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-rw-r--r--drivers/staging/zcache/tmem.c773
1 files changed, 0 insertions, 773 deletions
diff --git a/drivers/staging/zcache/tmem.c b/drivers/staging/zcache/tmem.c
deleted file mode 100644
index 56c8e606ad1..00000000000
--- a/drivers/staging/zcache/tmem.c
+++ /dev/null
@@ -1,773 +0,0 @@
-/*
- * In-kernel transcendent memory (generic implementation)
- *
- * Copyright (c) 2009-2011, Dan Magenheimer, Oracle Corp.
- *
- * The primary purpose of Transcendent Memory ("tmem") is to map object-oriented
- * "handles" (triples containing a pool id, and object id, and an index), to
- * pages in a page-accessible memory (PAM). Tmem references the PAM pages via
- * an abstract "pampd" (PAM page-descriptor), which can be operated on by a
- * set of functions (pamops). Each pampd contains some representation of
- * PAGE_SIZE bytes worth of data. Tmem must support potentially millions of
- * pages and must be able to insert, find, and delete these pages at a
- * potential frequency of thousands per second concurrently across many CPUs,
- * (and, if used with KVM, across many vcpus across many guests).
- * Tmem is tracked with a hierarchy of data structures, organized by
- * the elements in a handle-tuple: pool_id, object_id, and page index.
- * One or more "clients" (e.g. guests) each provide one or more tmem_pools.
- * Each pool, contains a hash table of rb_trees of tmem_objs. Each
- * tmem_obj contains a radix-tree-like tree of pointers, with intermediate
- * nodes called tmem_objnodes. Each leaf pointer in this tree points to
- * a pampd, which is accessible only through a small set of callbacks
- * registered by the PAM implementation (see tmem_register_pamops). Tmem
- * does all memory allocation via a set of callbacks registered by the tmem
- * host implementation (e.g. see tmem_register_hostops).
- */
-
-#include <linux/list.h>
-#include <linux/spinlock.h>
-#include <linux/atomic.h>
-
-#include "tmem.h"
-
-/* data structure sentinels used for debugging... see tmem.h */
-#define POOL_SENTINEL 0x87658765
-#define OBJ_SENTINEL 0x12345678
-#define OBJNODE_SENTINEL 0xfedcba09
-
-/*
- * A tmem host implementation must use this function to register callbacks
- * for memory allocation.
- */
-static struct tmem_hostops tmem_hostops;
-
-static void tmem_objnode_tree_init(void);
-
-void tmem_register_hostops(struct tmem_hostops *m)
-{
- tmem_objnode_tree_init();
- tmem_hostops = *m;
-}
-
-/*
- * A tmem host implementation must use this function to register
- * callbacks for a page-accessible memory (PAM) implementation
- */
-static struct tmem_pamops tmem_pamops;
-
-void tmem_register_pamops(struct tmem_pamops *m)
-{
- tmem_pamops = *m;
-}
-
-/*
- * Oid's are potentially very sparse and tmem_objs may have an indeterminately
- * short life, being added and deleted at a relatively high frequency.
- * So an rb_tree is an ideal data structure to manage tmem_objs. But because
- * of the potentially huge number of tmem_objs, each pool manages a hashtable
- * of rb_trees to reduce search, insert, delete, and rebalancing time.
- * Each hashbucket also has a lock to manage concurrent access.
- *
- * The following routines manage tmem_objs. When any tmem_obj is accessed,
- * the hashbucket lock must be held.
