summaryrefslogtreecommitdiffstats
path: root/drivers/mtd
diff options
context:
space:
mode:
authorArtem Bityutskiy <Artem.Bityutskiy@nokia.com>2009-05-23 15:04:17 +0200
committerArtem Bityutskiy <Artem.Bityutskiy@nokia.com>2009-06-02 12:53:35 +0200
commit90bf0265e5b0d561f215a69bb7a46c4071b2c93b (patch)
tree7b3b1cb2f394687b5e0f841031200e9c37faef92 /drivers/mtd
parentUBI: fix race condition (diff)
downloadlinux-90bf0265e5b0d561f215a69bb7a46c4071b2c93b.tar.xz
linux-90bf0265e5b0d561f215a69bb7a46c4071b2c93b.zip
UBI: introduce new constants
This patch is a clean-up and a preparation for the following patches. It introduece constants for the return values of the 'ubi_eba_copy_leb()' function. Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Diffstat (limited to 'drivers/mtd')
-rw-r--r--drivers/mtd/ubi/eba.c33
-rw-r--r--drivers/mtd/ubi/ubi.h16
-rw-r--r--drivers/mtd/ubi/wl.c13
3 files changed, 36 insertions, 26 deletions
diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c
index 25def348e5ba..7ab79e247245 100644
--- a/drivers/mtd/ubi/eba.c
+++ b/drivers/mtd/ubi/eba.c
@@ -950,12 +950,7 @@ write_error:
* physical eraseblock @to. The @vid_hdr buffer may be changed by this
* function. Returns:
* o %0 in case of success;
- * o %1 if the operation was canceled because the volume is being deleted
- * or because the PEB was put meanwhile;
- * o %2 if the operation was canceled because there was a write error to the
- * target PEB;
- * o %-EAGAIN if the operation was canceled because a bit-flip was detected
- * in the target PEB;
+ * o %MOVE_CANCEL_RACE, %MOVE_TARGET_WR_ERR, or %MOVE_CANCEL_BITFLIPS;
* o a negative error code in case of failure.
*/
int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
@@ -986,13 +981,12 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
* be locked in 'ubi_wl_put_peb()' and wait for the WL worker to finish.
*/
vol = ubi->volumes[idx];
+ spin_unlock(&ubi->volumes_lock);
if (!vol) {
/* No need to do further work, cancel */
dbg_eba("volume %d is being removed, cancel", vol_id);
- spin_unlock(&ubi->volumes_lock);
- return 1;
+ return MOVE_CANCEL_RACE;
}
- spin_unlock(&ubi->volumes_lock);
/*
* We do not want anybody to write to this logical eraseblock while we
@@ -1004,12 +998,13 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
* (@from). This task locks the LEB and goes sleep in the
* 'ubi_wl_put_peb()' function on the @ubi->move_mutex. In turn, we are
* holding @ubi->move_mutex and go sleep on the LEB lock. So, if the
- * LEB is already locked, we just do not move it and return %1.
+ * LEB is already locked, we just do not move it and return
+ * %MOVE_CANCEL_RACE, which means that UBI will re-try, but later.
*/
err = leb_write_trylock(ubi, vol_id, lnum);
if (err) {
dbg_eba("contention on LEB %d:%d, cancel", vol_id, lnum);
- return err;
+ return MOVE_CANCEL_RACE;
}
/*
@@ -1021,14 +1016,14 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
dbg_eba("LEB %d:%d is no longer mapped to PEB %d, mapped to "
"PEB %d, cancel", vol_id, lnum, from,
vol->eba_tbl[lnum]);
- err = 1;
+ err = MOVE_CANCEL_RACE;
goto out_unlock_leb;
}
/*
* OK, now the LEB is locked and we can safely start moving it. Since
- * this function utilizes the @ubi->peb1_buf buffer which is shared
- * with some other functions, so lock the buffer by taking the
+ * this function utilizes the @ubi->peb_buf1 buffer which is shared
+ * with some other functions - we lock the buffer by taking the
* @ubi->buf_mutex.
