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[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [Xen-devel] [PATCH v2 3/9] tmem: Delete deduplication (and tze) code.
Couple of reasons:
- It can lead to security issues (see row-hammer, KSM and such
attacks).
- Code is quite complex.
- Deduplication is good if the pages themselves are the same
but that is hardly guaranteed.
- We got some gains (if pages are deduped) but at the cost of
making code less maintainable.
- tze depends on deduplication code.
As such, deleting it.
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
---
v1: First submission.
v2: Squash " tmem: Wrap tmem dedup code with CONFIG_TMEM_DEDUP"
and "tmem: Wrap tmem tze code with CONFIG_TMEM_TZE"
---
docs/misc/xen-command-line.markdown | 6 -
xen/common/tmem.c | 310 +-----------------------------------
xen/common/tmem_control.c | 7 -
xen/common/tmem_xen.c | 28 ----
xen/include/xen/tmem_xen.h | 115 -------------
5 files changed, 3 insertions(+), 463 deletions(-)
diff --git a/docs/misc/xen-command-line.markdown
b/docs/misc/xen-command-line.markdown
index 8ff57fa..cd9534b 100644
--- a/docs/misc/xen-command-line.markdown
+++ b/docs/misc/xen-command-line.markdown
@@ -1500,15 +1500,9 @@ pages) must also be specified via the tbuf\_size
parameter.
### tmem\_compress
> `= <boolean>`
-### tmem\_dedup
-> `= <boolean>`
-
### tmem\_shared\_auth
> `= <boolean>`
-### tmem\_tze
-> `= <integer>`
-
### tsc
> `= unstable | skewed | stable:socket`
diff --git a/xen/common/tmem.c b/xen/common/tmem.c
index efaafc4..cf5271c 100644
--- a/xen/common/tmem.c
+++ b/xen/common/tmem.c
@@ -71,10 +71,7 @@ struct tmem_page_descriptor {
pagesize_t size; /* 0 == PAGE_SIZE (pfp), -1 == data invalid,
else compressed data (cdata). */
uint32_t index;
- /* Must hold pcd_tree_rwlocks[firstbyte] to use pcd pointer/siblings. */
- uint16_t firstbyte; /* NON_SHAREABLE->pfp otherwise->pcd. */
bool_t eviction_attempted; /* CHANGE TO lifetimes? (settable). */
- struct list_head pcd_siblings;
union {
struct page_info *pfp; /* Page frame pointer. */
char *cdata; /* Compressed data. */
@@ -92,17 +89,11 @@ struct tmem_page_content_descriptor {
union {
struct page_info *pfp; /* Page frame pointer. */
char *cdata; /* If compression_enabled. */
- char *tze; /* If !compression_enabled, trailing zeroes eliminated. */
};
- struct list_head pgp_list;
- struct rb_node pcd_rb_tree_node;
- uint32_t pgp_ref_count;
pagesize_t size; /* If compression_enabled -> 0<size<PAGE_SIZE (*cdata)
* else if tze, 0<=size<PAGE_SIZE, rounded up to mult of 8
* else PAGE_SIZE -> *pfp. */
};
-struct rb_root pcd_tree_roots[256]; /* Choose based on first byte of page. */
-rwlock_t pcd_tree_rwlocks[256]; /* Poor man's concurrency for now. */
static int tmem_initialized = 0;
@@ -262,230 +253,6 @@ static void tmem_persistent_pool_page_put(void *page_va)
*/
#define NOT_SHAREABLE ((uint16_t)-1UL)
-static int pcd_copy_to_client(xen_pfn_t cmfn, struct tmem_page_descriptor *pgp)
-{
- uint8_t firstbyte = pgp->firstbyte;
- struct tmem_page_content_descriptor *pcd;
- int ret;
-
- ASSERT(tmem_dedup_enabled());
- read_lock(&pcd_tree_rwlocks[firstbyte]);
- pcd = pgp->pcd;
- if ( pgp->size < PAGE_SIZE && pgp->size != 0 &&
- pcd->size < PAGE_SIZE && pcd->size != 0 )
- ret = tmem_decompress_to_client(cmfn, pcd->cdata, pcd->size,
- tmem_cli_buf_null);
- else if ( tmem_tze_enabled() && pcd->size < PAGE_SIZE )
- ret = tmem_copy_tze_to_client(cmfn, pcd->tze, pcd->size);
- else
- ret = tmem_copy_to_client(cmfn, pcd->pfp, tmem_cli_buf_null);
- read_unlock(&pcd_tree_rwlocks[firstbyte]);
- return ret;
-}
-
-/*
- * Ensure pgp no longer points to pcd, nor vice-versa.
