litmus-rt.git - The LITMUS^RT kernel.

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The LITMUS^RT kernel.

Bjoern Brandenburg

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path: root/include/scsi/scsi_cmnd.h

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Diffstat (limited to 'include/scsi/scsi_cmnd.h')

-rw-r--r--

include/scsi/scsi_cmnd.h

1 files changed, 1 insertions, 1 deletions


diff --git a/include/scsi/scsi_cmnd.h b/include/scsi/scsi_cmnd.h index 43b50d36925c..3878d1dc7f59 100644 --- a/include/scsi/scsi_cmnd.h +++ b/include/scsi/scsi_cmnd.h
@@ -270,7 +270,7 @@ static inline unsigned char scsi_get_prot_type(struct scsi_cmnd *scmd)
270		270
271	static inline sector_t scsi_get_lba(struct scsi_cmnd *scmd)	271	static inline sector_t scsi_get_lba(struct scsi_cmnd *scmd)
272	{	272	{
273	return scmd->request->sector;	273	return blk_rq_pos(scmd->request);
274	}	274	}
275		275
276	static inline unsigned scsi_prot_sg_count(struct scsi_cmnd *cmd)	276	static inline unsigned scsi_prot_sg_count(struct scsi_cmnd *cmd)

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/*
 * mm/mmap.c
 *
 * Written by obz.
 *
 * Address space accounting code	<alan@lxorguk.ukuu.org.uk>
 */

#include <linux/slab.h>
#include <linux/backing-dev.h>
#include <linux/mm.h>
#include <linux/shm.h>
#include <linux/mman.h>
#include <linux/pagemap.h>
#include <linux/swap.h>
#include <linux/syscalls.h>
#include <linux/capability.h>
#include <linux/init.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/personality.h>
#include <linux/security.h>
#include <linux/hugetlb.h>
#include <linux/profile.h>
#include <linux/export.h>
#include <linux/mount.h>
#include <linux/mempolicy.h>
#include <linux/rmap.h>
#include <linux/mmu_notifier.h>
#include <linux/perf_event.h>
#include <linux/audit.h>
#include <linux/khugepaged.h>
#include <linux/uprobes.h>
#include <linux/rbtree_augmented.h>
#include <linux/sched/sysctl.h>

#include <asm/uaccess.h>
#include <asm/cacheflush.h>
#include <asm/tlb.h>
#include <asm/mmu_context.h>

#include "internal.h"

#ifndef arch_mmap_check
#define arch_mmap_check(addr, len, flags)	(0)
#endif

#ifndef arch_rebalance_pgtables
#define arch_rebalance_pgtables(addr, len)		(addr)
#endif

static void unmap_region(struct mm_struct *mm,
		struct vm_area_struct *vma, struct vm_area_struct *prev,
		unsigned long start, unsigned long end);

/* description of effects of mapping type and prot in current implementation.
 * this is due to the limited x86 page protection hardware.  The expected
 * behavior is in parens:
 *
 * map_type	prot
 *		PROT_NONE	PROT_READ	PROT_WRITE	PROT_EXEC
 * MAP_SHARED	r: (no) no	r: (yes) yes	r: (no) yes	r: (no) yes
 *		w: (no) no	w: (no) no	w: (yes) yes	w: (no) no
 *		x: (no) no	x: (no) yes	x: (no) yes	x: (yes) yes
 *		
 * MAP_PRIVATE	r: (no) no	r: (yes) yes	r: (no) yes	r: (no) yes
 *		w: (no) no	w: (no) no	w: (copy) copy	w: (no) no
 *		x: (no) no	x: (no) yes	x: (no) yes	x: (yes) yes
 *
 */
pgprot_t protection_map[16] = {
	__P000, __P001, __P010, __P011, __P100, __P101, __P110, __P111,
	__S000, __S001, __S010, __S011, __S100, __S101, __S110, __S111
};

