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2009-04-07nilfs2: fix problems of memory allocation in ioctlRyusuke Konishi
This is another patch for fixing the following problems of a memory copy function in nilfs2 ioctl: (1) It tries to allocate 128KB size of memory even for small objects. (2) Though the function repeatedly tries large memory allocations while reducing the size, GFP_NOWAIT flag is not specified. This increases the possibility of system memory shortage. (3) During the retries of (2), verbose warnings are printed because _GFP_NOWARN flag is not used for the kmalloc calls. The first patch was still doing large allocations by kmalloc which are repeatedly tried while reducing the size. Andi Kleen told me that using copy_from_user for large memory is not good from the viewpoint of preempt latency: On Fri, 12 Dec 2008 21:24:11 +0100, Andi Kleen <andi@firstfloor.org> wrote: > > In the current interface, each data item is copied twice: one is to > > the allocated memory from user space (via copy_from_user), and another > > For such large copies it is better to use multiple smaller (e.g. 4K) > copy user, that gives better real time preempt latencies. Each cfu has a > cond_resched(), but only one, not multiple times in the inner loop. He also advised me that: On Sun, 14 Dec 2008 16:13:27 +0100, Andi Kleen <andi@firstfloor.org> wrote: > Better would be if you could go to PAGE_SIZE. order 0 allocations > are typically the fastest / least likely to stall. > > Also in this case it's a good idea to use __get_free_pages() > directly, kmalloc tends to be become less efficient at larger > sizes. For the function in question, the size of buffer memory can be reduced since the buffer is repeatedly used for a number of small objects. On the other hand, it may incur large preempt latencies for larger buffer because a copy_from_user (and a copy_to_user) was applied only once each cycle. With that, this revision uses the order 0 allocations with __get_free_pages() to fix the original problems. Cc: Andi Kleen <andi@firstfloor.org> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: update makefile and KconfigRyusuke Konishi
This adds a Makefile for the nilfs2 file system, and updates the makefile and Kconfig file in the file system directory. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: ioctl operationsKoji Sato
This adds userland interface implemented with ioctl. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: block cache for garbage collectionRyusuke Konishi
This adds the cache of on-disk blocks to be moved in garbage collection. The disk blocks are held with dummy inodes (called gcinodes), and this file provides lookup function of the dummy inodes, and their buffer read function. Signed-off-by: Seiji Kihara <kihara.seiji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Yoshiji Amagai <amagai.yoshiji@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: another dat for garbage collectionRyusuke Konishi
NILFS2 uses another DAT inode during garbage collection to ensure atomicity and consistency of the DAT in the transient state. This twin inode is called GCDAT. This adds functions to initialize the GCDAT and to switch page caches and B-tree node caches between these two inodes. Signed-off-by: Seiji Kihara <kihara.seiji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Yoshiji Amagai <amagai.yoshiji@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: recovery functionsRyusuke Konishi
This adds recovery function on mount. Usually the recovery is achieved by just finding the latest super root. When logs without checkpoints were appended for data sync operations after the latest super root, the recovery function will perform roll forwarding and reconstruct new log(s) with a super root. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: fix missed-sync issue for do_sync_mapping_range()Ryusuke Konishi
Chris Mason pointed out that there is a missed sync issue in nilfs_writepages(): On Wed, 17 Dec 2008 21:52:55 -0500, Chris Mason wrote: > It looks like nilfs_writepage ignores WB_SYNC_NONE, which is used by > do_sync_mapping_range(). where WB_SYNC_NONE in do_sync_mapping_range() was replaced with WB_SYNC_ALL by Nick's patch (commit: ee53a891f47444c53318b98dac947ede963db400). This fixes the problem by letting nilfs_writepages() write out the log of file data within the range if sync_mode is WB_SYNC_ALL. This involves removal of nilfs_file_aio_write() which was previously needed to ensure O_SYNC sync writes. Cc: Chris Mason <chris.mason@oracle.com> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: segment constructorRyusuke Konishi
This adds the segment constructor (also called log writer). The segment constructor collects dirty buffers for every dirty inode, makes summaries of the buffers, assigns disk block addresses to the buffers, and then submits BIOs for the buffers. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: segment bufferRyusuke Konishi
This adds the segment buffer which is used to constuct logs. [akpm@linux-foundation.org: BIO_RW_SYNC got removed] Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: super block operationsRyusuke Konishi
This adds super block operations for the nilfs2 file system. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: operations for the_nilfs core objectRyusuke Konishi
