UBI: power cut emulation for testing (50269067) · Commits · e / devices / android_kernel_samsung_universal8895

drivers/mtd/ubi/debug.c

+87 −2

Original line number	Original line	Diff line number	Diff line
	@@ -263,7 +263,7 @@ static ssize_t dfs_file_read(struct file file, char __user user_buf,
	struct dentry *dent = file->f_path.dentry;		struct dentry *dent = file->f_path.dentry;
	struct ubi_device *ubi;		struct ubi_device *ubi;
	struct ubi_debug_info *d;		struct ubi_debug_info *d;
	char buf[3];		char buf[8];
	int val;		int val;

	ubi = ubi_get_device(ubi_num);		ubi = ubi_get_device(ubi_num);
	@@ -283,6 +283,22 @@ static ssize_t dfs_file_read(struct file file, char __user user_buf,
	val = d->emulate_bitflips;		val = d->emulate_bitflips;
	else if (dent == d->dfs_emulate_io_failures)		else if (dent == d->dfs_emulate_io_failures)
	val = d->emulate_io_failures;		val = d->emulate_io_failures;
			else if (dent == d->dfs_emulate_power_cut) {
			snprintf(buf, sizeof(buf), "%u\n", d->emulate_power_cut);
			count = simple_read_from_buffer(user_buf, count, ppos,
			buf, strlen(buf));
			goto out;
			} else if (dent == d->dfs_power_cut_min) {
			snprintf(buf, sizeof(buf), "%u\n", d->power_cut_min);
			count = simple_read_from_buffer(user_buf, count, ppos,
			buf, strlen(buf));
			goto out;
			} else if (dent == d->dfs_power_cut_max) {
			snprintf(buf, sizeof(buf), "%u\n", d->power_cut_max);
			count = simple_read_from_buffer(user_buf, count, ppos,
			buf, strlen(buf));
			goto out;
			}
	else {		else {
	count = -EINVAL;		count = -EINVAL;
	goto out;		goto out;
	@@ -311,7 +327,7 @@ static ssize_t dfs_file_write(struct file file, const char __user user_buf,
	struct ubi_device *ubi;		struct ubi_device *ubi;
	struct ubi_debug_info *d;		struct ubi_debug_info *d;
	size_t buf_size;		size_t buf_size;
	char buf[8];		char buf[8] = {0};
	int val;		int val;

	ubi = ubi_get_device(ubi_num);		ubi = ubi_get_device(ubi_num);
	@@ -325,6 +341,21 @@ static ssize_t dfs_file_write(struct file file, const char __user user_buf,
	goto out;		goto out;
	}		}

			if (dent == d->dfs_power_cut_min) {
			if (kstrtouint(buf, 0, &d->power_cut_min) != 0)
			count = -EINVAL;
			goto out;
			} else if (dent == d->dfs_power_cut_max) {
			if (kstrtouint(buf, 0, &d->power_cut_max) != 0)
			count = -EINVAL;
			goto out;
			} else if (dent == d->dfs_emulate_power_cut) {
			if (kstrtoint(buf, 0, &val) != 0)
			count = -EINVAL;
			d->emulate_power_cut = val;
			goto out;
			}

	if (buf[0] == '1')		if (buf[0] == '1')
	val = 1;		val = 1;
	else if (buf[0] == '0')		else if (buf[0] == '0')
	@@ -438,6 +469,27 @@ int ubi_debugfs_init_dev(struct ubi_device *ubi)
	goto out_remove;		goto out_remove;
	d->dfs_emulate_io_failures = dent;		d->dfs_emulate_io_failures = dent;

			fname = "tst_emulate_power_cut";
			dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
			&dfs_fops);
			if (IS_ERR_OR_NULL(dent))
			goto out_remove;
			d->dfs_emulate_power_cut = dent;

			fname = "tst_emulate_power_cut_min";
			dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
			&dfs_fops);
			if (IS_ERR_OR_NULL(dent))
			goto out_remove;
			d->dfs_power_cut_min = dent;

