xavi/android_kernel_m2note/fs/squashfs, branch ng-7.1.2

ANDROID: squashfs: Fix endianness issue

2017-06-28T10:07:23+00:00

Code in squashfs_process_blocks was not correctly assigning length. Casting to u16* introduced endianness issues on some architectures. Signed-off-by: Daniel Rosenberg Bug: 35257858 Change-Id: I9efaef4bc531b7469de79cf94738ade2dd6e6a8c

ANDROID: squashfs: Fix signed division issue

2017-06-28T10:07:22+00:00

The value here can change depending on the type that PAGE_SIZE has on a given architecture. To avoid the ensuing signed and unsigned division conversions, we shift instead using PAGE_SHIFT Signed-off-by: Daniel Rosenberg Bug: 35257858 Change-Id: I132cae93abea39390c3f0f91a4b2e026e97ed4c7

ANDROID: Squashfs: fix missing NULL check

2017-04-11T09:00:29+00:00

"Squashfs: refactor page_actor" missed a null check within squashfs_bh_to_actor, as that array may now contain null entries Signed-off-by: Daniel Rosenberg Bug: 35257858 Change-Id: Ia6748af980859237a96f509f35903f722a46fd59

fs/squashfs: change usage of LZ4 to work with new LZ4 version

2017-04-11T09:00:22+00:00

Update fs/squashfs to use the updated functions from the new LZ4 module. Link: http://lkml.kernel.org/r/1486321748-19085-5-git-send-email-4sschmid@informatik.uni-hamburg.de Signed-off-by: Sven Schmidt <4sschmid@informatik.uni-hamburg.de> Cc: Bongkyu Kim Cc: Rui Salvaterra Cc: Sergey Senozhatsky Cc: Greg Kroah-Hartman Cc: Herbert Xu Cc: David S. Miller Cc: Anton Vorontsov Cc: Colin Cross Cc: Kees Cook Cc: Tony Luck Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

Squashfs: optimize reading uncompressed data

2017-04-11T09:00:21+00:00

When dealing with uncompressed data, there is no need to read a whole block (default 128K) to get the desired page: the pages are independent from each others. This patch change the readpages logic so that reading uncompressed data only read the number of pages advised by the readahead algorithm. Moreover, if the page actor contains holes (i.e. pages that are already up-to-date), squashfs skips the buffer_head associated to those pages. This patch greatly improve the performance of random reads for uncompressed files because squashfs only read what is needed. It also reduces the number of unnecessary reads. Signed-off-by: Adrien Schildknecht Change-Id: I9109e431ac180a4e0c65381a3e754a425672d3c0

Squashfs: implement .readpages()

2017-04-11T09:00:21+00:00

Squashfs does not implement .readpages(), so the kernel just repeatedly calls .readpage(). The readpages function tries to pack as much pages as possible in the same page actor so that only 1 read request is issued. Now that the read requests are asynchronous, the kernel can truly prefetch pages using its readahead algorithm. Signed-off-by: Adrien Schildknecht Change-Id: I09590c56876e931acca9070505476a98ab1ca79e

Squashfs: replace buffer_head with BIO

2017-04-11T09:00:20+00:00

The 'll_rw_block' has been deprecated and BIO is now the basic container for block I/O within the kernel. Switching to BIO offers 2 advantages: 1/ It removes synchronous wait for the up-to-date buffers: SquashFS now deals with decompressions/copies asynchronously. Implementing an asynchronous mechanism to read data is needed to efficiently implement .readpages(). 2/ Prior to this patch, merging the read requests entirely depends on the IO scheduler. SquashFS has more information than the IO scheduler about what could be merged. Moreover, merging the reads at the FS level means that we rely less on the IO scheduler. Signed-off-by: Adrien Schildknecht Change-Id: I98cf130f1977d396cdeb1f0617425e208b7d0214

Squashfs: refactor page_actor

2017-04-11T09:00:20+00:00

This patch essentially does 3 things: 1/ Always use an array of page to store the data instead of a mix of buffers and pages. 2/ It is now possible to have 'holes' in a page actor, i.e. NULL pages in the array. When reading a block (default 128K), squashfs tries to grab all the pages covering this block. If a single page is up-to-date or locked, it falls back to using an intermediate buffer to do the read and then copy the pages in the actor. Allowing holes in the page actor remove the need for this intermediate buffer. 3/ Refactor the wrappers to share code that deals with page actors. Signed-off-by: Adrien Schildknecht Change-Id: I73f736611766962857c423320478af8cfab8df38

Squashfs: remove the FILE_CACHE option

2017-04-11T09:00:20+00:00

FILE_DIRECT is working fine and offers faster results and lower memory footprint. Removing FILE_CACHE makes our life easier because we don't have to maintain 2 differents function that does the same thing. Signed-off-by: Adrien Schildknecht Change-Id: I3e68dda86fc5d6e67b7e31635974201948e3c4a7

Squashfs: Add LZ4 compression configuration option

2017-04-11T09:00:19+00:00

Add the glue code, and also update the documentation. Signed-off-by: Phillip Lougher Change-Id: I47b7b1777547d48f6924e6bd2be3d865b438b617