#include <linux/seq_file.h>
#include <linux/proc_fs.h>
#include <linux/migrate.h>
+#include <linux/ksm.h>
#include <linux/rmap.h>
#include <linux/security.h>
#include <linux/syscalls.h>
#include <linux/ctype.h>
+#include <linux/mm_inline.h>
#include <asm/tlbflush.h>
#include <asm/uaccess.h>
* Must be called holding task's alloc_lock to protect task's mems_allowed
* and mempolicy. May also be called holding the mmap_semaphore for write.
*/
-static int mpol_set_nodemask(struct mempolicy *pol, const nodemask_t *nodes)
+static int mpol_set_nodemask(struct mempolicy *pol,
+ const nodemask_t *nodes, struct nodemask_scratch *nsc)
{
- nodemask_t cpuset_context_nmask;
int ret;
/* if mode is MPOL_DEFAULT, pol is NULL. This is right. */
if (pol == NULL)
return 0;
+ /* Check N_HIGH_MEMORY */
+ nodes_and(nsc->mask1,
+ cpuset_current_mems_allowed, node_states[N_HIGH_MEMORY]);
VM_BUG_ON(!nodes);
if (pol->mode == MPOL_PREFERRED && nodes_empty(*nodes))
nodes = NULL; /* explicit local allocation */
else {
if (pol->flags & MPOL_F_RELATIVE_NODES)
- mpol_relative_nodemask(&cpuset_context_nmask, nodes,
- &cpuset_current_mems_allowed);
+ mpol_relative_nodemask(&nsc->mask2, nodes,&nsc->mask1);
else
- nodes_and(cpuset_context_nmask, *nodes,
- cpuset_current_mems_allowed);
+ nodes_and(nsc->mask2, *nodes, nsc->mask1);
+
if (mpol_store_user_nodemask(pol))
pol->w.user_nodemask = *nodes;
else
cpuset_current_mems_allowed;
}
- ret = mpol_ops[pol->mode].create(pol,
- nodes ? &cpuset_context_nmask : NULL);
+ if (nodes)
+ ret = mpol_ops[pol->mode].create(pol, &nsc->mask2);
+ else
+ ret = mpol_ops[pol->mode].create(pol, NULL);
return ret;
}
if (!page)
continue;
/*
- * The check for PageReserved here is important to avoid
- * handling zero pages and other pages that may have been
- * marked special by the system.
- *
- * If the PageReserved would not be checked here then f.e.
- * the location of the zero page could have an influence
- * on MPOL_MF_STRICT, zero pages would be counted for
- * the per node stats, and there would be useless attempts
- * to put zero pages on the migration list.
+ * vm_normal_page() filters out zero pages, but there might
+ * still be PageReserved pages to skip, perhaps in a VDSO.
+ * And we cannot move PageKsm pages sensibly or safely yet.
