UBI: introduce the VID buffer concept

Currently, all VID headers are allocated and freed using the
ubi_zalloc_vid_hdr() and ubi_free_vid_hdr() function. These functions
make sure to align allocation on ubi->vid_hdr_alsize and adjust the
vid_hdr pointer to match the ubi->vid_hdr_shift requirements.
This works fine, but is a bit convoluted.
Moreover, the future introduction of LEB consolidation (needed to support
MLC/TLC NANDs) will allows a VID buffer to contain more than one VID
header.

Hence the creation of a ubi_vid_io_buf struct to attach extra information
to the VID header.

We currently only store the actual pointer of the underlying buffer, but
will soon add the number of VID headers contained in the buffer.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

1 files changed, 43 insertions, 28 deletions

diff --git a/drivers/mtd/ubi/fastmap.c b/drivers/mtd/ubi/fastmap.c
index 27a94f28819b..4adffb893376 100644
--- a/drivers/mtd/ubi/fastmap.c
+++ b/drivers/mtd/ubi/fastmap.c
@@ -110,21 +110,23 @@ size_t ubi_calc_fm_size(struct ubi_device *ubi)
  * Returns a new struct ubi_vid_hdr on success.
  * NULL indicates out of memory.
  */
-static struct ubi_vid_hdr *new_fm_vhdr(struct ubi_device *ubi, int vol_id)
+static struct ubi_vid_io_buf *new_fm_vbuf(struct ubi_device *ubi, int vol_id)
 {
-	struct ubi_vid_hdr *new;
+	struct ubi_vid_io_buf *new;
+	struct ubi_vid_hdr *vh;
 
-	new = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
+	new = ubi_alloc_vid_buf(ubi, GFP_KERNEL);
 	if (!new)
 		goto out;
 
-	new->vol_type = UBI_VID_DYNAMIC;
-	new->vol_id = cpu_to_be32(vol_id);
+	vh = ubi_get_vid_hdr(new);
+	vh->vol_type = UBI_VID_DYNAMIC;
+	vh->vol_id = cpu_to_be32(vol_id);
 
 	/* UBI implementations without fastmap support have to delete the
 	 * fastmap.
 	 */
-	new->compat = UBI_COMPAT_DELETE;
+	vh->compat = UBI_COMPAT_DELETE;
 
 out:
 	return new;
@@ -408,6 +410,7 @@ static int scan_pool(struct ubi_device *ubi, struct ubi_attach_info *ai,
 		     __be32 *pebs, int pool_size, unsigned long long *max_sqnum,
 		     struct list_head *free)
 {
+	struct ubi_vid_io_buf *vb;
 	struct ubi_vid_hdr *vh;
 	struct ubi_ec_hdr *ech;
 	struct ubi_ainf_peb *new_aeb;
@@ -417,12 +420,14 @@ static int scan_pool(struct ubi_device *ubi, struct ubi_attach_info *ai,
 	if (!ech)
 		return -ENOMEM;
 
-	vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
-	if (!vh) {
+	vb = ubi_alloc_vid_buf(ubi, GFP_KERNEL);
+	if (!vb) {
 		kfree(ech);
 		return -ENOMEM;
 	}
 
+	vh = ubi_get_vid_hdr(vb);
+
 	dbg_bld("scanning fastmap pool: size = %i", pool_size);
 
 	/*
@@ -463,7 +468,7 @@ static int scan_pool(struct ubi_device *ubi, struct ubi_attach_info *ai,
 			goto out;
 		}
 
