kernel.git/fs/jffs2/super.c, branch linux-3.2.y

jffs2: add compr=lzo and compr=zlib options

2011-10-19T14:22:21Z

..to allow forcing of either compression scheme. This will override compiled-in defaults. jffs2_compress is reworked a bit, as the lzo/zlib override shares lots of code w/ the PRIORITY mode. v2: update show_options accordingly. Signed-off-by: Andres Salomon Signed-off-by: Artem Bityutskiy

jffs2: implement mount option parsing and compression overriding

2011-10-19T14:22:20Z

Currently jffs2 has compile-time constants (and .config options) controlling whether or not the various compression/decompression drivers are built in and enabled. This is fine for embedded systems, but it clashes with distribution kernels. Distro kernels tend to turn on everything; this causes OpenFirmware to fall over, as it understands ZLIB-compressed inodes. Booting a kernel that has LZO compression enabled, writing to the boot partition, and then rebooting causes OFW to fail to read the kernel from the filesystem. This is because LZO compression has priority when writing new data to jffs2, if LZO is enabled. This patch adds mount option parsing, and a single supported option ("compr=none"). This adds the flexibility of being able to specify which compressor overrides on a per-superblock basis. For now, we can simply disable compression; additional flexibility coming soon. v2: kill some printks, and implement show_options as suggested by Artem Bityutskiy. Signed-off-by: Andres Salomon Signed-off-by: Artem Bityutskiy

fs: icache RCU free inodes

2011-01-07T06:50:26Z

RCU free the struct inode. This will allow: - Subsequent store-free path walking patch. The inode must be consulted for permissions when walking, so an RCU inode reference is a must. - sb_inode_list_lock to be moved inside i_lock because sb list walkers who want to take i_lock no longer need to take sb_inode_list_lock to walk the list in the first place. This will simplify and optimize locking. - Could remove some nested trylock loops in dcache code - Could potentially simplify things a bit in VM land. Do not need to take the page lock to follow page->mapping. The downsides of this is the performance cost of using RCU. In a simple creat/unlink microbenchmark, performance drops by about 10% due to inability to reuse cache-hot slab objects. As iterations increase and RCU freeing starts kicking over, this increases to about 20%. In cases where inode lifetimes are longer (ie. many inodes may be allocated during the average life span of a single inode), a lot of this cache reuse is not applicable, so the regression caused by this patch is smaller. The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU, however this adds some complexity to list walking and store-free path walking, so I prefer to implement this at a later date, if it is shown to be a win in real situations. I haven't found a regression in any non-micro benchmark so I doubt it will be a problem. Signed-off-by: Nick Piggin

convert get_sb_mtd() users to ->mount()

2010-10-29T08:16:26Z

Signed-off-by: Al Viro

BKL: Remove BKL from jffs2

2010-10-04T19:10:50Z

The BKL is only used in put_super, fill_super and remount_fs that are all three protected by the superblocks s_umount rw_semaphore. Therefore it is safe to remove the BKL entirely. Signed-off-by: Arnd Bergmann Cc: David Woodhouse

BKL: Explicitly add BKL around get_sb/fill_super

2010-10-04T19:10:10Z

This patch is a preparation necessary to remove the BKL from do_new_mount(). It explicitly adds calls to lock_kernel()/unlock_kernel() around get_sb/fill_super operations for filesystems that still uses the BKL. I've read through all the code formerly covered by the BKL inside do_kern_mount() and have satisfied myself that it doesn't need the BKL any more. do_kern_mount() is already called without the BKL when mounting the rootfs and in nfsctl. do_kern_mount() calls vfs_kern_mount(), which is called from various places without BKL: simple_pin_fs(), nfs_do_clone_mount() through nfs_follow_mountpoint(), afs_mntpt_do_automount() through afs_mntpt_follow_link(). Both later functions are actually the filesystems follow_link inode operation. vfs_kern_mount() is calling the specified get_sb function and lets the filesystem do its job by calling the given fill_super function. Therefore I think it is safe to push down the BKL from the VFS to the low-level filesystems get_sb/fill_super operation. [arnd: do not add the BKL to those file systems that already don't use it elsewhere] Signed-off-by: Jan Blunck Signed-off-by: Arnd Bergmann Cc: Matthew Wilcox Cc: Christoph Hellwig

convert remaining ->clear_inode() to ->evict_inode()

2010-08-09T20:48:37Z

Signed-off-by: Al Viro

jffs2: Stop triggering block erases from jffs2_write_super()

2010-05-19T16:16:11Z

This is the culmination of this sequence of patches. By moving the block erasing from jffs2_write_super() into the GC code, we avoid huge latencies on unmount where it waits for _all_ pending blocks to be erased, and we allow better control for time-critical tasks by stopping the GC thread. Signed-off-by: Joakim Tjernlund Signed-off-by: David Woodhouse

jffs2: Require jffs2_garbage_collect_trigger() to be called with lock held

2010-05-19T16:10:22Z

We're about to call this from a bunch of places which already hold c->erase_completion_lock, so add an assertion and change its existing callers to do the same. Signed-off-by: David Woodhouse

const: mark remaining export_operations const

2009-09-22T14:17:24Z

Signed-off-by: Alexey Dobriyan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds