/*
* Run the chain and if the bottom-most object is a vnode-type lock the
* underlying vnode. A locked vnode or NULL is returned.
*/
struct vnode *
vnode_pager_lock(vm_object_t object)
{
struct vnode *vp = NULL;
vm_object_t lobject;
vm_object_t tobject;
int error;
if (object == NULL)
return(NULL);
ASSERT_LWKT_TOKEN_HELD(vm_object_token(object));
lobject = object;
while (lobject->type != OBJT_VNODE) {
if (lobject->flags & OBJ_DEAD)
break;
tobject = lobject->backing_object;
if (tobject == NULL)
break;
vm_object_hold_shared(tobject);
if (tobject == lobject->backing_object) {
if (lobject != object) {
vm_object_lock_swap();
vm_object_drop(lobject);
}
lobject = tobject;
} else {
vm_object_drop(tobject);
}
}
while (lobject->type == OBJT_VNODE &&
(lobject->flags & OBJ_DEAD) == 0) {
/*
* Extract the vp
*/
vp = lobject->handle;
error = vget(vp, LK_SHARED | LK_RETRY | LK_CANRECURSE);
if (error == 0) {
if (lobject->handle == vp)
break;
vput(vp);
} else {
kprintf("vnode_pager_lock: vp %p error %d "
"lockstatus %d, retrying\n",
vp, error,
lockstatus(&vp->v_lock, curthread));
tsleep(object->handle, 0, "vnpgrl", hz);
}
vp = NULL;
}
if (lobject != object)
vm_object_drop(lobject);
return (vp);
}
/*
* Add a ref to a vnode's existing VM object, return the object or
* NULL if the vnode did not have one. This does not create the
* object (we can't since we don't know what the proper blocksize/boff
* is to match the VFS's use of the buffer cache).
*/
vm_object_t
vnode_pager_reference(struct vnode *vp)
{
vm_object_t object;
/*
* Prevent race condition when allocating the object. This
* can happen with NFS vnodes since the nfsnode isn't locked.
*
* Serialize potential vnode/object teardowns and interlocks
*/
lwkt_gettoken(&vp->v_token);
while (vp->v_flag & VOLOCK) {
vsetflags(vp, VOWANT);
tsleep(vp, 0, "vnpobj", 0);
}
vsetflags(vp, VOLOCK);
lwkt_reltoken(&vp->v_token);
/*
* Prevent race conditions against deallocation of the VM
* object.
*/
while ((object = vp->v_object) != NULL) {
vm_object_hold(object);
if ((object->flags & OBJ_DEAD) == 0)
break;
vm_object_dead_sleep(object, "vadead");
vm_object_drop(object);
}
/*
* The object is expected to exist, the caller will handle
* NULL returns if it does not.
*/
if (object) {
object->ref_count++;
vref(vp);
}
lwkt_gettoken(&vp->v_token);
vclrflags(vp, VOLOCK);
if (vp->v_flag & VOWANT) {
vclrflags(vp, VOWANT);
wakeup(vp);
}
lwkt_reltoken(&vp->v_token);
if (object)
vm_object_drop(object);
return (object);
}
static int old_dev_pager_fault(vm_object_t object, vm_ooffset_t offset,
int prot, vm_page_t *mres)
{
vm_paddr_t paddr;
vm_page_t page;
vm_offset_t pidx = OFF_TO_IDX(offset);
cdev_t dev;
page = *mres;
dev = object->handle;
paddr = pmap_phys_address(
dev_dmmap(dev, offset, prot, NULL));
KASSERT(paddr != -1,("dev_pager_getpage: map function returns error"));
KKASSERT(object->type == OBJT_DEVICE);
if (page->flags & PG_FICTITIOUS) {
/*
* If the passed in reqpage page is already a fake page,
* update it with the new physical address.
*/
page->phys_addr = paddr;
page->valid = VM_PAGE_BITS_ALL;
} else {
/*
* Replace the passed in reqpage page with our own fake page
* and free up all the original pages.
*/
page = dev_pager_getfake(paddr, object->memattr);
TAILQ_INSERT_TAIL(&object->un_pager.devp.devp_pglist,
page, pageq);
vm_object_hold(object);
vm_page_free(*mres);
if (vm_page_insert(page, object, pidx) == FALSE) {
panic("dev_pager_getpage: page (%p,%016jx) exists",
object, (uintmax_t)pidx);
}
vm_object_drop(object);
}
return (VM_PAGER_OK);
}
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;
/* XXX Hack for firmware loading where p == NULL */
if (p == NULL) {
p = &proc0;
}
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);
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 = NULL;
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);
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++) {
if (shdr[i].sh_size == 0)
continue;
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);
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);
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);
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++) {
if (shdr[i].sh_size == 0)
continue;
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;
}
vm_object_hold(ef->object);
vm_object_reference_locked(ef->object);
ef->address = (caddr_t) vm_map_min(&kernel_map);
ef->bytes = 0;
/*
* In order to satisfy x86_64's architectural requirements on the
* location of code and data in the kernel's address space, request a
* mapping that is above the kernel.
*
* vkernel64's text+data is outside the managed VM space entirely.