This adds functions on the_nilfs object, which keeps shared resources and states among a read/write mount and snapshots mounts going individually. the_nilfs is allocated per block device; it is created when user first mount a snapshot or a read/write mount on the device, then it is reused for successive mounts. It will be freed when all mount instances on the device are detached. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: pathname operationsRyusuke Konishi
This adds pathname operations, most of which comes from the ext2 file system. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: directory entry operationsYoshiji Amagai
This adds directory handling functions, most of which comes from the ext2 file system. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Yoshiji Amagai <amagai.yoshiji@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: file operationsRyusuke Konishi
This adds primitives for regular file handling. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: inode operationsRyusuke Konishi
This adds inode level operations of the nilfs2 file system. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: segment usage fileKoji Sato
This adds a meta data file which stores the allocation state of segments. [konishi.ryusuke@lab.ntt.co.jp: fix wrong counting of checkpoints and dirty segments] Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: checkpoint fileKoji Sato
This adds a meta data file which holds checkpoint entries in its data blocks. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: inode map fileRyusuke Konishi
This adds a meta data file which stores on-disk inodes in its data blocks. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Yoshiji Amagai <amagai.yoshiji@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: disk address translatorKoji Sato
This adds the disk address translation file (DAT) whose primary function is to convert virtual disk block numbers to actual disk block numbers. The virtual block numbers of NILFS are associated with checkpoint generation numbers, and this file also provides functions to manage the lifetime information of each virtual block number. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: persistent object allocatorRyusuke Konishi
This adds common functions to allocate or deallocate entries with bitmaps on a meta data file. This feature is used by the DAT and ifile. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Yoshiji Amagai <amagai.yoshiji@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: meta data fileRyusuke Konishi
This adds the meta data file, which serves common buffer functions to the DAT, sufile, cpfile, ifile, and so forth. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: buffer and page operationsRyusuke Konishi
This adds common routines for buffer/page operations used in B-tree node caches, meta data files, or segment constructor (log writer). NILFS uses copy functions for buffers and pages due to the following reasons: 1) Relocation required for COW Since NILFS changes address of on-disk blocks, moving buffers in page cache is needed for the buffers which are not addressed by a file offset. If buffer size is smaller than page size, this involves partial copy of pages. 2) Freezing mmapped pages NILFS calculates checksums for each log to ensure its validity. If page data changes after the checksum calculation, this validity check will not work correctly. To avoid this failure for mmaped pages, NILFS freezes their data by copying. 3) Copy-on-write for DAT pages NILFS makes clones of DAT page caches in a copy-on-write manner during GC processes, and this ensures atomicity and consistency of the DAT in the transient state. In addition, NILFS uses two obsolete functions, nilfs_mark_buffer_dirty() and nilfs_clear_page_dirty() respectively. * nilfs_mark_buffer_dirty() was required to avoid NULL pointer dereference faults: Since the page cache of B-tree node pages or data page cache of pseudo inodes does not have a valid mapping->host, calling mark_buffer_dirty() for their buffers causes the fault; it calls __mark_inode_dirty(NULL) through __set_page_dirty(). * nilfs_clear_page_dirty() was needed in the two cases: 1) For B-tree node pages and data pages of the dat/gcdat, NILFS2 clears page dirty flags when it copies back pages from the cloned cache (gcdat->{i_mapping,i_btnode_cache}) to its original cache (dat->{i_mapping,i_btnode_cache}). 2) Some B-tree operations like insertion or deletion may dispose buffers in dirty state, and this needs to cancel the dirty state of their pages. clear_page_dirty_for_io() caused faults because it does not clear the dirty tag on the page cache. Signed-off-by: Seiji Kihara <kihara.seiji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: B-tree node cacheRyusuke Konishi
This adds routines for B-tree node buffers. Signed-off-by: Seiji Kihara <kihara.seiji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: direct block mappingKoji Sato
This adds block mappings using direct pointers which are stored in the i_bmap array of inode. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: B-tree based block mappingKoji Sato
