/*- * Copyright (c)2006,2007,2008,2009 YAMAMOTO Takashi, * Copyright (c) 2013 EMC Corp. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * From: * $NetBSD: vmem_impl.h,v 1.2 2013/01/29 21:26:24 para Exp $ * $NetBSD: subr_vmem.c,v 1.83 2013/03/06 11:20:10 yamt Exp $ */ /* * reference: * - Magazines and Vmem: Extending the Slab Allocator * to Many CPUs and Arbitrary Resources * http://www.usenix.org/event/usenix01/bonwick.html */ #include __FBSDID("$FreeBSD$"); #include "opt_ddb.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include "opt_vm.h" #include #include #include #include #include #include #include #include #include #define VMEM_MAXORDER (sizeof(vmem_size_t) * NBBY) #define VMEM_HASHSIZE_MIN 16 #define VMEM_HASHSIZE_MAX 131072 #define VMEM_QCACHE_IDX_MAX 16 #define VMEM_FITMASK (M_BESTFIT | M_FIRSTFIT) #define VMEM_FLAGS \ (M_NOWAIT | M_WAITOK | M_USE_RESERVE | M_NOVM | M_BESTFIT | M_FIRSTFIT) #define BT_FLAGS (M_NOWAIT | M_WAITOK | M_USE_RESERVE | M_NOVM) #define QC_NAME_MAX 16 /* * Data structures private to vmem. */ MALLOC_DEFINE(M_VMEM, "vmem", "vmem internal structures"); typedef struct vmem_btag bt_t; TAILQ_HEAD(vmem_seglist, vmem_btag); LIST_HEAD(vmem_freelist, vmem_btag); LIST_HEAD(vmem_hashlist, vmem_btag); struct qcache { uma_zone_t qc_cache; vmem_t *qc_vmem; vmem_size_t qc_size; char qc_name[QC_NAME_MAX]; }; typedef struct qcache qcache_t; #define QC_POOL_TO_QCACHE(pool) ((qcache_t *)(pool->pr_qcache)) #define VMEM_NAME_MAX 16 /* vmem arena */ struct vmem { struct mtx_padalign vm_lock; struct cv vm_cv; char vm_name[VMEM_NAME_MAX+1]; LIST_ENTRY(vmem) vm_alllist; struct vmem_hashlist vm_hash0[VMEM_HASHSIZE_MIN]; struct vmem_freelist vm_freelist[VMEM_MAXORDER]; struct vmem_seglist vm_seglist; struct vmem_hashlist *vm_hashlist; vmem_size_t vm_hashsize; /* Constant after init */ vmem_size_t vm_qcache_max; vmem_size_t vm_quantum_mask; vmem_size_t vm_import_quantum; int vm_quantum_shift; /* Written on alloc/free */ LIST_HEAD(, vmem_btag) vm_freetags; int vm_nfreetags; int vm_nbusytag; vmem_size_t vm_inuse; vmem_size_t vm_size; /* Used on import. */ vmem_import_t *vm_importfn; vmem_release_t *vm_releasefn; void *vm_arg; /* Space exhaustion callback. */ vmem_reclaim_t *vm_reclaimfn; /* quantum cache */ qcache_t vm_qcache[VMEM_QCACHE_IDX_MAX]; }; /* boundary tag */ struct vmem_btag { TAILQ_ENTRY(vmem_btag) bt_seglist; union { LIST_ENTRY(vmem_btag) u_freelist; /* BT_TYPE_FREE */ LIST_ENTRY(vmem_btag) u_hashlist; /* BT_TYPE_BUSY */ } bt_u; #define bt_hashlist bt_u.u_hashlist #define bt_freelist bt_u.u_freelist vmem_addr_t bt_start; vmem_size_t bt_size; int bt_type; }; #define BT_TYPE_SPAN 1 /* Allocated from importfn */ #define BT_TYPE_SPAN_STATIC 2 /* vmem_add() or create. */ #define BT_TYPE_FREE 3 /* Available space. */ #define BT_TYPE_BUSY 4 /* Used space. */ #define BT_ISSPAN_P(bt) ((bt)->bt_type <= BT_TYPE_SPAN_STATIC) #define BT_END(bt) ((bt)->bt_start + (bt)->bt_size - 1) #if defined(DIAGNOSTIC) static void vmem_check(vmem_t *); #endif static struct callout vmem_periodic_ch; static int vmem_periodic_interval; static struct task vmem_periodic_wk; static struct mtx_padalign vmem_list_lock; static LIST_HEAD(, vmem) vmem_list = LIST_HEAD_INITIALIZER(vmem_list); /* ---- misc */ #define VMEM_CONDVAR_INIT(vm, wchan) cv_init(&vm->vm_cv, wchan) #define VMEM_CONDVAR_DESTROY(vm) cv_destroy(&vm->vm_cv) #define VMEM_CONDVAR_WAIT(vm) cv_wait(&vm->vm_cv, &vm->vm_lock) #define VMEM_CONDVAR_BROADCAST(vm) cv_broadcast(&vm->vm_cv) #define VMEM_LOCK(vm) mtx_lock(&vm->vm_lock) #define VMEM_TRYLOCK(vm) mtx_trylock(&vm->vm_lock) #define VMEM_UNLOCK(vm) mtx_unlock(&vm->vm_lock) #define VMEM_LOCK_INIT(vm, name) mtx_init(&vm->vm_lock, (name), NULL, MTX_DEF) #define VMEM_LOCK_DESTROY(vm) mtx_destroy(&vm->vm_lock) #define VMEM_ASSERT_LOCKED(vm) mtx_assert(&vm->vm_lock, MA_OWNED); #define VMEM_ALIGNUP(addr, align) (-(-(addr) & -(align))) #define