UBI: hide EBA internals
Create a private ubi_eba_table struct to hide EBA internals and provide
helpers to allocate, destroy, copy and assing an EBA table to a volume.
Now that external EBA users are using helpers to query/modify the EBA
state we can safely change the internal representation, which will be
needed to support the LEB consolidation concept.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c
index f3ff860..884c91f 100644
--- a/drivers/mtd/ubi/eba.c
+++ b/drivers/mtd/ubi/eba.c
@@ -50,6 +50,30 @@
#define EBA_RESERVED_PEBS 1
/**
+ * struct ubi_eba_entry - structure encoding a single LEB -> PEB association
+ * @pnum: the physical eraseblock number attached to the LEB
+ *
+ * This structure is encoding a LEB -> PEB association. Note that the LEB
+ * number is not stored here, because it is the index used to access the
+ * entries table.
+ */
+struct ubi_eba_entry {
+ int pnum;
+};
+
+/**
+ * struct ubi_eba_table - LEB -> PEB association information
+ * @entries: the LEB to PEB mapping (one entry per LEB).
+ *
+ * This structure is private to the EBA logic and should be kept here.
+ * It is encoding the LEB to PEB association table, and is subject to
+ * changes.
+ */
+struct ubi_eba_table {
+ struct ubi_eba_entry *entries;
+};
+
+/**
* next_sqnum - get next sequence number.
* @ubi: UBI device description object
*
@@ -97,7 +121,94 @@
struct ubi_eba_leb_desc *ldesc)
{
ldesc->lnum = lnum;
- ldesc->pnum = vol->eba_tbl[lnum];
+ ldesc->pnum = vol->eba_tbl->entries[lnum].pnum;
+}
+
+/**
+ * ubi_eba_create_table - allocate a new EBA table and initialize it with all
+ * LEBs unmapped
+ * @vol: volume containing the EBA table to copy
+ * @nentries: number of entries in the table
+ *
+ * Allocate a new EBA table and initialize it with all LEBs unmapped.
+ * Returns a valid pointer if it succeed, an ERR_PTR() otherwise.
+ */
+struct ubi_eba_table *ubi_eba_create_table(struct ubi_volume *vol,
+ int nentries)
+{
+ struct ubi_eba_table *tbl;
+ int err = -ENOMEM;
+ int i;
+
+ tbl = kzalloc(sizeof(*tbl), GFP_KERNEL);
+ if (!tbl)
+ return ERR_PTR(-ENOMEM);
+
+ tbl->entries = kmalloc_array(nentries, sizeof(*tbl->entries),
+ GFP_KERNEL);
+ if (!tbl->entries)
+ goto err;
+
+ for (i = 0; i < nentries; i++)
+ tbl->entries[i].pnum = UBI_LEB_UNMAPPED;
+
+ return tbl;
+
+err:
+ kfree(tbl->entries);
+ kfree(tbl);
+
+ return ERR_PTR(err);
+}
+
+/**
+ * ubi_eba_destroy_table - destroy an EBA table
+ * @tbl: the table to destroy
+ *
+ * Destroy an EBA table.
+ */
+void ubi_eba_destroy_table(struct ubi_eba_table *tbl)
+{
+ if (!tbl)
+ return;
+
+ kfree(tbl->entries);
+ kfree(tbl);
+}
+
+/**
+ * ubi_eba_copy_table - copy the EBA table attached to vol into another table
+ * @vol: volume containing the EBA table to copy
+ * @dst: destination
+ * @nentries: number of entries to copy
+ *
+ * Copy the EBA table stored in vol into the one pointed by dst.
+ */
+void ubi_eba_copy_table(struct ubi_volume *vol, struct ubi_eba_table *dst,
+ int nentries)
+{
+ struct ubi_eba_table *src;
+ int i;
+
+ ubi_assert(dst && vol && vol->eba_tbl);
+
+ src = vol->eba_tbl;
+
+ for (i = 0; i < nentries; i++)
+ dst->entries[i].pnum = src->entries[i].pnum;
+}
+
+/**
+ * ubi_eba_replace_table - assign a new EBA table to a volume
+ * @vol: volume containing the EBA table to copy
+ * @tbl: new EBA table
+ *
+ * Assign a new EBA table to the volume and release the old one.