- */
-
-static struct tmem_obj
-*__tmem_obj_find(struct tmem_hashbucket*hb, struct tmem_oid *oidp,
- struct rb_node **parent, struct rb_node ***link)
-{
- struct rb_node *_parent = NULL, **rbnode;
- struct tmem_obj *obj = NULL;
-
- rbnode = &hb->obj_rb_root.rb_node;
- while (*rbnode) {
- BUG_ON(RB_EMPTY_NODE(*rbnode));
- _parent = *rbnode;
- obj = rb_entry(*rbnode, struct tmem_obj,
- rb_tree_node);
- switch (tmem_oid_compare(oidp, &obj->oid)) {
- case 0: /* equal */
- goto out;
- case -1:
- rbnode = &(*rbnode)->rb_left;
- break;
- case 1:
- rbnode = &(*rbnode)->rb_right;
- break;
- }
- }
-
- if (parent)
- *parent = _parent;
- if (link)
- *link = rbnode;
-
- obj = NULL;
-out:
- return obj;
-}
-
-
-/* searches for object==oid in pool, returns locked object if found */
-static struct tmem_obj *tmem_obj_find(struct tmem_hashbucket *hb,
- struct tmem_oid *oidp)
-{
- return __tmem_obj_find(hb, oidp, NULL, NULL);
-}
-
-static void tmem_pampd_destroy_all_in_obj(struct tmem_obj *);
-
-/* free an object that has no more pampds in it */
-static void tmem_obj_free(struct tmem_obj *obj, struct tmem_hashbucket *hb)
-{
- struct tmem_pool *pool;
-
- BUG_ON(obj == NULL);
- ASSERT_SENTINEL(obj, OBJ);
- BUG_ON(obj->pampd_count > 0);
- pool = obj->pool;
- BUG_ON(pool == NULL);
- if (obj->objnode_tree_root != NULL) /* may be "stump" with no leaves */
- tmem_pampd_destroy_all_in_obj(obj);
- BUG_ON(obj->objnode_tree_root != NULL);
- BUG_ON((long)obj->objnode_count != 0);
- atomic_dec(&pool->obj_count);
- BUG_ON(atomic_read(&pool->obj_count) < 0);
- INVERT_SENTINEL(obj, OBJ);
- obj->pool = NULL;
- tmem_oid_set_invalid(&obj->oid);
- rb_erase(&obj->rb_tree_node, &hb->obj_rb_root);
-}
-
-/*
- * initialize, and insert an tmem_object_root (called only if find failed)
- */
-static void tmem_obj_init(struct tmem_obj *obj, struct tmem_hashbucket *hb,
- struct tmem_pool *pool,
- struct tmem_oid *oidp)
-{
- struct rb_root *root = &hb->obj_rb_root;
- struct rb_node **new = NULL, *parent = NULL;
-
- BUG_ON(pool == NULL);
- atomic_inc(&pool->obj_count);
- obj->objnode_tree_height = 0;
- obj->objnode_tree_root = NULL;
- obj->pool = pool;
- obj->oid = *oidp;
- obj->objnode_count = 0;
- obj->pampd_count = 0;
- (*tmem_pamops.new_obj)(obj);
- SET_SENTINEL(obj, OBJ);
-
- if (__tmem_obj_find(hb, oidp, &parent, &new))
- BUG();
-
- rb_link_node(&obj->rb_tree_node, parent, new);
- rb_insert_color(&obj->rb_tree_node, root);
-}
-
-/*
- * Tmem is managed as a set of tmem_pools with certain attributes, such as
- * "ephemeral" vs "persistent". These attributes apply to all tmem_objs
- * and all pampds that belong to a tmem_pool. A tmem_pool is created
- * or deleted relatively rarely (for example, when a filesystem is
- * mounted or unmounted.
- */
-
-/* flush all data from a pool and, optionally, free it */
-static void tmem_pool_flush(struct tmem_pool *pool, bool destroy)
-{
- struct rb_node *rbnode;
- struct tmem_obj *obj;
- struct tmem_hashbucket *hb = &pool->hashbucket[0];
- int i;
-
- BUG_ON(pool == NULL);
- for (i = 0; i < TMEM_HASH_BUCKETS; i++, hb++) {
- spin_lock(&hb->lock);
- rbnode = rb_first(&hb->obj_rb_root);
- while (rbnode != NULL) {
- obj = rb_entry(rbnode, struct tmem_obj, rb_tree_node);
- rbnode = rb_next(rbnode);
- tmem_pampd_destroy_all_in_obj(obj);
- tmem_obj_free(obj, hb);
- (*tmem_hostops.obj_free)(obj, pool);
- }
- spin_unlock(&hb->lock);
- }
- if (destroy)
- list_del(&pool->pool_list);
-}
-
-/*
- * A tmem_obj contains a radix-tree-like tree in which the intermediate
- * nodes are called tmem_objnodes. (The kernel lib/radix-tree.c implementation
- * is very specialized and tuned for specific uses and is not particularly
- * suited for use from this code, though some code from the core algorithms has
- * been reused, thus the copyright notices below). Each tmem_objnode contains
- * a set of pointers which point to either a set of intermediate tmem_objnodes
- * or a set of of pampds.