This adds declarations and functions of NILFS2 B-tree. Two variants are integrated in the NILFS2 B-tree. The B-tree for the most files points to the child nodes or data blocks with virtual block addresses, whereas the B-tree of the DAT uses actual block addresses. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: integrated block mappingKoji Sato
This adds structures and operations for the block mapping (bmap for short). NILFS2 uses direct mappings for short files or B-tree based mappings for longer files. Every on-disk data block is held with inodes and managed through this block mapping. The nilfs_bmap structure and a set of functions here provide this capability to the NILFS2 inode. [penberg@cs.helsinki.fi: remove a bunch of bmap wrapper macros] [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: add inode and other major structuresRyusuke Konishi
This adds the following common structures of the NILFS2 file system. * nilfs_inode_info structure: gives on-memory inode. * nilfs_sb_info structure: keeps per-mount state and a special inode for the ifile. This structure is attached to the super_block structure. * the_nilfs structure: keeps shared state and locks among a read/write mount and snapshot mounts. This keeps special inodes for the sufile, cpfile, dat, and another dat inode used during GC (gcdat). This also has a hash table of dummy inodes to cache disk blocks during GC (gcinodes). * nilfs_transaction_info structure: keeps per task state while nilfs is writing logs or doing indivisible inode or namespace operations. This structure is used to identify context during log making and store nest level of the lock which ensures atomicity of file system operations. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: disk format and userland interfaceKoji Sato
This adds a header file which specifies the on-disk format and ioctl interface of the nilfs2 file system. Signed-off-by: Koji Sato <sato.koji@lab.ntt.co.jp> Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07nilfs2: add documentRyusuke Konishi
This adds a document describing the features, mount options, userland tools, usage, disk format, and related URLs for the nilfs2 file system. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07dma-mapping: update the old macro DMA_nBIT_MASK related documentationsYang Hongyang
Update the old macro DMA_nBIT_MASK related documentations Signed-off-by: Yang Hongyang<yanghy@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07dma-mapping: replace all DMA_24BIT_MASK macro with DMA_BIT_MASK(24)Yang Hongyang
Replace all DMA_24BIT_MASK macro with DMA_BIT_MASK(24) Signed-off-by: Yang Hongyang<yanghy@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07dma-mapping: replace all DMA_28BIT_MASK macro with DMA_BIT_MASK(28)Yang Hongyang
Replace all DMA_28BIT_MASK macro with DMA_BIT_MASK(28) Signed-off-by: Yang Hongyang<yanghy@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07dma-mapping: replace all DMA_30BIT_MASK macro with DMA_BIT_MASK(30)Yang Hongyang
Replace all DMA_30BIT_MASK macro with DMA_BIT_MASK(30) Signed-off-by: Yang Hongyang<yanghy@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07dma-mapping: replace all DMA_31BIT_MASK macro with DMA_BIT_MASK(31)Yang Hongyang
Replace all DMA_31BIT_MASK macro with DMA_BIT_MASK(31) Signed-off-by: Yang Hongyang<yanghy@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07dma-mapping: replace all DMA_32BIT_MASK macro with DMA_BIT_MASK(32)Yang Hongyang
Replace all DMA_32BIT_MASK macro with DMA_BIT_MASK(32) Signed-off-by: Yang Hongyang<yanghy@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07dma-mapping: replace all DMA_39BIT_MASK macro with DMA_BIT_MASK(39)Yang Hongyang
Replace all DMA_39BIT_MASK macro with DMA_BIT_MASK(39) Signed-off-by: Yang Hongyang<yanghy@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07dma-mapping: replace all DMA_40BIT_MASK macro with DMA_BIT_MASK(40)Yang Hongyang
Replace all DMA_40BIT_MASK macro with DMA_BIT_MASK(40) Signed-off-by: Yang Hongyang<yanghy@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07dma-mapping: replace all DMA_48BIT_MASK macro with DMA_BIT_MASK(48)Yang Hongyang
Replace all DMA_48BIT_MASK macro with DMA_BIT_MASK(48) Signed-off-by: Yang Hongyang<yanghy@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07dma-mapping: replace all DMA_64BIT_MASK macro with DMA_BIT_MASK(64)Yang Hongyang
Replace all DMA_64BIT_MASK macro with DMA_BIT_MASK(64) Signed-off-by: Yang Hongyang<yanghy@cn.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07fs/romfs: return f_fsid for statfs(2)Coly Li
Make romfs return f_fsid info for statfs(2). Signed-off-by: Coly Li <coly.li@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07namespaces: mqueue namespace: adapt sysctlSerge E. Hallyn
Largely inspired from ipc/ipc_sysctl.c. This patch isolates the mqueue sysctl stuff in its own file. [akpm@linux-foundation.org: build fix] Signed-off-by: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Nadia Derbey <Nadia.Derbey@bull.net> Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07namespaces: ipc namespaces: implement support for posix msqueuesSerge E. Hallyn