VMEM_CROSS_P(addr1, addr2, boundary) \ ((((addr1) ^ (addr2)) & -(boundary)) != 0) #define ORDER2SIZE(order) ((vmem_size_t)1 << (order)) #define SIZE2ORDER(size) ((int)flsl(size) - 1) /* * Maximum number of boundary tags that may be required to satisfy an * allocation. Two may be required to import. Another two may be * required to clip edges. */ #define BT_MAXALLOC 4 /* * Max free limits the number of locally cached boundary tags. We * just want to avoid hitting the zone allocator for every call. */ #define BT_MAXFREE (BT_MAXALLOC * 8) /* Allocator for boundary tags. */ static uma_zone_t vmem_bt_zone; /* boot time arena storage. */ static struct vmem kernel_arena_storage; static struct vmem kmem_arena_storage; static struct vmem buffer_arena_storage; static struct vmem transient_arena_storage; vmem_t *kernel_arena = &kernel_arena_storage; vmem_t *kmem_arena = &kmem_arena_storage; vmem_t *buffer_arena = &buffer_arena_storage; vmem_t *transient_arena = &transient_arena_storage; #ifdef DEBUG_MEMGUARD static struct vmem memguard_arena_storage; vmem_t *memguard_arena = &memguard_arena_storage; #endif /* * Fill the vmem's boundary tag cache. We guarantee that boundary tag * allocation will not fail once bt_fill() passes. To do so we cache * at least the maximum possible tag allocations in the arena. */ static int bt_fill(vmem_t *vm, int flags) { bt_t *bt; VMEM_ASSERT_LOCKED(vm); /* * Only allow the kmem arena to dip into reserve tags. It is the * vmem where new tags come from. */ flags &= BT_FLAGS; if (vm != kmem_arena) flags &= ~M_USE_RESERVE; /* * Loop until we meet the reserve. To minimize the lock shuffle * and prevent simultaneous fills we first try a NOWAIT regardless * of the caller's flags. Specify M_NOVM so we don't recurse while * holding a vmem lock. */ while (vm->vm_nfreetags < BT_MAXALLOC) { bt = uma_zalloc(vmem_bt_zone, (flags & M_USE_RESERVE) | M_NOWAIT | M_NOVM); if (bt == NULL) { VMEM_UNLOCK(vm); bt = uma_zalloc(vmem_bt_zone, flags); VMEM_LOCK(vm); if (bt == NULL && (flags & M_NOWAIT) != 0) break; } LIST_INSERT_HEAD(&vm->vm_freetags, bt, bt_freelist); vm->vm_nfreetags++; } if (vm->vm_nfreetags < BT_MAXALLOC) return ENOMEM; return 0; } /* * Pop a tag off of the freetag stack. */ static bt_t * bt_alloc(vmem_t *vm) { bt_t *bt; VMEM_ASSERT_LOCKED(vm); bt = LIST_FIRST(&vm->vm_freetags); MPASS(bt != NULL); LIST_REMOVE(bt, bt_freelist); vm->vm_nfreetags--; return bt; } /* * Trim the per-vmem free list. Returns with the lock released to * avoid allocator recursions. */ static void bt_freetrim(vmem_t *vm, int freelimit) { LIST_HEAD(, vmem_btag) freetags; bt_t *bt; LIST_INIT(&freetags); VMEM_ASSERT_LOCKED(vm); while (vm->vm_nfreetags > freelimit) { bt = LIST_FIRST(&vm->vm_freetags); LIST_REMOVE(bt, bt_freelist); vm->vm_nfreetags--; LIST_INSERT_HEAD(&freetags, bt, bt_freelist); } VMEM_UNLOCK(vm); while ((bt = LIST_FIRST(&freetags)) != NULL) { LIST_REMOVE(bt, bt_freelist); uma_zfree(vmem_bt_zone, bt); } } static inline void bt_free(vmem_t *vm, bt_t *bt) { VMEM_ASSERT_LOCKED(vm); MPASS(LIST_FIRST(&vm->vm_freetags) != bt); LIST_INSERT_HEAD(&vm->vm_freetags, bt, bt_freelist); vm->vm_nfreetags++; } /* * freelist[0] ... [1, 1] * freelist[1] ... [2, 3] * freelist[2] ... [4, 7] * freelist[3] ... [8, 15] * : * freelist[n] ... [(1 << n), (1 << (n + 1)) - 1] * : */ static struct vmem_freelist * bt_freehead_tofree(vmem_t *vm, vmem_size_t size) { const vmem_size_t qsize = size >> vm->vm_quantum_shift; const int idx = SIZE2ORDER(qsize); MPASS(size != 0 && qsize != 0); MPASS((size & vm->vm_quantum_mask) == 0); MPASS(idx >= 0); MPASS(idx < VMEM_MAXORDER); return &vm->vm_freelist[idx]; } /* * bt_freehead_toalloc: return the freelist for the given size and allocation * strategy. * * For M_FIRSTFIT, return the list in which any blocks are large enough * for the requested size. otherwise, return the list which can have blocks * large enough for the requested size. */ static struct