| // SPDX-License-Identifier: GPL-2.0-only |
| /* |
| * Simple NUMA memory policy for the Linux kernel. |
| * |
| * Copyright 2003,2004 Andi Kleen, SuSE Labs. |
| * (C) Copyright 2005 Christoph Lameter, Silicon Graphics, Inc. |
| * |
| * NUMA policy allows the user to give hints in which node(s) memory should |
| * be allocated. |
| * |
| * Support four policies per VMA and per process: |
| * |
| * The VMA policy has priority over the process policy for a page fault. |
| * |
| * interleave Allocate memory interleaved over a set of nodes, |
| * with normal fallback if it fails. |
| * For VMA based allocations this interleaves based on the |
| * offset into the backing object or offset into the mapping |
| * for anonymous memory. For process policy an process counter |
| * is used. |
| * |
| * weighted interleave |
| * Allocate memory interleaved over a set of nodes based on |
| * a set of weights (per-node), with normal fallback if it |
| * fails. Otherwise operates the same as interleave. |
| * Example: nodeset(0,1) & weights (2,1) - 2 pages allocated |
| * on node 0 for every 1 page allocated on node 1. |
| * |
| * bind Only allocate memory on a specific set of nodes, |
| * no fallback. |
| * FIXME: memory is allocated starting with the first node |
| * to the last. It would be better if bind would truly restrict |
| * the allocation to memory nodes instead |
| * |
| * preferred Try a specific node first before normal fallback. |
| * As a special case NUMA_NO_NODE here means do the allocation |
| * on the local CPU. This is normally identical to default, |
| * but useful to set in a VMA when you have a non default |
| * process policy. |
| * |
| * preferred many Try a set of nodes first before normal fallback. This is |
| * similar to preferred without the special case. |
| * |
| * default Allocate on the local node first, or when on a VMA |
| * use the process policy. This is what Linux always did |
| * in a NUMA aware kernel and still does by, ahem, default. |
| * |
| * The process policy is applied for most non interrupt memory allocations |
| * in that process' context. Interrupts ignore the policies and always |
| * try to allocate on the local CPU. The VMA policy is only applied for memory |
| * allocations for a VMA in the VM. |
| * |
| * Currently there are a few corner cases in swapping where the policy |
| * is not applied, but the majority should be handled. When process policy |
| * is used it is not remembered over swap outs/swap ins. |
| * |
| * Only the highest zone in the zone hierarchy gets policied. Allocations |
| * requesting a lower zone just use default policy. This implies that |
| * on systems with highmem kernel lowmem allocation don't get policied. |
| * Same with GFP_DMA allocations. |
| * |
| * For shmem/tmpfs shared memory the policy is shared between |
| * all users and remembered even when nobody has memory mapped. |
| */ |
| |
| /* Notebook: |
| fix mmap readahead to honour policy and enable policy for any page cache |
| object |
| statistics for bigpages |
| global policy for page cache? currently it uses process policy. Requires |
| first item above. |
| handle mremap for shared memory (currently ignored for the policy) |
| grows down? |
| make bind policy root only? It can trigger oom much faster and the |
| kernel is not always grateful with that. |
| */ |
| |
| #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
| |
| #include <linux/mempolicy.h> |
| #include <linux/pagewalk.h> |
| #include <linux/highmem.h> |
| #include <linux/hugetlb.h> |
| #include <linux/kernel.h> |
| #include <linux/sched.h> |
| #include <linux/sched/mm.h> |
| #include <linux/sched/numa_balancing.h> |
| #include <linux/sched/task.h> |
| #include <linux/nodemask.h> |
| #include <linux/cpuset.h> |
| #include <linux/slab.h> |
| #include <linux/string.h> |
| #include <linux/export.h> |
| #include <linux/nsproxy.h> |
| #include <linux/interrupt.h> |
| #include <linux/init.h> |
| #include <linux/compat.h> |
| #include <linux/ptrace.h> |
| #include <linux/swap.h> |
| #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 <linux/mmu_notifier.h> |
| #include <linux/printk.h> |
| #include <linux/swapops.h> |
| |
| #include <asm/tlbflush.h> |
| #include <asm/tlb.h> |
| #include <linux/uaccess.h> |
| |
| #include "internal.h" |
| |
| /* Internal flags */ |
| #define MPOL_MF_DISCONTIG_OK (MPOL_MF_INTERNAL << 0) /* Skip checks for continuous vmas */ |
| #define MPOL_MF_INVERT (MPOL_MF_INTERNAL << 1) /* Invert check for nodemask */ |
| #define MPOL_MF_WRLOCK (MPOL_MF_INTERNAL << 2) /* Write-lock walked vmas */ |
| |
| static struct kmem_cache *policy_cache; |
| static struct kmem_cache *sn_cache; |
| |
| /* Highest zone. An specific allocation for a zone below that is not |
| policied. */ |
| enum zone_type policy_zone = 0; |
| |
| /* |
| * run-time system-wide default policy => local allocation |
| */ |
| static struct mempolicy default_policy = { |
| .refcnt = ATOMIC_INIT(1), /* never free it */ |
| .mode = MPOL_LOCAL, |
| }; |
| |
| static struct mempolicy preferred_node_policy[MAX_NUMNODES]; |
| |
| /* |
| * iw_table is the sysfs-set interleave weight table, a value of 0 denotes |
| * system-default value should be used. A NULL iw_table also denotes that |
| * system-default values should be used. Until the system-default table |
| * is implemented, the system-default is always 1. |
| * |
| * iw_table is RCU protected |
| */ |
| static u8 __rcu *iw_table; |
| static DEFINE_MUTEX(iw_table_lock); |
| |
| static u8 get_il_weight(int node) |
| { |
| u8 *table; |
| u8 weight; |
| |
| rcu_read_lock(); |
| table = rcu_dereference(iw_table); |
| /* if no iw_table, use system default */ |
| weight = table ? table[node] : 1; |
| /* if value in iw_table is 0, use system default */ |
| weight = weight ? weight : 1; |
| rcu_read_unlock(); |
| return weight; |
| } |
| |
| /** |
| * numa_nearest_node - Find nearest node by state |
| * @node: Node id to start the search |
| * @state: State to filter the search |
| * |
| * Lookup the closest node by distance if @nid is not in state. |
| * |
| * Return: this @node if it is in state, otherwise the closest node by distance |
| */ |
| int numa_nearest_node(int node, unsigned int state) |
| { |
| int min_dist = INT_MAX, dist, n, min_node; |
| |
| if (state >= NR_NODE_STATES) |
| return -EINVAL; |
| |
| if (node == NUMA_NO_NODE || node_state(node, state)) |
| return node; |
| |
| min_node = node; |
| for_each_node_state(n, state) { |
| dist = node_distance(node, n); |
| if (dist < min_dist) { |
| min_dist = dist; |
| min_node = n; |
| } |
| } |
| |
| return min_node; |
| } |
| EXPORT_SYMBOL_GPL(numa_nearest_node); |
| |
| struct mempolicy *get_task_policy(struct task_struct *p) |
| { |
| struct mempolicy *pol = p->mempolicy; |
| int node; |
| |
| if (pol) |
| return pol; |
| |
| node = numa_node_id(); |
| if (node != NUMA_NO_NODE) { |
| pol = &preferred_node_policy[node]; |
| /* preferred_node_policy is not initialised early in boot */ |
| if (pol->mode) |
| return pol; |
| } |
| |
| return &default_policy; |
| } |
| |
| static const struct mempolicy_operations { |
| int (*create)(struct mempolicy *pol, const nodemask_t *nodes); |
| void (*rebind)(struct mempolicy *pol, const nodemask_t *nodes); |
| } mpol_ops[MPOL_MAX]; |
| |
| static inline int mpol_store_user_nodemask(const struct mempolicy *pol) |
| { |
| return pol->flags & MPOL_MODE_FLAGS; |
| } |
| |
| static void mpol_relative_nodemask(nodemask_t *ret, const nodemask_t *orig, |
| const nodemask_t *rel) |
| { |
| nodemask_t tmp; |
| nodes_fold(tmp, *orig, nodes_weight(*rel)); |
| nodes_onto(*ret, tmp, *rel); |
| } |
| |
| static int mpol_new_nodemask(struct mempolicy *pol, const nodemask_t *nodes) |
| { |
| if (nodes_empty(*nodes)) |
| return -EINVAL; |
| pol->nodes = *nodes; |
| return 0; |
| } |
| |
| static int mpol_new_preferred(struct mempolicy *pol, const nodemask_t *nodes) |
| { |
| if (nodes_empty(*nodes)) |
| return -EINVAL; |
| |
| nodes_clear(pol->nodes); |
| node_set(first_node(*nodes), pol->nodes); |
| return 0; |
| } |
| |
| /* |
| * mpol_set_nodemask is called after mpol_new() to set up the nodemask, if |
| * any, for the new policy. mpol_new() has already validated the nodes |
| * parameter with respect to the policy mode and flags. |
| * |
| * Must be called holding task's alloc_lock to protect task's mems_allowed |
| * and mempolicy. May also be called holding the mmap_lock for write. |
| */ |
| static int mpol_set_nodemask(struct mempolicy *pol, |
| const nodemask_t *nodes, struct nodemask_scratch *nsc) |
| { |
| int ret; |
| |
| /* |
| * Default (pol==NULL) resp. local memory policies are not a |
| * subject of any remapping. They also do not need any special |
| * constructor. |
| */ |
| if (!pol || pol->mode == MPOL_LOCAL) |
| return 0; |
| |
| /* Check N_MEMORY */ |
| nodes_and(nsc->mask1, |
| cpuset_current_mems_allowed, node_states[N_MEMORY]); |
| |
| VM_BUG_ON(!nodes); |
| |
| if (pol->flags & MPOL_F_RELATIVE_NODES) |
| mpol_relative_nodemask(&nsc->mask2, nodes, &nsc->mask1); |
| else |
| nodes_and(nsc->mask2, *nodes, nsc->mask1); |
| |
| if (mpol_store_user_nodemask(pol)) |
| pol->w.user_nodemask = *nodes; |
| else |
| pol->w.cpuset_mems_allowed = cpuset_current_mems_allowed; |
| |
| ret = mpol_ops[pol->mode].create(pol, &nsc->mask2); |
| return ret; |
| } |
| |
| /* |
| * This function just creates a new policy, does some check and simple |
| * initialization. You must invoke mpol_set_nodemask() to set nodes. |
| */ |
| static struct mempolicy *mpol_new(unsigned short mode, unsigned short flags, |
| nodemask_t *nodes) |
| { |
| struct mempolicy *policy; |
| |
| if (mode == MPOL_DEFAULT) { |
| if (nodes && !nodes_empty(*nodes)) |
| return ERR_PTR(-EINVAL); |
| return NULL; |
| } |
| VM_BUG_ON(!nodes); |
| |
| /* |
| * MPOL_PREFERRED cannot be used with MPOL_F_STATIC_NODES or |
| * MPOL_F_RELATIVE_NODES if the nodemask is empty (local allocation). |
| * All other modes require a valid pointer to a non-empty nodemask. |
| */ |
| if (mode == MPOL_PREFERRED) { |
| if (nodes_empty(*nodes)) { |
| if (((flags & MPOL_F_STATIC_NODES) || |
| (flags & MPOL_F_RELATIVE_NODES))) |
| return ERR_PTR(-EINVAL); |
| |
| mode = MPOL_LOCAL; |
| } |
| } else if (mode == MPOL_LOCAL) { |
| if (!nodes_empty(*nodes) || |
| (flags & MPOL_F_STATIC_NODES) || |
| (flags & MPOL_F_RELATIVE_NODES)) |
| return ERR_PTR(-EINVAL); |
| } else if (nodes_empty(*nodes)) |
| return ERR_PTR(-EINVAL); |
| |
| policy = kmem_cache_alloc(policy_cache, GFP_KERNEL); |
| if (!policy) |
| return ERR_PTR(-ENOMEM); |
| atomic_set(&policy->refcnt, 1); |
| policy->mode = mode; |
| policy->flags = flags; |
| policy->home_node = NUMA_NO_NODE; |
| |
| return policy; |
| } |
| |
| /* Slow path of a mpol destructor. */ |
| void __mpol_put(struct mempolicy *pol) |
| { |
| if (!atomic_dec_and_test(&pol->refcnt)) |
| return; |
| kmem_cache_free(policy_cache, pol); |
| } |
| |
| static void mpol_rebind_default(struct mempolicy *pol, const nodemask_t *nodes) |
| { |
| } |
| |
| static void mpol_rebind_nodemask(struct mempolicy *pol, const nodemask_t *nodes) |
| { |
| nodemask_t tmp; |
| |
| if (pol->flags & MPOL_F_STATIC_NODES) |
| nodes_and(tmp, pol->w.user_nodemask, *nodes); |
| else if (pol->flags & MPOL_F_RELATIVE_NODES) |
| mpol_relative_nodemask(&tmp, &pol->w.user_nodemask, nodes); |
| else { |
| nodes_remap(tmp, pol->nodes, pol->w.cpuset_mems_allowed, |
| *nodes); |
| pol->w.cpuset_mems_allowed = *nodes; |
| } |
| |
| if (nodes_empty(tmp)) |
| tmp = *nodes; |
| |
| pol->nodes = tmp; |
| } |
| |
| static void mpol_rebind_preferred(struct mempolicy *pol, |
| const nodemask_t *nodes) |
| { |
| pol->w.cpuset_mems_allowed = *nodes; |
| } |
| |
| /* |
| * mpol_rebind_policy - Migrate a policy to a different set of nodes |
| * |
| * Per-vma policies are protected by mmap_lock. Allocations using per-task |
| * policies are protected by task->mems_allowed_seq to prevent a premature |
| * OOM/allocation failure due to parallel nodemask modification. |
| */ |
| static void mpol_rebind_policy(struct mempolicy *pol, const nodemask_t *newmask) |
| { |
| if (!pol || pol->mode == MPOL_LOCAL) |
| return; |
| if (!mpol_store_user_nodemask(pol) && |
| nodes_equal(pol->w.cpuset_mems_allowed, *newmask)) |
| return; |
| |
| mpol_ops[pol->mode].rebind(pol, newmask); |
| } |
| |
| /* |
| * Wrapper for mpol_rebind_policy() that just requires task |
| * pointer, and updates task mempolicy. |
| * |
| * Called with task's alloc_lock held. |
| */ |
| void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new) |
| { |
| mpol_rebind_policy(tsk->mempolicy, new); |
| } |
| |
| /* |
| * Rebind each vma in mm to new nodemask. |
| * |
| * Call holding a reference to mm. Takes mm->mmap_lock during call. |
| */ |
| void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new) |
| { |
| struct vm_area_struct *vma; |
| VMA_ITERATOR(vmi, mm, 0); |
| |
| mmap_write_lock(mm); |
| for_each_vma(vmi, vma) { |
| vma_start_write(vma); |
| mpol_rebind_policy(vma->vm_policy, new); |
| } |
| mmap_write_unlock(mm); |
| } |
| |
| static const struct mempolicy_operations mpol_ops[MPOL_MAX] = { |
| [MPOL_DEFAULT] = { |
| .rebind = mpol_rebind_default, |
| }, |
| [MPOL_INTERLEAVE] = { |
| .create = mpol_new_nodemask, |
| .rebind = mpol_rebind_nodemask, |
| }, |
| [MPOL_PREFERRED] = { |
| .create = mpol_new_preferred, |
| .rebind = mpol_rebind_preferred, |
| }, |
| [MPOL_BIND] = { |
| .create = mpol_new_nodemask, |
| .rebind = mpol_rebind_nodemask, |
| }, |
| [MPOL_LOCAL] = { |
| .rebind = mpol_rebind_default, |
| }, |
| [MPOL_PREFERRED_MANY] = { |
| .create = mpol_new_nodemask, |
| .rebind = mpol_rebind_preferred, |
| }, |
| [MPOL_WEIGHTED_INTERLEAVE] = { |
| .create = mpol_new_nodemask, |
| .rebind = mpol_rebind_nodemask, |
| }, |
| }; |
| |
| static bool migrate_folio_add(struct folio *folio, struct list_head *foliolist, |
| unsigned long flags); |
| static nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *pol, |
| pgoff_t ilx, int *nid); |
| |
| static bool strictly_unmovable(unsigned long flags) |
| { |
| /* |
| * STRICT without MOVE flags lets do_mbind() fail immediately with -EIO |
| * if any misplaced page is found. |
| */ |
| return (flags & (MPOL_MF_STRICT | MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) == |
| MPOL_MF_STRICT; |
| } |
| |
| struct migration_mpol { /* for alloc_migration_target_by_mpol() */ |
| struct mempolicy *pol; |
| pgoff_t ilx; |
| }; |
| |
| struct queue_pages { |
| struct list_head *pagelist; |
| unsigned long flags; |
| nodemask_t *nmask; |
| unsigned long start; |
| unsigned long end; |
| struct vm_area_struct *first; |
| struct folio *large; /* note last large folio encountered */ |
| long nr_failed; /* could not be isolated at this time */ |
| }; |
| |
| /* |
| * Check if the folio's nid is in qp->nmask. |
| * |
| * If MPOL_MF_INVERT is set in qp->flags, check if the nid is |
| * in the invert of qp->nmask. |
| */ |
| static inline bool queue_folio_required(struct folio *folio, |
| struct queue_pages *qp) |
| { |
| int nid = folio_nid(folio); |
| unsigned long flags = qp->flags; |
| |
| return node_isset(nid, *qp->nmask) == !(flags & MPOL_MF_INVERT); |
| } |
| |
| static void queue_folios_pmd(pmd_t *pmd, struct mm_walk *walk) |
| { |
| struct folio *folio; |
| struct queue_pages *qp = walk->private; |
| |
| if (unlikely(is_pmd_migration_entry(*pmd))) { |
| qp->nr_failed++; |
| return; |
| } |
| folio = pfn_folio(pmd_pfn(*pmd)); |
| if (is_huge_zero_page(&folio->page)) { |
| walk->action = ACTION_CONTINUE; |
| return; |
| } |
| if (!queue_folio_required(folio, qp)) |
| return; |
| if (!(qp->flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) || |
| !vma_migratable(walk->vma) || |
| !migrate_folio_add(folio, qp->pagelist, qp->flags)) |
| qp->nr_failed++; |
| } |
| |
| /* |
| * Scan through folios, checking if they satisfy the required conditions, |
| * moving them from LRU to local pagelist for migration if they do (or not). |
| * |
| * queue_folios_pte_range() has two possible return values: |
| * 0 - continue walking to scan for more, even if an existing folio on the |
| * wrong node could not be isolated and queued for migration. |
| * -EIO - only MPOL_MF_STRICT was specified, without MPOL_MF_MOVE or ..._ALL, |
| * and an existing folio was on a node that does not follow the policy. |
| */ |
| static int queue_folios_pte_range(pmd_t *pmd, unsigned long addr, |
| unsigned long end, struct mm_walk *walk) |
| { |
| struct vm_area_struct *vma = walk->vma; |
| struct folio *folio; |
| struct queue_pages *qp = walk->private; |
| unsigned long flags = qp->flags; |
| pte_t *pte, *mapped_pte; |
| pte_t ptent; |
| spinlock_t *ptl; |
| |
| ptl = pmd_trans_huge_lock(pmd, vma); |
| if (ptl) { |
| queue_folios_pmd(pmd, walk); |
| spin_unlock(ptl); |
| goto out; |
| } |
| |
| mapped_pte = pte = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); |
| if (!pte) { |
| walk->action = ACTION_AGAIN; |
| return 0; |
| } |
| for (; addr != end; pte++, addr += PAGE_SIZE) { |
| ptent = ptep_get(pte); |
| if (pte_none(ptent)) |
| continue; |
| if (!pte_present(ptent)) { |
| if (is_migration_entry(pte_to_swp_entry(ptent))) |
| qp->nr_failed++; |
| continue; |
| } |
| folio = vm_normal_folio(vma, addr, ptent); |
| if (!folio || folio_is_zone_device(folio)) |
| continue; |
| /* |
| * vm_normal_folio() filters out zero pages, but there might |
| * still be reserved folios to skip, perhaps in a VDSO. |
| */ |
| if (folio_test_reserved(folio)) |
| continue; |
| if (!queue_folio_required(folio, qp)) |
| continue; |
| if (folio_test_large(folio)) { |
| /* |
| * A large folio can only be isolated from LRU once, |
| * but may be mapped by many PTEs (and Copy-On-Write may |
| * intersperse PTEs of other, order 0, folios). This is |
| * a common case, so don't mistake it for failure (but |
| * there can be other cases of multi-mapped pages which |
| * this quick check does not help to filter out - and a |
| * search of the pagelist might grow to be prohibitive). |
| * |
| * migrate_pages(&pagelist) returns nr_failed folios, so |
| * check "large" now so that queue_pages_range() returns |
| * a comparable nr_failed folios. This does imply that |
| * if folio could not be isolated for some racy reason |
| * at its first PTE, later PTEs will not give it another |
| * chance of isolation; but keeps the accounting simple. |
| */ |
| if (folio == qp->large) |
| continue; |
| qp->large = folio; |
| } |
| if (!(flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) || |
| !vma_migratable(vma) || |
| !migrate_folio_add(folio, qp->pagelist, flags)) { |
| qp->nr_failed++; |
| if (strictly_unmovable(flags)) |
| break; |
| } |
| } |
| pte_unmap_unlock(mapped_pte, ptl); |
| cond_resched(); |
| out: |
| if (qp->nr_failed && strictly_unmovable(flags)) |
| return -EIO; |
| return 0; |
| } |
| |
| static int queue_folios_hugetlb(pte_t *pte, unsigned long hmask, |
| unsigned long addr, unsigned long end, |
| struct mm_walk *walk) |
| { |
| #ifdef CONFIG_HUGETLB_PAGE |
| struct queue_pages *qp = walk->private; |
| unsigned long flags = qp->flags; |
| struct folio *folio; |
| spinlock_t *ptl; |
| pte_t entry; |
| |
| ptl = huge_pte_lock(hstate_vma(walk->vma), walk->mm, pte); |
| entry = huge_ptep_get(pte); |
| if (!pte_present(entry)) { |
| if (unlikely(is_hugetlb_entry_migration(entry))) |
| qp->nr_failed++; |
| goto unlock; |
| } |
| folio = pfn_folio(pte_pfn(entry)); |
| if (!queue_folio_required(folio, qp)) |
| goto unlock; |
| if (!(flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) || |
| !vma_migratable(walk->vma)) { |
| qp->nr_failed++; |
| goto unlock; |
| } |
| /* |
| * Unless MPOL_MF_MOVE_ALL, we try to avoid migrating a shared folio. |
| * Choosing not to migrate a shared folio is not counted as a failure. |
| * |
| * To check if the folio is shared, ideally we want to make sure |
| * every page is mapped to the same process. Doing that is very |
| * expensive, so check the estimated sharers of the folio instead. |
| */ |
| if ((flags & MPOL_MF_MOVE_ALL) || |
| (folio_estimated_sharers(folio) == 1 && !hugetlb_pmd_shared(pte))) |
| if (!isolate_hugetlb(folio, qp->pagelist)) |
| qp->nr_failed++; |
| unlock: |
| spin_unlock(ptl); |
| if (qp->nr_failed && strictly_unmovable(flags)) |
| return -EIO; |
| #endif |
| return 0; |
| } |
| |
| #ifdef CONFIG_NUMA_BALANCING |
| /* |
| * This is used to mark a range of virtual addresses to be inaccessible. |
| * These are later cleared by a NUMA hinting fault. Depending on these |
| * faults, pages may be migrated for better NUMA placement. |
| * |
| * This is assuming that NUMA faults are handled using PROT_NONE. If |
| * an architecture makes a different choice, it will need further |
| * changes to the core. |
| */ |
| unsigned long change_prot_numa(struct vm_area_struct *vma, |
| unsigned long addr, unsigned long end) |
| { |
| struct mmu_gather tlb; |
| long nr_updated; |
| |
| tlb_gather_mmu(&tlb, vma->vm_mm); |
| |
| nr_updated = change_protection(&tlb, vma, addr, end, MM_CP_PROT_NUMA); |
| if (nr_updated > 0) |
| count_vm_numa_events(NUMA_PTE_UPDATES, nr_updated); |
| |
| tlb_finish_mmu(&tlb); |
| |
| return nr_updated; |
| } |
| #endif /* CONFIG_NUMA_BALANCING */ |
| |
| static int queue_pages_test_walk(unsigned long start, unsigned long end, |
| struct mm_walk *walk) |
| { |
| struct vm_area_struct *next, *vma = walk->vma; |
| struct queue_pages *qp = walk->private; |
| unsigned long flags = qp->flags; |
| |
| /* range check first */ |
| VM_BUG_ON_VMA(!range_in_vma(vma, start, end), vma); |
| |
| if (!qp->first) { |
| qp->first = vma; |
| if (!(flags & MPOL_MF_DISCONTIG_OK) && |
| (qp->start < vma->vm_start)) |
| /* hole at head side of range */ |
| return -EFAULT; |
| } |
| next = find_vma(vma->vm_mm, vma->vm_end); |
| if (!(flags & MPOL_MF_DISCONTIG_OK) && |
| ((vma->vm_end < qp->end) && |
| (!next || vma->vm_end < next->vm_start))) |
| /* hole at middle or tail of range */ |
| return -EFAULT; |
| |
| /* |
| * Need check MPOL_MF_STRICT to return -EIO if possible |
| * regardless of vma_migratable |
| */ |
| if (!vma_migratable(vma) && |
| !(flags & MPOL_MF_STRICT)) |
| return 1; |
| |
| /* |
| * Check page nodes, and queue pages to move, in the current vma. |
| * But if no moving, and no strict checking, the scan can be skipped. |
| */ |
| if (flags & (MPOL_MF_STRICT | MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) |
| return 0; |
| return 1; |
| } |
| |
| static const struct mm_walk_ops queue_pages_walk_ops = { |
| .hugetlb_entry = queue_folios_hugetlb, |
| .pmd_entry = queue_folios_pte_range, |
| .test_walk = queue_pages_test_walk, |
| .walk_lock = PGWALK_RDLOCK, |
| }; |
| |
| static const struct mm_walk_ops queue_pages_lock_vma_walk_ops = { |
| .hugetlb_entry = queue_folios_hugetlb, |
| .pmd_entry = queue_folios_pte_range, |
| .test_walk = queue_pages_test_walk, |
| .walk_lock = PGWALK_WRLOCK, |
| }; |
| |
| /* |
| * Walk through page tables and collect pages to be migrated. |
| * |
| * If pages found in a given range are not on the required set of @nodes, |
| * and migration is allowed, they are isolated and queued to @pagelist. |
| * |
| * queue_pages_range() may return: |
| * 0 - all pages already on the right node, or successfully queued for moving |
| * (or neither strict checking nor moving requested: only range checking). |
| * >0 - this number of misplaced folios could not be queued for moving |
| * (a hugetlbfs page or a transparent huge page being counted as 1). |
| * -EIO - a misplaced page found, when MPOL_MF_STRICT specified without MOVEs. |
| * -EFAULT - a hole in the memory range, when MPOL_MF_DISCONTIG_OK unspecified. |
| */ |
| static long |
| queue_pages_range(struct mm_struct *mm, unsigned long start, unsigned long end, |
| nodemask_t *nodes, unsigned long flags, |
| struct list_head *pagelist) |
| { |
| int err; |
| struct queue_pages qp = { |
| .pagelist = pagelist, |
| .flags = flags, |
| .nmask = nodes, |
| .start = start, |
| .end = end, |
| .first = NULL, |
| }; |
| const struct mm_walk_ops *ops = (flags & MPOL_MF_WRLOCK) ? |
| &queue_pages_lock_vma_walk_ops : &queue_pages_walk_ops; |
| |
| err = walk_page_range(mm, start, end, ops, &qp); |
| |
| if (!qp.first) |
| /* whole range in hole */ |
| err = -EFAULT; |
| |
| return err ? : qp.nr_failed; |
| } |
| |
| /* |
| * Apply policy to a single VMA |
| * This must be called with the mmap_lock held for writing. |
| */ |
| static int vma_replace_policy(struct vm_area_struct *vma, |
| struct mempolicy *pol) |
| { |
| int err; |
| struct mempolicy *old; |
| struct mempolicy *new; |
| |
| vma_assert_write_locked(vma); |
| |
| new = mpol_dup(pol); |
| if (IS_ERR(new)) |
| return PTR_ERR(new); |
| |
| if (vma->vm_ops && vma->vm_ops->set_policy) { |
| err = vma->vm_ops->set_policy(vma, new); |
| if (err) |
| goto err_out; |
| } |
| |
| old = vma->vm_policy; |
| vma->vm_policy = new; /* protected by mmap_lock */ |
| mpol_put(old); |
| |
| return 0; |
| err_out: |
| mpol_put(new); |
| return err; |
| } |
| |
| /* Split or merge the VMA (if required) and apply the new policy */ |
| static int mbind_range(struct vma_iterator *vmi, struct vm_area_struct *vma, |
| struct vm_area_struct **prev, unsigned long start, |
| unsigned long end, struct mempolicy *new_pol) |
| { |
| unsigned long vmstart, vmend; |
| |
| vmend = min(end, vma->vm_end); |
| if (start > vma->vm_start) { |
| *prev = vma; |
| vmstart = start; |
| } else { |
| vmstart = vma->vm_start; |
| } |
| |
| if (mpol_equal(vma->vm_policy, new_pol)) { |
| *prev = vma; |
| return 0; |
| } |
| |
| vma = vma_modify_policy(vmi, *prev, vma, vmstart, vmend, new_pol); |
| if (IS_ERR(vma)) |
| return PTR_ERR(vma); |
| |
| *prev = vma; |
| return vma_replace_policy(vma, new_pol); |
| } |
| |
| /* Set the process memory policy */ |
| static long do_set_mempolicy(unsigned short mode, unsigned short flags, |
| nodemask_t *nodes) |
| { |
| struct mempolicy *new, *old; |
| NODEMASK_SCRATCH(scratch); |
| int ret; |
| |
| if (!scratch) |
| return -ENOMEM; |
| |
| new = mpol_new(mode, flags, nodes); |
| if (IS_ERR(new)) { |
| ret = PTR_ERR(new); |
| goto out; |
| } |
| |
| task_lock(current); |
| ret = mpol_set_nodemask(new, nodes, scratch); |
| if (ret) { |
| task_unlock(current); |
| mpol_put(new); |
| goto out; |
| } |
| |
| old = current->mempolicy; |
| current->mempolicy = new; |
| if (new && (new->mode == MPOL_INTERLEAVE || |
| new->mode == MPOL_WEIGHTED_INTERLEAVE)) { |
| current->il_prev = MAX_NUMNODES-1; |
| current->il_weight = 0; |
| } |
| task_unlock(current); |
| mpol_put(old); |
| ret = 0; |
| out: |
| NODEMASK_SCRATCH_FREE(scratch); |
| return ret; |
| } |
| |
| /* |
| * Return nodemask for policy for get_mempolicy() query |
| * |
| * Called with task's alloc_lock held |
| */ |
| static void get_policy_nodemask(struct mempolicy *pol, nodemask_t *nodes) |
| { |
| nodes_clear(*nodes); |
| if (pol == &default_policy) |
| return; |
| |
| switch (pol->mode) { |
| case MPOL_BIND: |
| case MPOL_INTERLEAVE: |
| case MPOL_PREFERRED: |
| case MPOL_PREFERRED_MANY: |
| case MPOL_WEIGHTED_INTERLEAVE: |
| *nodes = pol->nodes; |
| break; |
| case MPOL_LOCAL: |
| /* return empty node mask for local allocation */ |
| break; |
| default: |
| BUG(); |
| } |
| } |
| |
| static int lookup_node(struct mm_struct *mm, unsigned long addr) |
| { |
| struct page *p = NULL; |
| int ret; |
| |
| ret = get_user_pages_fast(addr & PAGE_MASK, 1, 0, &p); |
| if (ret > 0) { |
| ret = page_to_nid(p); |
| put_page(p); |
| } |
| return ret; |
| } |
| |
| /* Retrieve NUMA policy */ |
| static long do_get_mempolicy(int *policy, nodemask_t *nmask, |
| unsigned long addr, unsigned long flags) |
| { |
| int err; |
| struct mm_struct *mm = current->mm; |
| struct vm_area_struct *vma = NULL; |
| struct mempolicy *pol = current->mempolicy, *pol_refcount = NULL; |
| |
| if (flags & |
| ~(unsigned long)(MPOL_F_NODE|MPOL_F_ADDR|MPOL_F_MEMS_ALLOWED)) |
| return -EINVAL; |
| |
| if (flags & MPOL_F_MEMS_ALLOWED) { |
| if (flags & (MPOL_F_NODE|MPOL_F_ADDR)) |
| return -EINVAL; |
| *policy = 0; /* just so it's initialized */ |
| task_lock(current); |
| *nmask = cpuset_current_mems_allowed; |
| task_unlock(current); |
| return 0; |
| } |
| |
| if (flags & MPOL_F_ADDR) { |
| pgoff_t ilx; /* ignored here */ |
| /* |
| * Do NOT fall back to task policy if the |
| * vma/shared policy at addr is NULL. We |
| * want to return MPOL_DEFAULT in this case. |
| */ |
| mmap_read_lock(mm); |
| vma = vma_lookup(mm, addr); |
| if (!vma) { |
| mmap_read_unlock(mm); |
| return -EFAULT; |
| } |
| pol = __get_vma_policy(vma, addr, &ilx); |
| } else if (addr) |
| return -EINVAL; |
| |
| if (!pol) |
| pol = &default_policy; /* indicates default behavior */ |
| |
| if (flags & MPOL_F_NODE) { |
| if (flags & MPOL_F_ADDR) { |
| /* |
| * Take a refcount on the mpol, because we are about to |
| * drop the mmap_lock, after which only "pol" remains |
| * valid, "vma" is stale. |
| */ |
| pol_refcount = pol; |
| vma = NULL; |
| mpol_get(pol); |
| mmap_read_unlock(mm); |
| err = lookup_node(mm, addr); |
| if (err < 0) |
| goto out; |
| *policy = err; |
| } else if (pol == current->mempolicy && |
| pol->mode == MPOL_INTERLEAVE) { |
| *policy = next_node_in(current->il_prev, pol->nodes); |
| } else if (pol == current->mempolicy && |
| pol->mode == MPOL_WEIGHTED_INTERLEAVE) { |
| if (current->il_weight) |
| *policy = current->il_prev; |
| else |
| *policy = next_node_in(current->il_prev, |
| pol->nodes); |
| } else { |
| err = -EINVAL; |
| goto out; |
| } |
| } else { |
| *policy = pol == &default_policy ? MPOL_DEFAULT : |
| pol->mode; |
| /* |
| * Internal mempolicy flags must be masked off before exposing |
| * the policy to userspace. |
| */ |
| *policy |= (pol->flags & MPOL_MODE_FLAGS); |
| } |
| |
| err = 0; |
| if (nmask) { |
| if (mpol_store_user_nodemask(pol)) { |
| *nmask = pol->w.user_nodemask; |
| } else { |
| task_lock(current); |
| get_policy_nodemask(pol, nmask); |
| task_unlock(current); |
| } |
| } |
| |
| out: |
| mpol_cond_put(pol); |
| if (vma) |
| mmap_read_unlock(mm); |
| if (pol_refcount) |
| mpol_put(pol_refcount); |
| return err; |
| } |
| |
| #ifdef CONFIG_MIGRATION |
| static bool migrate_folio_add(struct folio *folio, struct list_head *foliolist, |
| unsigned long flags) |
| { |
| /* |
| * Unless MPOL_MF_MOVE_ALL, we try to avoid migrating a shared folio. |
| * Choosing not to migrate a shared folio is not counted as a failure. |
| * |
| * To check if the folio is shared, ideally we want to make sure |
| * every page is mapped to the same process. Doing that is very |
| * expensive, so check the estimated sharers of the folio instead. |
| */ |
| if ((flags & MPOL_MF_MOVE_ALL) || folio_estimated_sharers(folio) == 1) { |
| if (folio_isolate_lru(folio)) { |
| list_add_tail(&folio->lru, foliolist); |
| node_stat_mod_folio(folio, |
| NR_ISOLATED_ANON + folio_is_file_lru(folio), |
| folio_nr_pages(folio)); |
| } else { |
| /* |
| * Non-movable folio may reach here. And, there may be |
| * temporary off LRU folios or non-LRU movable folios. |
| * Treat them as unmovable folios since they can't be |
| * isolated, so they can't be moved at the moment. |
| */ |
| return false; |
| } |
| } |
| return true; |
| } |
| |
| /* |
| * Migrate pages from one node to a target node. |
| * Returns error or the number of pages not migrated. |
| */ |
| static long migrate_to_node(struct mm_struct *mm, int source, int dest, |
| int flags) |
| { |
| nodemask_t nmask; |
| struct vm_area_struct *vma; |
| LIST_HEAD(pagelist); |
| long nr_failed; |
| long err = 0; |
| struct migration_target_control mtc = { |
| .nid = dest, |
| .gfp_mask = GFP_HIGHUSER_MOVABLE | __GFP_THISNODE, |
| }; |
| |
| nodes_clear(nmask); |
| node_set(source, nmask); |
| |
| VM_BUG_ON(!(flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL))); |
| |
| mmap_read_lock(mm); |
| vma = find_vma(mm, 0); |
| |
| /* |
| * This does not migrate the range, but isolates all pages that |
| * need migration. Between passing in the full user address |
| * space range and MPOL_MF_DISCONTIG_OK, this call cannot fail, |
| * but passes back the count of pages which could not be isolated. |
| */ |
| nr_failed = queue_pages_range(mm, vma->vm_start, mm->task_size, &nmask, |
| flags | MPOL_MF_DISCONTIG_OK, &pagelist); |
| mmap_read_unlock(mm); |
| |
| if (!list_empty(&pagelist)) { |
| err = migrate_pages(&pagelist, alloc_migration_target, NULL, |
| (unsigned long)&mtc, MIGRATE_SYNC, MR_SYSCALL, NULL); |
| if (err) |
| putback_movable_pages(&pagelist); |
| } |
| |
| if (err >= 0) |
| err += nr_failed; |
| return err; |
| } |
| |
| /* |
| * Move pages between the two nodesets so as to preserve the physical |
| * layout as much as possible. |
| * |
| * Returns the number of page that could not be moved. |
| */ |
| int do_migrate_pages(struct mm_struct *mm, const nodemask_t *from, |
| const nodemask_t *to, int flags) |
| { |
| long nr_failed = 0; |
| long err = 0; |
| nodemask_t tmp; |
| |
| lru_cache_disable(); |
| |
| /* |
| * 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 scanning 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; |
| while (!nodes_empty(tmp)) { |
| int s, d; |
| int source = NUMA_NO_NODE; |
| int dest = 0; |
| |
| for_each_node_mask(s, tmp) { |
