UBI: do not use vmalloc on I/O path
Similar reason as in case of the previous patch: it causes
deadlocks if a filesystem with writeback support works on top
of UBI. So pre-allocate needed buffers when attaching MTD device.
We also need mutexes to protect the buffers, but they do not
cause much contantion because they are used in recovery, torture,
and WL copy routines, which are called seldom.
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c
index 8919310..81bb6a3 100644
--- a/drivers/mtd/ubi/eba.c
+++ b/drivers/mtd/ubi/eba.c
@@ -495,16 +495,18 @@
int err, idx = vol_id2idx(ubi, vol_id), new_pnum, data_size, tries = 0;
struct ubi_volume *vol = ubi->volumes[idx];
struct ubi_vid_hdr *vid_hdr;
- unsigned char *new_buf;
vid_hdr = ubi_zalloc_vid_hdr(ubi, GFP_NOFS);
if (!vid_hdr) {
return -ENOMEM;
}
+ mutex_lock(&ubi->buf_mutex);
+
retry:
new_pnum = ubi_wl_get_peb(ubi, UBI_UNKNOWN);
if (new_pnum < 0) {
+ mutex_unlock(&ubi->buf_mutex);
ubi_free_vid_hdr(ubi, vid_hdr);
return new_pnum;
}
@@ -524,31 +526,22 @@
goto write_error;
data_size = offset + len;
- new_buf = vmalloc(data_size);
- if (!new_buf) {
- err = -ENOMEM;
- goto out_put;
- }
- memset(new_buf + offset, 0xFF, len);
+ memset(ubi->peb_buf1 + offset, 0xFF, len);
/* Read everything before the area where the write failure happened */
if (offset > 0) {
- err = ubi_io_read_data(ubi, new_buf, pnum, 0, offset);
- if (err && err != UBI_IO_BITFLIPS) {
- vfree(new_buf);
+ err = ubi_io_read_data(ubi, ubi->peb_buf1, pnum, 0, offset);
+ if (err && err != UBI_IO_BITFLIPS)
goto out_put;
- }
}
- memcpy(new_buf + offset, buf, len);
+ memcpy(ubi->peb_buf1 + offset, buf, len);
- err = ubi_io_write_data(ubi, new_buf, new_pnum, 0, data_size);
- if (err) {
- vfree(new_buf);
+ err = ubi_io_write_data(ubi, ubi->peb_buf1, new_pnum, 0, data_size);
+ if (err)
goto write_error;
- }
- vfree(new_buf);
+ mutex_unlock(&ubi->buf_mutex);
ubi_free_vid_hdr(ubi, vid_hdr);
vol->eba_tbl[lnum] = new_pnum;
@@ -558,6 +551,7 @@
return 0;
out_put:
+ mutex_unlock(&ubi->buf_mutex);
ubi_wl_put_peb(ubi, new_pnum, 1);
ubi_free_vid_hdr(ubi, vid_hdr);
return err;
@@ -570,6 +564,7 @@
ubi_warn("failed to write to PEB %d", new_pnum);
ubi_wl_put_peb(ubi, new_pnum, 1);
if (++tries > UBI_IO_RETRIES) {
+ mutex_unlock(&ubi->buf_mutex);
ubi_free_vid_hdr(ubi, vid_hdr);
return err;
}
@@ -965,7 +960,6 @@
int err, vol_id, lnum, data_size, aldata_size, pnum, idx;
struct ubi_volume *vol;
uint32_t crc;
- void *buf, *buf1 = NULL;
vol_id = be32_to_cpu(vid_hdr->vol_id);
lnum = be32_to_cpu(vid_hdr->lnum);
@@ -979,19 +973,15 @@
data_size = aldata_size =
ubi->leb_size - be32_to_cpu(vid_hdr->data_pad);
- buf = vmalloc(aldata_size);
- if (!buf)
- return -ENOMEM;
-
/*
* We do not want anybody to write to this logical eraseblock while we
* are moving it, so we lock it.
*/
err = leb_write_lock(ubi, vol_id, lnum);
- if (err) {
- vfree(buf);
+ if (err)
return err;
- }
+
+ mutex_lock(&ubi->buf_mutex);
/*
* But the logical eraseblock might have been put by this time.
@@ -1023,7 +1013,7 @@
/* OK, now the LEB is locked and we can safely start moving it */
dbg_eba("read %d bytes of data", aldata_size);
- err = ubi_io_read_data(ubi, buf, from, 0, aldata_size);
+ err = ubi_io_read_data(ubi, ubi->peb_buf1, from, 0, aldata_size);
if (err && err != UBI_IO_BITFLIPS) {
ubi_warn("error %d while reading data from PEB %d",
err, from);
@@ -1042,10 +1032,10 @@
*/
if (vid_hdr->vol_type == UBI_VID_DYNAMIC)
aldata_size = data_size =
- ubi_calc_data_len(ubi, buf, data_size);
+ ubi_calc_data_len(ubi, ubi->peb_buf1, data_size);
cond_resched();
- crc = crc32(UBI_CRC32_INIT, buf, data_size);
+ crc = crc32(UBI_CRC32_INIT, ubi->peb_buf1, data_size);
cond_resched();
/*
@@ -1076,23 +1066,18 @@
}
if (data_size > 0) {
- err = ubi_io_write_data(ubi, buf, to, 0, aldata_size);
+ err = ubi_io_write_data(ubi, ubi->peb_buf1, to, 0, aldata_size);
if (err)
goto out_unlock;
+ cond_resched();
+
/*
* We've written the data and are going to read it back to make
* sure it was written correctly.
*/
- buf1 = vmalloc(aldata_size);
- if (!buf1) {
- err = -ENOMEM;
- goto out_unlock;
- }
- cond_resched();
-
- err = ubi_io_read_data(ubi, buf1, to, 0, aldata_size);
+ err = ubi_io_read_data(ubi, ubi->peb_buf2, to, 0, aldata_size);
if (err) {
if (err != UBI_IO_BITFLIPS)
ubi_warn("cannot read data back from PEB %d",
@@ -1102,7 +1087,7 @@
cond_resched();
- if (memcmp(buf, buf1, aldata_size)) {
+ if (memcmp(ubi->peb_buf1, ubi->peb_buf2, aldata_size)) {
ubi_warn("read data back from PEB %d - it is different",
to);
goto out_unlock;
@@ -1112,16 +1097,9 @@
ubi_assert(vol->eba_tbl[lnum] == from);
vol->eba_tbl[lnum] = to;
- leb_write_unlock(ubi, vol_id, lnum);
- vfree(buf);
- vfree(buf1);
-
- return 0;
-
out_unlock:
+ mutex_unlock(&ubi->buf_mutex);
leb_write_unlock(ubi, vol_id, lnum);
- vfree(buf);
- vfree(buf1);
return err;
}