pgprot_t vm_get_page_prot(unsigned long vm_flags)
{
	return __pgprot(pgprot_val(protection_map[vm_flags &
				(VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]) |
			pgprot_val(arch_vm_get_page_prot(vm_flags)));
}
EXPORT_SYMBOL(vm_get_page_prot);

int sysctl_overcommit_memory __read_mostly = OVERCOMMIT_GUESS;  /* heuristic overcommit */
int sysctl_overcommit_ratio __read_mostly = 50;	/* default is 50% */
int sysctl_max_map_count __read_mostly = DEFAULT_MAX_MAP_COUNT;
/*
 * Make sure vm_committed_as in one cacheline and not cacheline shared with
 * other variables. It can be updated by several CPUs frequently.
 */
struct percpu_counter vm_committed_as ____cacheline_aligned_in_smp;

/*
 * The global memory commitment made in the system can be a metric
 * that can be used to drive ballooning decisions when Linux is hosted
 * as a guest. On Hyper-V, the host implements a policy engine for dynamically
 * balancing memory across competing virtual machines that are hosted.
 * Several metrics drive this policy engine including the guest reported
 * memory commitment.
 */
unsigned long vm_memory_committed(void)
{
	return percpu_counter_read_positive(&vm_committed_as);
}
EXPORT_SYMBOL_GPL(vm_memory_committed);

/*
 * Check that a process has enough memory to allocate a new virtual
 * mapping. 0 means there is enough memory for the allocation to
 * succeed and -ENOMEM implies there is not.
 *
 * We currently support three overcommit policies, which are set via the
 * vm.overcommit_memory sysctl.  See Documentation/vm/overcommit-accounting
 *
 * Strict overcommit modes added 2002 Feb 26 by Alan Cox.
 * Additional code 2002 Jul 20 by Robert Love.
 *
 * cap_sys_admin is 1 if the process has admin privileges, 0 otherwise.
 *
 * Note this is a helper function intended to be used by LSMs which
 * wish to use this logic.
 */
int __vm_enough_memory(struct mm_struct *mm, long pages, int cap_sys_admin)
{
	unsigned long free, allowed;

	vm_acct_memory(pages);

	/*
	 * Sometimes we want to use more memory than we have
	 */
	if (sysctl_overcommit_memory == OVERCOMMIT_ALWAYS)
		return 0;

	if (sysctl_overcommit_memory == OVERCOMMIT_GUESS) {
		free = global_page_state(NR_FREE_PAGES);
		free += global_page_state(NR_FILE_PAGES);

		/*
		 * shmem pages shouldn't be counted as free in this
		 * case, they can't be purged, only swapped out, and
		 * that won't affect the overall amount of available
		 * memory in the system.
		 */
		free -= global_page_state(NR_SHMEM);

		free += get_nr_swap_pages();

		/*
		 * Any slabs which are created with the
		 * SLAB_RECLAIM_ACCOUNT flag claim to have contents
		 * which are reclaimable, under pressure.  The dentry
		 * cache and most inode caches should fall into this
		 */
		free += global_page_state(NR_SLAB_RECLAIMABLE);

		/*
		 * Leave reserved pages. The pages are not for anonymous pages.
		 */
		if (free <= totalreserve_pages)
			goto error;
		else
			free -= totalreserve_pages;

		/*
		 * Leave the last 3% for root
		 */
		if (!cap_sys_admin)
			free -= free / 32;

		if (free > pages)
			return 0;

		goto error;
	}

	allowed = (totalram_pages - hugetlb_total_pages())
	       	* sysctl_overcommit_ratio / 100;
	/*
	 * Leave the last 3% for root
	 */
	if (!cap_sys_admin)
		allowed -= allowed / 32;
	allowed += total_swap_pages;