| |
| /* |
| * do_migrate_pages() tries to maintain the relative |
| * node relationship of the pages established between |
| * threads and memory areas. |
| * |
| * However if the number of source nodes is not equal to |
| * the number of destination nodes we can not preserve |
| * this node relative relationship. In that case, skip |
| * copying memory from a node that is in the destination |
| * mask. |
| * |
| * Example: [2,3,4] -> [3,4,5] moves everything. |
| * [0-7] - > [3,4,5] moves only 0,1,2,6,7. |
| */ |
| |
| if ((nodes_weight(*from) != nodes_weight(*to)) && |
| (node_isset(s, *to))) |
| continue; |
| |
| d = node_remap(s, *from, *to); |
| if (s == d) |
| continue; |
| |
| source = s; /* Node moved. Memorize */ |
| dest = d; |
| |
| /* dest not in remaining from nodes? */ |
| if (!node_isset(dest, tmp)) |
| break; |
| } |
| if (source == NUMA_NO_NODE) |
| break; |
| |
| node_clear(source, tmp); |
| err = migrate_to_node(mm, source, dest, flags); |
| if (err > 0) |
| nr_failed += err; |
| if (err < 0) |
| break; |
| } |
| |
| lru_cache_enable(); |
| if (err < 0) |
| return err; |
| return (nr_failed < INT_MAX) ? nr_failed : INT_MAX; |
| } |
| |
| /* |
| * Allocate a new folio for page migration, according to NUMA mempolicy. |
| */ |
| static struct folio *alloc_migration_target_by_mpol(struct folio *src, |
| unsigned long private) |
| { |
| struct migration_mpol *mmpol = (struct migration_mpol *)private; |
| struct mempolicy *pol = mmpol->pol; |
| pgoff_t ilx = mmpol->ilx; |
| struct page *page; |
| unsigned int order; |
| int nid = numa_node_id(); |
| gfp_t gfp; |
| |
| order = folio_order(src); |
| ilx += src->index >> order; |
| |
| if (folio_test_hugetlb(src)) { |
| nodemask_t *nodemask; |
| struct hstate *h; |
| |
| h = folio_hstate(src); |
| gfp = htlb_alloc_mask(h); |
| nodemask = policy_nodemask(gfp, pol, ilx, &nid); |
| return alloc_hugetlb_folio_nodemask(h, nid, nodemask, gfp); |
| } |
| |
| if (folio_test_large(src)) |
| gfp = GFP_TRANSHUGE; |
| else |
| gfp = GFP_HIGHUSER_MOVABLE | __GFP_RETRY_MAYFAIL | __GFP_COMP; |
| |
| page = alloc_pages_mpol(gfp, order, pol, ilx, nid); |
| return page_rmappable_folio(page); |
| } |
| #else |
| |
| static bool migrate_folio_add(struct folio *folio, struct list_head *foliolist, |
| unsigned long flags) |
| { |
| return false; |
| } |
| |
| int do_migrate_pages(struct mm_struct *mm, const nodemask_t *from, |
| const nodemask_t *to, int flags) |
| { |
| return -ENOSYS; |
| } |
| |
| static struct folio *alloc_migration_target_by_mpol(struct folio *src, |
| unsigned long private) |
| { |
| return NULL; |
| } |
| #endif |
| |
| static long do_mbind(unsigned long start, unsigned long len, |
| unsigned short mode, unsigned short mode_flags, |
| nodemask_t *nmask, unsigned long flags) |
| { |
| struct mm_struct *mm = current->mm; |
| struct vm_area_struct *vma, *prev; |
| struct vma_iterator vmi; |
| struct migration_mpol mmpol; |
| struct mempolicy *new; |
| unsigned long end; |
| long err; |
| long nr_failed; |
| LIST_HEAD(pagelist); |
| |
| if (flags & ~(unsigned long)MPOL_MF_VALID) |
| return -EINVAL; |
| if ((flags & MPOL_MF_MOVE_ALL) && !capable(CAP_SYS_NICE)) |
| return -EPERM; |
| |
| if (start & ~PAGE_MASK) |
| return -EINVAL; |
| |
| if (mode == MPOL_DEFAULT) |
| flags &= ~MPOL_MF_STRICT; |
| |
| len = PAGE_ALIGN(len); |
| end = start + len; |
| |
| if (end < start) |
| return -EINVAL; |
| if (end == start) |
| return 0; |
| |
| new = mpol_new(mode, mode_flags, nmask); |
| if (IS_ERR(new)) |
| return PTR_ERR(new); |
| |
| /* |
| * If we are using the default policy then operation |
| * on discontinuous address spaces is okay after all |
| */ |
| if (!new) |
| flags |= MPOL_MF_DISCONTIG_OK; |
| |
| if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) |
| lru_cache_disable(); |
| { |
| NODEMASK_SCRATCH(scratch); |
| if (scratch) { |
| mmap_write_lock(mm); |
| err = mpol_set_nodemask(new, nmask, scratch); |
| if (err) |
| mmap_write_unlock(mm); |
| } else |
| err = -ENOMEM; |
| NODEMASK_SCRATCH_FREE(scratch); |
| } |
| if (err) |
| goto mpol_out; |
| |
| /* |
| * Lock the VMAs before scanning for pages to migrate, |
| * to ensure we don't miss a concurrently inserted page. |
| */ |
| nr_failed = queue_pages_range(mm, start, end, nmask, |
| flags | MPOL_MF_INVERT | MPOL_MF_WRLOCK, &pagelist); |
| |
| if (nr_failed < 0) { |
| err = nr_failed; |
| nr_failed = 0; |
| } else { |
| vma_iter_init(&vmi, mm, start); |
| prev = vma_prev(&vmi); |
| for_each_vma_range(vmi, vma, end) { |
| err = mbind_range(&vmi, vma, &prev, start, end, new); |
| if (err) |
| break; |
| } |
| } |
| |
| if (!err && !list_empty(&pagelist)) { |
| /* Convert MPOL_DEFAULT's NULL to task or default policy */ |
| if (!new) { |
| new = get_task_policy(current); |
| mpol_get(new); |
| } |
| mmpol.pol = new; |
| mmpol.ilx = 0; |
| |
| /* |
| * In the interleaved case, attempt to allocate on exactly the |
| * targeted nodes, for the first VMA to be migrated; for later |
| * VMAs, the nodes will still be interleaved from the targeted |
| * nodemask, but one by one may be selected differently. |
| */ |
| if (new->mode == MPOL_INTERLEAVE || |
| new->mode == MPOL_WEIGHTED_INTERLEAVE) { |
| struct folio *folio; |
| unsigned int order; |
| unsigned long addr = -EFAULT; |
| |
| list_for_each_entry(folio, &pagelist, lru) { |
| if (!folio_test_ksm(folio)) |
| break; |
| } |
| if (!list_entry_is_head(folio, &pagelist, lru)) { |
| vma_iter_init(&vmi, mm, start); |
| for_each_vma_range(vmi, vma, end) { |
| addr = page_address_in_vma( |
| folio_page(folio, 0), vma); |
| if (addr != -EFAULT) |
| break; |
| } |
| } |
| if (addr != -EFAULT) { |
| order = folio_order(folio); |
| /* We already know the pol, but not the ilx */ |
| mpol_cond_put(get_vma_policy(vma, addr, order, |
| &mmpol.ilx)); |
| /* Set base from which to increment by index */ |
| mmpol.ilx -= folio->index >> order; |
| } |
| } |
| } |
| |
| mmap_write_unlock(mm); |
| |
| if (!err && !list_empty(&pagelist)) { |
| nr_failed |= migrate_pages(&pagelist, |
| alloc_migration_target_by_mpol, NULL, |
| (unsigned long)&mmpol, MIGRATE_SYNC, |
| MR_MEMPOLICY_MBIND, NULL); |
| } |
| |
| if (nr_failed && (flags & MPOL_MF_STRICT)) |
| err = -EIO; |
| if (!list_empty(&pagelist)) |
| putback_movable_pages(&pagelist); |
| mpol_out: |
| mpol_put(new); |
| if (flags & (MPOL_MF_MOVE | MPOL_MF_MOVE_ALL)) |
| lru_cache_enable(); |
| return err; |
| } |
| |
| /* |
| * User space interface with variable sized bitmaps for nodelists. |
| */ |
| static int get_bitmap(unsigned long *mask, const unsigned long __user *nmask, |
| unsigned long maxnode) |
| { |
| unsigned long nlongs = BITS_TO_LONGS(maxnode); |
| int ret; |
| |
| if (in_compat_syscall()) |
| ret = compat_get_bitmap(mask, |
| (const compat_ulong_t __user *)nmask, |
| maxnode); |
| else |
| ret = copy_from_user(mask, nmask, |
| nlongs * sizeof(unsigned long)); |
| |
| if (ret) |
| return -EFAULT; |
| |
| if (maxnode % BITS_PER_LONG) |
| mask[nlongs - 1] &= (1UL << (maxnode % BITS_PER_LONG)) - 1; |
| |
| return 0; |
| } |
| |
| /* Copy a node mask from user space. */ |
| static int get_nodes(nodemask_t *nodes, const unsigned long __user *nmask, |
| unsigned long maxnode) |
| { |
| --maxnode; |
| nodes_clear(*nodes); |
| if (maxnode == 0 || !nmask) |
| return 0; |
| if (maxnode > PAGE_SIZE*BITS_PER_BYTE) |
| return -EINVAL; |
| |
| /* |
| * When the user specified more nodes than supported just check |
| * if the non supported part is all zero, one word at a time, |
| * starting at the end. |
| */ |
| while (maxnode > MAX_NUMNODES) { |
| unsigned long bits = min_t(unsigned long, maxnode, BITS_PER_LONG); |
| unsigned long t; |
| |
| if (get_bitmap(&t, &nmask[(maxnode - 1) / BITS_PER_LONG], bits)) |
| return -EFAULT; |
| |
| if (maxnode - bits >= MAX_NUMNODES) { |
| maxnode -= bits; |
| } else { |
| maxnode = MAX_NUMNODES; |
| t &= ~((1UL << (MAX_NUMNODES % BITS_PER_LONG)) - 1); |
| } |
| if (t) |
| return -EINVAL; |
| } |
| |
| return get_bitmap(nodes_addr(*nodes), nmask, maxnode); |
| } |
| |
| /* Copy a kernel node mask to user space */ |
| static int copy_nodes_to_user(unsigned long __user *mask, unsigned long maxnode, |
| nodemask_t *nodes) |
| { |
| unsigned long copy = ALIGN(maxnode-1, 64) / 8; |
| unsigned int nbytes = BITS_TO_LONGS(nr_node_ids) * sizeof(long); |
| bool compat = in_compat_syscall(); |
| |
| if (compat) |
| nbytes = BITS_TO_COMPAT_LONGS(nr_node_ids) * sizeof(compat_long_t); |
| |
| if (copy > nbytes) { |
| if (copy > PAGE_SIZE) |
| return -EINVAL; |
| if (clear_user((char __user *)mask + nbytes, copy - nbytes)) |
| return -EFAULT; |
| copy = nbytes; |
| maxnode = nr_node_ids; |
| } |
| |
| if (compat) |
| return compat_put_bitmap((compat_ulong_t __user *)mask, |
| nodes_addr(*nodes), maxnode); |
| |
| return copy_to_user(mask, nodes_addr(*nodes), copy) ? -EFAULT : 0; |
| } |
| |
| /* Basic parameter sanity check used by both mbind() and set_mempolicy() */ |
| static inline int sanitize_mpol_flags(int *mode, unsigned short *flags) |
| { |
| *flags = *mode & MPOL_MODE_FLAGS; |
| *mode &= ~MPOL_MODE_FLAGS; |
| |
| if ((unsigned int)(*mode) >= MPOL_MAX) |
| return -EINVAL; |
| if ((*flags & MPOL_F_STATIC_NODES) && (*flags & MPOL_F_RELATIVE_NODES)) |
| return -EINVAL; |
| if (*flags & MPOL_F_NUMA_BALANCING) { |
| if (*mode != MPOL_BIND) |
| return -EINVAL; |
| *flags |= (MPOL_F_MOF | MPOL_F_MORON); |
| } |
| return 0; |
| } |
| |
| static long kernel_mbind(unsigned long start, unsigned long len, |
| unsigned long mode, const unsigned long __user *nmask, |
| unsigned long maxnode, unsigned int flags) |
| { |
| unsigned short mode_flags; |
| nodemask_t nodes; |
| int lmode = mode; |
| int err; |
| |
| start = untagged_addr(start); |
| err = sanitize_mpol_flags(&lmode, &mode_flags); |
| if (err) |
| return err; |
| |
| err = get_nodes(&nodes, nmask, maxnode); |
| if (err) |
| return err; |
| |
| return do_mbind(start, len, lmode, mode_flags, &nodes, flags); |
| } |
| |
| SYSCALL_DEFINE4(set_mempolicy_home_node, unsigned long, start, unsigned long, len, |
| unsigned long, home_node, unsigned long, flags) |
| { |
| struct mm_struct *mm = current->mm; |
| struct vm_area_struct *vma, *prev; |
| struct mempolicy *new, *old; |
| unsigned long end; |
| int err = -ENOENT; |
| VMA_ITERATOR(vmi, mm, start); |
| |
| start = untagged_addr(start); |
| if (start & ~PAGE_MASK) |
| return -EINVAL; |
| /* |
| * flags is used for future extension if any. |
| */ |
| if (flags != 0) |
| return -EINVAL; |
| |
| /* |
| * Check home_node is online to avoid accessing uninitialized |
| * NODE_DATA. |
| */ |
| if (home_node >= MAX_NUMNODES || !node_online(home_node)) |
| return -EINVAL; |
| |
| len = PAGE_ALIGN(len); |
| end = start + len; |
| |
| if (end < start) |
| return -EINVAL; |
| if (end == start) |
| return 0; |
| mmap_write_lock(mm); |
| prev = vma_prev(&vmi); |
| for_each_vma_range(vmi, vma, end) { |
| /* |
| * If any vma in the range got policy other than MPOL_BIND |
| * or MPOL_PREFERRED_MANY we return error. We don't reset |
| * the home node for vmas we already updated before. |
