mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macros

PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time
ago with promise that one day it will be possible to implement page
cache with bigger chunks than PAGE_SIZE.

This promise never materialized.  And unlikely will.

We have many places where PAGE_CACHE_SIZE assumed to be equal to
PAGE_SIZE.  And it's constant source of confusion on whether
PAGE_CACHE_* or PAGE_* constant should be used in a particular case,
especially on the border between fs and mm.

Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much
breakage to be doable.

Let's stop pretending that pages in page cache are special.  They are
not.

The changes are pretty straight-forward:

 - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>;

 - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN};

 - page_cache_get() -> get_page();

 - page_cache_release() -> put_page();

This patch contains automated changes generated with coccinelle using
script below.  For some reason, coccinelle doesn't patch header files.
I've called spatch for them manually.

The only adjustment after coccinelle is revert of changes to
PAGE_CAHCE_ALIGN definition: we are going to drop it later.

There are few places in the code where coccinelle didn't reach.  I'll
fix them manually in a separate patch.  Comments and documentation also
will be addressed with the separate patch.

virtual patch

@@
expression E;
@@
- E << (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
expression E;
@@
- E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT)
+ E

@@
@@
- PAGE_CACHE_SHIFT
+ PAGE_SHIFT

@@
@@
- PAGE_CACHE_SIZE
+ PAGE_SIZE

@@
@@
- PAGE_CACHE_MASK
+ PAGE_MASK

@@
expression E;
@@
- PAGE_CACHE_ALIGN(E)
+ PAGE_ALIGN(E)

@@
expression E;
@@
- page_cache_get(E)
+ get_page(E)

@@
expression E;
@@
- page_cache_release(E)
+ put_page(E)

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

14 files changed, 42 insertions, 42 deletions

diff --git a/drivers/staging/lustre/lnet/klnds/socklnd/socklnd_lib.c b/drivers/staging/lustre/lnet/klnds/socklnd/socklnd_lib.c
index 3e1f24e77f644..d4ce06d0aeebb 100644
--- a/drivers/staging/lustre/lnet/klnds/socklnd/socklnd_lib.c
+++ b/drivers/staging/lustre/lnet/klnds/socklnd/socklnd_lib.c
@@ -291,7 +291,7 @@ ksocknal_lib_kiov_vmap(lnet_kiov_t *kiov, int niov,
 
 	for (nob = i = 0; i < niov; i++) {
 		if ((kiov[i].kiov_offset && i > 0) ||
-		    (kiov[i].kiov_offset + kiov[i].kiov_len != PAGE_CACHE_SIZE && i < niov - 1))
+		    (kiov[i].kiov_offset + kiov[i].kiov_len != PAGE_SIZE && i < niov - 1))
 			return NULL;
 
 		pages[i] = kiov[i].kiov_page;
diff --git a/drivers/staging/lustre/lnet/libcfs/debug.c b/drivers/staging/lustre/lnet/libcfs/debug.c
index c90e5102fe065..c3d628bac5b81 100644
--- a/drivers/staging/lustre/lnet/libcfs/debug.c
+++ b/drivers/staging/lustre/lnet/libcfs/debug.c
@@ -517,7 +517,7 @@ int libcfs_debug_init(unsigned long bufsize)
 		max = TCD_MAX_PAGES;
 	} else {
 		max = max / num_possible_cpus();
-		max <<= (20 - PAGE_CACHE_SHIFT);
+		max <<= (20 - PAGE_SHIFT);
 	}
 	rc = cfs_tracefile_init(max);
 
diff --git a/drivers/staging/lustre/lnet/libcfs/tracefile.c b/drivers/staging/lustre/lnet/libcfs/tracefile.c
index ec3bc04bd89f2..244eb89eef689 100644
--- a/drivers/staging/lustre/lnet/libcfs/tracefile.c
+++ b/drivers/staging/lustre/lnet/libcfs/tracefile.c
@@ -182,7 +182,7 @@ cfs_trace_get_tage_try(struct cfs_trace_cpu_data *tcd, unsigned long len)
 	if (tcd->tcd_cur_pages > 0) {
 		__LASSERT(!list_empty(&tcd->tcd_pages));
 		tage = cfs_tage_from_list(tcd->tcd_pages.prev);
-		if (tage->used + len <= PAGE_CACHE_SIZE)
+		if (tage->used + len <= PAGE_SIZE)
 			return tage;
 	}
 