	/* Don't let a single process grow too big:
	   leave 3% of the size of this process for other processes */
	if (mm)
		allowed -= mm->total_vm / 32;

	if (percpu_counter_read_positive(&vm_committed_as) < allowed)
		return 0;
error:
	vm_unacct_memory(pages);

	return -ENOMEM;
}

/*
 * Requires inode->i_mapping->i_mmap_mutex
 */
static void __remove_shared_vm_struct(struct vm_area_struct *vma,
		struct file *file, struct address_space *mapping)
{
	if (vma->vm_flags & VM_DENYWRITE)
		atomic_inc(&file_inode(file)->i_writecount);
	if (vma->vm_flags & VM_SHARED)
		mapping->i_mmap_writable--;

	flush_dcache_mmap_lock(mapping);
	if (unlikely(vma->vm_flags & VM_NONLINEAR))
		list_del_init(&vma->shared.nonlinear);
	else
		vma_interval_tree_remove(vma, &mapping->i_mmap);
	flush_dcache_mmap_unlock(mapping);
}

/*
 * Unlink a file-based vm structure from its interval tree, to hide
 * vma from rmap and vmtruncate before freeing its page tables.
 */
void unlink_file_vma(struct vm_area_struct *vma)
{
	struct file *file = vma->vm_file;

	if (file) {
		struct address_space *mapping = file->f_mapping;
		mutex_lock(&mapping->i_mmap_mutex);
		__remove_shared_vm_struct(vma, file, mapping);
		mutex_unlock(&mapping->i_mmap_mutex);
	}
}

/*
 * Close a vm structure and free it, returning the next.
 */
static struct vm_area_struct *remove_vma(struct vm_area_struct *vma)
{
	struct vm_area_struct *next = vma->vm_next;

	might_sleep();
	if (vma->vm_ops && vma->vm_ops->close)
		vma->vm_ops->close(vma);
	if (vma->vm_file)
		fput(vma->vm_file);
	mpol_put(vma_policy(vma));
	kmem_cache_free(vm_area_cachep, vma);
	return next;
}

static unsigned long do_brk(unsigned long addr, unsigned long len);

SYSCALL_DEFINE1(brk, unsigned long, brk)
{
	unsigned long rlim, retval;
	unsigned long newbrk, oldbrk;
	struct mm_struct *mm = current->mm;
	unsigned long min_brk;
	bool populate;

	down_write(&mm->mmap_sem);

#ifdef CONFIG_COMPAT_BRK
	/*
	 * CONFIG_COMPAT_BRK can still be overridden by setting
	 * randomize_va_space to 2, which will still cause mm->start_brk
	 * to be arbitrarily shifted
	 */
	if (current->brk_randomized)
		min_brk = mm->start_brk;
	else
		min_brk = mm->end_data;
#else
	min_brk = mm->start_brk;
#endif
	if (brk < min_brk)
		goto out;

	/*
	 * Check against rlimit here. If this check is done later after the test
	 * of oldbrk with newbrk then it can escape the test and let the data
	 * segment grow beyond its set limit the in case where the limit is
	 * not page aligned -Ram Gupta
	 */
	rlim = rlimit(RLIMIT_DATA);
	if (rlim < RLIM_INFINITY && (brk - mm->start_brk) +
			(mm->end_data - mm->start_data) > rlim)
		goto out;

	newbrk = PAGE_ALIGN(brk);
	oldbrk = PAGE_ALIGN(mm->brk);
	if (oldbrk == newbrk)
		goto set_brk;

	/* Always allow shrinking brk. */
	if (brk <= mm->brk) {
		if (!do_munmap(mm, newbrk, oldbrk-newbrk))
			goto set_brk;
		goto out;
	}

	/* Check against existing mmap mappings. */
	if (find_vma_intersection(mm, oldbrk, newbrk+PAGE_SIZE))
		goto out;

