7 +1180,6 @@ do_exec (mach_port_t execserver, mach_port_t *destroynames, u_int ndestroynames) { struct execdata e, interp; - int finished = 0; task_t newtask = MACH_PORT_NULL; thread_t thread = MACH_PORT_NULL; struct bootinfo *boot = 0; @@ -1278,9 +1337,9 @@ do_exec (mach_port_t execserver, if (e.error) { - if (interp.file != MACH_PORT_NULL) - finish (&interp); - finish (&e); + if (e.interp.section) + finish (&interp, 1); + finish (&e, 0); return e.error; } @@ -1335,39 +1394,30 @@ do_exec (mach_port_t execserver, newtask = oldtask; } - /* Load the file into the task. */ - load (newtask, &e); - if (e.error) - goto out; - - /* Release the conch for the file. */ - finish_mapping (&e); - - /* Further frobnicate the task after loading from the file. */ - postload (&e); - if (e.error) - goto out; - +/* XXX this should be below + it is here to work around a vm_map kernel bug. */ if (interp.file != MACH_PORT_NULL) { /* Load the interpreter file. */ load (newtask, &interp); - if (! interp.error) - { - finish_mapping (&interp); - postload (&interp); - } if (interp.error) { e.error = interp.error; goto out; } - finish (&interp); + finish (&interp, 1); } + + /* Load the file into the task. */ + load (newtask, &e); + if (e.error) + goto out; + + /* XXX loading of interp belongs here */ + /* Clean up. */ - finish (&e); - finished = 1; + finish (&e, 0); /* Create the initial thread. */ if (e.error = thread_create (newtask, &thread)) @@ -1595,15 +1645,9 @@ do_exec (mach_port_t execserver, task_terminate (newtask); mach_port_deallocate (mach_task_self (), newtask); } - if (!finished) - { - if (interp.file != MACH_PORT_NULL) - finish (&interp); - if (e.error) - /* Don't deallocate this port; mig will do it for us. */ - e.file = MACH_PORT_NULL; - finish (&e); - } + if (e.interp.section) + finish (&interp, 1); + finish (&e, !e.error); if (oldtask != newtask) task_resume (oldtask); |