| */ |
| old = vma_policy(vma); |
| if (!old) { |
| prev = vma; |
| continue; |
| } |
| if (old->mode != MPOL_BIND && old->mode != MPOL_PREFERRED_MANY) { |
| err = -EOPNOTSUPP; |
| break; |
| } |
| new = mpol_dup(old); |
| if (IS_ERR(new)) { |
| err = PTR_ERR(new); |
| break; |
| } |
| |
| vma_start_write(vma); |
| new->home_node = home_node; |
| err = mbind_range(&vmi, vma, &prev, start, end, new); |
| mpol_put(new); |
| if (err) |
| break; |
| } |
| mmap_write_unlock(mm); |
| return err; |
| } |
| |
| SYSCALL_DEFINE6(mbind, unsigned long, start, unsigned long, len, |
| unsigned long, mode, const unsigned long __user *, nmask, |
| unsigned long, maxnode, unsigned int, flags) |
| { |
| return kernel_mbind(start, len, mode, nmask, maxnode, flags); |
| } |
| |
| /* Set the process memory policy */ |
| static long kernel_set_mempolicy(int mode, const unsigned long __user *nmask, |
| unsigned long maxnode) |
| { |
| unsigned short mode_flags; |
| nodemask_t nodes; |
| int lmode = mode; |
| int err; |
| |
| err = sanitize_mpol_flags(&lmode, &mode_flags); |
| if (err) |
| return err; |
| |
| err = get_nodes(&nodes, nmask, maxnode); |
| if (err) |
| return err; |
| |
| return do_set_mempolicy(lmode, mode_flags, &nodes); |
| } |
| |
| SYSCALL_DEFINE3(set_mempolicy, int, mode, const unsigned long __user *, nmask, |
| unsigned long, maxnode) |
| { |
| return kernel_set_mempolicy(mode, nmask, maxnode); |
| } |
| |
| static int kernel_migrate_pages(pid_t pid, unsigned long maxnode, |
| const unsigned long __user *old_nodes, |
| const unsigned long __user *new_nodes) |
| { |
| struct mm_struct *mm = NULL; |
| struct task_struct *task; |
| nodemask_t task_nodes; |
| int err; |
| nodemask_t *old; |
| nodemask_t *new; |
| NODEMASK_SCRATCH(scratch); |
| |
| if (!scratch) |
| return -ENOMEM; |
| |
| old = &scratch->mask1; |
| new = &scratch->mask2; |
| |
| err = get_nodes(old, old_nodes, maxnode); |
| if (err) |
| goto out; |
| |
| err = get_nodes(new, new_nodes, maxnode); |
| if (err) |
| goto out; |
| |
| /* Find the mm_struct */ |
| rcu_read_lock(); |
| task = pid ? find_task_by_vpid(pid) : current; |
| if (!task) { |
| rcu_read_unlock(); |
| err = -ESRCH; |
| goto out; |
| } |
| get_task_struct(task); |
| |
| err = -EINVAL; |
| |
| /* |
| * Check if this process has the right to modify the specified process. |
| * Use the regular "ptrace_may_access()" checks. |
| */ |
| if (!ptrace_may_access(task, PTRACE_MODE_READ_REALCREDS)) { |
| rcu_read_unlock(); |
| err = -EPERM; |
| goto out_put; |
| } |
| rcu_read_unlock(); |
| |
| task_nodes = cpuset_mems_allowed(task); |
| /* Is the user allowed to access the target nodes? */ |
| if (!nodes_subset(*new, task_nodes) && !capable(CAP_SYS_NICE)) { |
| err = -EPERM; |
| goto out_put; |
| } |
| |
| task_nodes = cpuset_mems_allowed(current); |
| nodes_and(*new, *new, task_nodes); |
| if (nodes_empty(*new)) |
| goto out_put; |
| |
| err = security_task_movememory(task); |
| if (err) |
| goto out_put; |
| |
| mm = get_task_mm(task); |
| put_task_struct(task); |
| |
| if (!mm) { |
| err = -EINVAL; |
| goto out; |
| } |
| |
| err = do_migrate_pages(mm, old, new, |
| capable(CAP_SYS_NICE) ? MPOL_MF_MOVE_ALL : MPOL_MF_MOVE); |
| |
| mmput(mm); |
| out: |
| NODEMASK_SCRATCH_FREE(scratch); |
| |
| return err; |
| |
| out_put: |
| put_task_struct(task); |
| goto out; |
| } |
| |
| SYSCALL_DEFINE4(migrate_pages, pid_t, pid, unsigned long, maxnode, |
| const unsigned long __user *, old_nodes, |
| const unsigned long __user *, new_nodes) |
| { |
| return kernel_migrate_pages(pid, maxnode, old_nodes, new_nodes); |
| } |
| |
| /* Retrieve NUMA policy */ |
| static int kernel_get_mempolicy(int __user *policy, |
| unsigned long __user *nmask, |
| unsigned long maxnode, |
| unsigned long addr, |
| unsigned long flags) |
| { |
| int err; |
| int pval; |
| nodemask_t nodes; |
| |
| if (nmask != NULL && maxnode < nr_node_ids) |
| return -EINVAL; |
| |
| addr = untagged_addr(addr); |
| |
| err = do_get_mempolicy(&pval, &nodes, addr, flags); |
| |
| if (err) |
| return err; |
| |
| if (policy && put_user(pval, policy)) |
| return -EFAULT; |
| |
| if (nmask) |
| err = copy_nodes_to_user(nmask, maxnode, &nodes); |
| |
| return err; |
| } |
| |
| SYSCALL_DEFINE5(get_mempolicy, int __user *, policy, |
| unsigned long __user *, nmask, unsigned long, maxnode, |
| unsigned long, addr, unsigned long, flags) |
| { |
| return kernel_get_mempolicy(policy, nmask, maxnode, addr, flags); |
| } |
| |
| bool vma_migratable(struct vm_area_struct *vma) |
| { |
| if (vma->vm_flags & (VM_IO | VM_PFNMAP)) |
| return false; |
| |
| /* |
| * DAX device mappings require predictable access latency, so avoid |
| * incurring periodic faults. |
| */ |
| if (vma_is_dax(vma)) |
| return false; |
| |
| if (is_vm_hugetlb_page(vma) && |
| !hugepage_migration_supported(hstate_vma(vma))) |
| return false; |
| |
| /* |
| * Migration allocates pages in the highest zone. If we cannot |
| * do so then migration (at least from node to node) is not |
| * possible. |
| */ |
| if (vma->vm_file && |
| gfp_zone(mapping_gfp_mask(vma->vm_file->f_mapping)) |
| < policy_zone) |
| return false; |
| return true; |
| } |
| |
| struct mempolicy *__get_vma_policy(struct vm_area_struct *vma, |
| unsigned long addr, pgoff_t *ilx) |
| { |
| *ilx = 0; |
| return (vma->vm_ops && vma->vm_ops->get_policy) ? |
| vma->vm_ops->get_policy(vma, addr, ilx) : vma->vm_policy; |
| } |
| |
| /* |
| * get_vma_policy(@vma, @addr, @order, @ilx) |
| * @vma: virtual memory area whose policy is sought |
| * @addr: address in @vma for shared policy lookup |
| * @order: 0, or appropriate huge_page_order for interleaving |
| * @ilx: interleave index (output), for use only when MPOL_INTERLEAVE or |
| * MPOL_WEIGHTED_INTERLEAVE |
| * |
| * Returns effective policy for a VMA at specified address. |
| * Falls back to current->mempolicy or system default policy, as necessary. |
| * Shared policies [those marked as MPOL_F_SHARED] require an extra reference |
| * count--added by the get_policy() vm_op, as appropriate--to protect against |
| * freeing by another task. It is the caller's responsibility to free the |
| * extra reference for shared policies. |
| */ |
| struct mempolicy *get_vma_policy(struct vm_area_struct *vma, |
| unsigned long addr, int order, pgoff_t *ilx) |
| { |
| struct mempolicy *pol; |
| |
| pol = __get_vma_policy(vma, addr, ilx); |
| if (!pol) |
| pol = get_task_policy(current); |
| if (pol->mode == MPOL_INTERLEAVE || |
| pol->mode == MPOL_WEIGHTED_INTERLEAVE) { |
| *ilx += vma->vm_pgoff >> order; |
| *ilx += (addr - vma->vm_start) >> (PAGE_SHIFT + order); |
| } |
| return pol; |
| } |
| |
| bool vma_policy_mof(struct vm_area_struct *vma) |
| { |
| struct mempolicy *pol; |
| |
| if (vma->vm_ops && vma->vm_ops->get_policy) { |
| bool ret = false; |
| pgoff_t ilx; /* ignored here */ |
| |
| pol = vma->vm_ops->get_policy(vma, vma->vm_start, &ilx); |
| if (pol && (pol->flags & MPOL_F_MOF)) |
| ret = true; |
| mpol_cond_put(pol); |
| |
| return ret; |
| } |
| |
| pol = vma->vm_policy; |
| if (!pol) |
| pol = get_task_policy(current); |
| |
| return pol->flags & MPOL_F_MOF; |
| } |
| |
| bool apply_policy_zone(struct mempolicy *policy, enum zone_type zone) |
| { |
| enum zone_type dynamic_policy_zone = policy_zone; |
| |
| BUG_ON(dynamic_policy_zone == ZONE_MOVABLE); |
| |
| /* |
| * if policy->nodes has movable memory only, |
| * we apply policy when gfp_zone(gfp) = ZONE_MOVABLE only. |
| * |
| * policy->nodes is intersect with node_states[N_MEMORY]. |
| * so if the following test fails, it implies |
| * policy->nodes has movable memory only. |
| */ |
| if (!nodes_intersects(policy->nodes, node_states[N_HIGH_MEMORY])) |
| dynamic_policy_zone = ZONE_MOVABLE; |
| |
| return zone >= dynamic_policy_zone; |
| } |
| |
| static unsigned int weighted_interleave_nodes(struct mempolicy *policy) |
| { |
| unsigned int node; |
| unsigned int cpuset_mems_cookie; |
| |
| retry: |
| /* to prevent miscount use tsk->mems_allowed_seq to detect rebind */ |
| cpuset_mems_cookie = read_mems_allowed_begin(); |
| node = current->il_prev; |
| if (!current->il_weight || !node_isset(node, policy->nodes)) { |
| node = next_node_in(node, policy->nodes); |
| if (read_mems_allowed_retry(cpuset_mems_cookie)) |
| goto retry; |
| if (node == MAX_NUMNODES) |
| return node; |
| current->il_prev = node; |
| current->il_weight = get_il_weight(node); |
| } |
| current->il_weight--; |
| return node; |
| } |
| |
| /* Do dynamic interleaving for a process */ |
| static unsigned int interleave_nodes(struct mempolicy *policy) |
| { |
| unsigned int nid; |
| unsigned int cpuset_mems_cookie; |
| |
| /* to prevent miscount, use tsk->mems_allowed_seq to detect rebind */ |
| do { |
| cpuset_mems_cookie = read_mems_allowed_begin(); |
| nid = next_node_in(current->il_prev, policy->nodes); |
| } while (read_mems_allowed_retry(cpuset_mems_cookie)); |
| |
| if (nid < MAX_NUMNODES) |
| current->il_prev = nid; |
| return nid; |
| } |
| |
| /* |
| * Depending on the memory policy provide a node from which to allocate the |
| * next slab entry. |
| */ |
| unsigned int mempolicy_slab_node(void) |
| { |
| struct mempolicy *policy; |
| int node = numa_mem_id(); |
| |
| if (!in_task()) |
| return node; |
| |
| policy = current->mempolicy; |
| if (!policy) |
| return node; |
| |
| switch (policy->mode) { |
| case MPOL_PREFERRED: |
| return first_node(policy->nodes); |
| |
| case MPOL_INTERLEAVE: |
| return interleave_nodes(policy); |
| |
| case MPOL_WEIGHTED_INTERLEAVE: |
| return weighted_interleave_nodes(policy); |
| |
| case MPOL_BIND: |
| case MPOL_PREFERRED_MANY: |
| { |
| struct zoneref *z; |
| |
| /* |
| * Follow bind policy behavior and start allocation at the |
| * first node. |
| */ |
| struct zonelist *zonelist; |
| enum zone_type highest_zoneidx = gfp_zone(GFP_KERNEL); |
| zonelist = &NODE_DATA(node)->node_zonelists[ZONELIST_FALLBACK]; |
| z = first_zones_zonelist(zonelist, highest_zoneidx, |
| &policy->nodes); |
| return z->zone ? zone_to_nid(z->zone) : node; |
| } |
| case MPOL_LOCAL: |
| return node; |
| |
| default: |
| BUG(); |
| } |
| } |
| |
| static unsigned int read_once_policy_nodemask(struct mempolicy *pol, |
| nodemask_t *mask) |
| { |
| /* |
| * barrier stabilizes the nodemask locally so that it can be iterated |
| * over safely without concern for changes. Allocators validate node |
| * selection does not violate mems_allowed, so this is safe. |
| */ |
| barrier(); |
| memcpy(mask, &pol->nodes, sizeof(nodemask_t)); |
| barrier(); |
| return nodes_weight(*mask); |
| } |
| |
| static unsigned int weighted_interleave_nid(struct mempolicy *pol, pgoff_t ilx) |
| { |
| nodemask_t nodemask; |
| unsigned int target, nr_nodes; |
| u8 *table; |
| unsigned int weight_total = 0; |
| u8 weight; |
| int nid; |
| |
| nr_nodes = read_once_policy_nodemask(pol, &nodemask); |
| if (!nr_nodes) |
| return numa_node_id(); |
| |
| rcu_read_lock(); |
| table = rcu_dereference(iw_table); |
| /* calculate the total weight */ |
| for_each_node_mask(nid, nodemask) { |