- *
- * Portions Copyright (C) 2001 Momchil Velikov
- * Portions Copyright (C) 2001 Christoph Hellwig
- * Portions Copyright (C) 2005 SGI, Christoph Lameter <clameter@sgi.com>
- */
-
-struct tmem_objnode_tree_path {
- struct tmem_objnode *objnode;
- int offset;
-};
-
-/* objnode height_to_maxindex translation */
-static unsigned long tmem_objnode_tree_h2max[OBJNODE_TREE_MAX_PATH + 1];
-
-static void tmem_objnode_tree_init(void)
-{
- unsigned int ht, tmp;
-
- for (ht = 0; ht < ARRAY_SIZE(tmem_objnode_tree_h2max); ht++) {
- tmp = ht * OBJNODE_TREE_MAP_SHIFT;
- if (tmp >= OBJNODE_TREE_INDEX_BITS)
- tmem_objnode_tree_h2max[ht] = ~0UL;
- else
- tmem_objnode_tree_h2max[ht] =
- (~0UL >> (OBJNODE_TREE_INDEX_BITS - tmp - 1)) >> 1;
- }
-}
-
-static struct tmem_objnode *tmem_objnode_alloc(struct tmem_obj *obj)
-{
- struct tmem_objnode *objnode;
-
- ASSERT_SENTINEL(obj, OBJ);
- BUG_ON(obj->pool == NULL);
- ASSERT_SENTINEL(obj->pool, POOL);
- objnode = (*tmem_hostops.objnode_alloc)(obj->pool);
- if (unlikely(objnode == NULL))
- goto out;
- objnode->obj = obj;
- SET_SENTINEL(objnode, OBJNODE);
- memset(&objnode->slots, 0, sizeof(objnode->slots));
- objnode->slots_in_use = 0;
- obj->objnode_count++;
-out:
- return objnode;
-}
-
-static void tmem_objnode_free(struct tmem_objnode *objnode)
-{
- struct tmem_pool *pool;
- int i;
-
- BUG_ON(objnode == NULL);
- for (i = 0; i < OBJNODE_TREE_MAP_SIZE; i++)
- BUG_ON(objnode->slots[i] != NULL);
- ASSERT_SENTINEL(objnode, OBJNODE);
- INVERT_SENTINEL(objnode, OBJNODE);
- BUG_ON(objnode->obj == NULL);
- ASSERT_SENTINEL(objnode->obj, OBJ);
- pool = objnode->obj->pool;
- BUG_ON(pool == NULL);
- ASSERT_SENTINEL(pool, POOL);
- objnode->obj->objnode_count--;
- objnode->obj = NULL;
- (*tmem_hostops.objnode_free)(objnode, pool);
-}
-
-/*
- * lookup index in object and return associated pampd (or NULL if not found)
- */
-static void **__tmem_pampd_lookup_in_obj(struct tmem_obj *obj, uint32_t index)
-{
- unsigned int height, shift;
- struct tmem_objnode **slot = NULL;
-
- BUG_ON(obj == NULL);
- ASSERT_SENTINEL(obj, OBJ);
- BUG_ON(obj->pool == NULL);
- ASSERT_SENTINEL(obj->pool, POOL);
-
- height = obj->objnode_tree_height;
- if (index > tmem_objnode_tree_h2max[obj->objnode_tree_height])
- goto out;
- if (height == 0 && obj->objnode_tree_root) {
- slot = &obj->objnode_tree_root;
- goto out;
- }
- shift = (height-1) * OBJNODE_TREE_MAP_SHIFT;
- slot = &obj->objnode_tree_root;
- while (height > 0) {
- if (*slot == NULL)
- goto out;
- slot = (struct tmem_objnode **)
- ((*slot)->slots +
- ((index >> shift) & OBJNODE_TREE_MAP_MASK));
- shift -= OBJNODE_TREE_MAP_SHIFT;
- height--;
- }
-out:
- return slot != NULL ? (void **)slot : NULL;
-}
-
-static void *tmem_pampd_lookup_in_obj(struct tmem_obj *obj, uint32_t index)
-{
- struct tmem_objnode **slot;
-
- slot = (struct tmem_objnode **)__tmem_pampd_lookup_in_obj(obj, index);
- return slot != NULL ? *slot : NULL;
-}
