kernel.git/drivers/mtd/ubi/io.c, branch linux-2.6.37.y

UBI: fix corrupted PEB detection for NOR flash

2010-12-03T13:49:21Z

My new shiny code for corrupted PEB detection has NOR specific bug. We tread PEB as corrupted and preserve it, if 1. EC header is OK. 2. VID header is corrupted. 3. data area is not "all 0xFFs" In case of NOR we have 'nor_erase_prepare()' quirk, which invalidates the headers before erasing the PEB. And we invalidate first the VID header, and then the EC header. So if a power cut happens after we have invalidated the VID header, but before we have invalidated the EC header, we end up with a PEB which satisfies the above 3 conditions, and the scanning code will treat it as corrupted, and will print scary warnings, wrongly. This patch fixes the issue by firt invalidating the EC header, then invalidating the VID header. In case of power cut inbetween, we still just lose the EC header, and UBI can deal with this situation gracefully. Thanks to Anatolij Gustschin for tracking this down. Signed-off-by: Artem Bityutskiy Reported-by: Anatolij Gustschin Tested-by: Anatolij Gustschin

UBI: make check_pattern function non-static

2010-10-19T14:19:57Z

This patch turns static function 'check_pattern()' into a non-static 'ubi_check_pattern()'. This is just a preparation for the chages which are coming in the next patches. Signed-off-by: Artem Bityutskiy

UBI: handle bit-flips when no header found

2010-10-19T14:19:56Z

Currently UBI has one small flaw - when we read EC or VID header, but find only 0xFF bytes, we return UBI_IO_FF and do not report whether we had bit-flips or not. In case of the VID header, the scanning code adds this PEB to the free list, even though there were bit-flips. Imagine the following situation: we start writing VID header to a PEB and have a power cut, so the PEB becomes unstable. When we scan and read the PEB, we get a bit-flip. Currently, UBI would just ignore this and treat the PEB as free. This patch changes UBI behavior and now UBI will schedule this PEB for erasure. Signed-off-by: Artem Bityutskiy

UBI: remove duplicate IO error codes

2010-10-19T14:19:56Z

The 'UBI_IO_PEB_EMPTY' and 'UBI_IO_PEB_FREE' are essentially the same and mean that there are only 0xFF bytes instead of headers. Simplify UBI a little by turning them into a single 'UBI_IO_FF' error code. Also, stop maintaining commentaries in 'ubi_io_read_vid_hdr()' which are almost identical to commentaries in 'ubi_io_read_ec_hdr()'. Signed-off-by: Artem Bityutskiy

UBI: rename IO error code

2010-10-19T14:19:56Z

Rename UBI_IO_BAD_HDR_READ into UBI_IO_BAD_HDR_EBADMSG which is presumably more self-documenting and readable. Indeed, the '_READ' suffix does not tell much and even confuses, while '_EBADMSG' tells about uncorrectable ECC error, because we use -EBADMSG all over the place to represent ECC errors. Signed-off-by: Artem Bityutskiy

UBI: fix error message and compilation warnings

2010-06-14T05:47:49Z

Fix the followong compilation warnings introduced by commit 095751a6e0838a712393a74eb0b7b6559dbdbe81: drivers/mtd/ubi/scan.c: In function 'check_what_we_have': drivers/mtd/ubi/scan.c:960: warning: passing argument 1 of 'get_random_bytes' discards qualifiers from pointer target type Fix the following compilation warnings introduced by commit 1a49af2ca019dcb4614c32f832bbcb814b61409c: drivers/mtd/ubi/io.c: In function 'ubi_io_read': drivers/mtd/ubi/io.c:153: warning: initialization makes integer from pointer without a cast drivers/mtd/ubi/io.c:170: warning: format '%s' expects type 'char *', but argument 5 has type 'int' drivers/mtd/ubi/io.c:177: warning: format '%zd' expects type 'signed size_t', but argument 7 has type 'int' drivers/mtd/ubi/io.c:177: warning: too many arguments for format Also, amend the ECC error code string and add brackets and whitespace there - this should make the message readable. Reported-by: Stephen Rothwell Signed-off-by: Artem Bityutskiy

UBI: improve ECC error message

2010-06-11T14:23:37Z

ECC errors are quite typical errors on NAND, so it is worth improving the UBI message and print something like ubi_io_read: error -74 (ECC error) while reading 4096 bytes from PEB 1:4 ... rather than ubi_io_read: error -74 while reading 4096 bytes from PEB 1:4 ... Signed-off-by: Artem Bityutskiy

UBI: introduce a new IO return code

2010-06-04T08:30:42Z

This patch introduces the %UBI_IO_BAD_HDR_READ return code for the I/O level function. We will use this code in order to distinguish between "corrupted header possibly because this is non-ubi data" and "corrupted header possibly because of real data corruption and ECC error". So far this patch does not introduce any functional change, just a preparation. This patch is pased on a patch from Sebastian Andrzej Siewior Signed-off-by: Artem Bityutskiy Reviewed-by: Sebastian Andrzej Siewior Tested-by: Sebastian Andrzej Siewior

UBI: simplify IO error codes

2010-06-04T08:30:42Z

We do not really need 2 separate error codes for indicating bad VID and bad EC headers (UBI_IO_BAD_EC_HDR, UBI_IO_BAD_VID_HDR), it is enough to have only one UBI_IO_BAD_HDR return code. This patch does not introduce any functional change, only some code simplification. Signed-off-by: Artem Bityutskiy Reviewed-by: Sebastian Andrzej Siewior Tested-by: Sebastian Andrzej Siewior

UBI: misc comment fixes

2010-05-07T05:33:32Z

Signed-off-by: Shinya Kuribayashi Signed-off-by: Artem Bityutskiy