| /* detect system default usage */ |
| weight = table ? table[nid] : 1; |
| weight = weight ? weight : 1; |
| weight_total += weight; |
| } |
| |
| /* Calculate the node offset based on totals */ |
| target = ilx % weight_total; |
| nid = first_node(nodemask); |
| while (target) { |
| /* detect system default usage */ |
| weight = table ? table[nid] : 1; |
| weight = weight ? weight : 1; |
| if (target < weight) |
| break; |
| target -= weight; |
| nid = next_node_in(nid, nodemask); |
| } |
| rcu_read_unlock(); |
| return nid; |
| } |
| |
| /* |
| * Do static interleaving for interleave index @ilx. Returns the ilx'th |
| * node in pol->nodes (starting from ilx=0), wrapping around if ilx |
| * exceeds the number of present nodes. |
| */ |
| static unsigned int interleave_nid(struct mempolicy *pol, pgoff_t ilx) |
| { |
| nodemask_t nodemask; |
| unsigned int target, nnodes; |
| int i; |
| int nid; |
| |
| nnodes = read_once_policy_nodemask(pol, &nodemask); |
| if (!nnodes) |
| return numa_node_id(); |
| target = ilx % nnodes; |
| nid = first_node(nodemask); |
| for (i = 0; i < target; i++) |
| nid = next_node(nid, nodemask); |
| return nid; |
| } |
| |
| /* |
| * Return a nodemask representing a mempolicy for filtering nodes for |
| * page allocation, together with preferred node id (or the input node id). |
| */ |
| static nodemask_t *policy_nodemask(gfp_t gfp, struct mempolicy *pol, |
| pgoff_t ilx, int *nid) |
| { |
| nodemask_t *nodemask = NULL; |
| |
| switch (pol->mode) { |
| case MPOL_PREFERRED: |
| /* Override input node id */ |
| *nid = first_node(pol->nodes); |
| break; |
| case MPOL_PREFERRED_MANY: |
| nodemask = &pol->nodes; |
| if (pol->home_node != NUMA_NO_NODE) |
| *nid = pol->home_node; |
| break; |
| case MPOL_BIND: |
| /* Restrict to nodemask (but not on lower zones) */ |
| if (apply_policy_zone(pol, gfp_zone(gfp)) && |
| cpuset_nodemask_valid_mems_allowed(&pol->nodes)) |
| nodemask = &pol->nodes; |
| if (pol->home_node != NUMA_NO_NODE) |
| *nid = pol->home_node; |
| /* |
| * __GFP_THISNODE shouldn't even be used with the bind policy |
| * because we might easily break the expectation to stay on the |
| * requested node and not break the policy. |
| */ |
| WARN_ON_ONCE(gfp & __GFP_THISNODE); |
| break; |
| case MPOL_INTERLEAVE: |
| /* Override input node id */ |
| *nid = (ilx == NO_INTERLEAVE_INDEX) ? |
| interleave_nodes(pol) : interleave_nid(pol, ilx); |
| break; |
| case MPOL_WEIGHTED_INTERLEAVE: |
| *nid = (ilx == NO_INTERLEAVE_INDEX) ? |
| weighted_interleave_nodes(pol) : |
| weighted_interleave_nid(pol, ilx); |
| break; |
| } |
| |
| return nodemask; |
| } |
| |
| #ifdef CONFIG_HUGETLBFS |
| /* |
| * huge_node(@vma, @addr, @gfp_flags, @mpol) |
| * @vma: virtual memory area whose policy is sought |
| * @addr: address in @vma for shared policy lookup and interleave policy |
| * @gfp_flags: for requested zone |
| * @mpol: pointer to mempolicy pointer for reference counted mempolicy |
| * @nodemask: pointer to nodemask pointer for 'bind' and 'prefer-many' policy |
| * |
| * Returns a nid suitable for a huge page allocation and a pointer |
| * to the struct mempolicy for conditional unref after allocation. |
| * If the effective policy is 'bind' or 'prefer-many', returns a pointer |
| * to the mempolicy's @nodemask for filtering the zonelist. |
| */ |
| int huge_node(struct vm_area_struct *vma, unsigned long addr, gfp_t gfp_flags, |
| struct mempolicy **mpol, nodemask_t **nodemask) |
| { |
| pgoff_t ilx; |
| int nid; |
| |
| nid = numa_node_id(); |
| *mpol = get_vma_policy(vma, addr, hstate_vma(vma)->order, &ilx); |
| *nodemask = policy_nodemask(gfp_flags, *mpol, ilx, &nid); |
| return nid; |
| } |
| |
| /* |
| * 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; |
| |
| if (!(mask && current->mempolicy)) |
| return false; |
| |
| task_lock(current); |
| mempolicy = current->mempolicy; |
| switch (mempolicy->mode) { |
| case MPOL_PREFERRED: |
| case MPOL_PREFERRED_MANY: |
| case MPOL_BIND: |
| case MPOL_INTERLEAVE: |
| case MPOL_WEIGHTED_INTERLEAVE: |
| *mask = mempolicy->nodes; |
| break; |
| |
| case MPOL_LOCAL: |
| init_nodemask_of_node(mask, numa_node_id()); |
| break; |
| |
| default: |
| BUG(); |
| } |
| task_unlock(current); |
| |
| return true; |
| } |
| #endif |
| |
| /* |
| * mempolicy_in_oom_domain |
| * |
| * If tsk's mempolicy is "bind", check for intersection between mask and |
| * the policy nodemask. Otherwise, return true for all other policies |
| * including "interleave", as a tsk with "interleave" policy may have |
| * memory allocated from all nodes in system. |
| * |
| * Takes task_lock(tsk) to prevent freeing of its mempolicy. |
| */ |
| bool mempolicy_in_oom_domain(struct task_struct *tsk, |
| const nodemask_t *mask) |
| { |
| struct mempolicy *mempolicy; |
| bool ret = true; |
| |
| if (!mask) |
| return ret; |
| |
| task_lock(tsk); |
| mempolicy = tsk->mempolicy; |
| if (mempolicy && mempolicy->mode == MPOL_BIND) |
| ret = nodes_intersects(mempolicy->nodes, *mask); |
| task_unlock(tsk); |
| |
| return ret; |
| } |
| |
| static struct page *alloc_pages_preferred_many(gfp_t gfp, unsigned int order, |
| int nid, nodemask_t *nodemask) |
| { |
| struct page *page; |
| gfp_t preferred_gfp; |
| |
| /* |
| * This is a two pass approach. The first pass will only try the |
| * preferred nodes but skip the direct reclaim and allow the |
| * allocation to fail, while the second pass will try all the |
| * nodes in system. |
| */ |
| preferred_gfp = gfp | __GFP_NOWARN; |
| preferred_gfp &= ~(__GFP_DIRECT_RECLAIM | __GFP_NOFAIL); |
| page = __alloc_pages(preferred_gfp, order, nid, nodemask); |
| if (!page) |
| page = __alloc_pages(gfp, order, nid, NULL); |
| |
| return page; |
| } |
| |
| /** |
| * alloc_pages_mpol - Allocate pages according to NUMA mempolicy. |
| * @gfp: GFP flags. |
| * @order: Order of the page allocation. |
| * @pol: Pointer to the NUMA mempolicy. |
| * @ilx: Index for interleave mempolicy (also distinguishes alloc_pages()). |
| * @nid: Preferred node (usually numa_node_id() but @mpol may override it). |
| * |
| * Return: The page on success or NULL if allocation fails. |
| */ |
| struct page *alloc_pages_mpol(gfp_t gfp, unsigned int order, |
| struct mempolicy *pol, pgoff_t ilx, int nid) |
| { |
| nodemask_t *nodemask; |
| struct page *page; |
| |
| nodemask = policy_nodemask(gfp, pol, ilx, &nid); |
| |
| if (pol->mode == MPOL_PREFERRED_MANY) |
| return alloc_pages_preferred_many(gfp, order, nid, nodemask); |
| |
| if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && |
| /* filter "hugepage" allocation, unless from alloc_pages() */ |
| order == HPAGE_PMD_ORDER && ilx != NO_INTERLEAVE_INDEX) { |
| /* |
| * For hugepage allocation and non-interleave policy which |
| * allows the current node (or other explicitly preferred |
| * node) we only try to allocate from the current/preferred |
| * node and don't fall back to other nodes, as the cost of |
| * remote accesses would likely offset THP benefits. |
| * |
| * If the policy is interleave or does not allow the current |
| * node in its nodemask, we allocate the standard way. |
| */ |
| if (pol->mode != MPOL_INTERLEAVE && |
| pol->mode != MPOL_WEIGHTED_INTERLEAVE && |
| (!nodemask || node_isset(nid, *nodemask))) { |
| /* |
| * First, try to allocate THP only on local node, but |
| * don't reclaim unnecessarily, just compact. |
| */ |
| page = __alloc_pages_node(nid, |
| gfp | __GFP_THISNODE | __GFP_NORETRY, order); |
| if (page || !(gfp & __GFP_DIRECT_RECLAIM)) |
| return page; |
| /* |
| * If hugepage allocations are configured to always |
| * synchronous compact or the vma has been madvised |
| * to prefer hugepage backing, retry allowing remote |
| * memory with both reclaim and compact as well. |
| */ |
| } |
| } |
| |
| page = __alloc_pages(gfp, order, nid, nodemask); |
| |
| if (unlikely(pol->mode == MPOL_INTERLEAVE) && page) { |
| /* skip NUMA_INTERLEAVE_HIT update if numa stats is disabled */ |
| if (static_branch_likely(&vm_numa_stat_key) && |
| page_to_nid(page) == nid) { |
| preempt_disable(); |
| __count_numa_event(page_zone(page), NUMA_INTERLEAVE_HIT); |
| preempt_enable(); |
| } |
| } |
| |
| return page; |
| } |
| |
| /** |
| * vma_alloc_folio - Allocate a folio for a VMA. |
| * @gfp: GFP flags. |
| * @order: Order of the folio. |
| * @vma: Pointer to VMA. |
| * @addr: Virtual address of the allocation. Must be inside @vma. |
| * @hugepage: Unused (was: For hugepages try only preferred node if possible). |
| * |
| * Allocate a folio for a specific address in @vma, using the appropriate |
| * NUMA policy. The caller must hold the mmap_lock of the mm_struct of the |
| * VMA to prevent it from going away. Should be used for all allocations |
| * for folios that will be mapped into user space, excepting hugetlbfs, and |
| * excepting where direct use of alloc_pages_mpol() is more appropriate. |
| * |
| * Return: The folio on success or NULL if allocation fails. |
| */ |
| struct folio *vma_alloc_folio(gfp_t gfp, int order, struct vm_area_struct *vma, |
| unsigned long addr, bool hugepage) |
| { |
| struct mempolicy *pol; |
| pgoff_t ilx; |
| struct page *page; |
| |
| pol = get_vma_policy(vma, addr, order, &ilx); |
| page = alloc_pages_mpol(gfp | __GFP_COMP, order, |
| pol, ilx, numa_node_id()); |
| mpol_cond_put(pol); |
| return page_rmappable_folio(page); |
| } |
| EXPORT_SYMBOL(vma_alloc_folio); |
| |
| /** |
| * alloc_pages - Allocate pages. |
| * @gfp: GFP flags. |
| * @order: Power of two of number of pages to allocate. |
| * |
| * Allocate 1 << @order contiguous pages. The physical address of the |
| * first page is naturally aligned (eg an order-3 allocation will be aligned |
| * to a multiple of 8 * PAGE_SIZE bytes). The NUMA policy of the current |
| * process is honoured when in process context. |
| * |
| * Context: Can be called from any context, providing the appropriate GFP |
| * flags are used. |
| * Return: The page on success or NULL if allocation fails. |
| */ |
| struct page *alloc_pages(gfp_t gfp, unsigned int order) |
| { |
| struct mempolicy *pol = &default_policy; |
| |
| /* |
| * No reference counting needed for current->mempolicy |
| * nor system default_policy |
| */ |
| if (!in_interrupt() && !(gfp & __GFP_THISNODE)) |
| pol = get_task_policy(current); |
| |
| return alloc_pages_mpol(gfp, order, |
| pol, NO_INTERLEAVE_INDEX, numa_node_id()); |
| } |
| EXPORT_SYMBOL(alloc_pages); |
| |
| struct folio *folio_alloc(gfp_t gfp, unsigned int order) |
| { |
| return page_rmappable_folio(alloc_pages(gfp | __GFP_COMP, order)); |
| } |
| EXPORT_SYMBOL(folio_alloc); |
| |
| static unsigned long alloc_pages_bulk_array_interleave(gfp_t gfp, |
| struct mempolicy *pol, unsigned long nr_pages, |
| struct page **page_array) |
| { |
| int nodes; |
| unsigned long nr_pages_per_node; |
| int delta; |
| int i; |
| unsigned long nr_allocated; |
| unsigned long total_allocated = 0; |
| |
| nodes = nodes_weight(pol->nodes); |
| nr_pages_per_node = nr_pages / nodes; |
| delta = nr_pages - nodes * nr_pages_per_node; |
| |
| for (i = 0; i < nodes; i++) { |
| if (delta) { |