- * Take pcd rwlock unless have_pcd_rwlock is set, always unlock when done.
- */
-static void pcd_disassociate(struct tmem_page_descriptor *pgp, struct
tmem_pool *pool, bool_t have_pcd_rwlock)
-{
- struct tmem_page_content_descriptor *pcd = pgp->pcd;
- struct page_info *pfp = pgp->pcd->pfp;
- uint16_t firstbyte = pgp->firstbyte;
- char *pcd_tze = pgp->pcd->tze;
- pagesize_t pcd_size = pcd->size;
- pagesize_t pgp_size = pgp->size;
- char *pcd_cdata = pgp->pcd->cdata;
- pagesize_t pcd_csize = pgp->pcd->size;
-
- ASSERT(tmem_dedup_enabled());
- ASSERT(firstbyte != NOT_SHAREABLE);
- ASSERT(firstbyte < 256);
-
- if ( have_pcd_rwlock )
- ASSERT_WRITELOCK(&pcd_tree_rwlocks[firstbyte]);
- else
- write_lock(&pcd_tree_rwlocks[firstbyte]);
- list_del_init(&pgp->pcd_siblings);
- pgp->pcd = NULL;
- pgp->firstbyte = NOT_SHAREABLE;
- pgp->size = -1;
- if ( --pcd->pgp_ref_count )
- {
- write_unlock(&pcd_tree_rwlocks[firstbyte]);
- return;
- }
-
- /* No more references to this pcd, recycle it and the physical page. */
- ASSERT(list_empty(&pcd->pgp_list));
- pcd->pfp = NULL;
- /* Remove pcd from rbtree. */
- rb_erase(&pcd->pcd_rb_tree_node,&pcd_tree_roots[firstbyte]);
- /* Reinit the struct for safety for now. */
- RB_CLEAR_NODE(&pcd->pcd_rb_tree_node);
- /* Now free up the pcd memory. */
- tmem_free(pcd, NULL);
- atomic_dec_and_assert(global_pcd_count);
- if ( pgp_size != 0 && pcd_size < PAGE_SIZE )
- {
- /* Compressed data. */
- tmem_free(pcd_cdata, pool);
- tmem_stats.pcd_tot_csize -= pcd_csize;
- }
- else if ( pcd_size != PAGE_SIZE )
- {
- /* Trailing zero data. */
- tmem_stats.pcd_tot_tze_size -= pcd_size;
- if ( pcd_size )
- tmem_free(pcd_tze, pool);
- } else {
- /* Real physical page. */
- if ( tmem_tze_enabled() )
- tmem_stats.pcd_tot_tze_size -= PAGE_SIZE;
- if ( tmem_compression_enabled() )
- tmem_stats.pcd_tot_csize -= PAGE_SIZE;
- tmem_free_page(pool,pfp);
- }
- write_unlock(&pcd_tree_rwlocks[firstbyte]);
-}
-
-
-static int pcd_associate(struct tmem_page_descriptor *pgp, char *cdata,
pagesize_t csize)
-{
- struct rb_node **new, *parent = NULL;
- struct rb_root *root;
- struct tmem_page_content_descriptor *pcd;
- int cmp;
- pagesize_t pfp_size = 0;
- uint8_t firstbyte = (cdata == NULL) ? tmem_get_first_byte(pgp->pfp) :
*cdata;
- int ret = 0;
-
- if ( !tmem_dedup_enabled() )
- return 0;
- ASSERT(pgp->us.obj != NULL);
- ASSERT(pgp->us.obj->pool != NULL);
- ASSERT(!pgp->us.obj->pool->persistent);
- if ( cdata == NULL )
- {
- ASSERT(pgp->pfp != NULL);
- pfp_size = PAGE_SIZE;
- if ( tmem_tze_enabled() )
- {
- pfp_size = tmem_tze_pfp_scan(pgp->pfp);
- if ( pfp_size > PCD_TZE_MAX_SIZE )
- pfp_size = PAGE_SIZE;
- }
- ASSERT(pfp_size <= PAGE_SIZE);
- ASSERT(!(pfp_size & (sizeof(uint64_t)-1)));
- }