	/* Ok, looks good - let it rip. */
	if (do_brk(oldbrk, newbrk-oldbrk) != oldbrk)
		goto out;

set_brk:
	mm->brk = brk;
	populate = newbrk > oldbrk && (mm->def_flags & VM_LOCKED) != 0;
	up_write(&mm->mmap_sem);
	if (populate)
		mm_populate(oldbrk, newbrk - oldbrk);
	return brk;

out:
	retval = mm->brk;
	up_write(&mm->mmap_sem);
	return retval;
}

static long vma_compute_subtree_gap(struct vm_area_struct *vma)
{
	unsigned long max, subtree_gap;
	max = vma->vm_start;
	if (vma->vm_prev)
		max -= vma->vm_prev->vm_end;
	if (vma->vm_rb.rb_left) {
		subtree_gap = rb_entry(vma->vm_rb.rb_left,
				struct vm_area_struct, vm_rb)->rb_subtree_gap;
		if (subtree_gap > max)
			max = subtree_gap;
	}
	if (vma->vm_rb.rb_right) {
		subtree_gap = rb_entry(vma->vm_rb.rb_right,
				struct vm_area_struct, vm_rb)->rb_subtree_gap;
		if (subtree_gap > max)
			max = subtree_gap;
	}
	return max;
}

#ifdef CONFIG_DEBUG_VM_RB
static int browse_rb(struct rb_root *root)
{
	int i = 0, j, bug = 0;
	struct rb_node *nd, *pn = NULL;
	unsigned long prev = 0, pend = 0;

	for (nd = rb_first(root); nd; nd = rb_next(nd)) {
		struct vm_area_struct *vma;
		vma = rb_entry(nd, struct vm_area_struct, vm_rb);
		if (vma->vm_start < prev) {
			printk("vm_start %lx prev %lx\n", vma->vm_start, prev);
			bug = 1;
		}
		if (vma->vm_start < pend) {
			printk("vm_start %lx pend %lx\n", vma->vm_start, pend);
			bug = 1;
		}
		if (vma->vm_start > vma->vm_end) {
			printk("vm_end %lx < vm_start %lx\n",
				vma->vm_end, vma->vm_start);
			bug = 1;
		}
		if (vma->rb_subtree_gap != vma_compute_subtree_gap(vma)) {
			printk("free gap %lx, correct %lx\n",
			       vma->rb_subtree_gap,
			       vma_compute_subtree_gap(vma));
			bug = 1;
		}
		i++;
		pn = nd;
		prev = vma->vm_start;
		pend = vma->vm_end;
	}
	j = 0;
	for (nd = pn; nd; nd = rb_prev(nd))
		j++;
	if (i != j) {
		printk("backwards %d, forwards %d\n", j, i);
		bug = 1;
	}
	return bug ? -1 : i;
}

static void validate_mm_rb(struct rb_root *root, struct vm_area_struct *ignore)
{
	struct rb_node *nd;

	for (nd = rb_first(root); nd; nd = rb_next(nd)) {
		struct vm_area_struct *vma;
		vma = rb_entry(nd, struct vm_area_struct, vm_rb);
		BUG_ON(vma != ignore &&
		       vma->rb_subtree_gap != vma_compute_subtree_gap(vma));
	}
}

void validate_mm(struct mm_struct *mm)
{
	int bug = 0;
	int i = 0;
	unsigned long highest_address = 0;
	struct vm_area_struct *vma = mm->mmap;
	while (vma) {
		struct anon_vma_chain *avc;
		vma_lock_anon_vma(vma);
		list_for_each_entry(avc, &vma->anon_vma_chain, same_vma)
			anon_vma_interval_tree_verify(avc);
		vma_unlock_anon_vma(vma);
		highest_address = vma->vm_end;
		vma = vma->vm_next;
		i++;
	}
	if (i != mm->map_count) {
		printk("map_count %d vm_next %d\n", mm->map_count, i);
		bug = 1;
	}
	if (highest_address != mm->highest_vm_end) {
		printk("mm->highest_vm_end %lx, found %lx\n",
		       mm->highest_vm_end, highest_address);
		bug = 1;
	}
	i = browse_rb(&mm->mm_rb);
	if (i != mm->map_count) {
		printk("map_count %d rb %d\n", mm->map_count, i);
		bug = 1;
	}
	BUG_ON(bug);
}
#else
#define validate_mm_rb(root, ignore) do { } while (0)
#define validate_mm(mm) do { } while (0)
#endif