@@ -260,7 +260,7 @@ static struct cfs_trace_page *cfs_trace_get_tage(struct cfs_trace_cpu_data *tcd,
 	 * from here: this will lead to infinite recursion.
 	 */
 
-	if (len > PAGE_CACHE_SIZE) {
+	if (len > PAGE_SIZE) {
 		pr_err("cowardly refusing to write %lu bytes in a page\n", len);
 		return NULL;
 	}
@@ -349,7 +349,7 @@ int libcfs_debug_vmsg2(struct libcfs_debug_msg_data *msgdata,
 	for (i = 0; i < 2; i++) {
 		tage = cfs_trace_get_tage(tcd, needed + known_size + 1);
 		if (!tage) {
-			if (needed + known_size > PAGE_CACHE_SIZE)
+			if (needed + known_size > PAGE_SIZE)
 				mask |= D_ERROR;
 
 			cfs_trace_put_tcd(tcd);
@@ -360,7 +360,7 @@ int libcfs_debug_vmsg2(struct libcfs_debug_msg_data *msgdata,
 		string_buf = (char *)page_address(tage->page) +
 					tage->used + known_size;
 
-		max_nob = PAGE_CACHE_SIZE - tage->used - known_size;
+		max_nob = PAGE_SIZE - tage->used - known_size;
 		if (max_nob <= 0) {
 			printk(KERN_EMERG "negative max_nob: %d\n",
 			       max_nob);
@@ -424,7 +424,7 @@ int libcfs_debug_vmsg2(struct libcfs_debug_msg_data *msgdata,
 	__LASSERT(debug_buf == string_buf);
 
 	tage->used += needed;
-	__LASSERT(tage->used <= PAGE_CACHE_SIZE);
+	__LASSERT(tage->used <= PAGE_SIZE);
 
 console:
 	if ((mask & libcfs_printk) == 0) {
@@ -835,7 +835,7 @@ EXPORT_SYMBOL(cfs_trace_copyout_string);
 
 int cfs_trace_allocate_string_buffer(char **str, int nob)
 {
-	if (nob > 2 * PAGE_CACHE_SIZE)	    /* string must be "sensible" */
+	if (nob > 2 * PAGE_SIZE)	    /* string must be "sensible" */
 		return -EINVAL;
 
 	*str = kmalloc(nob, GFP_KERNEL | __GFP_ZERO);
@@ -951,7 +951,7 @@ int cfs_trace_set_debug_mb(int mb)
 	}
 
 	mb /= num_possible_cpus();
-	pages = mb << (20 - PAGE_CACHE_SHIFT);
+	pages = mb << (20 - PAGE_SHIFT);
 
 	cfs_tracefile_write_lock();
 
@@ -977,7 +977,7 @@ int cfs_trace_get_debug_mb(void)
 
 	cfs_tracefile_read_unlock();
 
-	return (total_pages >> (20 - PAGE_CACHE_SHIFT)) + 1;
+	return (total_pages >> (20 - PAGE_SHIFT)) + 1;
 }
 
 static int tracefiled(void *arg)
diff --git a/drivers/staging/lustre/lnet/libcfs/tracefile.h b/drivers/staging/lustre/lnet/libcfs/tracefile.h
index 4c77f9044dd35..ac84e7f4c859e 100644
--- a/drivers/staging/lustre/lnet/libcfs/tracefile.h
+++ b/drivers/staging/lustre/lnet/libcfs/tracefile.h
@@ -87,7 +87,7 @@ void libcfs_unregister_panic_notifier(void);
 extern int  libcfs_panic_in_progress;
 int cfs_trace_max_debug_mb(void);
 
-#define TCD_MAX_PAGES (5 << (20 - PAGE_CACHE_SHIFT))
+#define TCD_MAX_PAGES (5 << (20 - PAGE_SHIFT))
 #define TCD_STOCK_PAGES (TCD_MAX_PAGES)
 #define CFS_TRACEFILE_SIZE (500 << 20)
 