			fname = "tst_emulate_power_cut_max";
			dent = debugfs_create_file(fname, S_IWUSR, d->dfs_dir, (void *)ubi_num,
			&dfs_fops);
			if (IS_ERR_OR_NULL(dent))
			goto out_remove;
			d->dfs_power_cut_max = dent;

	return 0;		return 0;

	out_remove:		out_remove:
	@@ -458,3 +510,36 @@ void ubi_debugfs_exit_dev(struct ubi_device *ubi)
	if (IS_ENABLED(CONFIG_DEBUG_FS))		if (IS_ENABLED(CONFIG_DEBUG_FS))
	debugfs_remove_recursive(ubi->dbg.dfs_dir);		debugfs_remove_recursive(ubi->dbg.dfs_dir);
	}		}

			/**
			* ubi_dbg_power_cut - emulate a power cut if it is time to do so
			* @ubi: UBI device description object
			* @caller: Flags set to indicate from where the function is being called
			*
			* Returns non-zero if a power cut was emulated, zero if not.
			*/
			int ubi_dbg_power_cut(struct ubi_device *ubi, int caller)
			{
			unsigned int range;

			if ((ubi->dbg.emulate_power_cut & caller) == 0)
			return 0;

			if (ubi->dbg.power_cut_counter == 0) {
			ubi->dbg.power_cut_counter = ubi->dbg.power_cut_min;

			if (ubi->dbg.power_cut_max > ubi->dbg.power_cut_min) {
			range = ubi->dbg.power_cut_max - ubi->dbg.power_cut_min;
			ubi->dbg.power_cut_counter += prandom_u32() % range;
			}
			return 0;
			}

			ubi->dbg.power_cut_counter--;
			if (ubi->dbg.power_cut_counter)
			return 0;

			ubi_msg(ubi, "XXXXXXXXXXXXXXX emulating a power cut XXXXXXXXXXXXXXXX");
			ubi_ro_mode(ubi);
			return 1;
			}

drivers/mtd/ubi/debug.h

+2 −0

Original line number	Original line	Diff line number	Diff line
	@@ -137,4 +137,6 @@ static inline void ubi_enable_dbg_chk_fastmap(struct ubi_device *ubi)
	{		{
	ubi->dbg.chk_fastmap = 1;		ubi->dbg.chk_fastmap = 1;
	}		}

			int ubi_dbg_power_cut(struct ubi_device *ubi, int caller);
	#endif /* !__UBI_DEBUG_H__ */		#endif /* !__UBI_DEBUG_H__ */

drivers/mtd/ubi/io.c

+6 −0

Original line number	Original line	Diff line number	Diff line
	@@ -859,6 +859,9 @@ int ubi_io_write_ec_hdr(struct ubi_device *ubi, int pnum,
	if (err)		if (err)
	return err;		return err;

			if (ubi_dbg_power_cut(ubi, POWER_CUT_EC_WRITE))
			return -EROFS;

	err = ubi_io_write(ubi, ec_hdr, pnum, 0, ubi->ec_hdr_alsize);		err = ubi_io_write(ubi, ec_hdr, pnum, 0, ubi->ec_hdr_alsize);
	return err;		return err;
	}		}
	@@ -1106,6 +1109,9 @@ int ubi_io_write_vid_hdr(struct ubi_device *ubi, int pnum,
	if (err)		if (err)
	return err;		return err;

			if (ubi_dbg_power_cut(ubi, POWER_CUT_VID_WRITE))
			return -EROFS;

	p = (char *)vid_hdr - ubi->vid_hdr_shift;		p = (char *)vid_hdr - ubi->vid_hdr_shift;
	err = ubi_io_write(ubi, p, pnum, ubi->vid_hdr_aloffset,		err = ubi_io_write(ubi, p, pnum, ubi->vid_hdr_aloffset,
	ubi->vid_hdr_alsize);		ubi->vid_hdr_alsize);

drivers/mtd/ubi/ubi.h

+25 −0

Original line number	Original line	Diff line number	Diff line
	@@ -151,6 +151,17 @@ enum {
	UBI_BAD_FASTMAP,		UBI_BAD_FASTMAP,
	};		};