RB_DECLARE_CALLBACKS(static, vma_gap_callbacks, struct vm_area_struct, vm_rb,
		     unsigned long, rb_subtree_gap, vma_compute_subtree_gap)

/*
 * Update augmented rbtree rb_subtree_gap values after vma->vm_start or
 * vma->vm_prev->vm_end values changed, without modifying the vma's position
 * in the rbtree.
 */
static void vma_gap_update(struct vm_area_struct *vma)
{
	/*
	 * As it turns out, RB_DECLARE_CALLBACKS() already created a callback
	 * function that does exacltly what we want.
	 */
	vma_gap_callbacks_propagate(&vma->vm_rb, NULL);
}

static inline void vma_rb_insert(struct vm_area_struct *vma,
				 struct rb_root *root)
{
	/* All rb_subtree_gap values must be consistent prior to insertion */
	validate_mm_rb(root, NULL);

	rb_insert_augmented(&vma->vm_rb, root, &vma_gap_callbacks);
}

static void vma_rb_erase(struct vm_area_struct *vma, struct rb_root *root)
{
	/*
	 * All rb_subtree_gap values must be consistent prior to erase,
	 * with the possible exception of the vma being erased.
	 */
	validate_mm_rb(root, vma);

	/*
	 * Note rb_erase_augmented is a fairly large inline function,
	 * so make sure we instantiate it only once with our desired
	 * augmented rbtree callbacks.
	 */
	rb_erase_augmented(&vma->vm_rb, root, &vma_gap_callbacks);
}

/*
 * vma has some anon_vma assigned, and is already inserted on that
 * anon_vma's interval trees.
 *
 * Before updating the vma's vm_start / vm_end / vm_pgoff fields, the
 * vma must be removed from the anon_vma's interval trees using
 * anon_vma_interval_tree_pre_update_vma().
 *
 * After the update, the vma will be reinserted using
 * anon_vma_interval_tree_post_update_vma().
 *
 * The entire update must be protected by exclusive mmap_sem and by
 * the root anon_vma's mutex.
 */
static inline void
anon_vma_interval_tree_pre_update_vma(struct vm_area_struct *vma)
{
	struct anon_vma_chain *avc;

	list_for_each_entry(avc, &vma->anon_vma_chain, same_vma)
		anon_vma_interval_tree_remove(avc, &avc->anon_vma->rb_root);
}

static inline void
anon_vma_interval_tree_post_update_vma(struct vm_area_struct *vma)
{
	struct anon_vma_chain *avc;

	list_for_each_entry(avc, &vma->anon_vma_chain, same_vma)
		anon_vma_interval_tree_insert(avc, &avc->anon_vma->rb_root);
}

static int find_vma_links(struct mm_struct *mm, unsigned long addr,
		unsigned long end, struct vm_area_struct **pprev,
		struct rb_node ***rb_link, struct rb_node **rb_parent)
{
	struct rb_node **__rb_link, *__rb_parent, *rb_prev;

	__rb_link = &mm->mm_rb.rb_node;
	rb_prev = __rb_parent = NULL;

	while (*__rb_link) {
		struct vm_area_struct *vma_tmp;

		__rb_parent = *__rb_link;
		vma_tmp = rb_entry(__rb_parent, struct vm_area_struct, vm_rb);

		if (vma_tmp->vm_end > addr) {
			/* Fail if an existing vma overlaps the area */
			if (vma_tmp->vm_start < end)
				return -ENOMEM;
			__rb_link = &__rb_parent->rb_left;
		} else {
			rb_prev = __rb_parent;
			__rb_link = &__rb_parent->rb_right;
		}
	}