*/
- if (PageReserved(page))
+ if (PageReserved(page) || PageKsm(page))
continue;
nid = page_to_nid(page);
if (node_isset(nid, *nodes) == !!(flags & MPOL_MF_INVERT))
}
/* Step 2: apply policy to a range and do splits. */
-static int mbind_range(struct vm_area_struct *vma, unsigned long start,
- unsigned long end, struct mempolicy *new)
+static int mbind_range(struct mm_struct *mm, unsigned long start,
+ unsigned long end, struct mempolicy *new_pol)
{
struct vm_area_struct *next;
- int err;
+ struct vm_area_struct *prev;
+ struct vm_area_struct *vma;
+ int err = 0;
+ pgoff_t pgoff;
+ unsigned long vmstart;
+ unsigned long vmend;
- err = 0;
- for (; vma && vma->vm_start < end; vma = next) {
+ vma = find_vma_prev(mm, start, &prev);
+ if (!vma || vma->vm_start > start)
+ return -EFAULT;
+
+ for (; vma && vma->vm_start < end; prev = vma, vma = next) {
next = vma->vm_next;
- if (vma->vm_start < start)
- err = split_vma(vma->vm_mm, vma, start, 1);
- if (!err && vma->vm_end > end)
- err = split_vma(vma->vm_mm, vma, end, 0);
- if (!err)
- err = policy_vma(vma, new);
+ vmstart = max(start, vma->vm_start);
+ vmend = min(end, vma->vm_end);
+
+ pgoff = vma->vm_pgoff + ((start - vma->vm_start) >> PAGE_SHIFT);
+ prev = vma_merge(mm, prev, vmstart, vmend, vma->vm_flags,
+ vma->anon_vma, vma->vm_file, pgoff, new_pol);
+ if (prev) {
+ vma = prev;
+ next = vma->vm_next;
+ continue;
+ }
+ if (vma->vm_start != vmstart) {
+ err = split_vma(vma->vm_mm, vma, vmstart, 1);
+ if (err)
+ goto out;
+ }
+ if (vma->vm_end != vmend) {
+ err = split_vma(vma->vm_mm, vma, vmend, 0);
+ if (err)
+ goto out;
+ }
+ err = policy_vma(vma, new_pol);
if (err)
- break;
+ goto out;
}
+
+ out:
return err;
}
{
struct mempolicy *new, *old;
struct mm_struct *mm = current->mm;
+ NODEMASK_SCRATCH(scratch);
int ret;
- new = mpol_new(mode, flags, nodes);
- if (IS_ERR(new))
- return PTR_ERR(new);
+ if (!scratch)
+ return -ENOMEM;
+ new = mpol_new(mode, flags, nodes);
+ if (IS_ERR(new)) {
+ ret = PTR_ERR(new);
+ goto out;
+ }
/*
* prevent changing our mempolicy while show_numa_maps()
* is using it.
if (mm)
down_write(&mm->mmap_sem);
task_lock(current);
- ret = mpol_set_nodemask(new, nodes);
+ ret = mpol_set_nodemask(new, nodes, scratch);
if (ret) {
task_unlock(current);
if (mm)
up_write(&mm->mmap_sem);
mpol_put(new);
- return ret;
+ goto out;
}
old = current->mempolicy;
current->mempolicy = new;
up_write(&mm->mmap_sem);
mpol_put(old);
- return 0;
+ ret = 0;
+out:
+ NODEMASK_SCRATCH_FREE(scratch);
+ return ret;
}
/*
if ((flags & MPOL_MF_MOVE_ALL) || page_mapcount(page) == 1) {
if (!isolate_lru_page(page)) {
list_add_tail(&page->lru, pagelist);
+ inc_zone_page_state(page, NR_ISOLATED_ANON +
+ page_is_file_cache(page));
}
}
}
static struct page *new_node_page(struct page *page, unsigned long node, int **x)
{
- return alloc_pages_node(node, GFP_HIGHUSER_MOVABLE, 0);
+ return alloc_pages_exact_node(node, GFP_HIGHUSER_MOVABLE, 0);
}
/*
flags | MPOL_MF_DISCONTIG_OK, &pagelist);
if (!list_empty(&pagelist))
- err = migrate_pages(&pagelist, new_node_page, dest);
+ err = migrate_pages(&pagelist, new_node_page, dest, 0);
return err;
}
if (err)
goto out;
-/*
- * Find a 'source' bit set in 'tmp' whose corresponding 'dest'
- * bit in 'to' is not also set in 'tmp'. Clear the found 'source'
- * bit in 'tmp', and return that <source, dest> pair for migration.
- * The pair of nodemasks 'to' and 'from' define the map.
- *
- * If no pair of bits is found that way, fallback to picking some
- * pair of 'source' and 'dest' bits that are not the same. If the
- * 'source' and 'dest' bits are the same, this represents a node
- * that will be migrating to itself, so no pages need move.
- *
- * If no bits are left in 'tmp', or if all remaining bits left
- * in 'tmp' correspond to the same bit in 'to', return false
- * (nothing left to migrate).
