Merge tag 'upstream-3.7-rc1-fastmap' of git://git.infradead.org/linux-ubi

Pull UBI fastmap changes from Artem Bityutskiy:
 "This pull request contains the UBI fastmap support implemented by
  Richard Weinberger from Linutronix.  Fastmap is designed to address
  UBI's slow scanning issues.  Namely, it introduces a new on-flash
  data-structure called "fastmap", which stores the information about
  logical<->physical eraseblocks mappings.  So now to get this
  information just read the fastmap, instead of doing full scan.  More
  information here can be found in Richard's announcement in LKML
  (Subject: UBI: Fastmap request for inclusion (v19)):

     http://thread.gmane.org/gmane.linux.kernel/1364922/focus=1369109

  One thing I want to explicitly say is that fastmap did not have large
  enough linux-next exposure.  It is partially my fault - I did not
  respond quickly enough.  I _really_ apologize for this.  But it had
  good testing and disabled by default, so I do not expect that we'll
  break anything.

  Fastmap is declared as experimental so far, and it is off by default.
  We did declare that the on-flash format may be changed.  The reason
  for this is that no one used it in real production so far, so there is
  a high risk that something is missing.  Besides, we do not have
  user-space tools supporting fastmap so far.

  Nevertheless, I suggest we merge this feature.  Many people want UBI's
  scanning bottleneck to be fixed and merging fastmap now should
  accelerate its production use.  The plan is to make it bullet-prove,
  somewhat clean-up, and make it the default for UBI.  I do not know how
  many kernel releases will it take.

  Basically, I what I want to do for fastmap is something like Linus did
  for btrfs few years ago."

* tag 'upstream-3.7-rc1-fastmap' of git://git.infradead.org/linux-ubi:
  UBI: Wire-up fastmap
  UBI: Add fastmap core
  UBI: Add fastmap support to the WL sub-system
  UBI: Add fastmap stuff to attach.c
  UBI: Wire-up ->fm_sem
  UBI: Add fastmap bits to build.c
  UBI: Add self_check_eba()
  UBI: Export next_sqnum()
  UBI: Add fastmap stuff to ubi.h
  UBI: Add fastmap on-flash data structures

1 files changed, 66 insertions, 4 deletions

diff --git a/drivers/mtd/ubi/build.c b/drivers/mtd/ubi/build.c
index 3497703..344b4cb 100644
--- a/drivers/mtd/ubi/build.c
+++ b/drivers/mtd/ubi/build.c
@@ -76,7 +76,10 @@ static int __initdata mtd_devs;
 
 /* MTD devices specification parameters */
 static struct mtd_dev_param __initdata mtd_dev_param[UBI_MAX_DEVICES];
-
+#ifdef CONFIG_MTD_UBI_FASTMAP
+/* UBI module parameter to enable fastmap automatically on non-fastmap images */
+static bool fm_autoconvert;
+#endif
 /* Root UBI "class" object (corresponds to '/<sysfs>/class/ubi/') */
 struct class *ubi_class;
 
@@ -153,6 +156,19 @@ 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_FASTMAP
+	switch (ntype) {
+	case UBI_VOLUME_ADDED:
+	case UBI_VOLUME_REMOVED:
+	case UBI_VOLUME_RESIZED:
+	case UBI_VOLUME_RENAMED:
+		if (ubi_update_fastmap(ubi)) {
+			ubi_err("Unable to update fastmap!");
+			ubi_ro_mode(ubi);
+		}
+	}
+#endif
 	return blocking_notifier_call_chain(&ubi_notifiers, ntype, &nt);
 }
 
@@ -918,10 +934,40 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
 	ubi->vid_hdr_offset = vid_hdr_offset;
 	ubi->autoresize_vol_id = -1;
 