*/
#if defined(__x86_64__) && defined(_KERNEL_VIRTUAL)
error = vkernel_module_memory_alloc(&mapbase, round_page(mapsize));
vm_object_drop(ef->object);
#else
mapbase = KERNBASE;
error = vm_map_find(&kernel_map, ef->object, NULL,
0, &mapbase, round_page(mapsize),
PAGE_SIZE,
TRUE, VM_MAPTYPE_NORMAL,
VM_PROT_ALL, VM_PROT_ALL, FALSE);
vm_object_drop(ef->object);
if (error) {
vm_object_deallocate(ef->object);
ef->object = NULL;
goto out;
}
/* Wire the pages */
error = vm_map_wire(&kernel_map, mapbase,
mapbase + round_page(mapsize), 0);
#endif
if (error != KERN_SUCCESS) {
error = ENOMEM;
goto out;
}
/* Inform the kld system about the situation */
lf->address = ef->address = (caddr_t) mapbase;
lf->size = round_page(mapsize);
ef->bytes = 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++) {
if (shdr[i].sh_size == 0)
continue;
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)",
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, NULL);
return error;
}
vm_object_t
cdev_pager_allocate(void *handle, enum obj_type tp, struct cdev_pager_ops *ops,
vm_ooffset_t size, vm_prot_t prot, vm_ooffset_t foff, struct ucred *cred)
{
cdev_t dev;
vm_object_t object;
u_short color;
/*
* Offset should be page aligned.
*/
if (foff & PAGE_MASK)
return (NULL);
size = round_page64(size);
if (ops->cdev_pg_ctor(handle, size, prot, foff, cred, &color) != 0)
return (NULL);
/*
* Look up pager, creating as necessary.
*/
mtx_lock(&dev_pager_mtx);
object = vm_pager_object_lookup(&dev_pager_object_list, handle);
if (object == NULL) {
/*
* Allocate object and associate it with the pager.
*/
object = vm_object_allocate_hold(tp,
OFF_TO_IDX(foff + size));
object->handle = handle;
object->un_pager.devp.ops = ops;
object->un_pager.devp.dev = handle;
TAILQ_INIT(&object->un_pager.devp.devp_pglist);
/*
* handle is only a device for old_dev_pager_ctor.
*/
if (ops->cdev_pg_ctor == old_dev_pager_ctor) {
dev = handle;
dev->si_object = object;
}
TAILQ_INSERT_TAIL(&dev_pager_object_list, object,
pager_object_list);
vm_object_drop(object);
} else {
/*
* Gain a reference to the object.
*/
vm_object_hold(object);
vm_object_reference_locked(object);
if (OFF_TO_IDX(foff + size) > object->size)
object->size = OFF_TO_IDX(foff + size);
vm_object_drop(object);
}
mtx_unlock(&dev_pager_mtx);
return (object);
}
/*
* mincore system call handler
*
* mincore_args(const void *addr, size_t len, char *vec)
*
* No requirements
*/
int
sys_mincore(struct mincore_args *uap)
{
struct proc *p = curproc;
vm_offset_t addr, first_addr;
vm_offset_t end, cend;
pmap_t pmap;
vm_map_t map;
char *vec;
int error;
int vecindex, lastvecindex;
vm_map_entry_t current;
vm_map_entry_t entry;
int mincoreinfo;
unsigned int timestamp;
/*
* Make sure that the addresses presented are valid for user
* mode.
*/
first_addr = addr = trunc_page((vm_offset_t) uap->addr);
end = addr + (vm_size_t)round_page(uap->len);
if (end < addr)
return (EINVAL);
if (VM_MAX_USER_ADDRESS > 0 && end > VM_MAX_USER_ADDRESS)
return (EINVAL);
/*
* Address of byte vector
*/
vec = uap->vec;
map = &p->p_vmspace->vm_map;
pmap = vmspace_pmap(p->p_vmspace);
lwkt_gettoken(&map->token);
vm_map_lock_read(map);
RestartScan:
timestamp = map->timestamp;
if (!vm_map_lookup_entry(map, addr, &entry))
entry = entry->next;
/*
* Do this on a map entry basis so that if the pages are not
* in the current processes address space, we can easily look
* up the pages elsewhere.
*/
lastvecindex = -1;
for(current = entry;
(current != &map->header) && (current->start < end);
current = current->next) {
/*
* ignore submaps (for now) or null objects
*/
if (current->maptype != VM_MAPTYPE_NORMAL &&
current->maptype != VM_MAPTYPE_VPAGETABLE) {
continue;
}
if (current->object.vm_object == NULL)
continue;
/*
* limit this scan to the current map entry and the
* limits for the mincore call
*/
if (addr < current->start)
addr = current->start;
cend = current->end;
if (cend > end)
cend = end;
/*
* scan this entry one page at a time
*/
while (addr < cend) {
/*
* Check pmap first, it is likely faster, also
* it can provide info as to whether we are the
* one referencing or modifying the page.
*
* If we have to check the VM object, only mess
* around with normal maps. Do not mess around
* with virtual page tables (XXX).
*/
mincoreinfo = pmap_mincore(pmap, addr);
if (mincoreinfo == 0 &&
current->maptype == VM_MAPTYPE_NORMAL) {
vm_pindex_t pindex;
vm_ooffset_t offset;
vm_page_t m;
/*
* calculate the page index into the object
*/
offset = current->offset + (addr - current->start);
pindex = OFF_TO_IDX(offset);
/*
* if the page is resident, then gather
* information about it. spl protection is
* required to maintain the object
* association. And XXX what if the page is
* busy? What's the deal with that?