vmem_freelist * bt_freehead_toalloc(vmem_t *vm, vmem_size_t size, int strat) { const vmem_size_t qsize = size >> vm->vm_quantum_shift; int idx = SIZE2ORDER(qsize); MPASS(size != 0 && qsize != 0); MPASS((size & vm->vm_quantum_mask) == 0); if (strat == M_FIRSTFIT && ORDER2SIZE(idx) != qsize) { idx++; /* check too large request? */ } MPASS(idx >= 0); MPASS(idx < VMEM_MAXORDER); return &vm->vm_freelist[idx]; } /* ---- boundary tag hash */ static struct vmem_hashlist * bt_hashhead(vmem_t *vm, vmem_addr_t addr) { struct vmem_hashlist *list; unsigned int hash; hash = hash32_buf(&addr, sizeof(addr), 0); list = &vm->vm_hashlist[hash % vm->vm_hashsize]; return list; } static bt_t * bt_lookupbusy(vmem_t *vm, vmem_addr_t addr) { struct vmem_hashlist *list; bt_t *bt; VMEM_ASSERT_LOCKED(vm); list = bt_hashhead(vm, addr); LIST_FOREACH(bt, list, bt_hashlist) { if (bt->bt_start == addr) { break; } } return bt; } static void bt_rembusy(vmem_t *vm, bt_t *bt) { VMEM_ASSERT_LOCKED(vm); MPASS(vm->vm_nbusytag > 0); vm->vm_inuse -= bt->bt_size; vm->vm_nbusytag--; LIST_REMOVE(bt, bt_hashlist); } static void bt_insbusy(vmem_t *vm, bt_t *bt) { struct vmem_hashlist *list; VMEM_ASSERT_LOCKED(vm); MPASS(bt->bt_type == BT_TYPE_BUSY); list = bt_hashhead(vm, bt->bt_start); LIST_INSERT_HEAD(list, bt, bt_hashlist); vm->vm_nbusytag++; vm->vm_inuse += bt->bt_size; } /* ---- boundary tag list */ static void bt_remseg(vmem_t *vm, bt_t *bt) { TAILQ_REMOVE(&vm->vm_seglist, bt, bt_seglist); bt_free(vm, bt); } static void bt_insseg(vmem_t *vm, bt_t *bt, bt_t *prev) { TAILQ_INSERT_AFTER(&vm->vm_seglist, prev, bt, bt_seglist); } static void bt_insseg_tail(vmem_t *vm, bt_t *bt) { TAILQ_INSERT_TAIL(&vm->vm_seglist, bt, bt_seglist); } static void bt_remfree(vmem_t *vm, bt_t *bt) { MPASS(bt->bt_type == BT_TYPE_FREE); LIST_REMOVE(bt, bt_freelist); } static void bt_insfree(vmem_t *vm, bt_t *bt) { struct vmem_freelist *list; list = bt_freehead_tofree(vm, bt->bt_size); LIST_INSERT_HEAD(list, bt, bt_freelist); } /* ---- vmem internal functions */ /* * Import from the arena into the quantum cache in UMA. */ static int qc_import(void *arg, void **store, int cnt, int flags) { qcache_t *qc; vmem_addr_t addr; int i; qc = arg; flags |= M_BESTFIT; for (i = 0; i < cnt; i++) { if (vmem_xalloc(qc->qc_vmem, qc->qc_size, 0, 0, 0, VMEM_ADDR_MIN, VMEM_ADDR_MAX, flags, &addr) != 0) break; store[i] = (void *)addr; /* Only guarantee one allocation. */ flags &= ~M_WAITOK; flags |= M_NOWAIT; } return i; } /* * Release memory from the UMA cache to the arena. */ static void qc_release(void *arg, void **store, int cnt) { qcache_t *qc; int i; qc = arg; for (i = 0; i < cnt; i++) vmem_xfree(qc->qc_vmem, (vmem_addr_t)store[i], qc->qc_size); } static void qc_init(vmem_t *vm, vmem_size_t qcache_max) { qcache_t *qc; vmem_size_t size; int qcache_idx_max; int i; MPASS((qcache_max & vm->vm_quantum_mask) == 0); qcache_idx_max = MIN(qcache_max >> vm->vm_quantum_shift, VMEM_QCACHE_IDX_MAX); vm->vm_qcache_max = qcache_idx_max << vm->vm_quantum_shift; for (i = 0; i < qcache_idx_max; i++) { qc = &vm->vm_qcache[i]; size = (i + 1) << vm->vm_quantum_shift; snprintf(qc->qc_name, sizeof(qc->qc_name), "%s-%zu", vm->vm_name, size); qc->qc_vmem = vm; qc->qc_size = size; qc->qc_cache = uma_zcache_create(qc->qc_name, size, NULL, NULL, NULL, NULL, qc_import, qc_release, qc, UMA_ZONE_VM); MPASS(qc->qc_cache); } } static void qc_destroy(vmem_t *vm) { int qcache_idx_max; int i; qcache_idx_max = vm->vm_qcache_max >> vm->vm_quantum_shift; for (i = 0; i < qcache_idx_max; i++) uma_zdestroy(vm->vm_qcache[i].qc_cache); } static void qc_drain(vmem_t *vm) { int qcache_idx_max; int i; qcache_idx_max = vm->vm_qcache_max >> vm->vm_quantum_shift; for (i = 0; i < qcache_idx_max; i++) zone_drain(vm->vm_qcache[i].qc_cache); } #ifndef UMA_MD_SMALL_ALLOC static struct mtx_padalign vmem_bt_lock; /* * vmem_bt_alloc: Allocate a new page of boundary tags. * * On architectures