@@ -96,7 +96,7 @@ int cfs_trace_max_debug_mb(void);
 /*
  * Private declare for tracefile
  */
-#define TCD_MAX_PAGES (5 << (20 - PAGE_CACHE_SHIFT))
+#define TCD_MAX_PAGES (5 << (20 - PAGE_SHIFT))
 #define TCD_STOCK_PAGES (TCD_MAX_PAGES)
 
 #define CFS_TRACEFILE_SIZE (500 << 20)
@@ -257,7 +257,7 @@ do {								    \
 do {								    \
 	__LASSERT(tage);					\
 	__LASSERT(tage->page);				  \
-	__LASSERT(tage->used <= PAGE_CACHE_SIZE);			 \
+	__LASSERT(tage->used <= PAGE_SIZE);			 \
 	__LASSERT(page_count(tage->page) > 0);		      \
 } while (0)
 
diff --git a/drivers/staging/lustre/lnet/lnet/lib-md.c b/drivers/staging/lustre/lnet/lnet/lib-md.c
index c74514f99f90d..75d31217bf924 100644
--- a/drivers/staging/lustre/lnet/lnet/lib-md.c
+++ b/drivers/staging/lustre/lnet/lnet/lib-md.c
@@ -139,7 +139,7 @@ lnet_md_build(lnet_libmd_t *lmd, lnet_md_t *umd, int unlink)
 		for (i = 0; i < (int)niov; i++) {
 			/* We take the page pointer on trust */
 			if (lmd->md_iov.kiov[i].kiov_offset +
-			    lmd->md_iov.kiov[i].kiov_len > PAGE_CACHE_SIZE)
+			    lmd->md_iov.kiov[i].kiov_len > PAGE_SIZE)
 				return -EINVAL; /* invalid length */
 
 			total_length += lmd->md_iov.kiov[i].kiov_len;
diff --git a/drivers/staging/lustre/lnet/lnet/lib-move.c b/drivers/staging/lustre/lnet/lnet/lib-move.c
index 0009a8de77d57..f19aa9320e340 100644
--- a/drivers/staging/lustre/lnet/lnet/lib-move.c
+++ b/drivers/staging/lustre/lnet/lnet/lib-move.c
@@ -549,12 +549,12 @@ lnet_extract_kiov(int dst_niov, lnet_kiov_t *dst,
 		if (len <= frag_len) {
 			dst->kiov_len = len;
 			LASSERT(dst->kiov_offset + dst->kiov_len
-					<= PAGE_CACHE_SIZE);
+					<= PAGE_SIZE);
 			return niov;
 		}
 
 		dst->kiov_len = frag_len;
-		LASSERT(dst->kiov_offset + dst->kiov_len <= PAGE_CACHE_SIZE);
+		LASSERT(dst->kiov_offset + dst->kiov_len <= PAGE_SIZE);
 
 		len -= frag_len;
 		dst++;
@@ -887,7 +887,7 @@ lnet_msg2bufpool(lnet_msg_t *msg)
 	rbp = &the_lnet.ln_rtrpools[cpt][0];
 