+ */
+void ubi_eba_replace_table(struct ubi_volume *vol, struct ubi_eba_table *tbl)
+{
+ ubi_eba_destroy_table(vol->eba_tbl);
+ vol->eba_tbl = tbl;
}
/**
@@ -337,7 +448,7 @@
*/
bool ubi_eba_is_mapped(struct ubi_volume *vol, int lnum)
{
- return vol->eba_tbl[lnum] >= 0;
+ return vol->eba_tbl->entries[lnum].pnum >= 0;
}
/**
@@ -362,7 +473,7 @@
if (err)
return err;
- pnum = vol->eba_tbl[lnum];
+ pnum = vol->eba_tbl->entries[lnum].pnum;
if (pnum < 0)
/* This logical eraseblock is already unmapped */
goto out_unlock;
@@ -370,7 +481,7 @@
dbg_eba("erase LEB %d:%d, PEB %d", vol_id, lnum, pnum);
down_read(&ubi->fm_eba_sem);
- vol->eba_tbl[lnum] = UBI_LEB_UNMAPPED;
+ vol->eba_tbl->entries[lnum].pnum = UBI_LEB_UNMAPPED;
up_read(&ubi->fm_eba_sem);
err = ubi_wl_put_peb(ubi, vol_id, lnum, pnum, 0);
@@ -409,7 +520,7 @@
if (err)
return err;
- pnum = vol->eba_tbl[lnum];
+ pnum = vol->eba_tbl->entries[lnum].pnum;
if (pnum < 0) {
/*
* The logical eraseblock is not mapped, fill the whole buffer
@@ -658,7 +769,7 @@
mutex_unlock(&ubi->buf_mutex);
if (!err)
- vol->eba_tbl[lnum] = new_pnum;
+ vol->eba_tbl->entries[lnum].pnum = new_pnum;
out_put:
up_read(&ubi->fm_eba_sem);
@@ -749,7 +860,7 @@
goto out_put;
}
- opnum = vol->eba_tbl[lnum];
+ opnum = vol->eba_tbl->entries[lnum].pnum;
dbg_eba("write VID hdr and %d bytes at offset %d of LEB %d:%d, PEB %d",
len, offset, vol_id, lnum, pnum);
@@ -771,7 +882,7 @@
}
}
- vol->eba_tbl[lnum] = pnum;
+ vol->eba_tbl->entries[lnum].pnum = pnum;
out_put:
up_read(&ubi->fm_eba_sem);
@@ -812,7 +923,7 @@
if (err)
return err;
- pnum = vol->eba_tbl[lnum];
+ pnum = vol->eba_tbl->entries[lnum].pnum;
if (pnum >= 0) {
dbg_eba("write %d bytes at offset %d of LEB %d:%d, PEB %d",
len, offset, vol_id, lnum, pnum);
@@ -930,7 +1041,7 @@
vid_hdr->used_ebs = cpu_to_be32(used_ebs);
vid_hdr->data_crc = cpu_to_be32(crc);
- ubi_assert(vol->eba_tbl[lnum] < 0);
+ ubi_assert(vol->eba_tbl->entries[lnum].pnum < 0);
for (tries = 0; tries <= UBI_IO_RETRIES; tries++) {
err = try_write_vid_and_data(vol, lnum, vid_hdr, buf, 0, len);
@@ -1140,9 +1251,9 @@
* probably waiting on @ubi->move_mutex. No need to continue the work,
* cancel it.
*/
- if (vol->eba_tbl[lnum] != from) {
+ if (vol->eba_tbl->entries[lnum].pnum != from) {
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]);
+ vol_id, lnum, from, vol->eba_tbl->entries[lnum].pnum);
err = MOVE_CANCEL_RACE;
goto out_unlock_leb;
}
@@ -1227,9 +1338,9 @@
cond_resched();
}
- ubi_assert(vol->eba_tbl[lnum] == from);
+ ubi_assert(vol->eba_tbl->entries[lnum].pnum == from);
down_read(&ubi->fm_eba_sem);
- vol->eba_tbl[lnum] = to;
+ vol->eba_tbl->entries[lnum].pnum = to;
up_read(&ubi->fm_eba_sem);
out_unlock_buf:
@@ -1386,7 +1497,7 @@
*/
int ubi_eba_init(struct ubi_device *ubi, struct ubi_attach_info *ai)
{
- int i, j, err, num_volumes;
+ int i, err, num_volumes;
struct ubi_ainf_volume *av;
struct ubi_volume *vol;
struct ubi_ainf_peb *aeb;
@@ -1402,35 +1513,39 @@
num_volumes = ubi->vtbl_slots + UBI_INT_VOL_COUNT;
for (i = 0; i < num_volumes; i++) {
+ struct ubi_eba_table *tbl;
+
vol = ubi->volumes[i];
if (!vol)
continue;
cond_resched();
- vol->eba_tbl = kmalloc(vol->reserved_pebs * sizeof(int),
- GFP_KERNEL);
- if (!vol->eba_tbl) {
- err = -ENOMEM;
+ tbl = ubi_eba_create_table(vol, vol->reserved_pebs);
+ if (IS_ERR(tbl)) {
+ err = PTR_ERR(tbl);
goto out_free;
}
- for (j = 0; j < vol->reserved_pebs; j++)
- vol->eba_tbl[j] = UBI_LEB_UNMAPPED;
+ ubi_eba_replace_table(vol, tbl);
av = ubi_find_av(ai, idx2vol_id(ubi, i));
if (!av)
continue;
ubi_rb_for_each_entry(rb, aeb, &av->root, u.rb) {
- if (aeb->lnum >= vol->reserved_pebs)
+ if (aeb->lnum >= vol->reserved_pebs) {
/*
* This may happen in case of an unclean reboot
* during re-size.
*/
ubi_move_aeb_to_list(av, aeb, &ai->erase);
- else
- vol->eba_tbl[aeb->lnum] = aeb->pnum;
+ } else {
+ struct ubi_eba_entry *entry;
+
+ entry = &vol->eba_tbl->entries[aeb->lnum];
+ entry->pnum = aeb->pnum;
+ }
}
}
@@ -1467,8 +1582,7 @@
for (i = 0; i < num_volumes; i++) {
if (!ubi->volumes[i])
continue;
- kfree(ubi->volumes[i]->eba_tbl);
- ubi->volumes[i]->eba_tbl = NULL;
+ ubi_eba_replace_table(ubi->volumes[i], NULL);
}
return err;
}