*/
mutex_lock(&ubi->buf_mutex);
@@ -1059,7 +1054,7 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
cond_resched();
/*
- * It may turn out to me that the whole @from physical eraseblock
+ * It may turn out to be that the whole @from physical eraseblock
* contains only 0xFF bytes. Then we have to only write the VID header
* and do not write any data. This also means we should not set
* @vid_hdr->copy_flag, @vid_hdr->data_size, and @vid_hdr->data_crc.
@@ -1074,7 +1069,7 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
err = ubi_io_write_vid_hdr(ubi, to, vid_hdr);
if (err) {
if (err == -EIO)
- err = 2;
+ err = MOVE_TARGET_WR_ERR;
goto out_unlock_buf;
}
@@ -1086,7 +1081,7 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
if (err != UBI_IO_BITFLIPS)
ubi_warn("cannot read VID header back from PEB %d", to);
else
- err = -EAGAIN;
+ err = MOVE_CANCEL_BITFLIPS;
goto out_unlock_buf;
}
@@ -1094,7 +1089,7 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
err = ubi_io_write_data(ubi, ubi->peb_buf1, to, 0, aldata_size);
if (err) {
if (err == -EIO)
- err = 2;
+ err = MOVE_TARGET_WR_ERR;
goto out_unlock_buf;
}
@@ -1111,7 +1106,7 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
ubi_warn("cannot read data back from PEB %d",
to);
else
- err = -EAGAIN;
+ err = MOVE_CANCEL_BITFLIPS;
goto out_unlock_buf;
}
diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h
index 749007e9f1aa..fd9b20da5b6b 100644
--- a/drivers/mtd/ubi/ubi.h
+++ b/drivers/mtd/ubi/ubi.h
@@ -100,6 +100,22 @@ enum {
UBI_IO_BITFLIPS
};
+/*
+ * Return codes of the 'ubi_eba_copy_leb()' function.
+ *
+ * MOVE_CANCEL_RACE: canceled because the volume is being deleted, the source
+ * PEB was put meanwhile, or there is I/O on the source PEB
+ * MOVE_TARGET_WR_ERR: canceled because there was a write error to the target
+ * PEB
+ * MOVE_CANCEL_BITFLIPS: canceled because a bit-flip was detected in the
+ * target PEB
+ */
+enum {
+ MOVE_CANCEL_RACE = 1,
+ MOVE_TARGET_WR_ERR,
+ MOVE_CANCEL_BITFLIPS,
+};
+
/**
* struct ubi_wl_entry - wear-leveling entry.
* @u.rb: link in the corresponding (free/used) RB-tree
diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
index 891534f8210d..ec915c02301c 100644
--- a/drivers/mtd/ubi/wl.c
+++ b/drivers/mtd/ubi/wl.c
@@ -756,15 +756,14 @@ static int wear_leveling_worker(struct ubi_device *ubi, struct ubi_work *wrk,
err = ubi_eba_copy_leb(ubi, e1->pnum, e2->pnum, vid_hdr);
if (err) {
- if (err == -EAGAIN)
- goto out_not_moved;
- if (err < 0)
- goto out_error;
- if (err == 2) {
- /* Target PEB write error, torture it */
+ if (err == MOVE_CANCEL_BITFLIPS ||
+ err == MOVE_TARGET_WR_ERR) {
+ /* Target PEB bit-flips or write error, torture it */
torture = 1;
goto out_not_moved;
}
+ if (err < 0)
+ goto out_error;
/*
* The LEB has not been moved because the volume is being
@@ -774,7 +773,7 @@ static int wear_leveling_worker(struct ubi_device *ubi, struct ubi_work *wrk,
*/
dbg_wl("canceled moving PEB %d", e1->pnum);
- ubi_assert(err == 1);
+ ubi_assert(err == MOVE_CANCEL_RACE);
ubi_free_vid_hdr(ubi, vid_hdr);
vid_hdr = NULL;