 	LASSERT(msg->msg_len <= LNET_MTU);
-	while (msg->msg_len > (unsigned int)rbp->rbp_npages * PAGE_CACHE_SIZE) {
+	while (msg->msg_len > (unsigned int)rbp->rbp_npages * PAGE_SIZE) {
 		rbp++;
 		LASSERT(rbp < &the_lnet.ln_rtrpools[cpt][LNET_NRBPOOLS]);
 	}
diff --git a/drivers/staging/lustre/lnet/lnet/lib-socket.c b/drivers/staging/lustre/lnet/lnet/lib-socket.c
index cc0c2753dd63f..891fd59401d7e 100644
--- a/drivers/staging/lustre/lnet/lnet/lib-socket.c
+++ b/drivers/staging/lustre/lnet/lnet/lib-socket.c
@@ -166,9 +166,9 @@ lnet_ipif_enumerate(char ***namesp)
 	nalloc = 16;	/* first guess at max interfaces */
 	toobig = 0;
 	for (;;) {
-		if (nalloc * sizeof(*ifr) > PAGE_CACHE_SIZE) {
+		if (nalloc * sizeof(*ifr) > PAGE_SIZE) {
 			toobig = 1;
-			nalloc = PAGE_CACHE_SIZE / sizeof(*ifr);
+			nalloc = PAGE_SIZE / sizeof(*ifr);
 			CWARN("Too many interfaces: only enumerating first %d\n",
 			      nalloc);
 		}
diff --git a/drivers/staging/lustre/lnet/lnet/router.c b/drivers/staging/lustre/lnet/lnet/router.c
index 61459cf9d58fa..b01dc424c514e 100644
--- a/drivers/staging/lustre/lnet/lnet/router.c
+++ b/drivers/staging/lustre/lnet/lnet/router.c
@@ -27,8 +27,8 @@
 #define LNET_NRB_SMALL_PAGES	1
 #define LNET_NRB_LARGE_MIN	256	/* min value for each CPT */
 #define LNET_NRB_LARGE		(LNET_NRB_LARGE_MIN * 4)
-#define LNET_NRB_LARGE_PAGES   ((LNET_MTU + PAGE_CACHE_SIZE - 1) >> \
-				 PAGE_CACHE_SHIFT)
+#define LNET_NRB_LARGE_PAGES   ((LNET_MTU + PAGE_SIZE - 1) >> \
+				 PAGE_SHIFT)
 
 static char *forwarding = "";
 module_param(forwarding, charp, 0444);
@@ -1338,7 +1338,7 @@ lnet_new_rtrbuf(lnet_rtrbufpool_t *rbp, int cpt)
 			return NULL;
 		}
 
-		rb->rb_kiov[i].kiov_len = PAGE_CACHE_SIZE;
+		rb->rb_kiov[i].kiov_len = PAGE_SIZE;
 		rb->rb_kiov[i].kiov_offset = 0;
 		rb->rb_kiov[i].kiov_page = page;
 	}
diff --git a/drivers/staging/lustre/lnet/selftest/brw_test.c b/drivers/staging/lustre/lnet/selftest/brw_test.c
index eebc92412061f..dcb6e506f592a 100644
--- a/drivers/staging/lustre/lnet/selftest/brw_test.c
+++ b/drivers/staging/lustre/lnet/selftest/brw_test.c
@@ -90,7 +90,7 @@ brw_client_init(sfw_test_instance_t *tsi)
 		 * NB: this is not going to work for variable page size,
 		 * but we have to keep it for compatibility
 		 */
-		len = npg * PAGE_CACHE_SIZE;
+		len = npg * PAGE_SIZE;
 
 	} else {
 		test_bulk_req_v1_t *breq = &tsi->tsi_u.bulk_v1;
@@ -104,7 +104,7 @@ brw_client_init(sfw_test_instance_t *tsi)
 		opc = breq->blk_opc;
 		flags = breq->blk_flags;
 		len = breq->blk_len;
-		npg = (len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+		npg = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 	}
 
 	if (npg > LNET_MAX_IOV || npg <= 0)
@@ -167,13 +167,13 @@ brw_fill_page(struct page *pg, int pattern, __u64 magic)
 
 	if (pattern == LST_BRW_CHECK_SIMPLE) {
 		memcpy(addr, &magic, BRW_MSIZE);
-		addr += PAGE_CACHE_SIZE - BRW_MSIZE;
+		addr += PAGE_SIZE - BRW_MSIZE;
 		memcpy(addr, &magic, BRW_MSIZE);
 		return;
 	}
 
 	if (pattern == LST_BRW_CHECK_FULL) {
-		for (i = 0; i < PAGE_CACHE_SIZE / BRW_MSIZE; i++)
+		for (i = 0; i < PAGE_SIZE / BRW_MSIZE; i++)
 			memcpy(addr + i * BRW_MSIZE, &magic, BRW_MSIZE);
 		return;
 	}
@@ -198,7 +198,7 @@ brw_check_page(struct page *pg, int pattern, __u64 magic)
 		if (data != magic)
 			goto bad_data;
 
