UBI: use nicer 64-bit math

Get rid of 'do_div()' and use more user-friendly primitives from 'linux/math64.h'. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>

UBI: use nicer 64-bit math
Get rid of 'do_div()' and use more user-friendly primitives from 'linux/math64.h'. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Artem Bityutskiy
1 parent f429b2ea8e
Showing 5 changed files with 25 additions and 52 deletions Side-by-side Diff
drivers/mtd/ubi/cdev.c
drivers/mtd/ubi/gluebi.c
drivers/mtd/ubi/scan.c
drivers/mtd/ubi/upd.c
drivers/mtd/ubi/vmt.c
@@ -41,8 +41,8 @@
 #include <linux/capability.h>
 #include <linux/uaccess.h>
 #include <linux/compat.h>
+#include <linux/math64.h>
 #include <mtd/ubi-user.h>
-#include <asm/div64.h>
 #include "ubi.h"
  
 /**
@@ -195,7 +195,6 @@
 	int err, lnum, off, len,  tbuf_size;
 	size_t count_save = count;
 	void *tbuf;
-	uint64_t tmp;
  
 	dbg_gen("read %zd bytes from offset %lld of volume %d",
 		count, *offp, vol->vol_id);
  
@@ -225,11 +224,8 @@
 		return -ENOMEM;
  
 	len = count > tbuf_size ? tbuf_size : count;
+	lnum = div_u64_rem(*offp, vol->usable_leb_size, &off);
  
-	tmp = *offp;
-	off = do_div(tmp, vol->usable_leb_size);
-	lnum = tmp;
-
 	do {
 		cond_resched();
  
@@ -279,7 +275,6 @@
 	int lnum, off, len, tbuf_size, err = 0;
 	size_t count_save = count;
 	char *tbuf;
-	uint64_t tmp;
  
 	dbg_gen("requested: write %zd bytes to offset %lld of volume %u",
 		count, *offp, vol->vol_id);
@@ -287,10 +282,7 @@
 	if (vol->vol_type == UBI_STATIC_VOLUME)
 		return -EROFS;
  
-	tmp = *offp;
-	off = do_div(tmp, vol->usable_leb_size);
-	lnum = tmp;
-
+	lnum = div_u64_rem(*offp, vol->usable_leb_size, &off);
 	if (off & (ubi->min_io_size - 1)) {
 		dbg_err("unaligned position");
 		return -EINVAL;
@@ -882,7 +874,6 @@
 	case UBI_IOCRSVOL:
 	{
 		int pebs;
-		uint64_t tmp;
 		struct ubi_rsvol_req req;
  
 		dbg_gen("re-size volume");
@@ -902,9 +893,8 @@
 			break;
 		}
  
-		tmp = req.bytes;
-		pebs = !!do_div(tmp, desc->vol->usable_leb_size);
-		pebs += tmp;
+		pebs = div_u64(req.bytes + desc->vol->usable_leb_size - 1,
+			       desc->vol->usable_leb_size);
  
 		mutex_lock(&ubi->volumes_mutex);
 		err = ubi_resize_volume(desc, pebs);
@@ -28,7 +28,7 @@
  * eraseblock size is equivalent to the logical eraseblock size of the volume.
  */
  
-#include <asm/div64.h>
+#include <linux/math64.h>
 #include "ubi.h"
  
 /**
@@ -109,7 +109,6 @@
 	int err = 0, lnum, offs, total_read;
 	struct ubi_volume *vol;
 	struct ubi_device *ubi;
-	uint64_t tmp = from;
  
 	dbg_gen("read %zd bytes from offset %lld", len, from);
  
@@ -119,9 +118,7 @@
 	vol = container_of(mtd, struct ubi_volume, gluebi_mtd);
 	ubi = vol->ubi;
  
-	offs = do_div(tmp, mtd->erasesize);
-	lnum = tmp;
-
+	lnum = div_u64_rem(from, mtd->erasesize, &offs);
 	total_read = len;
 	while (total_read) {
 		size_t to_read = mtd->erasesize - offs;
@@ -160,7 +157,6 @@
 	int err = 0, lnum, offs, total_written;
 	struct ubi_volume *vol;
 	struct ubi_device *ubi;
-	uint64_t tmp = to;
  
 	dbg_gen("write %zd bytes to offset %lld", len, to);
  
