[PATCH 7/7] [RFC] UBI: wire up checkpointing
From: Richard Weinberger
Date: Wed May 09 2012 - 13:41:06 EST
Signed-off-by: Richard Weinberger <richard@xxxxxx>
---
drivers/mtd/ubi/Kconfig | 29 ++++++++++++++-
drivers/mtd/ubi/build.c | 86 ++++++++++++++++++++++++++++++++++++++++++
drivers/mtd/ubi/checkpoint.c | 4 ++
drivers/mtd/ubi/ubi-media.h | 6 +-
4 files changed, 121 insertions(+), 4 deletions(-)
diff --git a/drivers/mtd/ubi/Kconfig b/drivers/mtd/ubi/Kconfig
index 3ba9978..12888a4 100644
--- a/drivers/mtd/ubi/Kconfig
+++ b/drivers/mtd/ubi/Kconfig
@@ -56,10 +56,37 @@ config MTD_UBI_CHECKPOINT
depends on EXPERIMENTAL
default n
help
- This option enables UBIVIS (AKA checkpointing).
+ This option enables UBIVIS (aka checkpointing).
It allows attaching UBI devices without scanning the whole MTD
device. Instead it extracts all needed information from a checkpoint.
+config MTD_UBI_CHECKPOINT_POOL_SIZE
+ int "Max number of PEBs in a UBIVIS pool"
+ range 10 1024
+ default 128
+ help
+ This is the number PEBs which have to be scanned while attaching.
+ A low value means that attaching will be faster but if the value
+ is too small the checkpoint has to be written too often.
+ Every time the pool is full a new checkpoint is written to the MTD.
+ Note that we have currently three pools.
+ Choose wisely!
+
+config MTD_UBI_CHECKPOINT_MAX_SIZE
+ int "Maximal size of a checkpoint in PEBs"
+ range 10 128
+ default 32
+ help
+ Maximale size of a checkpoint in PEBs.
+
+config MTD_UBI_CHECKPOINT_SB_POS
+ int "Checkpoint super block position"
+ range 4 128
+ default 64
+ help
+ The checkpoint super block will be placed within the first N PEBs.
+ Is this value too large it takes longer to find the checkpoint.
+
config MTD_UBI_DEBUG
bool "UBI debugging"
depends on SYSFS
diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index 0fde9fc..316f27a 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -148,6 +148,17 @@ int ubi_volume_notify(struct ubi_device *ubi, struct ubi_volume *vol, int ntype)
ubi_do_get_device_info(ubi, &nt.di);
ubi_do_get_volume_info(ubi, vol, &nt.vi);
+
+#ifdef CONFIG_MTD_UBI_CHECKPOINT
+ switch (ntype) {
+ case UBI_VOLUME_ADDED:
+ case UBI_VOLUME_REMOVED:
+ case UBI_VOLUME_RESIZED:
+ case UBI_VOLUME_RENAMED:
+ if (ubi_update_checkpoint(ubi))
+ ubi_err("Unable to update checkpoint!");
+ }
+#endif
return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt);
}
@@ -852,6 +863,61 @@ static int autoresize(struct ubi_device *ubi, int vol_id)
return 0;
}
+#ifdef CONFIG_MTD_UBI_CHECKPOINT
+static int attach_by_checkpointing(struct ubi_device *ubi)
+{
+ int cp_start, err;
+ struct ubi_scan_info *si;
+
+ cp_start = ubi_find_checkpoint(ubi);
+ if (cp_start < 0)
+ return -ENOENT;
+
+ si = ubi_read_checkpoint(ubi, cp_start);
+ if (IS_ERR(si))
+ return PTR_ERR(si);
+
+ ubi->bad_peb_count = 0;
+ ubi->good_peb_count = ubi->peb_count;
+ ubi->corr_peb_count = 0;
+ ubi->max_ec = si->max_ec;
+ ubi->mean_ec = si->mean_ec;
+ ubi_msg("max. sequence number: %llu", si->max_sqnum);
+
+ err = ubi_read_volume_table(ubi, si);
+ if (err) {
+ ubi_err("ubi_read_volume_table failed");
+ goto out_si;
+ }
+
+ err = ubi_wl_init_scan(ubi, si);
+ if (err) {
+ ubi_err("ubi_wl_init_scan failed!");
+ goto out_vtbl;
+ }
+
+ err = ubi_eba_init_scan(ubi, si);
+ if (err) {
+ ubi_err("ubi_eba_init_scan failed!");
+ goto out_wl;
+ }
+
+ ubi_msg("successfully recovered from checkpoint!");
+ ubi_scan_destroy_si(si);
+ return 0;
+
+out_wl:
+ ubi_wl_close(ubi);
+out_vtbl:
+ free_internal_volumes(ubi);
+ vfree(ubi->vtbl);
+out_si:
+ ubi_scan_destroy_si(si);
+
+ return err;
+}
+#endif
+
/**
* ubi_attach_mtd_dev - attach an MTD device.