-
-static void *tmem_pampd_replace_in_obj(struct tmem_obj *obj, uint32_t index,
- void *new_pampd)
-{
- struct tmem_objnode **slot;
- void *ret = NULL;
-
- slot = (struct tmem_objnode **)__tmem_pampd_lookup_in_obj(obj, index);
- if ((slot != NULL) && (*slot != NULL)) {
- void *old_pampd = *(void **)slot;
- *(void **)slot = new_pampd;
- (*tmem_pamops.free)(old_pampd, obj->pool, NULL, 0);
- ret = new_pampd;
- }
- return ret;
-}
-
-static int tmem_pampd_add_to_obj(struct tmem_obj *obj, uint32_t index,
- void *pampd)
-{
- int ret = 0;
- struct tmem_objnode *objnode = NULL, *newnode, *slot;
- unsigned int height, shift;
- int offset = 0;
-
- /* if necessary, extend the tree to be higher */
- if (index > tmem_objnode_tree_h2max[obj->objnode_tree_height]) {
- height = obj->objnode_tree_height + 1;
- if (index > tmem_objnode_tree_h2max[height])
- while (index > tmem_objnode_tree_h2max[height])
- height++;
- if (obj->objnode_tree_root == NULL) {
- obj->objnode_tree_height = height;
- goto insert;
- }
- do {
- newnode = tmem_objnode_alloc(obj);
- if (!newnode) {
- ret = -ENOMEM;
- goto out;
- }
- newnode->slots[0] = obj->objnode_tree_root;
- newnode->slots_in_use = 1;
- obj->objnode_tree_root = newnode;
- obj->objnode_tree_height++;
- } while (height > obj->objnode_tree_height);
- }
-insert:
- slot = obj->objnode_tree_root;
- height = obj->objnode_tree_height;
- shift = (height-1) * OBJNODE_TREE_MAP_SHIFT;
- while (height > 0) {
- if (slot == NULL) {
- /* add a child objnode. */
- slot = tmem_objnode_alloc(obj);
- if (!slot) {
- ret = -ENOMEM;
- goto out;
- }
- if (objnode) {
-
- objnode->slots[offset] = slot;
- objnode->slots_in_use++;
- } else
- obj->objnode_tree_root = slot;
- }
- /* go down a level */
- offset = (index >> shift) & OBJNODE_TREE_MAP_MASK;
- objnode = slot;
- slot = objnode->slots[offset];
- shift -= OBJNODE_TREE_MAP_SHIFT;
- height--;
- }
- BUG_ON(slot != NULL);
- if (objnode) {
- objnode->slots_in_use++;
- objnode->slots[offset] = pampd;
- } else
- obj->objnode_tree_root = pampd;
- obj->pampd_count++;
-out:
- return ret;
-}
-
-static void *tmem_pampd_delete_from_obj(struct tmem_obj *obj, uint32_t index)
-{
- struct tmem_objnode_tree_path path[OBJNODE_TREE_MAX_PATH + 1];
- struct tmem_objnode_tree_path *pathp = path;
- struct tmem_objnode *slot = NULL;
- unsigned int height, shift;
- int offset;
-
- BUG_ON(obj == NULL);
- ASSERT_SENTINEL(obj, OBJ);
- BUG_ON(obj->pool == NULL);
- ASSERT_SENTINEL(obj->pool, POOL);
- height = obj->objnode_tree_height;
- if (index > tmem_objnode_tree_h2max[height])
- goto out;
- slot = obj->objnode_tree_root;
- if (height == 0 && obj->objnode_tree_root) {
- obj->objnode_tree_root = NULL;
- goto out;
- }
- shift = (height - 1) * OBJNODE_TREE_MAP_SHIFT;
- pathp->objnode = NULL;
- do {
- if (slot == NULL)
- goto out;
- pathp++;
- offset = (index >> shift) & OBJNODE_TREE_MAP_MASK;
- pathp->offset = offset;
- pathp->objnode = slot;