	*pprev = NULL;
	if (rb_prev)
		*pprev = rb_entry(rb_prev, struct vm_area_struct, vm_rb);
	*rb_link = __rb_link;
	*rb_parent = __rb_parent;
	return 0;
}

void __vma_link_rb(struct mm_struct *mm, struct vm_area_struct *vma,
		struct rb_node **rb_link, struct rb_node *rb_parent)
{
	/* Update tracking information for the gap following the new vma. */
	if (vma->vm_next)
		vma_gap_update(vma->vm_next);
	else
		mm->highest_vm_end = vma->vm_end;

	/*
	 * vma->vm_prev wasn't known when we followed the rbtree to find the
	 * correct insertion point for that vma. As a result, we could not
	 * update the vma vm_rb parents rb_subtree_gap values on the way down.
	 * So, we first insert the vma with a zero rb_subtree_gap value
	 * (to be consistent with what we did on the way down), and then
	 * immediately update the gap to the correct value. Finally we
	 * rebalance the rbtree after all augmented values have been set.
	 */
	rb_link_node(&vma->vm_rb, rb_parent, rb_link);
	vma->rb_subtree_gap = 0;
	vma_gap_update(vma);
	vma_rb_insert(vma, &mm->mm_rb);
}

static void __vma_link_file(struct vm_area_struct *vma)
{
	struct file *file;

	file = vma->vm_file;
	if (file) {
		struct address_space *mapping = file->f_mapping;

		if (vma->vm_flags & VM_DENYWRITE)
			atomic_dec(&file_inode(file)->i_writecount);
		if (vma->vm_flags & VM_SHARED)
			mapping->i_mmap_writable++;

		flush_dcache_mmap_lock(mapping);
		if (unlikely(vma->vm_flags & VM_NONLINEAR))
			vma_nonlinear_insert(vma, &mapping->i_mmap_nonlinear);
		else
			vma_interval_tree_insert(vma, &mapping->i_mmap);
		flush_dcache_mmap_unlock(mapping);
	}
}

static void
__vma_link(struct mm_struct *mm, struct vm_area_struct *vma,
	struct vm_area_struct *prev, struct rb_node **rb_link,
	struct rb_node *rb_parent)
{
	__vma_link_list(mm, vma, prev, rb_parent);
	__vma_link_rb(mm, vma, rb_link, rb_parent);
}

static void vma_link(struct mm_struct *mm, struct vm_area_struct *vma,
			struct vm_area_struct *prev, struct rb_node **rb_link,
			struct rb_node *rb_parent)
{
	struct address_space *mapping = NULL;

	if (vma->vm_file)
		mapping = vma->vm_file->f_mapping;

	if (mapping)
		mutex_lock(&mapping->i_mmap_mutex);

	__vma_link(mm, vma, prev, rb_link, rb_parent);
	__vma_link_file(vma);

	if (mapping)
		mutex_unlock(&mapping->i_mmap_mutex);

	mm->map_count++;
	validate_mm(mm);
}

/*
 * Helper for vma_adjust() in the split_vma insert case: insert a vma into the
 * mm's list and rbtree.  It has already been inserted into the interval tree.
 */
static void __insert_vm_struct(struct mm_struct *mm, struct vm_area_struct *vma)
{
	struct vm_area_struct *prev;
	struct rb_node **rb_link, *rb_parent;

	if (find_vma_links(mm, vma->vm_start, vma->vm_end,
			   &prev, &rb_link, &rb_parent))
		BUG();
	__vma_link(mm, vma, prev, rb_link, rb_parent);
	mm->map_count++;
}

static inline void
__vma_unlink(struct mm_struct *mm, struct vm_area_struct *vma,
		struct vm_area_struct *prev)
{
	struct vm_area_struct *next;

	vma_rb_erase(vma, &mm->mm_rb);
	prev->vm_next = next = vma->vm_next;
	if (next)
		next->vm_prev = prev;
	if (mm->mmap_cache == vma)
		mm->mmap_cache = prev;
}