- *
- * This lets us pick a pair of nodes to migrate between, such that
- * if possible the dest node is not already occupied by some other
- * source node, minimizing the risk of overloading the memory on a
- * node that would happen if we migrated incoming memory to a node
- * before migrating outgoing memory source that same node.
- *
- * A single scan of tmp is sufficient. As we go, we remember the
- * most recent <s, d> pair that moved (s != d). If we find a pair
- * that not only moved, but what's better, moved to an empty slot
- * (d is not set in tmp), then we break out then, with that pair.
- * Otherwise when we finish scannng from_tmp, we at least have the
- * most recent <s, d> pair that moved. If we get all the way through
- * the scan of tmp without finding any node that moved, much less
- * moved to an empty node, then there is nothing left worth migrating.
- */
+ /*
+ * Find a 'source' bit set in 'tmp' whose corresponding 'dest'
+ * bit in 'to' is not also set in 'tmp'. Clear the found 'source'
+ * bit in 'tmp', and return that <source, dest> pair for migration.
+ * The pair of nodemasks 'to' and 'from' define the map.
+ *
+ * If no pair of bits is found that way, fallback to picking some
+ * pair of 'source' and 'dest' bits that are not the same. If the
+ * 'source' and 'dest' bits are the same, this represents a node
+ * that will be migrating to itself, so no pages need move.
+ *
+ * If no bits are left in 'tmp', or if all remaining bits left
+ * in 'tmp' correspond to the same bit in 'to', return false
+ * (nothing left to migrate).
+ *
+ * This lets us pick a pair of nodes to migrate between, such that
+ * if possible the dest node is not already occupied by some other
+ * source node, minimizing the risk of overloading the memory on a
+ * node that would happen if we migrated incoming memory to a node
+ * before migrating outgoing memory source that same node.
+ *
+ * A single scan of tmp is sufficient. As we go, we remember the
+ * most recent <s, d> pair that moved (s != d). If we find a pair
+ * that not only moved, but what's better, moved to an empty slot
+ * (d is not set in tmp), then we break out then, with that pair.
+ * Otherwise when we finish scannng from_tmp, we at least have the
+ * most recent <s, d> pair that moved. If we get all the way through
+ * the scan of tmp without finding any node that moved, much less
+ * moved to an empty node, then there is nothing left worth migrating.
+ */
tmp = *from_nodes;
while (!nodes_empty(tmp)) {
err = migrate_prep();
if (err)
- return err;
+ goto mpol_out;
}
- down_write(&mm->mmap_sem);
- task_lock(current);
- err = mpol_set_nodemask(new, nmask);
- task_unlock(current);
- if (err) {
- up_write(&mm->mmap_sem);
- mpol_put(new);
- return err;
+ {
+ NODEMASK_SCRATCH(scratch);
+ if (scratch) {
+ down_write(&mm->mmap_sem);
+ task_lock(current);
+ err = mpol_set_nodemask(new, nmask, scratch);
+ task_unlock(current);
+ if (err)
+ up_write(&mm->mmap_sem);
+ } else
+ err = -ENOMEM;
+ NODEMASK_SCRATCH_FREE(scratch);
}
+ if (err)
+ goto mpol_out;
+
vma = check_range(mm, start, end, nmask,
flags | MPOL_MF_INVERT, &pagelist);
if (!IS_ERR(vma)) {
int nr_failed = 0;
- err = mbind_range(vma, start, end, new);
+ err = mbind_range(mm, start, end, new);
if (!list_empty(&pagelist))
nr_failed = migrate_pages(&pagelist, new_vma_page,
- (unsigned long)vma);
+ (unsigned long)vma, 0);
if (!err && nr_failed && (flags & MPOL_MF_STRICT))
err = -EIO;
- }
+ } else
+ putback_lru_pages(&pagelist);
up_write(&mm->mmap_sem);
+ mpol_out:
mpol_put(new);
return err;
}
}
return zl;
}
+
+/*
+ * init_nodemask_of_mempolicy
+ *
+ * If the current task's mempolicy is "default" [NULL], return 'false'
+ * to indicate default policy. Otherwise, extract the policy nodemask
+ * for 'bind' or 'interleave' policy into the argument nodemask, or
+ * initialize the argument nodemask to contain the single node for
+ * 'preferred' or 'local' policy and return 'true' to indicate presence
+ * of non-default mempolicy.