- slot = slot->slots[offset];
- shift -= OBJNODE_TREE_MAP_SHIFT;
- height--;
- } while (height > 0);
- if (slot == NULL)
- goto out;
- while (pathp->objnode) {
- pathp->objnode->slots[pathp->offset] = NULL;
- pathp->objnode->slots_in_use--;
- if (pathp->objnode->slots_in_use) {
- if (pathp->objnode == obj->objnode_tree_root) {
- while (obj->objnode_tree_height > 0 &&
- obj->objnode_tree_root->slots_in_use == 1 &&
- obj->objnode_tree_root->slots[0]) {
- struct tmem_objnode *to_free =
- obj->objnode_tree_root;
-
- obj->objnode_tree_root =
- to_free->slots[0];
- obj->objnode_tree_height--;
- to_free->slots[0] = NULL;
- to_free->slots_in_use = 0;
- tmem_objnode_free(to_free);
- }
- }
- goto out;
- }
- tmem_objnode_free(pathp->objnode); /* 0 slots used, free it */
- pathp--;
- }
- obj->objnode_tree_height = 0;
- obj->objnode_tree_root = NULL;
-
-out:
- if (slot != NULL)
- obj->pampd_count--;
- BUG_ON(obj->pampd_count < 0);
- return slot;
-}
-
-/* recursively walk the objnode_tree destroying pampds and objnodes */
-static void tmem_objnode_node_destroy(struct tmem_obj *obj,
- struct tmem_objnode *objnode,
- unsigned int ht)
-{
- int i;
-
- if (ht == 0)
- return;
- for (i = 0; i < OBJNODE_TREE_MAP_SIZE; i++) {
- if (objnode->slots[i]) {
- if (ht == 1) {
- obj->pampd_count--;
- (*tmem_pamops.free)(objnode->slots[i],
- obj->pool, NULL, 0);
- objnode->slots[i] = NULL;
- continue;
- }
- tmem_objnode_node_destroy(obj, objnode->slots[i], ht-1);
- tmem_objnode_free(objnode->slots[i]);
- objnode->slots[i] = NULL;
- }
- }
-}
-
-static void tmem_pampd_destroy_all_in_obj(struct tmem_obj *obj)
-{
- if (obj->objnode_tree_root == NULL)
- return;
- if (obj->objnode_tree_height == 0) {
- obj->pampd_count--;
- (*tmem_pamops.free)(obj->objnode_tree_root, obj->pool, NULL, 0);
- } else {
- tmem_objnode_node_destroy(obj, obj->objnode_tree_root,
- obj->objnode_tree_height);
- tmem_objnode_free(obj->objnode_tree_root);
- obj->objnode_tree_height = 0;
- }
- obj->objnode_tree_root = NULL;
- (*tmem_pamops.free_obj)(obj->pool, obj);
-}
-
-/*
- * Tmem is operated on by a set of well-defined actions:
- * "put", "get", "flush", "flush_object", "new pool" and "destroy pool".
- * (The tmem ABI allows for subpages and exchanges but these operations
- * are not included in this implementation.)
- *
- * These "tmem core" operations are implemented in the following functions.
- */
-
-/*
- * "Put" a page, e.g. copy a page from the kernel into newly allocated
- * PAM space (if such space is available). Tmem_put is complicated by
- * a corner case: What if a page with matching handle already exists in
- * tmem? To guarantee coherency, one of two actions is necessary: Either
- * the data for the page must be overwritten, or the page must be
- * "flushed" so that the data is not accessible to a subsequent "get".
- * Since these "duplicate puts" are relatively rare, this implementation
- * always flushes for simplicity.