- write_lock(&pcd_tree_rwlocks[firstbyte]);
-
- /* Look for page match. */
- root = &pcd_tree_roots[firstbyte];
- new = &(root->rb_node);
- while ( *new )
- {
- pcd = container_of(*new, struct tmem_page_content_descriptor,
pcd_rb_tree_node);
- parent = *new;
- /* Compare new entry and rbtree entry, set cmp accordingly. */
- if ( cdata != NULL )
- {
- if ( pcd->size < PAGE_SIZE )
- /* Both new entry and rbtree entry are compressed. */
- cmp = tmem_pcd_cmp(cdata,csize,pcd->cdata,pcd->size);
- else
- /* New entry is compressed, rbtree entry is not. */
- cmp = -1;
- } else if ( pcd->size < PAGE_SIZE )
- /* Rbtree entry is compressed, rbtree entry is not. */
- cmp = 1;
- else if ( tmem_tze_enabled() ) {
- if ( pcd->size < PAGE_SIZE )
- /* Both new entry and rbtree entry are trailing zero. */
- cmp = tmem_tze_pfp_cmp(pgp->pfp,pfp_size,pcd->tze,pcd->size);
- else
- /* New entry is trailing zero, rbtree entry is not. */
- cmp = tmem_tze_pfp_cmp(pgp->pfp,pfp_size,pcd->pfp,PAGE_SIZE);
- } else {
- /* Both new entry and rbtree entry are full physical pages. */
- ASSERT(pgp->pfp != NULL);
- ASSERT(pcd->pfp != NULL);
- cmp = tmem_page_cmp(pgp->pfp,pcd->pfp);
- }
-
- /* Walk tree or match depending on cmp. */
- if ( cmp < 0 )
- new = &((*new)->rb_left);
- else if ( cmp > 0 )
- new = &((*new)->rb_right);
- else
- {
- /*
- * Match! if not compressed, free the no-longer-needed page
- * but if compressed, data is assumed static so don't free!
- */
- if ( cdata == NULL )
- tmem_free_page(pgp->us.obj->pool,pgp->pfp);
- tmem_stats.deduped_puts++;
- goto match;
- }
- }
-
- /* Exited while loop with no match, so alloc a pcd and put it in the tree.
*/
- if ( (pcd = tmem_malloc(sizeof(struct tmem_page_content_descriptor),
NULL)) == NULL )
- {
- ret = -ENOMEM;
- goto unlock;
- } else if ( cdata != NULL ) {
- if ( (pcd->cdata = tmem_malloc(csize,pgp->us.obj->pool)) == NULL )
- {
- tmem_free(pcd, NULL);
- ret = -ENOMEM;
- goto unlock;
- }
- }
- atomic_inc_and_max(global_pcd_count);
- RB_CLEAR_NODE(&pcd->pcd_rb_tree_node); /* Is this necessary? */
- INIT_LIST_HEAD(&pcd->pgp_list); /* Is this necessary? */
- pcd->pgp_ref_count = 0;
- if ( cdata != NULL )
- {
- memcpy(pcd->cdata,cdata,csize);
- pcd->size = csize;
- tmem_stats.pcd_tot_csize += csize;
- } else if ( pfp_size == 0 ) {
- ASSERT(tmem_tze_enabled());
- pcd->size = 0;
- pcd->tze = NULL;
- } else if ( pfp_size < PAGE_SIZE &&
- ((pcd->tze = tmem_malloc(pfp_size,pgp->us.obj->pool)) != NULL) ) {
- tmem_tze_copy_from_pfp(pcd->tze,pgp->pfp,pfp_size);
- pcd->size = pfp_size;
- tmem_stats.pcd_tot_tze_size += pfp_size;
- tmem_free_page(pgp->us.obj->pool,pgp->pfp);
- } else {
- pcd->pfp = pgp->pfp;
- pcd->size = PAGE_SIZE;
- if ( tmem_tze_enabled() )
- tmem_stats.pcd_tot_tze_size += PAGE_SIZE;