with uma_small_alloc there is no recursion; no address * space need be allocated to allocate boundary tags. For the others, we * must handle recursion. Boundary tags are necessary to allocate new * boundary tags. * * UMA guarantees that enough tags are held in reserve to allocate a new * page of kva. We dip into this reserve by specifying M_USE_RESERVE only * when allocating the page to hold new boundary tags. In this way the * reserve is automatically filled by the allocation that uses the reserve. * * We still have to guarantee that the new tags are allocated atomically since * many threads may try concurrently. The bt_lock provides this guarantee. * We convert WAITOK allocations to NOWAIT and then handle the blocking here * on failure. It's ok to return NULL for a WAITOK allocation as UMA will * loop again after checking to see if we lost the race to allocate. * * There is a small race between vmem_bt_alloc() returning the page and the * zone lock being acquired to add the page to the zone. For WAITOK * allocations we just pause briefly. NOWAIT may experience a transient * failure. To alleviate this we permit a small number of simultaneous * fills to proceed concurrently so NOWAIT is less likely to fail unless * we are really out of KVA. */ static void * vmem_bt_alloc(uma_zone_t zone, int bytes, uint8_t *pflag, int wait) { vmem_addr_t addr; *pflag = UMA_SLAB_KMEM; /* * Single thread boundary tag allocation so that the address space * and memory are added in one atomic operation. */ mtx_lock(&vmem_bt_lock); if (vmem_xalloc(kmem_arena, bytes, 0, 0, 0, VMEM_ADDR_MIN, VMEM_ADDR_MAX, M_NOWAIT | M_NOVM | M_USE_RESERVE | M_BESTFIT, &addr) == 0) { if (kmem_back(kmem_object, addr, bytes, M_NOWAIT | M_USE_RESERVE) == 0) { mtx_unlock(&vmem_bt_lock); return ((void *)addr); } vmem_xfree(kmem_arena, addr, bytes); mtx_unlock(&vmem_bt_lock); /* * Out of memory, not address space. This may not even be * possible due to M_USE_RESERVE page allocation. */ if (wait & M_WAITOK) VM_WAIT; return (NULL); } mtx_unlock(&vmem_bt_lock); /* * We're either out of address space or lost a fill race. */ if (wait & M_WAITOK) pause("btalloc", 1); return (NULL); } #endif void vmem_startup(void) { mtx_init(&vmem_list_lock, "vmem list lock", NULL, MTX_DEF); vmem_bt_zone = uma_zcreate("vmem btag", sizeof(struct vmem_btag), NULL, NULL, NULL, NULL, UMA_ALIGN_PTR, UMA_ZONE_VM); #ifndef UMA_MD_SMALL_ALLOC mtx_init(&vmem_bt_lock, "btag lock", NULL, MTX_DEF); uma_prealloc(vmem_bt_zone, BT_MAXALLOC); /* * Reserve enough tags to allocate new tags. We allow multiple * CPUs to attempt to allocate new tags concurrently to limit * false restarts in UMA. */ uma_zone_reserve(vmem_bt_zone, BT_MAXALLOC * (mp_ncpus + 1) / 2); uma_zone_set_allocf(vmem_bt_zone, vmem_bt_alloc); #endif } /* ---- rehash */ static int vmem_rehash(vmem_t *vm, vmem_size_t newhashsize) { bt_t *bt; int i; struct vmem_hashlist *newhashlist; struct vmem_hashlist *oldhashlist; vmem_size_t oldhashsize; MPASS(newhashsize > 0); newhashlist = malloc(sizeof(struct vmem_hashlist) * newhashsize, M_VMEM, M_NOWAIT); if (newhashlist == NULL) return ENOMEM; for (i = 0; i < newhashsize; i++) { LIST_INIT(&newhashlist[i]); } VMEM_LOCK(vm); oldhashlist = vm->vm_hashlist; oldhashsize = vm->vm_hashsize; vm->vm_hashlist = newhashlist; vm->vm_hashsize = newhashsize; if (oldhashlist == NULL) { VMEM_UNLOCK(vm); return 0; } for (i = 0; i < oldhashsize; i++) { while ((bt = LIST_FIRST(&oldhashlist[i])) != NULL) { bt_rembusy(vm, bt); bt_insbusy(vm, bt); } } VMEM_UNLOCK(vm); if (oldhashlist != vm->vm_hash0) { free(oldhashlist, M_VMEM); } return 0; } static void vmem_periodic_kick(void *dummy) { taskqueue_enqueue(taskqueue_thread, &vmem_periodic_wk); } static void vmem_periodic(void *unused, int pending) { vmem_t *vm; vmem_size_t desired; vmem_size_t current; mtx_lock(&vmem_list_lock); LIST_FOREACH(vm, &vmem_list, vm_alllist) { #ifdef DIAGNOSTIC /* Convenient