/*
 * We cannot adjust vm_start, vm_end, vm_pgoff fields of a vma that
 * is already present in an i_mmap tree without adjusting the tree.
 * The following helper function should be used when such adjustments
 * are necessary.  The "insert" vma (if any) is to be inserted
 * before we drop the necessary locks.
 */
int vma_adjust(struct vm_area_struct *vma, unsigned long start,
	unsigned long end, pgoff_t pgoff, struct vm_area_struct *insert)
{
	struct mm_struct *mm = vma->vm_mm;
	struct vm_area_struct *next = vma->vm_next;
	struct vm_area_struct *importer = NULL;
	struct address_space *mapping = NULL;
	struct rb_root *root = NULL;
	struct anon_vma *anon_vma = NULL;
	struct file *file = vma->vm_file;
	bool start_changed = false, end_changed = false;
	long adjust_next = 0;
	int remove_next = 0;

	if (next && !insert) {
		struct vm_area_struct *exporter = NULL;

		if (end >= next->vm_end) {
			/*
			 * vma expands, overlapping all the next, and
			 * perhaps the one after too (mprotect case 6).
			 */
again:			remove_next = 1 + (end > next->vm_end);
			end = next->vm_end;
			exporter = next;
			importer = vma;
		} else if (end > next->vm_start) {
			/*
			 * vma expands, overlapping part of the next:
			 * mprotect case 5 shifting the boundary up.
			 */
			adjust_next = (end - next->vm_start) >> PAGE_SHIFT;
			exporter = next;
			importer = vma;
		} else if (end < vma->vm_end) {
			/*
			 * vma shrinks, and !insert tells it's not
			 * split_vma inserting another: so it must be
			 * mprotect case 4 shifting the boundary down.
			 */
			adjust_next = - ((vma->vm_end - end) >> PAGE_SHIFT);
			exporter = vma;
			importer = next;
		}

		/*
		 * Easily overlooked: when mprotect shifts the boundary,
		 * make sure the expanding vma has anon_vma set if the
		 * shrinking vma had, to cover any anon pages imported.
		 */
		if (exporter && exporter->anon_vma && !importer->anon_vma) {
			if (anon_vma_clone(importer, exporter))
				return -ENOMEM;
			importer->anon_vma = exporter->anon_vma;
		}
	}

	if (file) {
		mapping = file->f_mapping;
		if (!(vma->vm_flags & VM_NONLINEAR)) {
			root = &mapping->i_mmap;
			uprobe_munmap(vma, vma->vm_start, vma->vm_end);

			if (adjust_next)
				uprobe_munmap(next, next->vm_start,
							next->vm_end);
		}

		mutex_lock(&mapping->i_mmap_mutex);
		if (insert) {
			/*
			 * Put into interval tree now, so instantiated pages
			 * are visible to arm/parisc __flush_dcache_page
			 * throughout; but we cannot insert into address
			 * space until vma start or end is updated.
			 */
			__vma_link_file(insert);
		}
	}

	vma_adjust_trans_huge(vma, start, end, adjust_next);

	anon_vma = vma->anon_vma;
	if (!anon_vma && adjust_next)
		anon_vma = next->anon_vma;
	if (anon_vma) {
		VM_BUG_ON(adjust_next && next->anon_vma &&
			  anon_vma != next->anon_vma);
		anon_vma_lock_write(anon_vma);
		anon_vma_interval_tree_pre_update_vma(vma);
		if (adjust_next)
			anon_vma_interval_tree_pre_update_vma(next);
	}

	if (root) {
		flush_dcache_mmap_lock(mapping);
		vma_interval_tree_remove(vma, root);
		if (adjust_next)
			vma_interval_tree_remove(next, root);
	}

	if (start != vma->vm_start) {
		vma->vm_start = start;
		start_changed = true;
	}
	if (end != vma->vm_end) {


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