Implement multiple mounts of the mqueue file system, and link it to usage of CLONE_NEWIPC. Each ipc ns has a corresponding mqueuefs superblock. When a user does clone(CLONE_NEWIPC) or unshare(CLONE_NEWIPC), the unshare will cause an internal mount of a new mqueuefs sb linked to the new ipc ns. When a user does 'mount -t mqueue mqueue /dev/mqueue', he mounts the mqueuefs superblock. Posix message queues can be worked with both through the mq_* system calls (see mq_overview(7)), and through the VFS through the mqueue mount. Any usage of mq_open() and friends will work with the acting task's ipc namespace. Any actions through the VFS will work with the mqueuefs in which the file was created. So if a user doesn't remount mqueuefs after unshare(CLONE_NEWIPC), mq_open("/ab") will not be reflected in "ls /dev/mqueue". If task a mounts mqueue for ipc_ns:1, then clones task b with a new ipcns, ipcns:2, and then task a is the last task in ipc_ns:1 to exit, then (1) ipc_ns:1 will be freed, (2) it's superblock will live on until task b umounts the corresponding mqueuefs, and vfs actions will continue to succeed, but (3) sb->s_fs_info will be NULL for the sb corresponding to the deceased ipc_ns:1. To make this happen, we must protect the ipc reference count when a) a task exits and drops its ipcns->count, since it might be dropping it to 0 and freeing the ipcns b) a task accesses the ipcns through its mqueuefs interface, since it bumps the ipcns refcount and might race with the last task in the ipcns exiting. So the kref is changed to an atomic_t so we can use atomic_dec_and_lock(&ns->count,mq_lock), and every access to the ipcns through ns = mqueuefs_sb->s_fs_info is protected by the same lock. Signed-off-by: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07namespaces: mqueue ns: move mqueue_mnt into struct ipc_namespaceSerge E. Hallyn
Move mqueue vfsmount plus a few tunables into the ipc_namespace struct. The CONFIG_IPC_NS boolean and the ipc_namespace struct will serve both the posix message queue namespaces and the SYSV ipc namespaces. The sysctl code will be fixed separately in patch 3. After just this patch, making a change to posix mqueue tunables always changes the values in the initial ipc namespace. Signed-off-by: Cedric Le Goater <clg@fr.ibm.com> Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07namespaces: move proc_net_get_sb to a generic fs/super.c helperSerge E. Hallyn
The mqueuefs filesystem will use this helper as well. Proc's main get_sb could also be made to use it, but that will require a bit more rework. Signed-off-by: Serge E. Hallyn <serue@us.ibm.com> Cc: Cedric Le Goater <clg@fr.ibm.com> Cc: Alexey Dobriyan <adobriyan@gmail.com> Cc: "David S. Miller" <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07uvesafb: documentation updateMichal Januszewski
Update the uvesafb documentation to accurately reflect the default options used by the driver. Signed-off-by: Michal Januszewski <spock@gentoo.org> Cc: Krzysztof Helt <krzysztof.h1@poczta.fm> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07fbdev: i.MX31: fix panning, error handling, clean upGuennadi Liakhovetski
1. check for errors returned from clk_get() 2. fix "Unbalanced enable for IRQ 160" 3. fix transmit descriptor handling in panning 4. clean frame buffer on blank - useful for OLED displays 5. formatting clean up Signed-off-by: Guennadi Liakhovetski <lg@denx.de> Cc: Dan Williams <dan.j.williams@intel.com> Cc: Sascha Hauer <s.hauer@pengutronix.de> Cc: Krzysztof Helt <krzysztof.h1@poczta.fm> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07tdfxfb: make use of DDC information about connected monitorKrzysztof Helt
Read DDC information from a connected monitor and use it to select initial mode (if the mode is not specified). Also, use the information to protect against modes outside the monitor specs. Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl> Tested-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07tdfxfb: move I2C functionality into the tdfxfbKrzysztof Helt
The I2C functionality provided by the i2c-voodoo3 driver is moved into the tdfxfb (frame buffer driver for Voodoo3 cards). This way there is no conflict between the i2c driver and the fb driver. The tdfxfb does not make use from the DDC functionality yet but provides all the functionality of the i2c-voodoo3 driver. Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl> Acked-by: Jean Delvare <khali@linux-fr.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07kprobes: support kretprobe and jprobe per-probe disablingMasami Hiramatsu
Add disable/enable_kretprobe() and disable/enable_jprobe(). Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-07kprobes: support per-kprobe disablingMasami Hiramatsu
Add disable_kprobe() and enable_kprobe() to disable/enable kprobes temporarily. disable_kprobe() asynchronously disables probe handlers of specified kprobe. So, after calling it, some handlers can be called at a while. enable_kprobe() enables specified kprobe. aggr_pre_handler and aggr_post_handler check disabled probes. On the other hand aggr_break_handler and aggr_fault_handler don't check it because these handlers will be called while executing pre or post handlers and usually those help error handling. Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Acked-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> Cc: David S. Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>