+ *
+ * We don't bother with reference counting the mempolicy [mpol_get/put]
+ * because the current task is examining it's own mempolicy and a task's
+ * mempolicy is only ever changed by the task itself.
+ *
+ * N.B., it is the caller's responsibility to free a returned nodemask.
+ */
+bool init_nodemask_of_mempolicy(nodemask_t *mask)
+{
+ struct mempolicy *mempolicy;
+ int nid;
+
+ if (!(mask && current->mempolicy))
+ return false;
+
+ mempolicy = current->mempolicy;
+ switch (mempolicy->mode) {
+ case MPOL_PREFERRED:
+ if (mempolicy->flags & MPOL_F_LOCAL)
+ nid = numa_node_id();
+ else
+ nid = mempolicy->v.preferred_node;
+ init_nodemask_of_node(mask, nid);
+ break;
+
+ case MPOL_BIND:
+ /* Fall through */
+ case MPOL_INTERLEAVE:
+ *mask = mempolicy->v.nodes;
+ break;
+
+ default:
+ BUG();
+ }
+
+ return true;
+}
#endif
/* Allocate a page in interleaved policy.
if (!new)
return ERR_PTR(-ENOMEM);
+ rcu_read_lock();
if (current_cpuset_is_being_rebound()) {
nodemask_t mems = cpuset_mems_allowed(current);
mpol_rebind_policy(old, &mems);
}
+ rcu_read_unlock();
*new = *old;
atomic_set(&new->refcnt, 1);
return new;
* Install non-NULL @mpol in inode's shared policy rb-tree.
* On entry, the current task has a reference on a non-NULL @mpol.
* This must be released on exit.
+ * This is called at get_inode() calls and we can use GFP_KERNEL.
*/
void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol)
{
if (mpol) {
struct vm_area_struct pvma;
struct mempolicy *new;
+ NODEMASK_SCRATCH(scratch);
+ if (!scratch)
+ return;
/* contextualize the tmpfs mount point mempolicy */
new = mpol_new(mpol->mode, mpol->flags, &mpol->w.user_nodemask);
if (IS_ERR(new)) {
mpol_put(mpol); /* drop our ref on sb mpol */
+ NODEMASK_SCRATCH_FREE(scratch);
return; /* no valid nodemask intersection */
}
task_lock(current);
- ret = mpol_set_nodemask(new, &mpol->w.user_nodemask);
+ ret = mpol_set_nodemask(new, &mpol->w.user_nodemask, scratch);
task_unlock(current);
mpol_put(mpol); /* drop our ref on sb mpol */
if (ret) {
+ NODEMASK_SCRATCH_FREE(scratch);
mpol_put(new);
return;
}
pvma.vm_end = TASK_SIZE; /* policy covers entire file */
mpol_set_shared_policy(sp, &pvma, new); /* adds ref */
mpol_put(new); /* drop initial ref */
+ NODEMASK_SCRATCH_FREE(scratch);
}
}
err = 1;
else {
int ret;
-
- task_lock(current);
- ret = mpol_set_nodemask(new, &nodes);
- task_unlock(current);
- if (ret)
+ NODEMASK_SCRATCH(scratch);
+ if (scratch) {
+ task_lock(current);
+ ret = mpol_set_nodemask(new, &nodes, scratch);
+ task_unlock(current);
+ } else
+ ret = -ENOMEM;
+ NODEMASK_SCRATCH_FREE(scratch);
+ if (ret) {
err = 1;
- else if (no_context) {
+ mpol_put(new);
+ } else if (no_context) {
/* save for contextualization */
new->w.user_nodemask = nodes;
}