@@ -173,8 +169,7 @@
 	if (ubi->ro_mode)
 		return -EROFS;
  
-	offs = do_div(tmp, mtd->erasesize);
-	lnum = tmp;
+	lnum = div_u64_rem(to, mtd->erasesize, &offs);
  
 	if (len % mtd->writesize || offs % mtd->writesize)
 		return -EINVAL;
@@ -42,7 +42,7 @@
  
 #include <linux/err.h>
 #include <linux/crc32.h>
-#include <asm/div64.h>
+#include <linux/math64.h>
 #include "ubi.h"
  
 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
@@ -904,10 +904,8 @@
 	dbg_msg("scanning is finished");
  
 	/* Calculate mean erase counter */
-	if (si->ec_count) {
-		do_div(si->ec_sum, si->ec_count);
-		si->mean_ec = si->ec_sum;
-	}
+	if (si->ec_count)
+		si->mean_ec = div_u64(si->ec_sum, si->ec_count);
  
 	if (si->is_empty)
 		ubi_msg("empty MTD device detected");
@@ -40,7 +40,7 @@
  
 #include <linux/err.h>
 #include <linux/uaccess.h>
-#include <asm/div64.h>
+#include <linux/math64.h>
 #include "ubi.h"
  
 /**
@@ -89,7 +89,6 @@
 			       long long bytes)
 {
 	int err;
-	uint64_t tmp;
 	struct ubi_vtbl_record vtbl_rec;
  
 	dbg_gen("clear update marker for volume %d", vol->vol_id);
@@ -101,9 +100,9 @@
  
 	if (vol->vol_type == UBI_STATIC_VOLUME) {
 		vol->corrupted = 0;
-		vol->used_bytes = tmp = bytes;
-		vol->last_eb_bytes = do_div(tmp, vol->usable_leb_size);
-		vol->used_ebs = tmp;
+		vol->used_bytes = bytes;
+		vol->used_ebs = div_u64_rem(bytes, vol->usable_leb_size,
+					    &vol->last_eb_bytes);
 		if (vol->last_eb_bytes)
 			vol->used_ebs += 1;
 		else
@@ -131,7 +130,6 @@
 		     long long bytes)
 {
 	int i, err;
-	uint64_t tmp;
  
 	dbg_gen("start update of volume %d, %llu bytes", vol->vol_id, bytes);
 	ubi_assert(!vol->updating && !vol->changing_leb);
@@ -161,9 +159,8 @@
 	if (!vol->upd_buf)
 		return -ENOMEM;
  
-	tmp = bytes;
-	vol->upd_ebs = !!do_div(tmp, vol->usable_leb_size);
-	vol->upd_ebs += tmp;
+	vol->upd_ebs = div_u64(bytes + vol->usable_leb_size - 1,
+			       vol->usable_leb_size);
 	vol->upd_bytes = bytes;
 	vol->upd_received = 0;
 	return 0;
@@ -282,7 +279,6 @@
 int ubi_more_update_data(struct ubi_device *ubi, struct ubi_volume *vol,
 			 const void __user *buf, int count)
 {
-	uint64_t tmp;
 	int lnum, offs, err = 0, len, to_write = count;
  
 	dbg_gen("write %d of %lld bytes, %lld already passed",
@@ -291,10 +287,7 @@
 	if (ubi->ro_mode)
 		return -EROFS;
  
-	tmp = vol->upd_received;
-	offs = do_div(tmp, vol->usable_leb_size);
-	lnum = tmp;
-
+	lnum = div_u64_rem(vol->upd_received,  vol->usable_leb_size, &offs);
 	if (vol->upd_received + count > vol->upd_bytes)
 		to_write = count = vol->upd_bytes - vol->upd_received;
  
@@ -24,7 +24,7 @@
  */
  
 #include <linux/err.h>
-#include <asm/div64.h>
+#include <linux/math64.h>
 #include "ubi.h"
  
 #ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
@@ -205,7 +205,6 @@
 	int i, err, vol_id = req->vol_id, do_free = 1;
 	struct ubi_volume *vol;
 	struct ubi_vtbl_record vtbl_rec;
-	uint64_t bytes;
 	dev_t dev;
  
 	if (ubi->ro_mode)
@@ -255,10 +254,8 @@
  
 	/* Calculate how many eraseblocks are requested */
 	vol->usable_leb_size = ubi->leb_size - ubi->leb_size % req->alignment;
-	bytes = req->bytes;
-	if (do_div(bytes, vol->usable_leb_size))
-		vol->reserved_pebs = 1;
-	vol->reserved_pebs += bytes;
+	vol->reserved_pebs += div_u64(req->bytes + vol->usable_leb_size - 1,
+				      vol->usable_leb_size);
  
 	/* Reserve physical eraseblocks */
 	if (vol->reserved_pebs > ubi->avail_pebs) {
@@ -301,10 +298,10 @@
 		vol->used_bytes =
 			(long long)vol->used_ebs * vol->usable_leb_size;
 	} else {
-		bytes = vol->used_bytes;
-		vol->last_eb_bytes = do_div(bytes, vol->usable_leb_size);
-		vol->used_ebs = bytes;
-		if (vol->last_eb_bytes)
+		vol->used_ebs = div_u64_rem(vol->used_bytes,
+					    vol->usable_leb_size,
+					    &vol->last_eb_bytes);
+		if (vol->last_eb_bytes != 0)
 			vol->used_ebs += 1;
 		else
 			vol->last_eb_bytes = vol->usable_leb_size;
...	...	@@ -41,8 +41,8 @@
41	41	#include <linux/capability.h>
42	42	#include <linux/uaccess.h>
43	43	#include <linux/compat.h>
	44	+#include <linux/math64.h>
44	45	#include <mtd/ubi-user.h>
45		-#include <asm/div64.h>
46	46	#include "ubi.h"
47	47
48	48	/**
...	...	@@ -195,7 +195,6 @@
195	195	int err, lnum, off, len, tbuf_size;
196	196	size_t count_save = count;
197	197	void *tbuf;
198		- uint64_t tmp;
199	198
200	199	dbg_gen("read %zd bytes from offset %lld of volume %d",
201	200	count, *offp, vol->vol_id);
202	201
...	...	@@ -225,11 +224,8 @@
225	224	return -ENOMEM;
226	225
227	226	len = count > tbuf_size ? tbuf_size : count;
	227	+ lnum = div_u64_rem(*offp, vol->usable_leb_size, &off);
228	228
229		- tmp = *offp;
230		- off = do_div(tmp, vol->usable_leb_size);
231		- lnum = tmp;
232		-
233	229	do {
234	230	cond_resched();
235	231
...	...	@@ -279,7 +275,6 @@
279	275	int lnum, off, len, tbuf_size, err = 0;
280	276	size_t count_save = count;
281	277	char *tbuf;
282		- uint64_t tmp;
283	278
284	279	dbg_gen("requested: write %zd bytes to offset %lld of volume %u",
285	280	count, *offp, vol->vol_id);
...	...	@@ -287,10 +282,7 @@
287	282	if (vol->vol_type == UBI_STATIC_VOLUME)
288	283	return -EROFS;
289	284
290		- tmp = *offp;
291		- off = do_div(tmp, vol->usable_leb_size);
292		- lnum = tmp;
293		-
	285	+ lnum = div_u64_rem(*offp, vol->usable_leb_size, &off);
294	286	if (off & (ubi->min_io_size - 1)) {
295	287	dbg_err("unaligned position");
296	288	return -EINVAL;
...	...	@@ -882,7 +874,6 @@
882	874	case UBI_IOCRSVOL:
883	875	{
884	876	int pebs;
885		- uint64_t tmp;
886	877	struct ubi_rsvol_req req;
887	878
888	879	dbg_gen("re-size volume");
...	...	@@ -902,9 +893,8 @@
902	893	break;
903	894	}
904	895
905		- tmp = req.bytes;