*
* XXX vm_token - legacy for pmap_ts_referenced
* in i386 and vkernel pmap code.
*/
lwkt_gettoken(&vm_token);
vm_object_hold(current->object.vm_object);
m = vm_page_lookup(current->object.vm_object,
pindex);
if (m && m->valid) {
mincoreinfo = MINCORE_INCORE;
if (m->dirty ||
pmap_is_modified(m))
mincoreinfo |= MINCORE_MODIFIED_OTHER;
if ((m->flags & PG_REFERENCED) ||
pmap_ts_referenced(m)) {
vm_page_flag_set(m, PG_REFERENCED);
mincoreinfo |= MINCORE_REFERENCED_OTHER;
}
}
vm_object_drop(current->object.vm_object);
lwkt_reltoken(&vm_token);
}
/*
* subyte may page fault. In case it needs to modify
* the map, we release the lock.
*/
vm_map_unlock_read(map);
/*
* calculate index into user supplied byte vector
*/
vecindex = OFF_TO_IDX(addr - first_addr);
/*
* If we have skipped map entries, we need to make sure that
* the byte vector is zeroed for those skipped entries.
*/
while((lastvecindex + 1) < vecindex) {
error = subyte( vec + lastvecindex, 0);
if (error) {
error = EFAULT;
goto done;
}
++lastvecindex;
}
/*
* Pass the page information to the user
*/
error = subyte( vec + vecindex, mincoreinfo);
if (error) {
error = EFAULT;
goto done;
}
/*
* If the map has changed, due to the subyte, the previous
* output may be invalid.
*/
vm_map_lock_read(map);
if (timestamp != map->timestamp)
goto RestartScan;
lastvecindex = vecindex;
addr += PAGE_SIZE;
}
}
/*
* subyte may page fault. In case it needs to modify
* the map, we release the lock.
*/
vm_map_unlock_read(map);
/*
* Zero the last entries in the byte vector.
*/
vecindex = OFF_TO_IDX(end - first_addr);
while((lastvecindex + 1) < vecindex) {
error = subyte( vec + lastvecindex, 0);
if (error) {
error = EFAULT;
goto done;
}
++lastvecindex;
}
/*
* If the map has changed, due to the subyte, the previous
* output may be invalid.
*/
vm_map_lock_read(map);
if (timestamp != map->timestamp)
goto RestartScan;
vm_map_unlock_read(map);
error = 0;
done:
lwkt_reltoken(&map->token);
return (error);
}
/*
* The map entries can *almost* be read with programs like cat. However,
* large maps need special programs to read. It is not easy to implement
* a program that can sense the required size of the buffer, and then
* subsequently do a read with the appropriate size. This operation cannot
* be atomic. The best that we can do is to allow the program to do a read
* with an arbitrarily large buffer, and return as much as we can. We can
* return an error code if the buffer is too small (EFBIG), then the program
* can try a bigger buffer.
*/
int
procfs_domap(struct proc *curp, struct lwp *lp, struct pfsnode *pfs,
struct uio *uio)
{
struct proc *p = lp->lwp_proc;
int len;
struct vnode *vp;
char *fullpath, *freepath;
int error;
vm_map_t map = &p->p_vmspace->vm_map;
pmap_t pmap = vmspace_pmap(p->p_vmspace);
vm_map_entry_t entry;
char mebuffer[MEBUFFERSIZE];
if (uio->uio_rw != UIO_READ)
return (EOPNOTSUPP);
if (uio->uio_offset != 0)
return (0);
error = 0;
vm_map_lock_read(map);
for (entry = map->header.next;
((uio->uio_resid > 0) && (entry != &map->header));
entry = entry->next) {
vm_object_t obj, tobj, lobj;
int ref_count, shadow_count, flags;
vm_offset_t addr;
vm_offset_t ostart;
int resident, privateresident;
char *type;
if (entry->maptype != VM_MAPTYPE_NORMAL &&
entry->maptype != VM_MAPTYPE_VPAGETABLE) {
continue;
}
obj = entry->object.vm_object;
if (obj)
vm_object_hold(obj);
if (obj && (obj->shadow_count == 1))
privateresident = obj->resident_page_count;
else
privateresident = 0;
/*
* Use map->hint as a poor man's ripout detector.
*/
map->hint = entry;
ostart = entry->start;
/*
* Count resident pages (XXX can be horrible on 64-bit)
*/
resident = 0;
addr = entry->start;
while (addr < entry->end) {
if (pmap_extract(pmap, addr))
resident++;
addr += PAGE_SIZE;
}
if (obj) {
lobj = obj;
while ((tobj = lobj->backing_object) != NULL) {
KKASSERT(tobj != obj);
vm_object_hold(tobj);
if (tobj == lobj->backing_object) {
if (lobj != obj) {
vm_object_lock_swap();
vm_object_drop(lobj);
}
lobj = tobj;
} else {
vm_object_drop(tobj);
}
}
} else {
lobj = NULL;
}
freepath = NULL;
fullpath = "-";
if (lobj) {
switch(lobj->type) {
default:
case OBJT_DEFAULT:
type = "default";
vp = NULL;
break;
case OBJT_VNODE:
type = "vnode";
vp = lobj->handle;
vref(vp);
break;
case OBJT_SWAP:
type = "swap";
vp = NULL;
break;
case OBJT_DEVICE:
type = "device";
vp = NULL;
break;
}
flags = obj->flags;
ref_count = obj->ref_count;
shadow_count = obj->shadow_count;
if (vp != NULL) {
vn_fullpath(p, vp, &fullpath, &freepath, 1);
vrele(vp);
}
if (lobj != obj)
vm_object_drop(lobj);
} else {
type = "none";
flags = 0;
ref_count = 0;
shadow_count = 0;
}
/*
* format:
* start, end, res, priv res, cow, access, type, (fullpath).
*/
ksnprintf(mebuffer, sizeof(mebuffer),
#if LONG_BIT == 64
"0x%016lx 0x%016lx %d %d %p %s%s%s %d %d "
#else
"0x%08lx 0x%08lx %d %d %p %s%s%s %d %d "
#endif
"0x%04x %s %s %s %s\n",
(u_long)entry->start, (u_long)entry->end,
resident, privateresident, obj,
(entry->protection & VM_PROT_READ)?"r":"-",
(entry->protection & VM_PROT_WRITE)?"w":"-",
(entry->protection & VM_PROT_EXECUTE)?"x":"-",
ref_count, shadow_count, flags,
(entry->eflags & MAP_ENTRY_COW)?"COW":"NCOW",
(entry->eflags & MAP_ENTRY_NEEDS_COPY)?"NC":"NNC",
type, fullpath);
if (obj)
vm_object_drop(obj);
if (freepath != NULL) {
kfree(freepath, M_TEMP);
freepath = NULL;
}
len = strlen(mebuffer);
if (len > uio->uio_resid) {
error = EFBIG;
break;
}
/*
* We cannot safely hold the map locked while accessing
* userspace as a VM fault might recurse the locked map.
*/
vm_map_unlock_read(map);
error = uiomove(mebuffer, len, uio);
vm_map_lock_read(map);
if (error)
break;
/*
* We use map->hint as a poor man's ripout detector. If
* it does not match the entry we set it to prior to
* unlocking the map the entry MIGHT now be stale. In
* this case we do an expensive lookup to find our place
* in the iteration again.
*/
if (map->hint != entry) {
vm_map_entry_t reentry;
vm_map_lookup_entry(map, ostart, &reentry);
entry = reentry;
}
}
vm_map_unlock_read(map);
return error;
}
/*
* Lets the VM system know about a change in size for a file.
* We adjust our own internal size and flush any cached pages in
* the associated object that are affected by the size change.
*
* NOTE: This routine may be invoked as a result of a pager put
* operation (possibly at object termination time), so we must be careful.
*
* NOTE: vp->v_filesize is initialized to NOOFFSET (-1), be sure that
* we do not blow up on the case. nsize will always be >= 0, however.
*/
void
vnode_pager_setsize(struct vnode *vp, vm_ooffset_t nsize)
{
vm_pindex_t nobjsize;
vm_pindex_t oobjsize;
vm_object_t object;
object = vp->v_object;
if (object == NULL)
return;
vm_object_hold(object);
KKASSERT(vp->v_object == object);
/*
* Hasn't changed size
*/
if (nsize == vp->v_filesize) {
vm_object_drop(object);
return;
}
/*
* Has changed size. Adjust the VM object's size and v_filesize
* before we start scanning pages to prevent new pages from being
* allocated during the scan.
*/
nobjsize = OFF_TO_IDX(nsize + PAGE_MASK);
oobjsize = object->size;
object->size = nobjsize;
/*
* File has shrunk. Toss any cached pages beyond the new EOF.
*/
if (nsize < vp->v_filesize) {
vp->v_filesize = nsize;
if (nobjsize < oobjsize) {
vm_object_page_remove(object, nobjsize, oobjsize,
FALSE);
}
/*
* This gets rid of garbage at the end of a page that is now
* only partially backed by the vnode. Since we are setting
* the entire page valid & clean after we are done we have
* to be sure that the portion of the page within the file
* bounds is already valid. If it isn't then making it
* valid would create a corrupt block.
*/
if (nsize & PAGE_MASK) {
vm_offset_t kva;
vm_page_t m;
m = vm_page_lookup_busy_wait(object, OFF_TO_IDX(nsize),
TRUE, "vsetsz");
if (m && m->valid) {
int base = (int)nsize & PAGE_MASK;
int size = PAGE_SIZE - base;
struct lwbuf *lwb;
struct lwbuf lwb_cache;
/*
* Clear out partial-page garbage in case
* the page has been mapped.
*
* This is byte aligned.
*/
lwb = lwbuf_alloc(m, &lwb_cache);
kva = lwbuf_kva(lwb);
bzero((caddr_t)kva + base, size);
lwbuf_free(lwb);
/*
* XXX work around SMP data integrity race
* by unmapping the page from user processes.
* The garbage we just cleared may be mapped
* to a user process running on another cpu
* and this code is not running through normal
* I/O channels which handle SMP issues for
* us, so unmap page to synchronize all cpus.
*
* XXX should vm_pager_unmap_page() have
* dealt with this?
*/
vm_page_protect(m, VM_PROT_NONE);
/*
* Clear out partial-page dirty bits. This
* has the side effect of setting the valid
* bits, but that is ok. There are a bunch
* of places in the VM system where we expected
* m->dirty == VM_PAGE_BITS_ALL. The file EOF
* case is one of them. If the page is still
* partially dirty, make it fully dirty.
*
* NOTE: We do not clear out the valid
* bits. This would prevent bogus_page
* replacement from working properly.
*
* NOTE: We do not want to clear the dirty
* bit for a partial DEV_BSIZE'd truncation!
* This is DEV_BSIZE aligned!
*/
vm_page_clear_dirty_beg_nonincl(m, base, size);
if (m->dirty != 0)
m->dirty = VM_PAGE_BITS_ALL;
vm_page_wakeup(m);
} else if (m) {
vm_page_wakeup(m);
}
}
} else {
vp->v_filesize = nsize;
}
vm_object_drop(object);
}
/*
* Allocate a VM object for a vnode, typically a regular file vnode.
*
* Some additional information is required to generate a properly sized
* object which covers the entire buffer cache buffer straddling the file
* EOF. Userland does not see the extra pages as the VM fault code tests
* against v_filesize.
*/
vm_object_t
vnode_pager_alloc(void *handle, off_t length, vm_prot_t prot, off_t offset,
int blksize, int boff)
{
vm_object_t object;
struct vnode *vp;
off_t loffset;
vm_pindex_t lsize;
/*
* Pageout to vnode, no can do yet.
*/
if (handle == NULL)
return (NULL);
/*
* XXX hack - This initialization should be put somewhere else.
*/
if (vnode_pbuf_freecnt < 0) {
vnode_pbuf_freecnt = nswbuf / 2 + 1;
}
/*
* Serialize potential vnode/object teardowns and interlocks
*/
vp = (struct vnode *)handle;
lwkt_gettoken(&vp->v_token);
/*
* If the object is being terminated, wait for it to
* go away.
*/
object = vp->v_object;
if (object) {
vm_object_hold(object);
KKASSERT((object->flags & OBJ_DEAD) == 0);
}
if (VREFCNT(vp) <= 0)
panic("vnode_pager_alloc: no vnode reference");
/*
* Round up to the *next* block, then destroy the buffers in question.
* Since we are only removing some of the buffers we must rely on the
* scan count to determine whether a loop is necessary.
*
* Destroy any pages beyond the last buffer.
*/
if (boff < 0)
boff = (int)(length % blksize);
if (boff)
loffset = length + (blksize - boff);
else
loffset = length;
lsize = OFF_TO_IDX(round_page64(loffset));
if (object == NULL) {
/*
* And an object of the appropriate size
*/
object = vm_object_allocate_hold(OBJT_VNODE, lsize);
object->handle = handle;
vp->v_object = object;
vp->v_filesize = length;
if (vp->v_mount && (vp->v_mount->mnt_kern_flag & MNTK_NOMSYNC))
vm_object_set_flag(object, OBJ_NOMSYNC);
vref(vp);
} else {
vm_object_reference_quick(object); /* also vref's */
if (object->size != lsize) {
kprintf("vnode_pager_alloc: Warning, objsize "
"mismatch %jd/%jd vp=%p obj=%p\n",
(intmax_t)object->size,
(intmax_t)lsize,
vp, object);
}
if (vp->v_filesize != length) {
kprintf("vnode_pager_alloc: Warning, filesize "
"mismatch %jd/%jd vp=%p obj=%p\n",
(intmax_t)vp->v_filesize,
(intmax_t)length,
vp, object);
}
}
vm_object_drop(object);
lwkt_reltoken(&vp->v_token);
return (object);
}
/*
* vm_contig_pg_kmap:
*
* Map previously allocated (vm_contig_pg_alloc) range of pages from
* vm_page_array[] into the KVA. Once mapped, the pages are part of
* the Kernel, and are to free'ed with kmem_free(&kernel_map, addr, size).
*
* No requirements.
*/
vm_offset_t
vm_contig_pg_kmap(int start, u_long size, vm_map_t map, int flags)
{
vm_offset_t addr, tmp_addr;
vm_page_t pga = vm_page_array;
int i, count;
size = round_page(size);
if (size == 0)
panic("vm_contig_pg_kmap: size must not be 0");
crit_enter();
lwkt_gettoken(&vm_token);
/*
* We've found a contiguous chunk that meets our requirements.
* Allocate KVM, and assign phys pages and return a kernel VM
* pointer.
*/
count = vm_map_entry_reserve(MAP_RESERVE_COUNT);
vm_map_lock(map);
if (vm_map_findspace(map, vm_map_min(map), size, PAGE_SIZE, 0, &addr) !=
KERN_SUCCESS) {
/*
* XXX We almost never run out of kernel virtual
* space, so we don't make the allocated memory
* above available.
*/
vm_map_unlock(map);
vm_map_entry_release(count);
lwkt_reltoken(&vm_token);
crit_exit();
return (0);
}
/*
* kernel_object maps 1:1 to kernel_map.