+#ifdef CONFIG_MTD_UBI_FASTMAP
+	ubi->fm_pool.used = ubi->fm_pool.size = 0;
+	ubi->fm_wl_pool.used = ubi->fm_wl_pool.size = 0;
+
+	/*
+	 * fm_pool.max_size is 5% of the total number of PEBs but it's also
+	 * between UBI_FM_MAX_POOL_SIZE and UBI_FM_MIN_POOL_SIZE.
+	 */
+	ubi->fm_pool.max_size = min(((int)mtd_div_by_eb(ubi->mtd->size,
+		ubi->mtd) / 100) * 5, UBI_FM_MAX_POOL_SIZE);
+	if (ubi->fm_pool.max_size < UBI_FM_MIN_POOL_SIZE)
+		ubi->fm_pool.max_size = UBI_FM_MIN_POOL_SIZE;
+
+	ubi->fm_wl_pool.max_size = UBI_FM_WL_POOL_SIZE;
+	ubi->fm_disabled = !fm_autoconvert;
+
+	if (!ubi->fm_disabled && (int)mtd_div_by_eb(ubi->mtd->size, ubi->mtd)
+	    <= UBI_FM_MAX_START) {
+		ubi_err("More than %i PEBs are needed for fastmap, sorry.",
+			UBI_FM_MAX_START);
+		ubi->fm_disabled = 1;
+	}
+
+	ubi_msg("default fastmap pool size: %d", ubi->fm_pool.max_size);
+	ubi_msg("default fastmap WL pool size: %d", ubi->fm_wl_pool.max_size);
+#else
+	ubi->fm_disabled = 1;
+#endif
 	mutex_init(&ubi->buf_mutex);
 	mutex_init(&ubi->ckvol_mutex);
 	mutex_init(&ubi->device_mutex);
 	spin_lock_init(&ubi->volumes_lock);
+	mutex_init(&ubi->fm_mutex);
+	init_rwsem(&ubi->fm_sem);
 
 	ubi_msg("attaching mtd%d to ubi%d", mtd->index, ubi_num);
 
@@ -934,11 +980,17 @@ int ubi_attach_mtd_dev(struct mtd_info *mtd, int ubi_num,
 	if (!ubi->peb_buf)
 		goto out_free;
 
+#ifdef CONFIG_MTD_UBI_FASTMAP
+	ubi->fm_size = ubi_calc_fm_size(ubi);
+	ubi->fm_buf = vzalloc(ubi->fm_size);
+	if (!ubi->fm_buf)
+		goto out_free;
+#endif
 	err = ubi_debugging_init_dev(ubi);
 	if (err)
 		goto out_free;
 
-	err = ubi_attach(ubi);
+	err = ubi_attach(ubi, 0);
 	if (err) {
 		ubi_err("failed to attach mtd%d, error %d", mtd->index, err);
 		goto out_debugging;
@@ -1012,6 +1064,7 @@ out_debugging:
 	ubi_debugging_exit_dev(ubi);
 out_free:
 	vfree(ubi->peb_buf);
+	vfree(ubi->fm_buf);
 	if (ref)
 		put_device(&ubi->dev);
 	else
@@ -1061,7 +1114,11 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway)
 	ubi_assert(ubi_num == ubi->ubi_num);
 	ubi_notify_all(ubi, UBI_VOLUME_REMOVED, NULL);
 	ubi_msg("detaching mtd%d from ubi%d", ubi->mtd->index, ubi_num);
-
+#ifdef CONFIG_MTD_UBI_FASTMAP
+	/* If we don't write a new fastmap at detach time we lose all
+	 * EC updates that have been made since the last written fastmap. */
+	ubi_update_fastmap(ubi);
+#endif
 	/*
 	 * Before freeing anything, we have to stop the background thread to
 	 * prevent it from doing anything on this device while we are freeing.
@@ -1077,12 +1134,14 @@ int ubi_detach_mtd_dev(int ubi_num, int anyway)
 
 	ubi_debugfs_exit_dev(ubi);
 	uif_close(ubi);
+
 	ubi_wl_close(ubi);
 	ubi_free_internal_volumes(ubi);
 	vfree(ubi->vtbl);
 	put_mtd_device(ubi->mtd);
 	ubi_debugging_exit_dev(ubi);
 	vfree(ubi->peb_buf);
+	vfree(ubi->fm_buf);
 	ubi_msg("mtd%d is detached from ubi%d", ubi->mtd->index, ubi->ubi_num);
 	put_device(&ubi->dev);
 	return 0;
@@ -1404,7 +1463,10 @@ MODULE_PARM_DESC(mtd, "MTD devices to attach. Parameter format: mtd=<name|num|pa
 		      "Example 2: mtd=content,1984 mtd=4 - attach MTD device with name \"content\" using VID header offset 1984, and MTD device number 4 with default VID header offset.\n"
 		      "Example 3: mtd=/dev/mtd1,0,25 - attach MTD device /dev/mtd1 using default VID header offset and reserve 25*nand_size_in_blocks/1024 erase blocks for bad block handling.\n"
 		      "\t(e.g. if the NAND *chipset* has 4096 PEB, 100 will be reserved for this UBI device).");
-
+#ifdef CONFIG_MTD_UBI_FASTMAP
+module_param(fm_autoconvert, bool, 0644);
+MODULE_PARM_DESC(fm_autoconvert, "Set this parameter to enable fastmap automatically on images without a fastmap.");
+#endif
 MODULE_VERSION(__stringify(UBI_VERSION));
 MODULE_DESCRIPTION("UBI - Unsorted Block Images");
 MODULE_AUTHOR("Artem Bityutskiy");