- */
-int tmem_put(struct tmem_pool *pool, struct tmem_oid *oidp, uint32_t index,
- char *data, size_t size, bool raw, bool ephemeral)
-{
- struct tmem_obj *obj = NULL, *objfound = NULL, *objnew = NULL;
- void *pampd = NULL, *pampd_del = NULL;
- int ret = -ENOMEM;
- struct tmem_hashbucket *hb;
-
- hb = &pool->hashbucket[tmem_oid_hash(oidp)];
- spin_lock(&hb->lock);
- obj = objfound = tmem_obj_find(hb, oidp);
- if (obj != NULL) {
- pampd = tmem_pampd_lookup_in_obj(objfound, index);
- if (pampd != NULL) {
- /* if found, is a dup put, flush the old one */
- pampd_del = tmem_pampd_delete_from_obj(obj, index);
- BUG_ON(pampd_del != pampd);
- (*tmem_pamops.free)(pampd, pool, oidp, index);
- if (obj->pampd_count == 0) {
- objnew = obj;
- objfound = NULL;
- }
- pampd = NULL;
- }
- } else {
- obj = objnew = (*tmem_hostops.obj_alloc)(pool);
- if (unlikely(obj == NULL)) {
- ret = -ENOMEM;
- goto out;
- }
- tmem_obj_init(obj, hb, pool, oidp);
- }
- BUG_ON(obj == NULL);
- BUG_ON(((objnew != obj) && (objfound != obj)) || (objnew == objfound));
- pampd = (*tmem_pamops.create)(data, size, raw, ephemeral,
- obj->pool, &obj->oid, index);
- if (unlikely(pampd == NULL))
- goto free;
- ret = tmem_pampd_add_to_obj(obj, index, pampd);
- if (unlikely(ret == -ENOMEM))
- /* may have partially built objnode tree ("stump") */
- goto delete_and_free;
- goto out;
-
-delete_and_free:
- (void)tmem_pampd_delete_from_obj(obj, index);
-free:
- if (pampd)
- (*tmem_pamops.free)(pampd, pool, NULL, 0);
- if (objnew) {
- tmem_obj_free(objnew, hb);
- (*tmem_hostops.obj_free)(objnew, pool);
- }
-out:
- spin_unlock(&hb->lock);
- return ret;
-}
-
-/*
- * "Get" a page, e.g. if one can be found, copy the tmem page with the
- * matching handle from PAM space to the kernel. By tmem definition,
- * when a "get" is successful on an ephemeral page, the page is "flushed",
- * and when a "get" is successful on a persistent page, the page is retained
- * in tmem. Note that to preserve
- * coherency, "get" can never be skipped if tmem contains the data.
- * That is, if a get is done with a certain handle and fails, any
- * subsequent "get" must also fail (unless of course there is a
- * "put" done with the same handle).
-
- */
-int tmem_get(struct tmem_pool *pool, struct tmem_oid *oidp, uint32_t index,
- char *data, size_t *size, bool raw, int get_and_free)
-{
- struct tmem_obj *obj;
- void *pampd;
- bool ephemeral = is_ephemeral(pool);
- int ret = -1;
- struct tmem_hashbucket *hb;
- bool free = (get_and_free == 1) || ((get_and_free == 0) && ephemeral);
- bool lock_held = false;
-
- hb = &pool->hashbucket[tmem_oid_hash(oidp)];
- spin_lock(&hb->lock);
- lock_held = true;
- obj = tmem_obj_find(hb, oidp);
- if (obj == NULL)
- goto out;
- if (free)
- pampd = tmem_pampd_delete_from_obj(obj, index);
- else
- pampd = tmem_pampd_lookup_in_obj(obj, index);
- if (pampd == NULL)
- goto out;
- if (free) {
- if (obj->pampd_count == 0) {
- tmem_obj_free(obj, hb);
- (*tmem_hostops.obj_free)(obj, pool);
- obj = NULL;
- }
- }
- if (tmem_pamops.is_remote(pampd)) {
- lock_held = false;
- spin_unlock(&hb->lock);
- }
- if (free)
- ret = (*tmem_pamops.get_data_and_free)(
- data, size, raw, pampd, pool, oidp, index);
- else
- ret = (*tmem_pamops.get_data)(
- data, size, raw, pampd, pool, oidp, index);
- if (ret < 0)
- goto out;
- ret = 0;
-out:
- if (lock_held)
- spin_unlock(&hb->lock);
- return ret;
-}
-
-/*
- * If a page in tmem matches the handle, "flush" this page from tmem such
- * that any subsequent "get" does not succeed (unless, of course, there
- * was another "put" with the same handle).