*/
vm_object_hold(&kernel_object);
vm_object_reference(&kernel_object);
vm_map_insert(map, &count,
&kernel_object, addr,
addr, addr + size,
VM_MAPTYPE_NORMAL,
VM_PROT_ALL, VM_PROT_ALL,
0);
vm_map_unlock(map);
vm_map_entry_release(count);
tmp_addr = addr;
for (i = start; i < (start + size / PAGE_SIZE); i++) {
vm_page_t m = &pga[i];
vm_page_insert(m, &kernel_object, OFF_TO_IDX(tmp_addr));
if ((flags & M_ZERO) && !(m->flags & PG_ZERO))
pmap_zero_page(VM_PAGE_TO_PHYS(m));
m->flags = 0;
tmp_addr += PAGE_SIZE;
}
vm_map_wire(map, addr, addr + size, 0);
vm_object_drop(&kernel_object);
lwkt_reltoken(&vm_token);
crit_exit();
return (addr);
}
/*
* vm_contig_pg_clean:
*
* Do a thorough cleanup of the specified 'queue', which can be either
* PQ_ACTIVE or PQ_INACTIVE by doing a walkthrough. If the page is not
* marked dirty, it is shoved into the page cache, provided no one has
* currently aqcuired it, otherwise localized action per object type
* is taken for cleanup:
*
* In the OBJT_VNODE case, the whole page range is cleaned up
* using the vm_object_page_clean() routine, by specyfing a
* start and end of '0'.
*
* Otherwise if the object is of any other type, the generic
* pageout (daemon) flush routine is invoked.
*/
static void
vm_contig_pg_clean(int queue, int count)
{
vm_object_t object;
vm_page_t m, m_tmp;
struct vm_page marker;
struct vpgqueues *pq = &vm_page_queues[queue];
/*
* Setup a local marker
*/
bzero(&marker, sizeof(marker));
marker.flags = PG_BUSY | PG_FICTITIOUS | PG_MARKER;
marker.queue = queue;
marker.wire_count = 1;
vm_page_queues_spin_lock(queue);
TAILQ_INSERT_HEAD(&pq->pl, &marker, pageq);
vm_page_queues_spin_unlock(queue);
/*
* Iterate the queue. Note that the vm_page spinlock must be
* acquired before the pageq spinlock so it's easiest to simply
* not hold it in the loop iteration.
*/
while (count-- > 0 && (m = TAILQ_NEXT(&marker, pageq)) != NULL) {
vm_page_and_queue_spin_lock(m);
if (m != TAILQ_NEXT(&marker, pageq)) {
vm_page_and_queue_spin_unlock(m);
++count;
continue;
}
KKASSERT(m->queue == queue);
TAILQ_REMOVE(&pq->pl, &marker, pageq);
TAILQ_INSERT_AFTER(&pq->pl, m, &marker, pageq);
if (m->flags & PG_MARKER) {
vm_page_and_queue_spin_unlock(m);
continue;
}
if (vm_page_busy_try(m, TRUE)) {
vm_page_and_queue_spin_unlock(m);
continue;
}
vm_page_and_queue_spin_unlock(m);
/*
* We've successfully busied the page
*/
if (m->queue - m->pc != queue) {
vm_page_wakeup(m);
continue;
}
if (m->wire_count || m->hold_count) {
vm_page_wakeup(m);
continue;
}
if ((object = m->object) == NULL) {
vm_page_wakeup(m);
continue;
}
vm_page_test_dirty(m);
if (m->dirty || (m->flags & PG_NEED_COMMIT)) {
vm_object_hold(object);
KKASSERT(m->object == object);
if (object->type == OBJT_VNODE) {
vm_page_wakeup(m);
vn_lock(object->handle, LK_EXCLUSIVE|LK_RETRY);
vm_object_page_clean(object, 0, 0, OBJPC_SYNC);
vn_unlock(((struct vnode *)object->handle));
} else if (object->type == OBJT_SWAP ||
object->type == OBJT_DEFAULT) {
m_tmp = m;
vm_pageout_flush(&m_tmp, 1, 0);
} else {
vm_page_wakeup(m);
}
vm_object_drop(object);
} else if (m->hold_count == 0) {
vm_page_cache(m);
} else {
vm_page_wakeup(m);
}
}
/*
* Scrap our local marker
*/
vm_page_queues_spin_lock(queue);
TAILQ_REMOVE(&pq->pl, &marker, pageq);
vm_page_queues_spin_unlock(queue);
}
/*
* A VFS can call this function to try to dispose of a read request
* directly from the VM system, pretty much bypassing almost all VFS
* overhead except for atime updates.
*
* If 0 is returned some or all of the uio was handled. The caller must
* check the uio and handle the remainder.
*
* The caller must fail on a non-zero error.
*/
int
vop_helper_read_shortcut(struct vop_read_args *ap)
{
struct vnode *vp;
struct uio *uio;
struct lwbuf *lwb;
struct lwbuf lwb_cache;
vm_object_t obj;
vm_page_t m;
int offset;
int n;
int error;
vp = ap->a_vp;
uio = ap->a_uio;
/*
* We can't short-cut if there is no VM object or this is a special
* UIO_NOCOPY read (typically from VOP_STRATEGY()). We also can't
* do this if we cannot extract the filesize from the vnode.
