UBI: amend commentaries (85c6e6e2) · Commits · e / devices / android_kernel_xiaomi_markw

drivers/mtd/ubi/build.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -524,7 +524,7 @@ out_si:
		}

		/**
		* io_init - initialize I/O unit for a given UBI device.
		* io_init - initialize I/O sub-system for a given UBI device.
		* @ubi: UBI device description object
		*
		* If @ubi->vid_hdr_offset or @ubi->leb_start is zero, default offsets are

drivers/mtd/ubi/debug.h

+3 −3

Original line number	Diff line number	Diff line
		@@ -76,21 +76,21 @@ void ubi_dbg_dump_mkvol_req(const struct ubi_mkvol_req *req);
		#endif /* CONFIG_MTD_UBI_DEBUG_MSG */

		#ifdef CONFIG_MTD_UBI_DEBUG_MSG_EBA
		/* Messages from the eraseblock association unit */
		/* Messages from the eraseblock association sub-system */
		#define dbg_eba(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__)
		#else
		#define dbg_eba(fmt, ...) ({})
		#endif

		#ifdef CONFIG_MTD_UBI_DEBUG_MSG_WL
		/* Messages from the wear-leveling unit */
		/* Messages from the wear-leveling sub-system */
		#define dbg_wl(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__)
		#else
		#define dbg_wl(fmt, ...) ({})
		#endif

		#ifdef CONFIG_MTD_UBI_DEBUG_MSG_IO
		/* Messages from the input/output unit */
		/* Messages from the input/output sub-system */
		#define dbg_io(fmt, ...) dbg_msg(fmt, ##__VA_ARGS__)
		#else
		#define dbg_io(fmt, ...) ({})

drivers/mtd/ubi/eba.c

+11 −11

Original line number	Diff line number	Diff line
		@@ -19,20 +19,20 @@
		*/

		/*
		* The UBI Eraseblock Association (EBA) unit.
		* The UBI Eraseblock Association (EBA) sub-system.
		*
		* This unit is responsible for I/O to/from logical eraseblock.
		* This sub-system is responsible for I/O to/from logical eraseblock.
		*
		* Although in this implementation the EBA table is fully kept and managed in
		* RAM, which assumes poor scalability, it might be (partially) maintained on
		* flash in future implementations.
		*
		* The EBA unit implements per-logical eraseblock locking. Before accessing a
		* logical eraseblock it is locked for reading or writing. The per-logical
		* eraseblock locking is implemented by means of the lock tree. The lock tree
		* is an RB-tree which refers all the currently locked logical eraseblocks. The
		* lock tree elements are &struct ubi_ltree_entry objects. They are indexed by
		* (@vol_id, @lnum) pairs.
		* The EBA sub-system implements per-logical eraseblock locking. Before
		* accessing a logical eraseblock it is locked for reading or writing. The
		* per-logical eraseblock locking is implemented by means of the lock tree. The
		* lock tree is an RB-tree which refers all the currently locked logical
		* eraseblocks. The lock tree elements are &struct ubi_ltree_entry objects.
		* They are indexed by (@vol_id, @lnum) pairs.
		*
		* EBA also maintains the global sequence counter which is incremented each
		* time a logical eraseblock is mapped to a physical eraseblock and it is
		@@ -1128,7 +1128,7 @@ out_unlock_leb:
		}

		/**
		* ubi_eba_init_scan - initialize the EBA unit using scanning information.
		* ubi_eba_init_scan - initialize the EBA sub-system using scanning information.
		* @ubi: UBI device description object
		* @si: scanning information
		*
		@@ -1143,7 +1143,7 @@ int ubi_eba_init_scan(struct ubi_device ubi, struct ubi_scan_info si)
		struct ubi_scan_leb *seb;
		struct rb_node *rb;

		dbg_eba("initialize EBA unit");
		dbg_eba("initialize EBA sub-system");

		spin_lock_init(&ubi->ltree_lock);
		mutex_init(&ubi->alc_mutex);
		@@ -1209,7 +1209,7 @@ int ubi_eba_init_scan(struct ubi_device ubi, struct ubi_scan_info si)
		ubi->rsvd_pebs += ubi->beb_rsvd_pebs;
		}

		dbg_eba("EBA unit is initialized");
		dbg_eba("EBA sub-system is initialized");
		return 0;

		out_free:

drivers/mtd/ubi/io.c

+11 −11

Original line number	Diff line number	Diff line
		@@ -20,15 +20,15 @@
		*/

		/*
		* UBI input/output unit.
		* UBI input/output sub-system.
		*
		* This unit provides a uniform way to work with all kinds of the underlying
		* MTD devices. It also implements handy functions for reading and writing UBI
		* headers.
		* This sub-system provides a uniform way to work with all kinds of the
		* underlying MTD devices. It also implements handy functions for reading and
		* writing UBI headers.
		*
		* We are trying to have a paranoid mindset and not to trust to what we read
		* from the flash media in order to be more secure and robust. So this unit
		* validates every single header it reads from the flash media.
		* from the flash media in order to be more secure and robust. So this
		* sub-system validates every single header it reads from the flash media.
		*
		* Some words about how the eraseblock headers are stored.
		*
		@@ -79,11 +79,11 @@
		* 512-byte chunks, we have to allocate one more buffer and copy our VID header
		* to offset 448 of this buffer.
		*
		* The I/O unit does the following trick in order to avoid this extra copy.
		* It always allocates a @ubi->vid_hdr_alsize bytes buffer for the VID header
		* and returns a pointer to offset @ubi->vid_hdr_shift of this buffer. When the
		* VID header is being written out, it shifts the VID header pointer back and
		* writes the whole sub-page.
		* The I/O sub-system does the following trick in order to avoid this extra
		* copy. It always allocates a @ubi->vid_hdr_alsize bytes buffer for the VID
		* header and returns a pointer to offset @ubi->vid_hdr_shift of this buffer.
		* When the VID header is being written out, it shifts the VID header pointer
		* back and writes the whole sub-page.
		*/

		#include <linux/crc32.h>

drivers/mtd/ubi/scan.c

+15 −13

Original line number	Diff line number	Diff line
		@@ -19,9 +19,9 @@
		*/

		/*
		* UBI scanning unit.
		* UBI scanning sub-system.
		*
		* This unit is responsible for scanning the flash media, checking UBI
		* This sub-system is responsible for scanning the flash media, checking UBI
		* headers and providing complete information about the UBI flash image.
		*
		* The scanning information is represented by a &struct ubi_scan_info' object.
		@@ -103,7 +103,7 @@ static int add_to_list(struct ubi_scan_info *si, int pnum, int ec,
		* non-zero if an inconsistency was found and zero if not.
		*
		* Note, UBI does sanity check of everything it reads from the flash media.
		* Most of the checks are done in the I/O unit. Here we check that the
		* Most of the checks are done in the I/O sub-system. Here we check that the
		* information in the VID header is consistent to the information in other VID
		* headers of the same volume.
		*/
		@@ -256,8 +256,8 @@ static int compare_lebs(struct ubi_device ubi, const struct ubi_scan_leb seb,
		* that versions that are close to %0xFFFFFFFF are less then
		* versions that are close to %0.
		*
		* The UBI WL unit guarantees that the number of pending tasks
		* is not greater then %0x7FFFFFFF. So, if the difference
		* The UBI WL sub-system guarantees that the number of pending
		* tasks is not greater then %0x7FFFFFFF. So, if the difference
		* between any two versions is greater or equivalent to
		* %0x7FFFFFFF, there was an overflow and the logical
		* eraseblock with lower version is actually newer then the one
		@@ -645,9 +645,9 @@ void ubi_scan_rm_volume(struct ubi_scan_info si, struct ubi_scan_volume sv)
		*
		* This function erases physical eraseblock 'pnum', and writes the erase
		* counter header to it. This function should only be used on UBI device
		* initialization stages, when the EBA unit had not been yet initialized. This
		* function returns zero in case of success and a negative error code in case
		* of failure.
		* initialization stages, when the EBA sub-system had not been yet initialized.
		* This function returns zero in case of success and a negative error code in
		* case of failure.
		*/
		int ubi_scan_erase_peb(struct ubi_device ubi, const struct ubi_scan_info si,
		int pnum, int ec)
		@@ -687,9 +687,10 @@ out_free:
		* @si: scanning information
		*
		* This function returns a free physical eraseblock. It is supposed to be
		* called on the UBI initialization stages when the wear-leveling unit is not
		* initialized yet. This function picks a physical eraseblocks from one of the
		* lists, writes the EC header if it is needed, and removes it from the list.
		* called on the UBI initialization stages when the wear-leveling sub-system is
		* not initialized yet. This function picks a physical eraseblocks from one of
		* the lists, writes the EC header if it is needed, and removes it from the
		* list.
		*
		* This function returns scanning physical eraseblock information in case of
		* success and an error code in case of failure.
		@@ -764,8 +765,9 @@ static int process_eb(struct ubi_device ubi, struct ubi_scan_info si, int pnum
		return err;
		else if (err) {
		/*
		* FIXME: this is actually duty of the I/O unit to initialize
		* this, but MTD does not provide enough information.
		* FIXME: this is actually duty of the I/O sub-system to
		* initialize this, but MTD does not provide enough
		* information.
		*/
		si->bad_peb_count += 1;
		return 0;