- if ( tmem_compression_enabled() )
- tmem_stats.pcd_tot_csize += PAGE_SIZE;
- }
- rb_link_node(&pcd->pcd_rb_tree_node, parent, new);
- rb_insert_color(&pcd->pcd_rb_tree_node, root);
-
-match:
- pcd->pgp_ref_count++;
- list_add(&pgp->pcd_siblings,&pcd->pgp_list);
- pgp->firstbyte = firstbyte;
- pgp->eviction_attempted = 0;
- pgp->pcd = pcd;
-
-unlock:
- write_unlock(&pcd_tree_rwlocks[firstbyte]);
- return ret;
-}
-
/************ PAGE DESCRIPTOR MANIPULATION ROUTINES *******************/
/* Allocate a struct tmem_page_descriptor and associate it with an object. */
@@ -503,12 +270,6 @@ static struct tmem_page_descriptor *pgp_alloc(struct
tmem_object_root *obj)
INIT_LIST_HEAD(&pgp->global_eph_pages);
INIT_LIST_HEAD(&pgp->us.client_eph_pages);
pgp->pfp = NULL;
- if ( tmem_dedup_enabled() )
- {
- pgp->firstbyte = NOT_SHAREABLE;
- pgp->eviction_attempted = 0;
- INIT_LIST_HEAD(&pgp->pcd_siblings);
- }
pgp->size = -1;
pgp->index = -1;
pgp->timestamp = get_cycles();
@@ -533,9 +294,7 @@ static void pgp_free_data(struct tmem_page_descriptor *pgp,
struct tmem_pool *po
if ( pgp->pfp == NULL )
return;
- if ( tmem_dedup_enabled() && pgp->firstbyte != NOT_SHAREABLE )
- pcd_disassociate(pgp,pool,0); /* pgp->size lost. */
- else if ( pgp_size )
+ if ( pgp_size )
tmem_free(pgp->cdata, pool);
else
tmem_free_page(pgp->us.obj->pool,pgp->pfp);
@@ -1141,31 +900,11 @@ static bool_t tmem_try_to_evict_pgp(struct
tmem_page_descriptor *pgp, bool_t *ho
{
struct tmem_object_root *obj = pgp->us.obj;
struct tmem_pool *pool = obj->pool;
- struct client *client = pool->client;
- uint16_t firstbyte = pgp->firstbyte;
if ( pool->is_dying )
return 0;
if ( spin_trylock(&obj->obj_spinlock) )
{
- if ( tmem_dedup_enabled() )
- {
- firstbyte = pgp->firstbyte;
- if ( firstbyte == NOT_SHAREABLE )
- goto obj_unlock;
- ASSERT(firstbyte < 256);
- if ( !write_trylock(&pcd_tree_rwlocks[firstbyte]) )
- goto obj_unlock;
- if ( pgp->pcd->pgp_ref_count > 1 && !pgp->eviction_attempted )
- {
- pgp->eviction_attempted++;
- list_del(&pgp->global_eph_pages);
-
list_add_tail(&pgp->global_eph_pages,&tmem_global.ephemeral_page_list);
- list_del(&pgp->us.client_eph_pages);
-
list_add_tail(&pgp->us.client_eph_pages,&client->ephemeral_page_list);
- goto pcd_unlock;
- }
- }
if ( obj->pgp_count > 1 )
return 1;
if ( write_trylock(&pool->pool_rwlock) )
@@ -1173,10 +912,6 @@ static bool_t tmem_try_to_evict_pgp(struct
tmem_page_descriptor *pgp, bool_t *ho
*hold_pool_rwlock = 1;
return 1;
}
-pcd_unlock:
- if ( tmem_dedup_enabled() )
- write_unlock(&pcd_tree_rwlocks[firstbyte]);
-obj_unlock:
spin_unlock(&obj->obj_spinlock);
}
return 0;
@@ -1232,11 +967,6 @@ found:
ASSERT_SPINLOCK(&obj->obj_spinlock);
pgp_del = pgp_delete_from_obj(obj, pgp->index);