* @mtd: MTD device description object
@@ -931,6 +997,15 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset)
ubi->vid_hdr_offset = vid_hdr_offset;
ubi->autoresize_vol_id = -1;
+#ifdef CONFIG_MTD_UBI_CHECKPOINT
+ ubi->long_pool.used = ubi->long_pool.size = \
+ ubi->long_pool.max_size = ARRAY_SIZE(ubi->long_pool.pebs);
+ ubi->short_pool.used = ubi->short_pool.size = \
+ ubi->short_pool.max_size = ARRAY_SIZE(ubi->short_pool.pebs);
+ ubi->unk_pool.used = ubi->unk_pool.size = \
+ ubi->unk_pool.max_size = ARRAY_SIZE(ubi->unk_pool.pebs);
+#endif
+
mutex_init(&ubi->buf_mutex);
mutex_init(&ubi->ckvol_mutex);
mutex_init(&ubi->device_mutex);
@@ -953,7 +1028,18 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num, int vid_hdr_offset)
if (err)
goto out_free;
+#ifdef CONFIG_MTD_UBI_CHECKPOINT
+ err = attach_by_checkpointing(ubi);
+
+ if (err) {
+ if (err != -ENOENT)
+ ubi_msg("falling back to attach by scanning mode!\n");
+
+ err = attach_by_scanning(ubi);
+ }
+#else
err = attach_by_scanning(ubi);
+#endif
if (err) {
dbg_err("failed to attach by scanning, error %d", err);
goto out_debugging;
diff --git a/drivers/mtd/ubi/checkpoint.c b/drivers/mtd/ubi/checkpoint.c
index f43441c..867f32d 100644
--- a/drivers/mtd/ubi/checkpoint.c
+++ b/drivers/mtd/ubi/checkpoint.c
@@ -993,6 +993,10 @@ int ubi_update_checkpoint(struct ubi_device *ubi)
int ret, i;
struct ubi_checkpoint *new_cp;
+ BUILD_BUG_ON(UBI_CP_MAX_START < 3);
+ BUILD_BUG_ON(UBI_CP_MAX_BLOCKS < 10);
+ BUILD_BUG_ON(UBI_CP_MAX_POOL_SIZE < 10);
+
if (ubi->ro_mode)
return 0;
diff --git a/drivers/mtd/ubi/ubi-media.h b/drivers/mtd/ubi/ubi-media.h
index 7223b02..4d14b9e 100644
--- a/drivers/mtd/ubi/ubi-media.h
+++ b/drivers/mtd/ubi/ubi-media.h
@@ -382,9 +382,9 @@ struct ubi_vtbl_record {
/* Checkoint format version */
#define UBI_CP_FMT_VERSION 1
-#define UBI_CP_MAX_START 64
-#define UBI_CP_MAX_BLOCKS 32
-#define UBI_CP_MAX_POOL_SIZE 128
+#define UBI_CP_MAX_START CONFIG_MTD_UBI_CHECKPOINT_SB_POS
+#define UBI_CP_MAX_BLOCKS CONFIG_MTD_UBI_CHECKPOINT_MAX_SIZE
+#define UBI_CP_MAX_POOL_SIZE CONFIG_MTD_UBI_CHECKPOINT_POOL_SIZE
#define UBI_CP_SB_MAGIC 0x7B11D69F
#define UBI_CP_HDR_MAGIC 0xD4B82EF7
#define UBI_CP_VHDR_MAGIC 0xFA370ED1
--
1.7.6.5
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