			/*
			* Flags for emulate_power_cut in ubi_debug_info
			*
			* POWER_CUT_EC_WRITE: Emulate a power cut when writing an EC header
			* POWER_CUT_VID_WRITE: Emulate a power cut when writing a VID header
			*/
			enum {
			POWER_CUT_EC_WRITE = 0x01,
			POWER_CUT_VID_WRITE = 0x02,
			};

	/**		/**
	* struct ubi_wl_entry - wear-leveling entry.		* struct ubi_wl_entry - wear-leveling entry.
	* @u.rb: link in the corresponding (free/used) RB-tree		* @u.rb: link in the corresponding (free/used) RB-tree
	@@ -360,6 +371,10 @@ struct ubi_wl_entry;
	* @disable_bgt: disable the background task for testing purposes		* @disable_bgt: disable the background task for testing purposes
	* @emulate_bitflips: emulate bit-flips for testing purposes		* @emulate_bitflips: emulate bit-flips for testing purposes
	* @emulate_io_failures: emulate write/erase failures for testing purposes		* @emulate_io_failures: emulate write/erase failures for testing purposes
			* @emulate_power_cut: emulate power cut for testing purposes
			* @power_cut_counter: count down for writes left until emulated power cut
			* @power_cut_min: minimum number of writes before emulating a power cut
			* @power_cut_max: maximum number of writes until emulating a power cut
	* @dfs_dir_name: name of debugfs directory containing files of this UBI device		* @dfs_dir_name: name of debugfs directory containing files of this UBI device
	* @dfs_dir: direntry object of the UBI device debugfs directory		* @dfs_dir: direntry object of the UBI device debugfs directory
	* @dfs_chk_gen: debugfs knob to enable UBI general extra checks		* @dfs_chk_gen: debugfs knob to enable UBI general extra checks
	@@ -368,6 +383,9 @@ struct ubi_wl_entry;
	* @dfs_disable_bgt: debugfs knob to disable the background task		* @dfs_disable_bgt: debugfs knob to disable the background task
	* @dfs_emulate_bitflips: debugfs knob to emulate bit-flips		* @dfs_emulate_bitflips: debugfs knob to emulate bit-flips
	* @dfs_emulate_io_failures: debugfs knob to emulate write/erase failures		* @dfs_emulate_io_failures: debugfs knob to emulate write/erase failures
			* @dfs_emulate_power_cut: debugfs knob to emulate power cuts
			* @dfs_power_cut_min: debugfs knob for minimum writes before power cut
			* @dfs_power_cut_max: debugfs knob for maximum writes until power cut
	*/		*/
	struct ubi_debug_info {		struct ubi_debug_info {
	unsigned int chk_gen:1;		unsigned int chk_gen:1;
	@@ -376,6 +394,10 @@ struct ubi_debug_info {
	unsigned int disable_bgt:1;		unsigned int disable_bgt:1;
	unsigned int emulate_bitflips:1;		unsigned int emulate_bitflips:1;
	unsigned int emulate_io_failures:1;		unsigned int emulate_io_failures:1;
			unsigned int emulate_power_cut:2;
			unsigned int power_cut_counter;
			unsigned int power_cut_min;
			unsigned int power_cut_max;
	char dfs_dir_name[UBI_DFS_DIR_LEN + 1];		char dfs_dir_name[UBI_DFS_DIR_LEN + 1];
	struct dentry *dfs_dir;		struct dentry *dfs_dir;
	struct dentry *dfs_chk_gen;		struct dentry *dfs_chk_gen;
	@@ -384,6 +406,9 @@ struct ubi_debug_info {
	struct dentry *dfs_disable_bgt;		struct dentry *dfs_disable_bgt;
	struct dentry *dfs_emulate_bitflips;		struct dentry *dfs_emulate_bitflips;
	struct dentry *dfs_emulate_io_failures;		struct dentry *dfs_emulate_io_failures;
			struct dentry *dfs_emulate_power_cut;
			struct dentry *dfs_power_cut_min;
			struct dentry *dfs_power_cut_max;
	};		};

	/**		/**