906		- pebs = !!do_div(tmp, desc->vol->usable_leb_size);
907		- pebs += tmp;
	896	+ pebs = div_u64(req.bytes + desc->vol->usable_leb_size - 1,
	897	+ desc->vol->usable_leb_size);
908	898
909	899	mutex_lock(&ubi->volumes_mutex);
910	900	err = ubi_resize_volume(desc, pebs);
...	...	@@ -28,7 +28,7 @@
28	28	* eraseblock size is equivalent to the logical eraseblock size of the volume.
29	29	*/
30	30
31		-#include <asm/div64.h>
	31	+#include <linux/math64.h>
32	32	#include "ubi.h"
33	33
34	34	/**
...	...	@@ -109,7 +109,6 @@
109	109	int err = 0, lnum, offs, total_read;
110	110	struct ubi_volume *vol;
111	111	struct ubi_device *ubi;
112		- uint64_t tmp = from;
113	112
114	113	dbg_gen("read %zd bytes from offset %lld", len, from);
115	114
...	...	@@ -119,9 +118,7 @@
119	118	vol = container_of(mtd, struct ubi_volume, gluebi_mtd);
120	119	ubi = vol->ubi;
121	120
122		- offs = do_div(tmp, mtd->erasesize);
123		- lnum = tmp;
124		-
	121	+ lnum = div_u64_rem(from, mtd->erasesize, &offs);
125	122	total_read = len;
126	123	while (total_read) {
127	124	size_t to_read = mtd->erasesize - offs;
...	...	@@ -160,7 +157,6 @@
160	157	int err = 0, lnum, offs, total_written;
161	158	struct ubi_volume *vol;
162	159	struct ubi_device *ubi;
163		- uint64_t tmp = to;
164	160
165	161	dbg_gen("write %zd bytes to offset %lld", len, to);
166	162
...	...	@@ -173,8 +169,7 @@
173	169	if (ubi->ro_mode)
174	170	return -EROFS;
175	171
176		- offs = do_div(tmp, mtd->erasesize);
177		- lnum = tmp;
	172	+ lnum = div_u64_rem(to, mtd->erasesize, &offs);
178	173
179	174	if (len % mtd->writesize \|\| offs % mtd->writesize)
180	175	return -EINVAL;
...	...	@@ -42,7 +42,7 @@
42	42
43	43	#include <linux/err.h>
44	44	#include <linux/crc32.h>
45		-#include <asm/div64.h>
	45	+#include <linux/math64.h>
46	46	#include "ubi.h"
47	47
48	48	#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
...	...	@@ -904,10 +904,8 @@
904	904	dbg_msg("scanning is finished");
905	905
906	906	/* Calculate mean erase counter */
907		- if (si->ec_count) {
908		- do_div(si->ec_sum, si->ec_count);
909		- si->mean_ec = si->ec_sum;
910		- }
	907	+ if (si->ec_count)
	908	+ si->mean_ec = div_u64(si->ec_sum, si->ec_count);
911	909
912	910	if (si->is_empty)
913	911	ubi_msg("empty MTD device detected");
...	...	@@ -40,7 +40,7 @@
40	40
41	41	#include <linux/err.h>
42	42	#include <linux/uaccess.h>
43		-#include <asm/div64.h>
	43	+#include <linux/math64.h>
44	44	#include "ubi.h"
45	45
46	46	/**
...	...	@@ -89,7 +89,6 @@
89	89	long long bytes)
90	90	{
91	91	int err;
92		- uint64_t tmp;
93	92	struct ubi_vtbl_record vtbl_rec;
94	93
95	94	dbg_gen("clear update marker for volume %d", vol->vol_id);
...	...	@@ -101,9 +100,9 @@
101	100
102	101	if (vol->vol_type == UBI_STATIC_VOLUME) {
103	102	vol->corrupted = 0;
104		- vol->used_bytes = tmp = bytes;
105		- vol->last_eb_bytes = do_div(tmp, vol->usable_leb_size);
106		- vol->used_ebs = tmp;
	103	+ vol->used_bytes = bytes;