time to verify vmem state. */ VMEM_LOCK(vm); vmem_check(vm); VMEM_UNLOCK(vm); #endif desired = 1 << flsl(vm->vm_nbusytag); desired = MIN(MAX(desired, VMEM_HASHSIZE_MIN), VMEM_HASHSIZE_MAX); current = vm->vm_hashsize; /* Grow in powers of two. Shrink less aggressively. */ if (desired >= current * 2 || desired * 4 <= current) vmem_rehash(vm, desired); } mtx_unlock(&vmem_list_lock); callout_reset(&vmem_periodic_ch, vmem_periodic_interval, vmem_periodic_kick, NULL); } static void vmem_start_callout(void *unused) { TASK_INIT(&vmem_periodic_wk, 0, vmem_periodic, NULL); vmem_periodic_interval = hz * 10; callout_init(&vmem_periodic_ch, CALLOUT_MPSAFE); callout_reset(&vmem_periodic_ch, vmem_periodic_interval, vmem_periodic_kick, NULL); } SYSINIT(vfs, SI_SUB_CONFIGURE, SI_ORDER_ANY, vmem_start_callout, NULL); static void vmem_add1(vmem_t *vm, vmem_addr_t addr, vmem_size_t size, int type) { bt_t *btspan; bt_t *btfree; MPASS(type == BT_TYPE_SPAN || type == BT_TYPE_SPAN_STATIC); btspan = bt_alloc(vm); btspan->bt_type = type; btspan->bt_start = addr; btspan->bt_size = size; bt_insseg_tail(vm, btspan); btfree = bt_alloc(vm); btfree->bt_type = BT_TYPE_FREE; btfree->bt_start = addr; btfree->bt_size = size; bt_insseg(vm, btfree, btspan); bt_insfree(vm, btfree); vm->vm_size += size; } static void vmem_destroy1(vmem_t *vm) { bt_t *bt; /* * Drain per-cpu quantum caches. */ qc_destroy(vm); /* * The vmem should now only contain empty segments. */ VMEM_LOCK(vm); MPASS(vm->vm_nbusytag == 0); while ((bt = TAILQ_FIRST(&vm->vm_seglist)) != NULL) bt_remseg(vm, bt); if (vm->vm_hashlist != NULL && vm->vm_hashlist != vm->vm_hash0) free(vm->vm_hashlist, M_VMEM); bt_freetrim(vm, 0); VMEM_CONDVAR_DESTROY(vm); VMEM_LOCK_DESTROY(vm); free(vm, M_VMEM); } static int vmem_import(vmem_t *vm, vmem_size_t size, int flags) { vmem_addr_t addr; int error; if (vm->vm_importfn == NULL) return EINVAL; size = roundup(size, vm->vm_import_quantum); /* * Hide MAXALLOC tags so we're guaranteed to be able to add this * span and the tag we want to allocate from it. */ MPASS(vm->vm_nfreetags >= BT_MAXALLOC); vm->vm_nfreetags -= BT_MAXALLOC; VMEM_UNLOCK(vm); error = (vm->vm_importfn)(vm->vm_arg, size, flags, &addr); VMEM_LOCK(vm); vm->vm_nfreetags += BT_MAXALLOC; if (error) return ENOMEM; vmem_add1(vm, addr, size, BT_TYPE_SPAN); return 0; } /* * vmem_fit: check if a bt can satisfy the given restrictions. * * it's a caller's responsibility to ensure the region is big enough * before calling us. */ static int vmem_fit(const bt_t *bt, vmem_size_t size, vmem_size_t align, vmem_size_t phase, vmem_size_t nocross, vmem_addr_t minaddr, vmem_addr_t maxaddr, vmem_addr_t *addrp) { vmem_addr_t start; vmem_addr_t end; MPASS(size > 0); MPASS(bt->bt_size >= size); /* caller's responsibility */ /* * XXX assumption: vmem_addr_t and vmem_size_t are * unsigned integer of the same size. */ start = bt->bt_start; if (start < minaddr) { start = minaddr; } end = BT_END(bt); if (end > maxaddr) end = maxaddr; if (start > end) return (ENOMEM); start = VMEM_ALIGNUP(start - phase, align) + phase; if (start < bt->bt_start) start += align; if (VMEM_CROSS_P(start, start + size - 1, nocross)) { MPASS(align < nocross); start = VMEM_ALIGNUP(start - phase, nocross) + phase; } if (start <= end && end - start >= size - 1) { MPASS((start & (align - 1)) == phase); MPASS(!VMEM_CROSS_P(start, start + size - 1, nocross)); MPASS(minaddr <= start); MPASS(maxaddr == 0 || start + size - 1 <= maxaddr); MPASS(bt->bt_start <= start); MPASS(BT_END(bt) - start >= size - 1); *addrp = start; return (0); } return (ENOMEM); } /* * vmem_clip: Trim the boundary tag edges to the requested start and size. */ static void vmem_clip(vmem_t *vm, bt_t *bt, vmem_addr_t start, vmem_size_t size) { bt_t *btnew; bt_t *btprev; VMEM_ASSERT_LOCKED(vm); MPASS(bt->bt_type == BT_TYPE_FREE); MPASS(bt->bt_size >= size); bt_remfree(vm, bt); if (bt->bt_start != start) { btprev = bt_alloc(vm); btprev->bt_type = BT_TYPE_FREE; btprev->bt_start = bt->bt_start; btprev->bt_size = start - bt->bt_start; bt->bt_start = start; bt->bt_size -= btprev->bt_size; bt_insfree(vm, btprev); bt_insseg(vm, btprev, TAILQ_PREV(bt, vmem_seglist, bt_seglist)); } MPASS(bt->bt_start == start); if (bt->bt_size != size && bt->bt_size - size > vm->vm_quantum_mask) { /* split */ btnew = bt_alloc(vm); btnew->bt_type = BT_TYPE_BUSY; btnew->bt_start = bt->bt_start; btnew->bt_size = size; bt->bt_start = bt->bt_start + size; bt->bt_size -= size; bt_insfree(vm, bt); bt_insseg(vm, btnew, TAILQ_PREV(bt, vmem_seglist, bt_seglist)); bt_insbusy(vm, btnew); bt = btnew; } else { bt->bt_type = BT_TYPE_BUSY; bt_insbusy(vm, bt); } MPASS(bt->bt_size >= size); bt->bt_type = BT_TYPE_BUSY; } /* ---- vmem API */ void vmem_set_import(vmem_t *vm, vmem_import_t *importfn, vmem_release_t *releasefn, void *arg, vmem_size_t import_quantum) { VMEM_LOCK(vm); vm->vm_importfn = importfn; vm->vm_releasefn = releasefn; vm->vm_arg = arg; vm->vm_import_quantum = import_quantum; VMEM_UNLOCK(vm); } void vmem_set_reclaim(vmem_t *vm, vmem_reclaim_t *reclaimfn) { VMEM_LOCK(vm); vm->vm_reclaimfn = reclaimfn; VMEM_UNLOCK(vm); } /* * vmem_init: Initializes vmem arena. */ vmem_t * vmem_init(vmem_t *vm, const char *name, vmem_addr_t base, vmem_size_t size, vmem_size_t quantum, vmem_size_t qcache_max, int flags) { int i; MPASS(quantum > 0); bzero(vm, sizeof(*vm)); VMEM_CONDVAR_INIT(vm, name); VMEM_LOCK_INIT(vm, name); vm->vm_nfreetags = 0; LIST_INIT(&vm->vm_freetags); strlcpy(vm->vm_name, name, sizeof(vm->vm_name)); vm->vm_quantum_mask = quantum - 1; vm->vm_quantum_shift = SIZE2ORDER(quantum); MPASS(ORDER2SIZE(vm->vm_quantum_shift) == quantum); vm->vm_nbusytag = 0; vm->vm_size = 0; vm->vm_inuse = 0; qc_init(vm, qcache_max); TAILQ_INIT(&vm->vm_seglist); for (i = 0; i < VMEM_MAXORDER; i++) { LIST_INIT(&vm->vm_freelist[i]); } memset(&vm->vm_hash0, 0, sizeof(vm->vm_hash0)); vm->vm_hashsize = VMEM_HASHSIZE_MIN; vm->vm_hashlist = vm->vm_hash0; if (size != 0) { if (vmem_add(vm, base, size, flags) != 0) { vmem_destroy1(vm); return NULL; } } mtx_lock(&vmem_list_lock); LIST_INSERT_HEAD(&vmem_list, vm, vm_alllist); mtx_unlock(&vmem_list_lock); return vm; } /* * vmem_create: create an arena. */ vmem_t * vmem_create(const char *name, vmem_addr_t base, vmem_size_t size, vmem_size_t quantum, vmem_size_t qcache_max, int flags) { vmem_t *vm; vm = malloc(sizeof(*vm), M_VMEM, flags & (M_WAITOK|M_NOWAIT)); if (vm == NULL) return (NULL); if (vmem_init(vm, name, base, size, quantum, qcache_max, flags) == NULL) { free(vm, M_VMEM); return (NULL); } return (vm); } void vmem_destroy(vmem_t *vm) { mtx_lock(&vmem_list_lock); LIST_REMOVE(vm, vm_alllist); mtx_unlock(&vmem_list_lock); vmem_destroy1(vm); } vmem_size_t vmem_roundup_size(vmem_t *vm, vmem_size_t size) { return (size + vm->vm_quantum_mask) & ~vm->vm_quantum_mask; } /* * vmem_alloc: allocate resource from the arena. */ int vmem_alloc(vmem_t *vm, vmem_size_t size, int flags, vmem_addr_t *addrp) { const int strat __unused = flags & VMEM_FITMASK; qcache_t *qc; flags &= VMEM_FLAGS; MPASS(size > 0); MPASS(strat == M_BESTFIT || strat == M_FIRSTFIT); if ((flags & M_NOWAIT) == 0) WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "vmem_alloc"); if (size <= vm->vm_qcache_max) { qc = &vm->vm_qcache[(size - 1) >> vm->vm_quantum_shift]; *addrp = (vmem_addr_t)uma_zalloc(qc->qc_cache, flags); if (*addrp == 0) return (ENOMEM); return (0); } return vmem_xalloc(vm, size, 0, 0, 0, VMEM_ADDR_MIN, VMEM_ADDR_MAX, flags, addrp); } int vmem_xalloc(vmem_t *vm, const vmem_size_t size0, vmem_size_t align, const vmem_size_t phase, const vmem_size_t nocross, const vmem_addr_t minaddr, const vmem_addr_t maxaddr, int flags, vmem_addr_t *addrp) { const vmem_size_t size = vmem_roundup_size(vm, size0); struct vmem_freelist *list; struct vmem_freelist *first; struct vmem_freelist *end; vmem_size_t avail; bt_t *bt; int error; int strat; flags &= VMEM_FLAGS; strat = flags & VMEM_FITMASK; MPASS(size0 > 0); MPASS(size > 0); MPASS(strat == M_BESTFIT || strat == M_FIRSTFIT); MPASS((flags & (M_NOWAIT|M_WAITOK)) != (M_NOWAIT|M_WAITOK)); if ((flags & M_NOWAIT) == 0) WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK, NULL, "vmem_xalloc"); MPASS((align & vm->vm_quantum_mask) == 0); MPASS((align & (align - 1)) == 0); MPASS((phase & vm->vm_quantum_mask) == 0); MPASS((nocross & vm->vm_quantum_mask) == 0); MPASS((nocross & (nocross - 1)) == 0); MPASS((align == 0 && phase == 0) || phase < align); MPASS(nocross == 0 || nocross >= size); MPASS(minaddr <= maxaddr); MPASS(!VMEM_CROSS_P(phase, phase + size - 1, nocross)); if (align == 0) align = vm->vm_quantum_mask + 1; *addrp = 0; end = &vm->vm_freelist[VMEM_MAXORDER]; /* * choose a free block from which we allocate. */ first = bt_freehead_toalloc(vm, size, strat); VMEM_LOCK(vm); for (;;) { /* * Make sure we have enough tags to complete the * operation. */ if (vm->vm_nfreetags < BT_MAXALLOC && bt_fill(vm, flags) != 0) { error = ENOMEM; break; } /* * Scan freelists looking for a tag that satisfies the * allocation. If we're doing BESTFIT we may encounter * sizes below the request. If we're doing FIRSTFIT we * inspect only the first element from each list. */ for (list = first; list < end; list++) { LIST_FOREACH(bt, list, bt_freelist) { if (bt->bt_size >= size) { error = vmem_fit(bt, size, align, phase, nocross, minaddr, maxaddr, addrp); if (error == 0) { vmem_clip(vm, bt, *addrp, size); goto out; } } /* FIRST skips to the next list. */ if (strat == M_FIRSTFIT) break; } } /* * Retry if the fast algorithm failed. */ if (strat == M_FIRSTFIT) { strat = M_BESTFIT; first = bt_freehead_toalloc(vm, size, strat); continue; } /* * XXX it is possible to fail to meet restrictions with the * imported region. It is up to the user to specify the * import quantum such that it can satisfy any allocation. */ if (vmem_import(vm, size, flags) == 0) continue; /* * Try to free some space from the quantum cache or reclaim * functions if available. */ if (vm->vm_qcache_max != 0 || vm->vm_reclaimfn != NULL) { avail = vm->vm_size - vm->vm_inuse; VMEM_UNLOCK(vm); if (vm->vm_qcache_max != 0) qc_drain(vm); if (vm->vm_reclaimfn != NULL) vm->vm_reclaimfn(vm, flags); VMEM_LOCK(vm); /* If we were successful retry even NOWAIT. */ if (vm->vm_size - vm->vm_inuse > avail) continue; } if ((flags & M_NOWAIT) != 0) { error = ENOMEM; break; } VMEM_CONDVAR_WAIT(vm); } out: VMEM_UNLOCK(vm); if (error != 0 && (flags & M_NOWAIT) == 0) panic("failed to allocate waiting allocation\n"); return (error); } /* * vmem_free: free the resource to the arena. */ void vmem_free(vmem_t *vm, vmem_addr_t addr, vmem_size_t size) { qcache_t *qc; MPASS(size > 0); if (size <= vm->vm_qcache_max) { qc = &vm->vm_qcache[(size - 1) >> vm->vm_quantum_shift]; uma_zfree(qc->qc_cache, (void *)addr); } else vmem_xfree(vm, addr, size); } void vmem_xfree(vmem_t *vm, vmem_addr_t addr, vmem_size_t size) { bt_t *bt; bt_t *t; MPASS(size > 0); VMEM_LOCK(vm); bt = bt_lookupbusy(vm, addr); MPASS(bt != NULL); MPASS(bt->bt_start == addr); MPASS(bt->bt_size == vmem_roundup_size(vm, size) || bt->bt_size - vmem_roundup_size(vm, size) <= vm->vm_quantum_mask); MPASS(bt->bt_type == BT_TYPE_BUSY); bt_rembusy(vm, bt); bt->bt_type = BT_TYPE_FREE; /* coalesce */ t = TAILQ_NEXT(bt, bt_seglist); if (t != NULL && t->bt_type == BT_TYPE_FREE) { MPASS(BT_END(bt) < t->bt_start); /* YYY */ bt->bt_size += t->bt_size; bt_remfree(vm, t); bt_remseg(vm, t); } t = TAILQ_PREV(bt, vmem_seglist, bt_seglist); if (t != NULL && t->bt_type == BT_TYPE_FREE) { MPASS(BT_END(t) < bt->bt_start); /* YYY */ bt->bt_size += t->bt_size; bt->bt_start = t->bt_start; bt_remfree(vm, t); bt_remseg(vm, t); } t = TAILQ_PREV(bt, vmem_seglist, bt_seglist); MPASS(t != NULL); MPASS(BT_ISSPAN_P(t) || t->bt_type == BT_TYPE_BUSY); if (vm->vm_releasefn != NULL && t->bt_type == BT_TYPE_SPAN && t->bt_size == bt->bt_size) { vmem_addr_t spanaddr; vmem_size_t spansize; MPASS(t->bt_start == bt->bt_start); spanaddr = bt->bt_start; spansize = bt->bt_size; bt_remseg(vm, bt); bt_remseg(vm, t); vm->vm_size -= spansize; VMEM_CONDVAR_BROADCAST(vm); bt_freetrim(vm, BT_MAXFREE); (*vm->vm_releasefn)(vm->vm_arg, spanaddr, spansize); } else { bt_insfree(vm, bt); VMEM_CONDVAR_BROADCAST(vm); bt_freetrim(vm, BT_MAXFREE); } } /* * vmem_add: * */ int vmem_add(vmem_t *vm, vmem_addr_t addr, vmem_size_t size, int flags) { int error; error = 0; flags &= VMEM_FLAGS; VMEM_LOCK(vm); if (vm->vm_nfreetags >= BT_MAXALLOC || bt_fill(vm, flags) == 0) vmem_add1(vm, addr, size, BT_TYPE_SPAN_STATIC); else error = ENOMEM; VMEM_UNLOCK(vm); return (error); } /* * vmem_size: information about arenas size */ vmem_size_t vmem_size(vmem_t *vm, int typemask) { switch (typemask) { case VMEM_ALLOC: return vm->vm_inuse; case VMEM_FREE: return vm->vm_size - vm->vm_inuse; case VMEM_FREE|VMEM_ALLOC: return vm->vm_size; default: panic("vmem_size"); } } /* ---- debug */ #if defined(DDB) || defined(DIAGNOSTIC) static void bt_dump(const bt_t *, int (*)(const char *, ...) __printflike(1, 2)); static const char * bt_type_string(int type) { switch (type) { case BT_TYPE_BUSY: return "busy"; case BT_TYPE_FREE: return "free"; case BT_TYPE_SPAN: return "span"; case BT_TYPE_SPAN_STATIC: return "static span"; default: break; } return "BOGUS"; } static void bt_dump(const bt_t *bt, int (*pr)(const char *, ...)) { (*pr)("\t%p: %jx %jx, %d(%s)\n", bt, (intmax_t)bt->bt_start, (intmax_t)bt->bt_size, bt->bt_type, bt_type_string(bt->bt_type)); } static void vmem_dump(const vmem_t *vm , int (*pr)(const char *, ...) __printflike(1, 2)) { const bt_t *bt; int i; (*pr)("vmem %p '%s'\n", vm, vm->vm_name); TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) { bt_dump(bt, pr); } for (i = 0; i < VMEM_MAXORDER; i++) { const struct vmem_freelist *fl = &vm->vm_freelist[i]; if (LIST_EMPTY(fl)) { continue; } (*pr)("freelist[%d]\n", i); LIST_FOREACH(bt, fl, bt_freelist) { bt_dump(bt, pr); } } } #endif /* defined(DDB) || defined(DIAGNOSTIC) */ #if defined(DDB) static bt_t * vmem_whatis_lookup(vmem_t *vm, vmem_addr_t addr) { bt_t *bt; TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) { if (BT_ISSPAN_P(bt)) { continue; } if (bt->bt_start <= addr && addr <= BT_END(bt)) { return bt; } } return NULL; } void vmem_whatis(vmem_addr_t addr, int (*pr)(const char *, ...)) { vmem_t *vm; LIST_FOREACH(vm, &vmem_list, vm_alllist) { bt_t *bt; bt = vmem_whatis_lookup(vm, addr); if (bt == NULL) { continue; } (*pr)("%p is %p+%zu in VMEM '%s' (%s)\n", (void *)addr, (void *)bt->bt_start, (vmem_size_t)(addr - bt->bt_start), vm->vm_name, (bt->bt_type == BT_TYPE_BUSY) ? "allocated" : "free"); } } void vmem_printall(const char *modif, int (*pr)(const char *, ...)) { const vmem_t *vm; LIST_FOREACH(vm, &vmem_list, vm_alllist) { vmem_dump(vm, pr); } } void vmem_print(vmem_addr_t addr, const char *modif, int (*pr)(const char *, ...)) { const vmem_t *vm = (const void *)addr; vmem_dump(vm, pr); } #endif /* defined(DDB) */ #define vmem_printf printf #if defined(DIAGNOSTIC) static bool vmem_check_sanity(vmem_t *vm) { const bt_t *bt, *bt2; MPASS(vm != NULL); TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) { if (bt->bt_start > BT_END(bt)) { printf("corrupted tag\n"); bt_dump(bt, vmem_printf); return false; } } TAILQ_FOREACH(bt, &vm->vm_seglist, bt_seglist) { TAILQ_FOREACH(bt2, &vm->vm_seglist, bt_seglist) { if (bt == bt2) { continue; } if (BT_ISSPAN_P(bt) != BT_ISSPAN_P(bt2)) { continue; } if (bt->bt_start <= BT_END(bt2) && bt2->bt_start <= BT_END(bt)) { printf("overwrapped tags\n"); bt_dump(bt, vmem_printf); bt_dump(bt2, vmem_printf); return false; } } } return true; } static void vmem_check(vmem_t *vm) { if (!vmem_check_sanity(vm)) { panic("insanity vmem %p", vm); } } #endif /* defined(DIAGNOSTIC) */