ASSERT(pgp_del == pgp);
- if ( tmem_dedup_enabled() && pgp->firstbyte != NOT_SHAREABLE )
- {
- ASSERT(pgp->pcd->pgp_ref_count == 1 || pgp->eviction_attempted);
- pcd_disassociate(pgp,pool,1);
- }
/* pgp already delist, so call pgp_free directly. */
pgp_free(pgp);
@@ -1303,9 +1033,6 @@ static int do_tmem_put_compress(struct
tmem_page_descriptor *pgp, xen_pfn_t cmfn
else if ( (size == 0) || (size >= tmem_mempool_maxalloc) ) {
ret = 0;
goto out;
- } else if ( tmem_dedup_enabled() && !is_persistent(pgp->us.obj->pool) ) {
- if ( (ret = pcd_associate(pgp,dst,size)) == -ENOMEM )
- goto out;
} else if ( (p = tmem_malloc(size,pgp->us.obj->pool)) == NULL ) {
ret = -ENOMEM;
goto out;
@@ -1365,11 +1092,6 @@ copy_uncompressed:
ret = tmem_copy_from_client(pgp->pfp, cmfn, tmem_cli_buf_null);
if ( ret < 0 )
goto bad_copy;
- if ( tmem_dedup_enabled() && !is_persistent(pool) )
- {
- if ( pcd_associate(pgp,NULL,0) == -ENOMEM )
- goto failed_dup;
- }
done:
/* Successfully replaced data, clean up and return success. */
@@ -1506,15 +1228,6 @@ copy_uncompressed:
if ( ret < 0 )
goto bad_copy;
- if ( tmem_dedup_enabled() && !is_persistent(pool) )
- {
- if ( pcd_associate(pgp, NULL, 0) == -ENOMEM )
- {
- ret = -ENOMEM;
- goto del_pgp_from_obj;
- }
- }
-
insert_page:
if ( !is_persistent(pool) )
{
@@ -1601,10 +1314,7 @@ static int do_tmem_get(struct tmem_pool *pool,
return 0;
}
ASSERT(pgp->size != -1);
- if ( tmem_dedup_enabled() && !is_persistent(pool) &&
- pgp->firstbyte != NOT_SHAREABLE )
- rc = pcd_copy_to_client(cmfn, pgp);
- else if ( pgp->size != 0 )
+ if ( pgp->size != 0 )
{
rc = tmem_decompress_to_client(cmfn, pgp->cdata, pgp->size, clibuf);
}
@@ -2362,29 +2072,15 @@ unsigned long tmem_freeable_pages(void)
/* Called at hypervisor startup. */
static int __init init_tmem(void)
{
- int i;
if ( !tmem_enabled() )
return 0;
- if ( tmem_dedup_enabled() )
- for (i = 0; i < 256; i++ )
- {
- pcd_tree_roots[i] = RB_ROOT;
- rwlock_init(&pcd_tree_rwlocks[i]);
- }
-
if ( !tmem_mempool_init() )
return 0;
if ( tmem_init() )
{
- printk("tmem: initialized comp=%d dedup=%d tze=%d\n",
- tmem_compression_enabled(), tmem_dedup_enabled(),
tmem_tze_enabled());
- if (
tmem_dedup_enabled()&&tmem_compression_enabled()&&tmem_tze_enabled() )
- {
- tmem_tze_disable();
- printk("tmem: tze and compression not compatible, disabling
tze\n");
- }
+ printk("tmem: initialized comp=%d\n", tmem_compression_enabled());
tmem_initialized = 1;
}
else
diff --git a/xen/common/tmem_control.c b/xen/common/tmem_control.c
index ca34852..cda327b 100644
--- a/xen/common/tmem_control.c
+++ b/xen/common/tmem_control.c
@@ -274,13 +274,6 @@ static int __tmemc_set_var(struct client *client, uint32_t
subop, uint32_t arg1)
atomic_add(client->weight,&tmem_global.client_weight_total);