-		addr += PAGE_CACHE_SIZE - BRW_MSIZE;
+		addr += PAGE_SIZE - BRW_MSIZE;
 		data = *((__u64 *)addr);
 		if (data != magic)
 			goto bad_data;
@@ -207,7 +207,7 @@ brw_check_page(struct page *pg, int pattern, __u64 magic)
 	}
 
 	if (pattern == LST_BRW_CHECK_FULL) {
-		for (i = 0; i < PAGE_CACHE_SIZE / BRW_MSIZE; i++) {
+		for (i = 0; i < PAGE_SIZE / BRW_MSIZE; i++) {
 			data = *(((__u64 *)addr) + i);
 			if (data != magic)
 				goto bad_data;
@@ -278,7 +278,7 @@ brw_client_prep_rpc(sfw_test_unit_t *tsu,
 		opc = breq->blk_opc;
 		flags = breq->blk_flags;
 		npg = breq->blk_npg;
-		len = npg * PAGE_CACHE_SIZE;
+		len = npg * PAGE_SIZE;
 
 	} else {
 		test_bulk_req_v1_t *breq = &tsi->tsi_u.bulk_v1;
@@ -292,7 +292,7 @@ brw_client_prep_rpc(sfw_test_unit_t *tsu,
 		opc = breq->blk_opc;
 		flags = breq->blk_flags;
 		len = breq->blk_len;
-		npg = (len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+		npg = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 	}
 
 	rc = sfw_create_test_rpc(tsu, dest, sn->sn_features, npg, len, &rpc);
@@ -463,10 +463,10 @@ brw_server_handle(struct srpc_server_rpc *rpc)
 			reply->brw_status = EINVAL;
 			return 0;
 		}
-		npg = reqst->brw_len >> PAGE_CACHE_SHIFT;
+		npg = reqst->brw_len >> PAGE_SHIFT;
 
 	} else {
-		npg = (reqst->brw_len + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+		npg = (reqst->brw_len + PAGE_SIZE - 1) >> PAGE_SHIFT;
 	}
 
 	replymsg->msg_ses_feats = reqstmsg->msg_ses_feats;
diff --git a/drivers/staging/lustre/lnet/selftest/conctl.c b/drivers/staging/lustre/lnet/selftest/conctl.c
index 5c7cb72eac9a5..79ee6c0bf7c14 100644
--- a/drivers/staging/lustre/lnet/selftest/conctl.c
+++ b/drivers/staging/lustre/lnet/selftest/conctl.c
@@ -743,7 +743,7 @@ static int lst_test_add_ioctl(lstio_test_args_t *args)
 	if (args->lstio_tes_param &&
 	    (args->lstio_tes_param_len <= 0 ||
 	     args->lstio_tes_param_len >
-	     PAGE_CACHE_SIZE - sizeof(lstcon_test_t)))
+	     PAGE_SIZE - sizeof(lstcon_test_t)))
 		return -EINVAL;
 
 	LIBCFS_ALLOC(batch_name, args->lstio_tes_bat_nmlen + 1);
@@ -819,7 +819,7 @@ lstcon_ioctl_entry(unsigned int cmd, struct libcfs_ioctl_hdr *hdr)
 
 	opc = data->ioc_u32[0];
 
-	if (data->ioc_plen1 > PAGE_CACHE_SIZE)
+	if (data->ioc_plen1 > PAGE_SIZE)
 		return -EINVAL;
 
 	LIBCFS_ALLOC(buf, data->ioc_plen1);
diff --git a/drivers/staging/lustre/lnet/selftest/conrpc.c b/drivers/staging/lustre/lnet/selftest/conrpc.c
index bcd78888f9cc3..35a227d0c6577 100644
--- a/drivers/staging/lustre/lnet/selftest/conrpc.c
+++ b/drivers/staging/lustre/lnet/selftest/conrpc.c
@@ -786,8 +786,8 @@ lstcon_bulkrpc_v0_prep(lst_test_bulk_param_t *param, srpc_test_reqst_t *req)
 	test_bulk_req_t *brq = &req->tsr_u.bulk_v0;
 