| nr_allocated = __alloc_pages_bulk(gfp, |
| interleave_nodes(pol), NULL, |
| nr_pages_per_node + 1, NULL, |
| page_array); |
| delta--; |
| } else { |
| nr_allocated = __alloc_pages_bulk(gfp, |
| interleave_nodes(pol), NULL, |
| nr_pages_per_node, NULL, page_array); |
| } |
| |
| page_array += nr_allocated; |
| total_allocated += nr_allocated; |
| } |
| |
| return total_allocated; |
| } |
| |
| static unsigned long alloc_pages_bulk_array_weighted_interleave(gfp_t gfp, |
| struct mempolicy *pol, unsigned long nr_pages, |
| struct page **page_array) |
| { |
| struct task_struct *me = current; |
| unsigned int cpuset_mems_cookie; |
| unsigned long total_allocated = 0; |
| unsigned long nr_allocated = 0; |
| unsigned long rounds; |
| unsigned long node_pages, delta; |
| u8 *table, *weights, weight; |
| unsigned int weight_total = 0; |
| unsigned long rem_pages = nr_pages; |
| nodemask_t nodes; |
| int nnodes, node; |
| int resume_node = MAX_NUMNODES - 1; |
| u8 resume_weight = 0; |
| int prev_node; |
| int i; |
| |
| if (!nr_pages) |
| return 0; |
| |
| /* read the nodes onto the stack, retry if done during rebind */ |
| do { |
| cpuset_mems_cookie = read_mems_allowed_begin(); |
| nnodes = read_once_policy_nodemask(pol, &nodes); |
| } while (read_mems_allowed_retry(cpuset_mems_cookie)); |
| |
| /* if the nodemask has become invalid, we cannot do anything */ |
| if (!nnodes) |
| return 0; |
| |
| /* Continue allocating from most recent node and adjust the nr_pages */ |
| node = me->il_prev; |
| weight = me->il_weight; |
| if (weight && node_isset(node, nodes)) { |
| node_pages = min(rem_pages, weight); |
| nr_allocated = __alloc_pages_bulk(gfp, node, NULL, node_pages, |
| NULL, page_array); |
| page_array += nr_allocated; |
| total_allocated += nr_allocated; |
| /* if that's all the pages, no need to interleave */ |
| if (rem_pages <= weight) { |
| me->il_weight -= rem_pages; |
| return total_allocated; |
| } |
| /* Otherwise we adjust remaining pages, continue from there */ |
| rem_pages -= weight; |
| } |
| /* clear active weight in case of an allocation failure */ |
| me->il_weight = 0; |
| prev_node = node; |
| |
| /* create a local copy of node weights to operate on outside rcu */ |
| weights = kzalloc(nr_node_ids, GFP_KERNEL); |
| if (!weights) |
| return total_allocated; |
| |
| rcu_read_lock(); |
| table = rcu_dereference(iw_table); |
| if (table) |
| memcpy(weights, table, nr_node_ids); |
| rcu_read_unlock(); |
| |
| /* calculate total, detect system default usage */ |
| for_each_node_mask(node, nodes) { |
| if (!weights[node]) |
| weights[node] = 1; |
| weight_total += weights[node]; |
| } |
| |
| /* |
| * Calculate rounds/partial rounds to minimize __alloc_pages_bulk calls. |
| * Track which node weighted interleave should resume from. |
| * |
| * if (rounds > 0) and (delta == 0), resume_node will always be |
| * the node following prev_node and its weight. |
| */ |
| rounds = rem_pages / weight_total; |
| delta = rem_pages % weight_total; |
| resume_node = next_node_in(prev_node, nodes); |
| resume_weight = weights[resume_node]; |
| for (i = 0; i < nnodes; i++) { |
| node = next_node_in(prev_node, nodes); |
| weight = weights[node]; |
| node_pages = weight * rounds; |
| /* If a delta exists, add this node's portion of the delta */ |
| if (delta > weight) { |
| node_pages += weight; |
| delta -= weight; |
| } else if (delta) { |
| /* when delta is depleted, resume from that node */ |
| node_pages += delta; |
| resume_node = node; |
| resume_weight = weight - delta; |
| delta = 0; |
| } |
| /* node_pages can be 0 if an allocation fails and rounds == 0 */ |
| if (!node_pages) |
| break; |
| nr_allocated = __alloc_pages_bulk(gfp, node, NULL, node_pages, |
| NULL, page_array); |
| page_array += nr_allocated; |
| total_allocated += nr_allocated; |
| if (total_allocated == nr_pages) |
| break; |
| prev_node = node; |
| } |
| me->il_prev = resume_node; |
| me->il_weight = resume_weight; |
| kfree(weights); |
| return total_allocated; |
| } |
| |
| static unsigned long alloc_pages_bulk_array_preferred_many(gfp_t gfp, int nid, |
| struct mempolicy *pol, unsigned long nr_pages, |
| struct page **page_array) |
| { |
| gfp_t preferred_gfp; |
| unsigned long nr_allocated = 0; |
| |
| preferred_gfp = gfp | __GFP_NOWARN; |
| preferred_gfp &= ~(__GFP_DIRECT_RECLAIM | __GFP_NOFAIL); |
| |
| nr_allocated = __alloc_pages_bulk(preferred_gfp, nid, &pol->nodes, |
| nr_pages, NULL, page_array); |
| |
| if (nr_allocated < nr_pages) |
| nr_allocated += __alloc_pages_bulk(gfp, numa_node_id(), NULL, |
| nr_pages - nr_allocated, NULL, |
| page_array + nr_allocated); |
| return nr_allocated; |
| } |
| |
| /* alloc pages bulk and mempolicy should be considered at the |
| * same time in some situation such as vmalloc. |
| * |
| * It can accelerate memory allocation especially interleaving |
| * allocate memory. |
| */ |
| unsigned long alloc_pages_bulk_array_mempolicy(gfp_t gfp, |
| unsigned long nr_pages, struct page **page_array) |
| { |
| struct mempolicy *pol = &default_policy; |
| nodemask_t *nodemask; |
| int nid; |
| |
| if (!in_interrupt() && !(gfp & __GFP_THISNODE)) |
| pol = get_task_policy(current); |
| |
| if (pol->mode == MPOL_INTERLEAVE) |
| return alloc_pages_bulk_array_interleave(gfp, pol, |
| nr_pages, page_array); |
| |
| if (pol->mode == MPOL_WEIGHTED_INTERLEAVE) |
| return alloc_pages_bulk_array_weighted_interleave( |
| gfp, pol, nr_pages, page_array); |
| |
| if (pol->mode == MPOL_PREFERRED_MANY) |
| return alloc_pages_bulk_array_preferred_many(gfp, |
| numa_node_id(), pol, nr_pages, page_array); |
| |
| nid = numa_node_id(); |
| nodemask = policy_nodemask(gfp, pol, NO_INTERLEAVE_INDEX, &nid); |
| return __alloc_pages_bulk(gfp, nid, nodemask, |
| nr_pages, NULL, page_array); |
| } |
| |
| int vma_dup_policy(struct vm_area_struct *src, struct vm_area_struct *dst) |
| { |
| struct mempolicy *pol = mpol_dup(src->vm_policy); |
| |
| if (IS_ERR(pol)) |
| return PTR_ERR(pol); |
| dst->vm_policy = pol; |
| return 0; |
| } |
| |
| /* |
| * If mpol_dup() sees current->cpuset == cpuset_being_rebound, then it |
| * rebinds the mempolicy its copying by calling mpol_rebind_policy() |
| * with the mems_allowed returned by cpuset_mems_allowed(). This |
| * keeps mempolicies cpuset relative after its cpuset moves. See |
| * further kernel/cpuset.c update_nodemask(). |
| * |
| * current's mempolicy may be rebinded by the other task(the task that changes |
| * cpuset's mems), so we needn't do rebind work for current task. |
| */ |
| |
| /* Slow path of a mempolicy duplicate */ |
| struct mempolicy *__mpol_dup(struct mempolicy *old) |
| { |
| struct mempolicy *new = kmem_cache_alloc(policy_cache, GFP_KERNEL); |
| |
| if (!new) |
| return ERR_PTR(-ENOMEM); |
| |
| /* task's mempolicy is protected by alloc_lock */ |
| if (old == current->mempolicy) { |
| task_lock(current); |
| *new = *old; |
| task_unlock(current); |
| } else |
| *new = *old; |
| |
| if (current_cpuset_is_being_rebound()) { |
| nodemask_t mems = cpuset_mems_allowed(current); |
| mpol_rebind_policy(new, &mems); |
| } |
| atomic_set(&new->refcnt, 1); |
| return new; |
| } |
| |
| /* Slow path of a mempolicy comparison */ |
| bool __mpol_equal(struct mempolicy *a, struct mempolicy *b) |
| { |
| if (!a || !b) |
| return false; |
| if (a->mode != b->mode) |
| return false; |
| if (a->flags != b->flags) |
| return false; |
| if (a->home_node != b->home_node) |
| return false; |
| if (mpol_store_user_nodemask(a)) |
| if (!nodes_equal(a->w.user_nodemask, b->w.user_nodemask)) |
| return false; |
| |
| switch (a->mode) { |
| case MPOL_BIND: |
| case MPOL_INTERLEAVE: |
| case MPOL_PREFERRED: |
| case MPOL_PREFERRED_MANY: |
| case MPOL_WEIGHTED_INTERLEAVE: |
| return !!nodes_equal(a->nodes, b->nodes); |
| case MPOL_LOCAL: |
| return true; |
| default: |
| BUG(); |
| return false; |
| } |
| } |
| |
| /* |
| * Shared memory backing store policy support. |
| * |
| * Remember policies even when nobody has shared memory mapped. |
| * The policies are kept in Red-Black tree linked from the inode. |
| * They are protected by the sp->lock rwlock, which should be held |
| * for any accesses to the tree. |
| */ |
| |
| /* |
| * lookup first element intersecting start-end. Caller holds sp->lock for |
| * reading or for writing |
| */ |
| static struct sp_node *sp_lookup(struct shared_policy *sp, |
| pgoff_t start, pgoff_t end) |
| { |
| struct rb_node *n = sp->root.rb_node; |
| |
| while (n) { |
| struct sp_node *p = rb_entry(n, struct sp_node, nd); |
| |
| if (start >= p->end) |
| n = n->rb_right; |
| else if (end <= p->start) |
| n = n->rb_left; |
| else |
| break; |
| } |
| if (!n) |
| return NULL; |
| for (;;) { |
| struct sp_node *w = NULL; |
| struct rb_node *prev = rb_prev(n); |
| if (!prev) |
| break; |
| w = rb_entry(prev, struct sp_node, nd); |
| if (w->end <= start) |
| break; |
| n = prev; |
| } |
| return rb_entry(n, struct sp_node, nd); |
| } |
| |
| /* |
| * Insert a new shared policy into the list. Caller holds sp->lock for |
| * writing. |
| */ |
| static void sp_insert(struct shared_policy *sp, struct sp_node *new) |
| { |
| struct rb_node **p = &sp->root.rb_node; |
| struct rb_node *parent = NULL; |
| struct sp_node *nd; |
| |
| while (*p) { |
| parent = *p; |
| nd = rb_entry(parent, struct sp_node, nd); |
| if (new->start < nd->start) |
| p = &(*p)->rb_left; |
| else if (new->end > nd->end) |
| p = &(*p)->rb_right; |
| else |
| BUG(); |
| } |
| rb_link_node(&new->nd, parent, p); |
| rb_insert_color(&new->nd, &sp->root); |
| } |
| |
| /* Find shared policy intersecting idx */ |
| struct mempolicy *mpol_shared_policy_lookup(struct shared_policy *sp, |
| pgoff_t idx) |
| { |
| struct mempolicy *pol = NULL; |
| struct sp_node *sn; |
| |
| if (!sp->root.rb_node) |
| return NULL; |
| read_lock(&sp->lock); |
| sn = sp_lookup(sp, idx, idx+1); |
| if (sn) { |
| mpol_get(sn->policy); |
| pol = sn->policy; |
| } |
| read_unlock(&sp->lock); |
| return pol; |
| } |
| |
| static void sp_free(struct sp_node *n) |
| { |
| mpol_put(n->policy); |
| kmem_cache_free(sn_cache, n); |
| } |
| |
| /** |
| * mpol_misplaced - check whether current folio node is valid in policy |
| * |
| * @folio: folio to be checked |
| * @vma: vm area where folio mapped |
| * @addr: virtual address in @vma for shared policy lookup and interleave policy |
| * |
| * Lookup current policy node id for vma,addr and "compare to" folio's |
| * node id. Policy determination "mimics" alloc_page_vma(). |
| * Called from fault path where we know the vma and faulting address. |
| * |
| * Return: NUMA_NO_NODE if the page is in a node that is valid for this |
| * policy, or a suitable node ID to allocate a replacement folio from. |
| */ |
| int mpol_misplaced(struct folio *folio, struct vm_area_struct *vma, |
| unsigned long addr) |
| { |
| struct mempolicy *pol; |
| pgoff_t ilx; |
| struct zoneref *z; |
| int curnid = folio_nid(folio); |
| int thiscpu = raw_smp_processor_id(); |
| int thisnid = cpu_to_node(thiscpu); |
| int polnid = NUMA_NO_NODE; |
| int ret = NUMA_NO_NODE; |
| |