-		err = ubi_io_read_vid_hdr(ubi, pnum, vh, 0);
+		err = ubi_io_read_vid_hdr(ubi, pnum, vb, 0);
 		if (err == UBI_IO_FF || err == UBI_IO_FF_BITFLIPS) {
 			unsigned long long ec = be64_to_cpu(ech->ec);
 			unmap_peb(ai, pnum);
@@ -509,7 +514,7 @@ static int scan_pool(struct ubi_device *ubi, struct ubi_attach_info *ai,
 	}
 
 out:
-	ubi_free_vid_hdr(ubi, vh);
+	ubi_free_vid_buf(vb);
 	kfree(ech);
 	return ret;
 }
@@ -837,6 +842,7 @@ int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
 		     struct ubi_attach_info *scan_ai)
 {
 	struct ubi_fm_sb *fmsb, *fmsb2;
+	struct ubi_vid_io_buf *vb;
 	struct ubi_vid_hdr *vh;
 	struct ubi_ec_hdr *ech;
 	struct ubi_fastmap_layout *fm;
@@ -912,12 +918,14 @@ int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
 		goto free_fm_sb;
 	}
 
-	vh = ubi_zalloc_vid_hdr(ubi, GFP_KERNEL);
-	if (!vh) {
+	vb = ubi_alloc_vid_buf(ubi, GFP_KERNEL);
+	if (!vb) {
 		ret = -ENOMEM;
 		goto free_hdr;
 	}
 
+	vh = ubi_get_vid_hdr(vb);
+
 	for (i = 0; i < used_blocks; i++) {
 		int image_seq;
 
@@ -960,7 +968,7 @@ int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
 			goto free_hdr;
 		}
 
-		ret = ubi_io_read_vid_hdr(ubi, pnum, vh, 0);
+		ret = ubi_io_read_vid_hdr(ubi, pnum, vb, 0);
 		if (ret && ret != UBI_IO_BITFLIPS) {
 			ubi_err(ubi, "unable to read fastmap block# %i (PEB: %i)",
 				i, pnum);
@@ -1050,7 +1058,7 @@ int ubi_scan_fastmap(struct ubi_device *ubi, struct ubi_attach_info *ai,
 	ubi->fm_disabled = 0;
 	ubi->fast_attach = 1;
 
-	ubi_free_vid_hdr(ubi, vh);
+	ubi_free_vid_buf(vb);
 	kfree(ech);
 out:
 	up_write(&ubi->fm_protect);
@@ -1059,7 +1067,7 @@ out:
 	return ret;
 
 free_hdr:
-	ubi_free_vid_hdr(ubi, vh);
+	ubi_free_vid_buf(vb);
 	kfree(ech);
 free_fm_sb:
 	kfree(fmsb);
@@ -1087,6 +1095,7 @@ static int ubi_write_fastmap(struct ubi_device *ubi,
 	struct ubi_fm_eba *feba;
 	struct ubi_wl_entry *wl_e;
 	struct ubi_volume *vol;
+	struct ubi_vid_io_buf *avbuf, *dvbuf;
 	struct ubi_vid_hdr *avhdr, *dvhdr;
 	struct ubi_work *ubi_wrk;
 	struct rb_node *tmp_rb;
@@ -1097,18 +1106,21 @@ static int ubi_write_fastmap(struct ubi_device *ubi,
 	fm_raw = ubi->fm_buf;
 	memset(ubi->fm_buf, 0, ubi->fm_size);
 
-	avhdr = new_fm_vhdr(ubi, UBI_FM_SB_VOLUME_ID);
-	if (!avhdr) {
+	avbuf = new_fm_vbuf(ubi, UBI_FM_SB_VOLUME_ID);
+	if (!avbuf) {
 		ret = -ENOMEM;
 		goto out;
 	}
 
-	dvhdr = new_fm_vhdr(ubi, UBI_FM_DATA_VOLUME_ID);
-	if (!dvhdr) {
+	dvbuf = new_fm_vbuf(ubi, UBI_FM_DATA_VOLUME_ID);
+	if (!dvbuf) {
 		ret = -ENOMEM;
 		goto out_kfree;
 	}
 