 	brq->blk_opc = param->blk_opc;
-	brq->blk_npg = (param->blk_size + PAGE_CACHE_SIZE - 1) /
-			PAGE_CACHE_SIZE;
+	brq->blk_npg = (param->blk_size + PAGE_SIZE - 1) /
+			PAGE_SIZE;
 	brq->blk_flags = param->blk_flags;
 
 	return 0;
@@ -822,7 +822,7 @@ lstcon_testrpc_prep(lstcon_node_t *nd, int transop, unsigned feats,
 	if (transop == LST_TRANS_TSBCLIADD) {
 		npg = sfw_id_pages(test->tes_span);
 		nob = !(feats & LST_FEAT_BULK_LEN) ?
-		      npg * PAGE_CACHE_SIZE :
+		      npg * PAGE_SIZE :
 		      sizeof(lnet_process_id_packed_t) * test->tes_span;
 	}
 
@@ -851,8 +851,8 @@ lstcon_testrpc_prep(lstcon_node_t *nd, int transop, unsigned feats,
 			LASSERT(nob > 0);
 
 			len = !(feats & LST_FEAT_BULK_LEN) ?
-			      PAGE_CACHE_SIZE :
-			      min_t(int, nob, PAGE_CACHE_SIZE);
+			      PAGE_SIZE :
+			      min_t(int, nob, PAGE_SIZE);
 			nob -= len;
 
 			bulk->bk_iovs[i].kiov_offset = 0;
diff --git a/drivers/staging/lustre/lnet/selftest/framework.c b/drivers/staging/lustre/lnet/selftest/framework.c
index 926c3970c498e..e2c5323993668 100644
--- a/drivers/staging/lustre/lnet/selftest/framework.c
+++ b/drivers/staging/lustre/lnet/selftest/framework.c
@@ -1161,7 +1161,7 @@ sfw_add_test(struct srpc_server_rpc *rpc)
 		int len;
 
 		if (!(sn->sn_features & LST_FEAT_BULK_LEN)) {
-			len = npg * PAGE_CACHE_SIZE;
+			len = npg * PAGE_SIZE;
 
 		} else {
 			len = sizeof(lnet_process_id_packed_t) *
diff --git a/drivers/staging/lustre/lnet/selftest/rpc.c b/drivers/staging/lustre/lnet/selftest/rpc.c
index 69be7d6f48fa9..7d7748d963326 100644
--- a/drivers/staging/lustre/lnet/selftest/rpc.c
+++ b/drivers/staging/lustre/lnet/selftest/rpc.c
@@ -90,7 +90,7 @@ void srpc_set_counters(const srpc_counters_t *cnt)
 static int
 srpc_add_bulk_page(srpc_bulk_t *bk, struct page *pg, int i, int nob)
 {
-	nob = min_t(int, nob, PAGE_CACHE_SIZE);
+	nob = min_t(int, nob, PAGE_SIZE);
 
 	LASSERT(nob > 0);
 	LASSERT(i >= 0 && i < bk->bk_niov);
diff --git a/drivers/staging/lustre/lnet/selftest/selftest.h b/drivers/staging/lustre/lnet/selftest/selftest.h
index 288522d4d7b94..5321ddec95800 100644
--- a/drivers/staging/lustre/lnet/selftest/selftest.h
+++ b/drivers/staging/lustre/lnet/selftest/selftest.h
@@ -393,7 +393,7 @@ typedef struct sfw_test_instance {
 /* XXX: trailing (PAGE_CACHE_SIZE % sizeof(lnet_process_id_t)) bytes at
  * the end of pages are not used */
 #define SFW_MAX_CONCUR	   LST_MAX_CONCUR
-#define SFW_ID_PER_PAGE    (PAGE_CACHE_SIZE / sizeof(lnet_process_id_packed_t))
+#define SFW_ID_PER_PAGE    (PAGE_SIZE / sizeof(lnet_process_id_packed_t))
 #define SFW_MAX_NDESTS	   (LNET_MAX_IOV * SFW_ID_PER_PAGE)
 #define sfw_id_pages(n)    (((n) + SFW_ID_PER_PAGE - 1) / SFW_ID_PER_PAGE)