*/
if (vm_read_shortcut_enable == 0)
return(0);
if (vp->v_object == NULL || uio->uio_segflg == UIO_NOCOPY)
return(0);
if (vp->v_filesize == NOOFFSET)
return(0);
if (uio->uio_resid == 0)
return(0);
/*
* Iterate the uio on a page-by-page basis
*
* XXX can we leave the object held shared during the uiomove()?
*/
++vm_read_shortcut_count;
obj = vp->v_object;
vm_object_hold_shared(obj);
error = 0;
while (uio->uio_resid && error == 0) {
offset = (int)uio->uio_offset & PAGE_MASK;
n = PAGE_SIZE - offset;
if (n > uio->uio_resid)
n = uio->uio_resid;
if (vp->v_filesize < uio->uio_offset)
break;
if (uio->uio_offset + n > vp->v_filesize)
n = vp->v_filesize - uio->uio_offset;
if (n == 0)
break; /* hit EOF */
m = vm_page_lookup_busy_try(obj, OFF_TO_IDX(uio->uio_offset),
FALSE, &error);
if (error || m == NULL) {
++vm_read_shortcut_failed;
error = 0;
break;
}
if ((m->valid & VM_PAGE_BITS_ALL) != VM_PAGE_BITS_ALL) {
++vm_read_shortcut_failed;
vm_page_wakeup(m);
break;
}
lwb = lwbuf_alloc(m, &lwb_cache);
/*
* Use a no-fault uiomove() to avoid deadlocking against
* our VM object (which could livelock on the same object
* due to shared-vs-exclusive), or deadlocking against
* our busied page. Returns EFAULT on any fault which
* winds up diving a vnode.
*/
error = uiomove_nofault((char *)lwbuf_kva(lwb) + offset,
n, uio);
vm_page_flag_set(m, PG_REFERENCED);
lwbuf_free(lwb);
vm_page_wakeup(m);
}
vm_object_drop(obj);
/*
* Ignore EFAULT since we used uiomove_nofault(), causes caller
* to fall-back to normal code for this case.
*/
if (error == EFAULT)
error = 0;
return (error);
}
static int
link_elf_load_file(const char* filename, linker_file_t* result)
{
struct nlookupdata nd;
struct thread *td = curthread; /* XXX */
struct proc *p = td->td_proc;
struct vnode *vp;
Elf_Ehdr *hdr;
caddr_t firstpage;
int nbytes, i;
Elf_Phdr *phdr;
Elf_Phdr *phlimit;
Elf_Phdr *segs[2];
int nsegs;
Elf_Phdr *phdyn;
Elf_Phdr *phphdr;
caddr_t mapbase;
size_t mapsize;
Elf_Off base_offset;
Elf_Addr base_vaddr;
Elf_Addr base_vlimit;
int error = 0;
int resid;
elf_file_t ef;
linker_file_t lf;
char *pathname;
Elf_Shdr *shdr;
int symtabindex;
int symstrindex;
int symcnt;
int strcnt;
/* XXX Hack for firmware loading where p == NULL */
if (p == NULL) {
p = &proc0;
}
KKASSERT(p != NULL);
if (p->p_ucred == NULL) {
kprintf("link_elf_load_file: cannot load '%s' from filesystem"
" this early\n", filename);
return ENOENT;
}
shdr = NULL;
lf = 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.
*/
firstpage = kmalloc(PAGE_SIZE, M_LINKER, M_WAITOK);
hdr = (Elf_Ehdr *)firstpage;
error = vn_rdwr(UIO_READ, vp, firstpage, PAGE_SIZE, 0,
UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
nbytes = PAGE_SIZE - resid;
if (error)
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_error("Unsupported file layout");
error = ENOEXEC;
goto out;
}
if (hdr->e_ident[EI_VERSION] != EV_CURRENT
|| hdr->e_version != EV_CURRENT) {
link_elf_error("Unsupported file version");
error = ENOEXEC;
goto out;
}
if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN) {
error = ENOSYS;
goto out;
}
if (hdr->e_machine != ELF_TARG_MACH) {
link_elf_error("Unsupported machine");
error = ENOEXEC;
goto out;
}
/*
* We rely on the program header being in the first page. This is
* not strictly required by the ABI specification, but it seems to
* always true in practice. And, it simplifies things considerably.
*/
if (!((hdr->e_phentsize == sizeof(Elf_Phdr)) &&
(hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= PAGE_SIZE) &&
(hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= nbytes)))
link_elf_error("Unreadable program headers");
/*
* Scan the program header entries, and save key information.
*
* We rely on there being exactly two load segments, text and data,
* in that order.
*/
phdr = (Elf_Phdr *) (firstpage + hdr->e_phoff);
phlimit = phdr + hdr->e_phnum;
nsegs = 0;
phdyn = NULL;
phphdr = NULL;
while (phdr < phlimit) {
switch (phdr->p_type) {
case PT_LOAD:
if (nsegs == 2) {
link_elf_error("Too many sections");
error = ENOEXEC;
goto out;
}
segs[nsegs] = phdr;
++nsegs;
break;
case PT_PHDR:
phphdr = phdr;
break;
case PT_DYNAMIC:
phdyn = phdr;
break;
case PT_INTERP:
error = ENOSYS;
goto out;
}
++phdr;
}
if (phdyn == NULL) {
link_elf_error("Object is not dynamically-linked");
error = ENOEXEC;
goto out;
}
/*
* Allocate the entire address space of the object, to stake out our
* contiguous region, and to establish the base address for relocation.