break;
case XEN_SYSCTL_TMEM_OP_SET_COMPRESS:
- if ( tmem_dedup_enabled() )
- {
- tmem_client_warn("tmem: compression %s for all %ss, cannot be
changed when tmem_dedup is enabled\n",
- tmem_compression_enabled() ? "enabled" :
"disabled",
- tmem_client_str);
- return -1;
- }
client->compress = arg1 ? 1 : 0;
tmem_client_info("tmem: compression %s for %s=%d\n",
arg1 ? "enabled" : "disabled",tmem_cli_id_str,cli_id);
diff --git a/xen/common/tmem_xen.c b/xen/common/tmem_xen.c
index 71cb7d5..84ae7fd 100644
--- a/xen/common/tmem_xen.c
+++ b/xen/common/tmem_xen.c
@@ -20,12 +20,6 @@ boolean_param("tmem", opt_tmem);
bool_t __read_mostly opt_tmem_compress = 0;
boolean_param("tmem_compress", opt_tmem_compress);
-bool_t __read_mostly opt_tmem_dedup = 0;
-boolean_param("tmem_dedup", opt_tmem_dedup);
-
-bool_t __read_mostly opt_tmem_tze = 0;
-boolean_param("tmem_tze", opt_tmem_tze);
-
bool_t __read_mostly opt_tmem_shared_auth = 0;
boolean_param("tmem_shared_auth", opt_tmem_shared_auth);
@@ -216,28 +210,6 @@ int tmem_decompress_to_client(xen_pfn_t cmfn, void
*tmem_va,
return 1;
}
-int tmem_copy_tze_to_client(xen_pfn_t cmfn, void *tmem_va,
- pagesize_t len)
-{
- void *cli_va;
- unsigned long cli_mfn;
- struct page_info *cli_pfp = NULL;
-
- ASSERT(!(len & (sizeof(uint64_t)-1)));
- ASSERT(len <= PAGE_SIZE);
- ASSERT(len > 0 || tmem_va == NULL);
- cli_va = cli_get_page(cmfn, &cli_mfn, &cli_pfp, 1);
- if ( cli_va == NULL )
- return -EFAULT;
- if ( len > 0 )
- memcpy((char *)cli_va,(char *)tmem_va,len);
- if ( len < PAGE_SIZE )
- memset((char *)cli_va+len,0,PAGE_SIZE-len);
- cli_put_page(cli_va, cli_pfp, cli_mfn, 1);
- smp_mb();
- return 1;
-}
-
/****************** XEN-SPECIFIC HOST INITIALIZATION ********************/
static int dstmem_order, workmem_order;
diff --git a/xen/include/xen/tmem_xen.h b/xen/include/xen/tmem_xen.h
index 86a5b24..1d31de8 100644
--- a/xen/include/xen/tmem_xen.h
+++ b/xen/include/xen/tmem_xen.h
@@ -41,23 +41,6 @@ static inline bool_t tmem_compression_enabled(void)
return opt_tmem_compress;
}
-extern bool_t opt_tmem_dedup;
-static inline bool_t tmem_dedup_enabled(void)
-{
- return opt_tmem_dedup;
-}
-
-extern bool_t opt_tmem_tze;
-static inline bool_t tmem_tze_enabled(void)
-{
- return opt_tmem_tze;
-}
-
-static inline void tmem_tze_disable(void)
-{
- opt_tmem_tze = 0;
-}
-
extern bool_t opt_tmem_shared_auth;
static inline bool_t tmem_shared_auth(void)
{
@@ -192,103 +175,6 @@ static inline struct client
*tmem_client_from_cli_id(domid_t cli_id)
return c;
}
-static inline uint8_t tmem_get_first_byte(struct page_info *pfp)
-{
- const uint8_t *p = __map_domain_page(pfp);
- uint8_t byte = p[0];
-
- unmap_domain_page(p);
-
- return byte;
-}
-
-static inline int tmem_page_cmp(struct page_info *pfp1, struct page_info *pfp2)