- */
-int tmem_flush_page(struct tmem_pool *pool,
- struct tmem_oid *oidp, uint32_t index)
-{
- struct tmem_obj *obj;
- void *pampd;
- int ret = -1;
- struct tmem_hashbucket *hb;
-
- hb = &pool->hashbucket[tmem_oid_hash(oidp)];
- spin_lock(&hb->lock);
- obj = tmem_obj_find(hb, oidp);
- if (obj == NULL)
- goto out;
- pampd = tmem_pampd_delete_from_obj(obj, index);
- if (pampd == NULL)
- goto out;
- (*tmem_pamops.free)(pampd, pool, oidp, index);
- if (obj->pampd_count == 0) {
- tmem_obj_free(obj, hb);
- (*tmem_hostops.obj_free)(obj, pool);
- }
- ret = 0;
-
-out:
- spin_unlock(&hb->lock);
- return ret;
-}
-
-/*
- * If a page in tmem matches the handle, replace the page so that any
- * subsequent "get" gets the new page. Returns 0 if
- * there was a page to replace, else returns -1.
- */
-int tmem_replace(struct tmem_pool *pool, struct tmem_oid *oidp,
- uint32_t index, void *new_pampd)
-{
- struct tmem_obj *obj;
- int ret = -1;
- struct tmem_hashbucket *hb;
-
- hb = &pool->hashbucket[tmem_oid_hash(oidp)];
- spin_lock(&hb->lock);
- obj = tmem_obj_find(hb, oidp);
- if (obj == NULL)
- goto out;
- new_pampd = tmem_pampd_replace_in_obj(obj, index, new_pampd);
- ret = (*tmem_pamops.replace_in_obj)(new_pampd, obj);
-out:
- spin_unlock(&hb->lock);
- return ret;
-}
-
-/*
- * "Flush" all pages in tmem matching this oid.
- */
-int tmem_flush_object(struct tmem_pool *pool, struct tmem_oid *oidp)
-{
- struct tmem_obj *obj;
- struct tmem_hashbucket *hb;
- int ret = -1;
-
- hb = &pool->hashbucket[tmem_oid_hash(oidp)];
- spin_lock(&hb->lock);
- obj = tmem_obj_find(hb, oidp);
- if (obj == NULL)
- goto out;
- tmem_pampd_destroy_all_in_obj(obj);
- tmem_obj_free(obj, hb);
- (*tmem_hostops.obj_free)(obj, pool);
- ret = 0;
-
-out:
- spin_unlock(&hb->lock);
- return ret;
-}
-
-/*
- * "Flush" all pages (and tmem_objs) from this tmem_pool and disable
- * all subsequent access to this tmem_pool.
- */
-int tmem_destroy_pool(struct tmem_pool *pool)
-{
- int ret = -1;
-
- if (pool == NULL)
- goto out;
- tmem_pool_flush(pool, 1);
- ret = 0;
-out:
- return ret;
-}
-
-static LIST_HEAD(tmem_global_pool_list);
-
-/*
- * Create a new tmem_pool with the provided flag and return
- * a pool id provided by the tmem host implementation.
- */
-void tmem_new_pool(struct tmem_pool *pool, uint32_t flags)
-{
- int persistent = flags & TMEM_POOL_PERSIST;
- int shared = flags & TMEM_POOL_SHARED;
- struct tmem_hashbucket *hb = &pool->hashbucket[0];
- int i;
-
- for (i = 0; i < TMEM_HASH_BUCKETS; i++, hb++) {
- hb->obj_rb_root = RB_ROOT;
- spin_lock_init(&hb->lock);
- }
- INIT_LIST_HEAD(&pool->pool_list);
- atomic_set(&pool->obj_count, 0);
- SET_SENTINEL(pool, POOL);
- list_add_tail(&pool->pool_list, &tmem_global_pool_list);
- pool->persistent = persistent;
- pool->shared = shared;
-}