*/
base_offset = trunc_page(segs[0]->p_offset);
base_vaddr = trunc_page(segs[0]->p_vaddr);
base_vlimit = round_page(segs[1]->p_vaddr + segs[1]->p_memsz);
mapsize = base_vlimit - base_vaddr;
ef = kmalloc(sizeof(struct elf_file), M_LINKER, M_WAITOK | M_ZERO);
#ifdef SPARSE_MAPPING
ef->object = vm_object_allocate(OBJT_DEFAULT, mapsize >> PAGE_SHIFT);
if (ef->object == NULL) {
kfree(ef, M_LINKER);
error = ENOMEM;
goto out;
}
vm_object_hold(ef->object);
vm_object_reference_locked(ef->object);
ef->address = (caddr_t)vm_map_min(&kernel_map);
error = vm_map_find(&kernel_map, ef->object, 0,
(vm_offset_t *)&ef->address,
mapsize, PAGE_SIZE,
1, VM_MAPTYPE_NORMAL,
VM_PROT_ALL, VM_PROT_ALL,
0);
vm_object_drop(ef->object);
if (error) {
vm_object_deallocate(ef->object);
kfree(ef, M_LINKER);
goto out;
}
#else
ef->address = kmalloc(mapsize, M_LINKER, M_WAITOK);
#endif
mapbase = ef->address;
/*
* Read the text and data sections and zero the bss.
*/
for (i = 0; i < 2; i++) {
caddr_t segbase = mapbase + segs[i]->p_vaddr - base_vaddr;
error = vn_rdwr(UIO_READ, vp,
segbase, segs[i]->p_filesz, segs[i]->p_offset,
UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
if (error) {
#ifdef SPARSE_MAPPING
vm_map_remove(&kernel_map, (vm_offset_t) ef->address,
(vm_offset_t) ef->address
+ (ef->object->size << PAGE_SHIFT));
vm_object_deallocate(ef->object);
#else
kfree(ef->address, M_LINKER);
#endif
kfree(ef, M_LINKER);
goto out;
}
bzero(segbase + segs[i]->p_filesz,
segs[i]->p_memsz - segs[i]->p_filesz);
#ifdef SPARSE_MAPPING
/*
* Wire down the pages
*/
vm_map_wire(&kernel_map,
(vm_offset_t) segbase,
(vm_offset_t) segbase + segs[i]->p_memsz,
0);
#endif
}
ef->dynamic = (const Elf_Dyn *) (mapbase + phdyn->p_vaddr - base_vaddr);
lf = linker_make_file(filename, ef, &link_elf_file_ops);
if (lf == NULL) {
#ifdef SPARSE_MAPPING
vm_map_remove(&kernel_map, (vm_offset_t) ef->address,
(vm_offset_t) ef->address
+ (ef->object->size << PAGE_SHIFT));
vm_object_deallocate(ef->object);
#else
kfree(ef->address, M_LINKER);
#endif
kfree(ef, M_LINKER);
error = ENOMEM;
goto out;
}
lf->address = ef->address;
lf->size = mapsize;
error = parse_dynamic(lf);
if (error)
goto out;
link_elf_reloc_local(lf);
error = linker_load_dependencies(lf);
if (error)
goto out;
error = relocate_file(lf);
if (error)
goto out;
/* Try and load the symbol table if it's present. (you can strip it!) */
nbytes = hdr->e_shnum * hdr->e_shentsize;
if (nbytes == 0 || hdr->e_shoff == 0)
goto nosyms;
shdr = kmalloc(nbytes, M_LINKER, M_WAITOK | M_ZERO);
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;
symtabindex = -1;
symstrindex = -1;
for (i = 0; i < hdr->e_shnum; i++) {
if (shdr[i].sh_type == SHT_SYMTAB) {
symtabindex = i;
symstrindex = shdr[i].sh_link;
}
}
if (symtabindex < 0 || symstrindex < 0)
goto nosyms;
symcnt = shdr[symtabindex].sh_size;
ef->symbase = kmalloc(symcnt, M_LINKER, M_WAITOK);
strcnt = shdr[symstrindex].sh_size;
ef->strbase = kmalloc(strcnt, M_LINKER, M_WAITOK);
error = vn_rdwr(UIO_READ, vp,
ef->symbase, symcnt, shdr[symtabindex].sh_offset,
UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
if (error)
goto out;
error = vn_rdwr(UIO_READ, vp,
ef->strbase, strcnt, shdr[symstrindex].sh_offset,
UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
if (error)
goto out;
ef->ddbsymcnt = symcnt / sizeof(Elf_Sym);
ef->ddbsymtab = (const Elf_Sym *)ef->symbase;
ef->ddbstrcnt = strcnt;
ef->ddbstrtab = ef->strbase;
nosyms:
*result = lf;
out:
if (error && lf)
linker_file_unload(lf);
if (shdr)
kfree(shdr, M_LINKER);
if (firstpage)
kfree(firstpage, M_LINKER);
vn_unlock(vp);
vn_close(vp, FREAD);
return error;
}
