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path: root/drivers/mtd/ubi/eba.c
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Diffstat (limited to 'drivers/mtd/ubi/eba.c')
-rw-r--r--drivers/mtd/ubi/eba.c99
1 files changed, 64 insertions, 35 deletions
diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c
index 25def348e5b..0f2034c3ed2 100644
--- a/drivers/mtd/ubi/eba.c
+++ b/drivers/mtd/ubi/eba.c
@@ -419,8 +419,9 @@ retry:
* not implemented.
*/
if (err == UBI_IO_BAD_VID_HDR) {
- ubi_warn("bad VID header at PEB %d, LEB"
- "%d:%d", pnum, vol_id, lnum);
+ ubi_warn("corrupted VID header at PEB "
+ "%d, LEB %d:%d", pnum, vol_id,
+ lnum);
err = -EBADMSG;
} else
ubi_ro_mode(ubi);
@@ -940,6 +941,33 @@ write_error:
}
/**
+ * is_error_sane - check whether a read error is sane.
+ * @err: code of the error happened during reading
+ *
+ * This is a helper function for 'ubi_eba_copy_leb()' which is called when we
+ * cannot read data from the target PEB (an error @err happened). If the error
+ * code is sane, then we treat this error as non-fatal. Otherwise the error is
+ * fatal and UBI will be switched to R/O mode later.
+ *
+ * The idea is that we try not to switch to R/O mode if the read error is
+ * something which suggests there was a real read problem. E.g., %-EIO. Or a
+ * memory allocation failed (-%ENOMEM). Otherwise, it is safer to switch to R/O
+ * mode, simply because we do not know what happened at the MTD level, and we
+ * cannot handle this. E.g., the underlying driver may have become crazy, and
+ * it is safer to switch to R/O mode to preserve the data.
+ *
+ * And bear in mind, this is about reading from the target PEB, i.e. the PEB
+ * which we have just written.
+ */
+static int is_error_sane(int err)
+{
+ if (err == -EIO || err == -ENOMEM || err == UBI_IO_BAD_VID_HDR ||
+ err == -ETIMEDOUT)
+ return 0;
+ return 1;
+}
+
+/**
* ubi_eba_copy_leb - copy logical eraseblock.
* @ubi: UBI device description object
* @from: physical eraseblock number from where to copy
@@ -950,12 +978,7 @@ 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, %MOVE_CANCEL_BITFLIPS, etc;
* o a negative error code in case of failure.
*/
int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
@@ -968,7 +991,7 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
vol_id = be32_to_cpu(vid_hdr->vol_id);
lnum = be32_to_cpu(vid_hdr->lnum);
- dbg_eba("copy LEB %d:%d, PEB %d to PEB %d", vol_id, lnum, from, to);
+ dbg_wl("copy LEB %d:%d, PEB %d to PEB %d", vol_id, lnum, from, to);
if (vid_hdr->vol_type == UBI_VID_STATIC) {
data_size = be32_to_cpu(vid_hdr->data_size);
@@ -986,13 +1009,12 @@ 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;
+ dbg_wl("volume %d is being removed, cancel", vol_id);
+ return MOVE_CANCEL_RACE;
}
- spin_unlock(&ubi->volumes_lock);
/*
* We do not want anybody to write to this logical eraseblock while we
@@ -1004,12 +1026,13 @@ 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;
+ dbg_wl("contention on LEB %d:%d, cancel", vol_id, lnum);
+ return MOVE_CANCEL_RACE;
}
/*
@@ -1018,25 +1041,26 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
* cancel it.
*/
if (vol->eba_tbl[lnum] != from) {
- 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;
+ dbg_wl("LEB %d:%d is no longer mapped to PEB %d, mapped to "
+ "PEB %d, cancel", vol_id, lnum, from,
+ vol->eba_tbl[lnum]);
+ 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);
- dbg_eba("read %d bytes of data", aldata_size);
+ dbg_wl("read %d bytes of data", 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);
+ err = MOVE_SOURCE_RD_ERR;
goto out_unlock_buf;
}
@@ -1059,7 +1083,7 @@ 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 +1098,7 @@ 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;
}
@@ -1083,10 +1107,13 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
/* Read the VID header back and check if it was written correctly */
err = ubi_io_read_vid_hdr(ubi, to, vid_hdr, 1);
if (err) {
- if (err != UBI_IO_BITFLIPS)
- ubi_warn("cannot read VID header back from PEB %d", to);
- else
- err = -EAGAIN;
+ if (err != UBI_IO_BITFLIPS) {
+ ubi_warn("error %d while reading VID header back from "
+ "PEB %d", err, to);
+ if (is_error_sane(err))
+ err = MOVE_TARGET_RD_ERR;
+ } else
+ err = MOVE_CANCEL_BITFLIPS;
goto out_unlock_buf;
}
@@ -1094,7 +1121,7 @@ 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;
}
@@ -1107,11 +1134,13 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
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",
- to);
- else
- err = -EAGAIN;
+ if (err != UBI_IO_BITFLIPS) {
+ ubi_warn("error %d while reading data back "
+ "from PEB %d", err, to);
+ if (is_error_sane(err))
+ err = MOVE_TARGET_RD_ERR;
+ } else
+ err = MOVE_CANCEL_BITFLIPS;
goto out_unlock_buf;
}