| pol = get_vma_policy(vma, addr, folio_order(folio), &ilx); |
| if (!(pol->flags & MPOL_F_MOF)) |
| goto out; |
| |
| switch (pol->mode) { |
| case MPOL_INTERLEAVE: |
| polnid = interleave_nid(pol, ilx); |
| break; |
| |
| case MPOL_WEIGHTED_INTERLEAVE: |
| polnid = weighted_interleave_nid(pol, ilx); |
| break; |
| |
| case MPOL_PREFERRED: |
| if (node_isset(curnid, pol->nodes)) |
| goto out; |
| polnid = first_node(pol->nodes); |
| break; |
| |
| case MPOL_LOCAL: |
| polnid = numa_node_id(); |
| break; |
| |
| case MPOL_BIND: |
| /* Optimize placement among multiple nodes via NUMA balancing */ |
| if (pol->flags & MPOL_F_MORON) { |
| if (node_isset(thisnid, pol->nodes)) |
| break; |
| goto out; |
| } |
| fallthrough; |
| |
| case MPOL_PREFERRED_MANY: |
| /* |
| * use current page if in policy nodemask, |
| * else select nearest allowed node, if any. |
| * If no allowed nodes, use current [!misplaced]. |
| */ |
| if (node_isset(curnid, pol->nodes)) |
| goto out; |
| z = first_zones_zonelist( |
| node_zonelist(numa_node_id(), GFP_HIGHUSER), |
| gfp_zone(GFP_HIGHUSER), |
| &pol->nodes); |
| polnid = zone_to_nid(z->zone); |
| break; |
| |
| default: |
| BUG(); |
| } |
| |
| /* Migrate the folio towards the node whose CPU is referencing it */ |
| if (pol->flags & MPOL_F_MORON) { |
| polnid = thisnid; |
| |
| if (!should_numa_migrate_memory(current, folio, curnid, |
| thiscpu)) |
| goto out; |
| } |
| |
| if (curnid != polnid) |
| ret = polnid; |
| out: |
| mpol_cond_put(pol); |
| |
| return ret; |
| } |
| |
| /* |
| * Drop the (possibly final) reference to task->mempolicy. It needs to be |
| * dropped after task->mempolicy is set to NULL so that any allocation done as |
| * part of its kmem_cache_free(), such as by KASAN, doesn't reference a freed |
| * policy. |
| */ |
| void mpol_put_task_policy(struct task_struct *task) |
| { |
| struct mempolicy *pol; |
| |
| task_lock(task); |
| pol = task->mempolicy; |
| task->mempolicy = NULL; |
| task_unlock(task); |
| mpol_put(pol); |
| } |
| |
| static void sp_delete(struct shared_policy *sp, struct sp_node *n) |
| { |
| rb_erase(&n->nd, &sp->root); |
| sp_free(n); |
| } |
| |
| static void sp_node_init(struct sp_node *node, unsigned long start, |
| unsigned long end, struct mempolicy *pol) |
| { |
| node->start = start; |
| node->end = end; |
| node->policy = pol; |
| } |
| |
| static struct sp_node *sp_alloc(unsigned long start, unsigned long end, |
| struct mempolicy *pol) |
| { |
| struct sp_node *n; |
| struct mempolicy *newpol; |
| |
| n = kmem_cache_alloc(sn_cache, GFP_KERNEL); |
| if (!n) |
| return NULL; |
| |
| newpol = mpol_dup(pol); |
| if (IS_ERR(newpol)) { |
| kmem_cache_free(sn_cache, n); |
| return NULL; |
| } |
| newpol->flags |= MPOL_F_SHARED; |
| sp_node_init(n, start, end, newpol); |
| |
| return n; |
| } |
| |
| /* Replace a policy range. */ |
| static int shared_policy_replace(struct shared_policy *sp, pgoff_t start, |
| pgoff_t end, struct sp_node *new) |
| { |
| struct sp_node *n; |
| struct sp_node *n_new = NULL; |
| struct mempolicy *mpol_new = NULL; |
| int ret = 0; |
| |
| restart: |
| write_lock(&sp->lock); |
| n = sp_lookup(sp, start, end); |
| /* Take care of old policies in the same range. */ |
| while (n && n->start < end) { |
| struct rb_node *next = rb_next(&n->nd); |
| if (n->start >= start) { |
| if (n->end <= end) |
| sp_delete(sp, n); |
| else |
| n->start = end; |
| } else { |
| /* Old policy spanning whole new range. */ |
| if (n->end > end) { |
| if (!n_new) |
| goto alloc_new; |
| |
| *mpol_new = *n->policy; |
| atomic_set(&mpol_new->refcnt, 1); |
| sp_node_init(n_new, end, n->end, mpol_new); |
| n->end = start; |
| sp_insert(sp, n_new); |
| n_new = NULL; |
| mpol_new = NULL; |
| break; |
| } else |
| n->end = start; |
| } |
| if (!next) |
| break; |
| n = rb_entry(next, struct sp_node, nd); |
| } |
| if (new) |
| sp_insert(sp, new); |
| write_unlock(&sp->lock); |
| ret = 0; |
| |
| err_out: |
| if (mpol_new) |
| mpol_put(mpol_new); |
| if (n_new) |
| kmem_cache_free(sn_cache, n_new); |
| |
| return ret; |
| |
| alloc_new: |
| write_unlock(&sp->lock); |
| ret = -ENOMEM; |
| n_new = kmem_cache_alloc(sn_cache, GFP_KERNEL); |
| if (!n_new) |
| goto err_out; |
| mpol_new = kmem_cache_alloc(policy_cache, GFP_KERNEL); |
| if (!mpol_new) |
| goto err_out; |
| atomic_set(&mpol_new->refcnt, 1); |
| goto restart; |
| } |
| |
| /** |
| * mpol_shared_policy_init - initialize shared policy for inode |
| * @sp: pointer to inode shared policy |
| * @mpol: struct mempolicy to install |
| * |
| * 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) |
| { |
| int ret; |
| |
| sp->root = RB_ROOT; /* empty tree == default mempolicy */ |
| rwlock_init(&sp->lock); |
| |
| if (mpol) { |
| struct sp_node *sn; |
| struct mempolicy *npol; |
| NODEMASK_SCRATCH(scratch); |
| |
| if (!scratch) |
| goto put_mpol; |
| |
| /* contextualize the tmpfs mount point mempolicy to this file */ |
| npol = mpol_new(mpol->mode, mpol->flags, &mpol->w.user_nodemask); |
| if (IS_ERR(npol)) |
| goto free_scratch; /* no valid nodemask intersection */ |
| |
| task_lock(current); |
| ret = mpol_set_nodemask(npol, &mpol->w.user_nodemask, scratch); |
| task_unlock(current); |
| if (ret) |
| goto put_npol; |
| |
| /* alloc node covering entire file; adds ref to file's npol */ |
| sn = sp_alloc(0, MAX_LFS_FILESIZE >> PAGE_SHIFT, npol); |
| if (sn) |
| sp_insert(sp, sn); |
| put_npol: |
| mpol_put(npol); /* drop initial ref on file's npol */ |
| free_scratch: |
| NODEMASK_SCRATCH_FREE(scratch); |
| put_mpol: |
| mpol_put(mpol); /* drop our incoming ref on sb mpol */ |
| } |
| } |
| |
| int mpol_set_shared_policy(struct shared_policy *sp, |
| struct vm_area_struct *vma, struct mempolicy *pol) |
| { |
| int err; |
| struct sp_node *new = NULL; |
| unsigned long sz = vma_pages(vma); |
| |
| if (pol) { |
| new = sp_alloc(vma->vm_pgoff, vma->vm_pgoff + sz, pol); |
| if (!new) |
| return -ENOMEM; |
| } |
| err = shared_policy_replace(sp, vma->vm_pgoff, vma->vm_pgoff + sz, new); |
| if (err && new) |
| sp_free(new); |
| return err; |
| } |
| |
| /* Free a backing policy store on inode delete. */ |
| void mpol_free_shared_policy(struct shared_policy *sp) |
| { |
| struct sp_node *n; |
| struct rb_node *next; |
| |
| if (!sp->root.rb_node) |
| return; |
| write_lock(&sp->lock); |
| next = rb_first(&sp->root); |
| while (next) { |
| n = rb_entry(next, struct sp_node, nd); |
| next = rb_next(&n->nd); |
| sp_delete(sp, n); |
| } |
| write_unlock(&sp->lock); |
| } |
| |
| #ifdef CONFIG_NUMA_BALANCING |
| static int __initdata numabalancing_override; |
| |
| static void __init check_numabalancing_enable(void) |
| { |
| bool numabalancing_default = false; |
| |
| if (IS_ENABLED(CONFIG_NUMA_BALANCING_DEFAULT_ENABLED)) |
| numabalancing_default = true; |
| |
| /* Parsed by setup_numabalancing. override == 1 enables, -1 disables */ |
| if (numabalancing_override) |
| set_numabalancing_state(numabalancing_override == 1); |
| |
| if (num_online_nodes() > 1 && !numabalancing_override) { |
| pr_info("%s automatic NUMA balancing. Configure with numa_balancing= or the kernel.numa_balancing sysctl\n", |
| numabalancing_default ? "Enabling" : "Disabling"); |
| set_numabalancing_state(numabalancing_default); |
| } |
| } |
| |
| static int __init setup_numabalancing(char *str) |
| { |
| int ret = 0; |
| if (!str) |
| goto out; |
| |
| if (!strcmp(str, "enable")) { |
| numabalancing_override = 1; |
| ret = 1; |
| } else if (!strcmp(str, "disable")) { |
| numabalancing_override = -1; |
| ret = 1; |
| } |
| out: |
| if (!ret) |
| pr_warn("Unable to parse numa_balancing=\n"); |
| |
| return ret; |
| } |
| __setup("numa_balancing=", setup_numabalancing); |
| #else |
| static inline void __init check_numabalancing_enable(void) |
| { |
| } |
| #endif /* CONFIG_NUMA_BALANCING */ |
| |
| void __init numa_policy_init(void) |
| { |
| nodemask_t interleave_nodes; |
| unsigned long largest = 0; |
| int nid, prefer = 0; |
| |
| policy_cache = kmem_cache_create("numa_policy", |
| sizeof(struct mempolicy), |
| 0, SLAB_PANIC, NULL); |
| |
| sn_cache = kmem_cache_create("shared_policy_node", |
| sizeof(struct sp_node), |
| 0, SLAB_PANIC, NULL); |
| |
| for_each_node(nid) { |
| preferred_node_policy[nid] = (struct mempolicy) { |
| .refcnt = ATOMIC_INIT(1), |
| .mode = MPOL_PREFERRED, |
| .flags = MPOL_F_MOF | MPOL_F_MORON, |
| .nodes = nodemask_of_node(nid), |
| }; |
| } |
| |
| /* |
| * Set interleaving policy for system init. Interleaving is only |
| * enabled across suitably sized nodes (default is >= 16MB), or |
| * fall back to the largest node if they're all smaller. |
| */ |
| nodes_clear(interleave_nodes); |
| for_each_node_state(nid, N_MEMORY) { |
| unsigned long total_pages = node_present_pages(nid); |
| |
| /* Preserve the largest node */ |
| if (largest < total_pages) { |
| largest = total_pages; |
| prefer = nid; |
| } |
| |
| /* Interleave this node? */ |
| if ((total_pages << PAGE_SHIFT) >= (16 << 20)) |
| node_set(nid, interleave_nodes); |
| } |
| |
| /* All too small, use the largest */ |
| if (unlikely(nodes_empty(interleave_nodes))) |
| node_set(prefer, interleave_nodes); |
| |
| if (do_set_mempolicy(MPOL_INTERLEAVE, 0, &interleave_nodes)) |
| pr_err("%s: interleaving failed\n", __func__); |
| |
| check_numabalancing_enable(); |
| } |
| |
| /* Reset policy of current process to default */ |
| void numa_default_policy(void) |
| { |
| do_set_mempolicy(MPOL_DEFAULT, 0, NULL); |
| } |
| |
| /* |
| * Parse and format mempolicy from/to strings |
| */ |
| static const char * const policy_modes[] = |
| { |
| [MPOL_DEFAULT] = "default", |
| [MPOL_PREFERRED] = "prefer", |
| [MPOL_BIND] = "bind", |
| [MPOL_INTERLEAVE] = "interleave", |
| [MPOL_WEIGHTED_INTERLEAVE] = "weighted interleave", |
| [MPOL_LOCAL] = "local", |
| [MPOL_PREFERRED_MANY] = "prefer (many)", |
| }; |
| |
| #ifdef CONFIG_TMPFS |
| /** |
| * mpol_parse_str - parse string to mempolicy, for tmpfs mpol mount option. |
| * @str: string containing mempolicy to parse |
| * @mpol: pointer to struct mempolicy pointer, returned on success. |
| * |
| * Format of input: |
| * <mode>[=<flags>][:<nodelist>] |
| * |
| * Return: %0 on success, else %1 |
| */ |
| int mpol_parse_str(char *str, struct mempolicy **mpol) |
| { |
| struct mempolicy *new = NULL; |
| unsigned short mode_flags; |
| nodemask_t nodes; |
| char *nodelist = strchr(str, ':'); |
| char *flags = strchr(str, '='); |
| int err = 1, mode; |
| |
| if (flags) |
| *flags++ = '\0'; /* terminate mode string */ |
| |
| if (nodelist) { |
| /* NUL-terminate mode or flags string */ |
| *nodelist++ = '\0'; |
| if (nodelist_parse(nodelist, nodes)) |
| goto out; |
| if (!nodes_subset(nodes, node_states[N_MEMORY])) |
| goto out; |
| } else |
| nodes_clear(nodes); |
| |
| mode = match_string(policy_modes, MPOL_MAX, str); |
| if (mode < 0) |
| goto out; |
| |
| switch (mode) { |
| case MPOL_PREFERRED: |
| /* |
| * Insist on a nodelist of one node only, although later |
| * we use first_node(nodes) to grab a single node, so here |
| * nodelist (or nodes) cannot be empty. |
| */ |
| if (nodelist |