-{
- const uint64_t *p1 = __map_domain_page(pfp1);
- const uint64_t *p2 = __map_domain_page(pfp2);
- int rc = memcmp(p1, p2, PAGE_SIZE);
-
- unmap_domain_page(p2);
- unmap_domain_page(p1);
-
- return rc;
-}
-
-static inline int tmem_pcd_cmp(void *va1, pagesize_t len1, void *va2,
pagesize_t len2)
-{
- const char *p1 = (char *)va1;
- const char *p2 = (char *)va2;
- pagesize_t i;
-
- ASSERT(len1 <= PAGE_SIZE);
- ASSERT(len2 <= PAGE_SIZE);
- if ( len1 < len2 )
- return -1;
- if ( len1 > len2 )
- return 1;
- ASSERT(len1 == len2);
- for ( i = len2; i && *p1 == *p2; i--, p1++, p2++ );
- if ( !i )
- return 0;
- if ( *p1 < *p2 )
- return -1;
- return 1;
-}
-
-static inline int tmem_tze_pfp_cmp(struct page_info *pfp1, pagesize_t pfp_len,
- void *tva, const pagesize_t tze_len)
-{
- const uint64_t *p1 = __map_domain_page(pfp1);
- const uint64_t *p2 = tze_len == PAGE_SIZE ?
- __map_domain_page((struct page_info *)tva) : tva;
- int rc;
-
- ASSERT(pfp_len <= PAGE_SIZE);
- ASSERT(!(pfp_len & (sizeof(uint64_t)-1)));
- ASSERT(tze_len <= PAGE_SIZE);
- ASSERT(!(tze_len & (sizeof(uint64_t)-1)));
- if ( pfp_len < tze_len )
- rc = -1;
- else if ( pfp_len > tze_len )
- rc = 1;
- else
- rc = memcmp(p1, p2, tze_len);
-
- if ( tze_len == PAGE_SIZE )
- unmap_domain_page(p2);
- unmap_domain_page(p1);
-
- return rc;
-}
-
-/* return the size of the data in the pfp, ignoring trailing zeroes and
- * rounded up to the nearest multiple of 8 */
-static inline pagesize_t tmem_tze_pfp_scan(struct page_info *pfp)
-{
- const uint64_t *const page = __map_domain_page(pfp);
- const uint64_t *p = page;
- pagesize_t bytecount = PAGE_SIZE;
- pagesize_t len = PAGE_SIZE/sizeof(uint64_t);
-
- p += len;
- while ( len-- && !*--p )
- bytecount -= sizeof(uint64_t);
-
- unmap_domain_page(page);
-
- return bytecount;
-}
-
-static inline void tmem_tze_copy_from_pfp(void *tva, struct page_info *pfp,
pagesize_t len)
-{
- const uint64_t *p = __map_domain_page(pfp);
-
- ASSERT(!(len & (sizeof(uint64_t)-1)));
- memcpy(tva, p, len);
-
- unmap_domain_page(p);
-}
-
/* these typedefs are in the public/tmem.h interface
typedef XEN_GUEST_HANDLE(void) cli_mfn_t;
typedef XEN_GUEST_HANDLE(char) cli_va_t;
@@ -336,7 +222,6 @@ int tmem_compress_from_client(xen_pfn_t, void **, size_t *,
int tmem_copy_from_client(struct page_info *, xen_pfn_t, tmem_cli_va_param_t);
int tmem_copy_to_client(xen_pfn_t, struct page_info *, tmem_cli_va_param_t);
-extern int tmem_copy_tze_to_client(xen_pfn_t cmfn, void *tmem_va, pagesize_t
len);
#define tmem_client_err(fmt, args...) printk(XENLOG_G_ERR fmt, ##args)
#define tmem_client_warn(fmt, args...) printk(XENLOG_G_WARNING fmt, ##args)
--
2.4.11
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