	104	+ vol->used_ebs = div_u64_rem(bytes, vol->usable_leb_size,
	105	+ &vol->last_eb_bytes);
107	106	if (vol->last_eb_bytes)
108	107	vol->used_ebs += 1;
109	108	else
...	...	@@ -131,7 +130,6 @@
131	130	long long bytes)
132	131	{
133	132	int i, err;
134		- uint64_t tmp;
135	133
136	134	dbg_gen("start update of volume %d, %llu bytes", vol->vol_id, bytes);
137	135	ubi_assert(!vol->updating && !vol->changing_leb);
...	...	@@ -161,9 +159,8 @@
161	159	if (!vol->upd_buf)
162	160	return -ENOMEM;
163	161
164		- tmp = bytes;
165		- vol->upd_ebs = !!do_div(tmp, vol->usable_leb_size);
166		- vol->upd_ebs += tmp;
	162	+ vol->upd_ebs = div_u64(bytes + vol->usable_leb_size - 1,
	163	+ vol->usable_leb_size);
167	164	vol->upd_bytes = bytes;
168	165	vol->upd_received = 0;
169	166	return 0;
...	...	@@ -282,7 +279,6 @@
282	279	int ubi_more_update_data(struct ubi_device ubi, struct ubi_volume vol,
283	280	const void __user *buf, int count)
284	281	{
285		- uint64_t tmp;
286	282	int lnum, offs, err = 0, len, to_write = count;
287	283
288	284	dbg_gen("write %d of %lld bytes, %lld already passed",
...	...	@@ -291,10 +287,7 @@
291	287	if (ubi->ro_mode)
292	288	return -EROFS;
293	289
294		- tmp = vol->upd_received;
295		- offs = do_div(tmp, vol->usable_leb_size);
296		- lnum = tmp;
297		-
	290	+ lnum = div_u64_rem(vol->upd_received, vol->usable_leb_size, &offs);
298	291	if (vol->upd_received + count > vol->upd_bytes)
299	292	to_write = count = vol->upd_bytes - vol->upd_received;
300	293
...	...	@@ -24,7 +24,7 @@
24	24	*/
25	25
26	26	#include <linux/err.h>
27		-#include <asm/div64.h>
	27	+#include <linux/math64.h>
28	28	#include "ubi.h"
29	29
30	30	#ifdef CONFIG_MTD_UBI_DEBUG_PARANOID
...	...	@@ -205,7 +205,6 @@
205	205	int i, err, vol_id = req->vol_id, do_free = 1;
206	206	struct ubi_volume *vol;
207	207	struct ubi_vtbl_record vtbl_rec;
208		- uint64_t bytes;
209	208	dev_t dev;
210	209
211	210	if (ubi->ro_mode)
...	...	@@ -255,10 +254,8 @@
255	254
256	255	/* Calculate how many eraseblocks are requested */
257	256	vol->usable_leb_size = ubi->leb_size - ubi->leb_size % req->alignment;
258		- bytes = req->bytes;
259		- if (do_div(bytes, vol->usable_leb_size))
260		- vol->reserved_pebs = 1;
261		- vol->reserved_pebs += bytes;
	257	+ vol->reserved_pebs += div_u64(req->bytes + vol->usable_leb_size - 1,
	258	+ vol->usable_leb_size);
262	259
263	260	/* Reserve physical eraseblocks */
264	261	if (vol->reserved_pebs > ubi->avail_pebs) {
...	...	@@ -301,10 +298,10 @@
301	298	vol->used_bytes =
302	299	(long long)vol->used_ebs * vol->usable_leb_size;
303	300	} else {
304		- bytes = vol->used_bytes;
305		- vol->last_eb_bytes = do_div(bytes, vol->usable_leb_size);
306		- vol->used_ebs = bytes;
307		- if (vol->last_eb_bytes)
	301	+ vol->used_ebs = div_u64_rem(vol->used_bytes,
	302	+ vol->usable_leb_size,
	303	+ &vol->last_eb_bytes);
	304	+ if (vol->last_eb_bytes != 0)
308	305	vol->used_ebs += 1;
309	306	else
310	307	vol->last_eb_bytes = vol->usable_leb_size;