+	avhdr = ubi_get_vid_hdr(avbuf);
+	dvhdr = ubi_get_vid_hdr(dvbuf);
+
 	seen_pebs = init_seen(ubi);
 	if (IS_ERR(seen_pebs)) {
 		ret = PTR_ERR(seen_pebs);
@@ -1277,7 +1289,7 @@ static int ubi_write_fastmap(struct ubi_device *ubi,
 	spin_unlock(&ubi->volumes_lock);
 
 	dbg_bld("writing fastmap SB to PEB %i", new_fm->e[0]->pnum);
-	ret = ubi_io_write_vid_hdr(ubi, new_fm->e[0]->pnum, avhdr);
+	ret = ubi_io_write_vid_hdr(ubi, new_fm->e[0]->pnum, avbuf);
 	if (ret) {
 		ubi_err(ubi, "unable to write vid_hdr to fastmap SB!");
 		goto out_kfree;
@@ -1298,7 +1310,7 @@ static int ubi_write_fastmap(struct ubi_device *ubi,
 		dvhdr->lnum = cpu_to_be32(i);
 		dbg_bld("writing fastmap data to PEB %i sqnum %llu",
 			new_fm->e[i]->pnum, be64_to_cpu(dvhdr->sqnum));
-		ret = ubi_io_write_vid_hdr(ubi, new_fm->e[i]->pnum, dvhdr);
+		ret = ubi_io_write_vid_hdr(ubi, new_fm->e[i]->pnum, dvbuf);
 		if (ret) {
 			ubi_err(ubi, "unable to write vid_hdr to PEB %i!",
 				new_fm->e[i]->pnum);
@@ -1323,8 +1335,8 @@ static int ubi_write_fastmap(struct ubi_device *ubi,
 	dbg_bld("fastmap written!");
 
 out_kfree:
-	ubi_free_vid_hdr(ubi, avhdr);
-	ubi_free_vid_hdr(ubi, dvhdr);
+	ubi_free_vid_buf(avbuf);
+	ubi_free_vid_buf(dvbuf);
 	free_seen(seen_pebs);
 out:
 	return ret;
@@ -1394,7 +1406,8 @@ static int invalidate_fastmap(struct ubi_device *ubi)
 	int ret;
 	struct ubi_fastmap_layout *fm;
 	struct ubi_wl_entry *e;
-	struct ubi_vid_hdr *vh = NULL;
+	struct ubi_vid_io_buf *vb = NULL;
+	struct ubi_vid_hdr *vh;
 
 	if (!ubi->fm)
 		return 0;
@@ -1406,10 +1419,12 @@ static int invalidate_fastmap(struct ubi_device *ubi)
 	if (!fm)
 		goto out;
 
-	vh = new_fm_vhdr(ubi, UBI_FM_SB_VOLUME_ID);
-	if (!vh)
+	vb = new_fm_vbuf(ubi, UBI_FM_SB_VOLUME_ID);
+	if (!vb)
 		goto out_free_fm;
 
+	vh = ubi_get_vid_hdr(vb);
+
 	ret = -ENOSPC;
 	e = ubi_wl_get_fm_peb(ubi, 1);
 	if (!e)
@@ -1420,7 +1435,7 @@ static int invalidate_fastmap(struct ubi_device *ubi)
 	 * to scanning mode.
 	 */
 	vh->sqnum = cpu_to_be64(ubi_next_sqnum(ubi));
-	ret = ubi_io_write_vid_hdr(ubi, e->pnum, vh);
+	ret = ubi_io_write_vid_hdr(ubi, e->pnum, vb);
 	if (ret < 0) {
 		ubi_wl_put_fm_peb(ubi, e, 0, 0);
 		goto out_free_fm;
@@ -1432,7 +1447,7 @@ static int invalidate_fastmap(struct ubi_device *ubi)
 	ubi->fm = fm;
 
 out:
-	ubi_free_vid_hdr(ubi, vh);
+	ubi_free_vid_buf(vb);
 	return ret;
 
 out_free_fm: