Differential D26394 Diff 76907 head/sys/kern/uipc_shm.c

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head/sys/kern/uipc_shm.c

Show First 20 Lines • Show All 444 Lines • ▼ Show 20 Lines	rl_cookie = rangelock_wlock(&shmfd->shm_rl, uio->uio_offset,
size, &shmfd->shm_mtx);		size, &shmfd->shm_mtx);
}		}
if ((shmfd->shm_seals & F_SEAL_WRITE) != 0) {		if ((shmfd->shm_seals & F_SEAL_WRITE) != 0) {
error = EPERM;		error = EPERM;
} else {		} else {
error = 0;		error = 0;
if ((shmfd->shm_flags & SHM_GROW_ON_WRITE) != 0 &&		if ((shmfd->shm_flags & SHM_GROW_ON_WRITE) != 0 &&
size > shmfd->shm_size) {		size > shmfd->shm_size) {
VM_OBJECT_WLOCK(shmfd->shm_object);		error = shm_dotruncate_cookie(shmfd, size, rl_cookie);
error = shm_dotruncate_locked(shmfd, size, rl_cookie);
VM_OBJECT_WUNLOCK(shmfd->shm_object);
}		}
if (error == 0)		if (error == 0)
error = uiomove_object(shmfd->shm_object,		error = uiomove_object(shmfd->shm_object,
shmfd->shm_size, uio);		shmfd->shm_size, uio);
}		}
rangelock_unlock(&shmfd->shm_rl, rl_cookie, &shmfd->shm_mtx);		rangelock_unlock(&shmfd->shm_rl, rl_cookie, &shmfd->shm_mtx);
foffset_unlock_uio(fp, uio, flags);		foffset_unlock_uio(fp, uio, flags);
return (error);		return (error);
▲ Show 20 Lines • Show All 298 Lines • ▼ Show 20 Lines
#if 0		#if 0
vm_object_page_remove(object, newobjsz, oldobjsz, 0);		vm_object_page_remove(object, newobjsz, oldobjsz, 0);
object->size = newobjsz;		object->size = newobjsz;
shmfd->shm_size = length;		shmfd->shm_size = length;
return (0);		return (0);
#endif		#endif
}		}

		if ((shmfd->shm_seals & F_SEAL_GROW) != 0)
		return (EPERM);

aflags = VM_ALLOC_NORMAL \| VM_ALLOC_ZERO;		aflags = VM_ALLOC_NORMAL \| VM_ALLOC_ZERO;
if (shmfd->shm_lp_alloc_policy == SHM_LARGEPAGE_ALLOC_NOWAIT)		if (shmfd->shm_lp_alloc_policy == SHM_LARGEPAGE_ALLOC_NOWAIT)
aflags \|= VM_ALLOC_WAITFAIL;		aflags \|= VM_ALLOC_WAITFAIL;
try = 0;		try = 0;

/*		/*
* Extend shmfd and object, keeping all already fully		* Extend shmfd and object, keeping all already fully
* allocated large pages intact even on error, because dropped		* allocated large pages intact even on error, because dropped
▲ Show 20 Lines • Show All 633 Lines • ▼ Show 20 Lines	out:
free(path_from, M_SHMFD);		free(path_from, M_SHMFD);
free(path_to, M_SHMFD);		free(path_to, M_SHMFD);
return (error);		return (error);
}		}

static int		static int
shm_mmap_large(struct shmfd shmfd, vm_map_t map, vm_offset_t addr,		shm_mmap_large(struct shmfd shmfd, vm_map_t map, vm_offset_t addr,
vm_size_t size, vm_prot_t prot, vm_prot_t max_prot, int flags,		vm_size_t size, vm_prot_t prot, vm_prot_t max_prot, int flags,
vm_ooffset_t foff, bool writecounted, struct thread *td)		vm_ooffset_t foff, struct thread *td)
{		{
struct vmspace *vms;		struct vmspace *vms;
vm_map_entry_t next_entry, prev_entry;		vm_map_entry_t next_entry, prev_entry;
vm_offset_t align, mask, maxaddr;		vm_offset_t align, mask, maxaddr;
int docow, error, rv, try;		int docow, error, rv, try;
bool curmap;		bool curmap;

if (shmfd->shm_lp_psind == 0)		if (shmfd->shm_lp_psind == 0)
Show All 15 Lines	if (curmap) {
if (error != 0)		if (error != 0)
return (error);		return (error);
}		}

docow = shmfd->shm_lp_psind << MAP_SPLIT_BOUNDARY_SHIFT;		docow = shmfd->shm_lp_psind << MAP_SPLIT_BOUNDARY_SHIFT;
docow \|= MAP_INHERIT_SHARE;		docow \|= MAP_INHERIT_SHARE;
if ((flags & MAP_NOCORE) != 0)		if ((flags & MAP_NOCORE) != 0)
docow \|= MAP_DISABLE_COREDUMP;		docow \|= MAP_DISABLE_COREDUMP;
if (writecounted)
docow \|= MAP_WRITECOUNT;

mask = pagesizes[shmfd->shm_lp_psind] - 1;		mask = pagesizes[shmfd->shm_lp_psind] - 1;
if ((foff & mask) != 0)		if ((foff & mask) != 0)
return (EINVAL);		return (EINVAL);
maxaddr = vm_map_max(map);		maxaddr = vm_map_max(map);
#ifdef MAP_32BIT		#ifdef MAP_32BIT
if ((flags & MAP_32BIT) != 0 && maxaddr > MAP_32BIT_MAX_ADDR)		if ((flags & MAP_32BIT) != 0 && maxaddr > MAP_32BIT_MAX_ADDR)
maxaddr = MAP_32BIT_MAX_ADDR;		maxaddr = MAP_32BIT_MAX_ADDR;
▲ Show 20 Lines • Show All 128 Lines • ▼ Show 20 Lines	if (error != 0)
goto out;		goto out;
#endif		#endif

mtx_lock(&shm_timestamp_lock);		mtx_lock(&shm_timestamp_lock);
vfs_timestamp(&shmfd->shm_atime);		vfs_timestamp(&shmfd->shm_atime);
mtx_unlock(&shm_timestamp_lock);		mtx_unlock(&shm_timestamp_lock);
vm_object_reference(shmfd->shm_object);		vm_object_reference(shmfd->shm_object);

if (writecnt)
vm_pager_update_writecount(shmfd->shm_object, 0, objsize);
if (shm_largepage(shmfd)) {		if (shm_largepage(shmfd)) {
		writecnt = false;
error = shm_mmap_large(shmfd, map, addr, objsize, prot,		error = shm_mmap_large(shmfd, map, addr, objsize, prot,
maxprot, flags, foff, writecnt, td);		maxprot, flags, foff, td);
} else {		} else {
		if (writecnt) {
		vm_pager_update_writecount(shmfd->shm_object, 0,
		objsize);
		}
error = vm_mmap_object(map, addr, objsize, prot, maxprot, flags,		error = vm_mmap_object(map, addr, objsize, prot, maxprot, flags,
shmfd->shm_object, foff, writecnt, td);		shmfd->shm_object, foff, writecnt, td);
}		}
if (error != 0) {		if (error != 0) {
if (writecnt)		if (writecnt)
vm_pager_release_writecount(shmfd->shm_object, 0,		vm_pager_release_writecount(shmfd->shm_object, 0,
objsize);		objsize);
vm_object_deallocate(shmfd->shm_object);		vm_object_deallocate(shmfd->shm_object);
▲ Show 20 Lines • Show All 222 Lines • ▼ Show 20 Lines	shm_add_seals(struct file *fp, int seals)

/* Even already-set seals should result in EPERM. */		/* Even already-set seals should result in EPERM. */
if ((shmfd->shm_seals & F_SEAL_SEAL) != 0) {		if ((shmfd->shm_seals & F_SEAL_SEAL) != 0) {
error = EPERM;		error = EPERM;
goto out;		goto out;
}		}
nseals = seals & ~shmfd->shm_seals;		nseals = seals & ~shmfd->shm_seals;
if ((nseals & F_SEAL_WRITE) != 0) {		if ((nseals & F_SEAL_WRITE) != 0) {
		if (shm_largepage(shmfd)) {
		error = ENOTSUP;
		goto out;
		}

/*		/*
* The rangelock above prevents writable mappings from being		* The rangelock above prevents writable mappings from being
* added after we've started applying seals. The RLOCK here		* added after we've started applying seals. The RLOCK here
* is to avoid torn reads on ILP32 arches as unmapping/reducing		* is to avoid torn reads on ILP32 arches as unmapping/reducing
* writemappings will be done without a rangelock.		* writemappings will be done without a rangelock.
*/		*/
VM_OBJECT_RLOCK(shmfd->shm_object);		VM_OBJECT_RLOCK(shmfd->shm_object);
writemappings = shmfd->shm_object->un_pager.swp.writemappings;		writemappings = shmfd->shm_object->un_pager.swp.writemappings;
▲ Show 20 Lines • Show All 126 Lines • Show Last 20 Lines