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2010-08-18hostfs ->follow_link() brainoAl Viro
we want the assignment to err done inside the if () to be visible after it, so (re)declaring err inside if () body is wrong. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-18hostfs: dumb (and usually harmless) tpyo - strncpy instead of strlcpyAl Viro
... not harmless in this case - we have a string in the end of buffer already. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09try to get rid of races in hostfs open()Al Viro
In case of mode mismatch, do *not* blindly close the descriptor another openers might be using right now. Open the underlying file with currently sufficient mode, then * if current mode has grown so that it's sufficient for us now, just close our new fd * if current mode has grown and our fd is *not* enough to cover it, close and repeat. * otherwise, install our fd if the file hadn't been opened at all or dup2() our fd over the current one (and close our fd). Critical section is protected by mutex; yes, system-wide. All we do under it is a bunch of comparison and maybe an overwriting dup2() on host. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09leak in hostfs_unlink()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09hostfs: fix races in dentry_name() and inode_name()Al Viro
calculating size, then doing allocation, then filling the path is a Bad Idea(tm), since the ancestors can be renamed, leading to buffer overrun. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09hostfs: sanitize symlinksAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09hostfs: get rid of inode_dentry_name()Al Viro
it's equivalent to dentry_name() anyway Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09hostfs: get rid of file_type(), fold init_inode()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09switch stat_file() to passing a single struct rather than fsckloads of pointersAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09hostfs: pass pathname to init_inode()Al Viro
We will calculate it in all callers anyway, so there's no need to duplicate that inside. Moreover, that way we lose all failure exits in init_inode(), so it doesn't need to return anything. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09get rid of hostfs_read_inode()Al Viro
There are only two call sites; in one (hostfs_iget()) it's actually a no-op and in another (fill_super()) it's easier to expand the damn thing and use what we know about its arguments to simplify it. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09hostfs: don't keep a field in each inode when we are using it only in rootAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09stop icache pollution in hostfs, switch to ->evict_inode()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09remove inode_setattrChristoph Hellwig
Replace inode_setattr with opencoded variants of it in all callers. This moves the remaining call to vmtruncate into the filesystem methods where it can be replaced with the proper truncate sequence. In a few cases it was obvious that we would never end up calling vmtruncate so it was left out in the opencoded variant: spufs: explicitly checks for ATTR_SIZE earlier btrfs,hugetlbfs,logfs,dlmfs: explicitly clears ATTR_SIZE earlier ufs: contains an opencoded simple_seattr + truncate that sets the filesize just above In addition to that ncpfs called inode_setattr with handcrafted iattrs, which allowed to trim down the opencoded variant. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09Deal with missing exports for hostfsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-05-27drop unused dentry argument to ->fsyncChristoph Hellwig
Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2009-06-30hostfs: set maximum filesize in superblock for proper LFS supportWolfgang Illmeyer
Maximum file size for hostfs mounts defaults to 2GB, so bigger files cannot be read/written through hostfs. This patch initializes the maximum file size to MAX_LFS_SIZE. Addresses http://bugzilla.kernel.org/show_bug.cgi?id=13531 Signed-off-by: Wolfgang Illmeyer <wolfgang@illmeyer.com> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-03-27constify dentry_operations: misc filesystemsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-04fs: symlink write_begin allocation context fixNick Piggin
With the write_begin/write_end aops, page_symlink was broken because it could no longer pass a GFP_NOFS type mask into the point where the allocations happened. They are done in write_begin, which would always assume that the filesystem can be entered from reclaim. This bug could cause filesystem deadlocks. The funny thing with having a gfp_t mask there is that it doesn't really allow the caller to arbitrarily tinker with the context in which it can be called. It couldn't ever be GFP_ATOMIC, for example, because it needs to take the page lock. The only thing any callers care about is __GFP_FS anyway, so turn that into a single flag. Add a new flag for write_begin, AOP_FLAG_NOFS. Filesystems can now act on this flag in their write_begin function. Change __grab_cache_page to accept a nofs argument as well, to honour that flag (while we're there, change the name to grab_cache_page_write_begin which is more instructive and does away with random leading underscores). This is really a more flexible way to go in the end anyway -- if a filesystem happens to want any extra allocations aside from the pagecache ones in ints write_begin function, it may now use GFP_KERNEL (rather than GFP_NOFS) for common case allocations (eg. ocfs2_alloc_write_ctxt, for a random example). [kosaki.motohiro@jp.fujitsu.com: fix ubifs] [kosaki.motohiro@jp.fujitsu.com: fix fuse] Signed-off-by: Nick Piggin <npiggin@suse.de> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Cc: <stable@kernel.org> [2.6.28.x] Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> [ Cleaned up the calling convention: just pass in the AOP flags untouched to the grab_cache_page_write_begin() function. That just simplifies everybody, and may even allow future expansion of the logic. - Linus ] Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-19hostfs: fix a duplicated global function nameWANG Cong
fs/hostfs/hostfs_user.c defines do_readlink() as non-static, and so does fs/xfs/linux-2.6/xfs_ioctl.c when CONFIG_XFS_DEBUG=y. So rename do_readlink() in hostfs to hostfs_do_readlink(). I think it's better if XFS guys will also rename their do_readlink(), it's not necessary to use such a general name. Signed-off-by: WANG Cong <wangcong@zeuux.org> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-10-21[PATCH] introduce fmode_t, do annotationsAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26[PATCH] sanitize ->permission() prototypeAl Viro
* kill nameidata * argument; map the 3 bits in ->flags anybody cares about to new MAY_... ones and pass with the mask. * kill redundant gfs2_iop_permission() * sanitize ecryptfs_permission() * fix remaining places where ->permission() instances might barf on new MAY_... found in mask. The obvious next target in that direction is permission(9) folded fix for nfs_permission() breakage from Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-02-09UML: fix hostfs buildJiri Kosina
/home/bunk/linux/kernel-2.6/git/linux-2.6/fs/hostfs/hostfs_kern.c: In function 'hostfs_show_options': /home/bunk/linux/kernel-2.6/git/linux-2.6/fs/hostfs/hostfs_kern.c:328: error: dereferencing pointer to incomplete type We need to include mount.h to get vfsmount. Signed-off-by: Jiri Kosina <jkosina@suse.cz> Reported-by: Adrian Bunk <bunk@stusta.de> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-08mount options: fix hostfsMiklos Szeredi
Add the "host path" option to /proc/mounts for UML hostfs filesystems. The mount source (mnt_devname) should really be used for this, but not easy to change now in a backward compatible way. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-07iget: stop HOSTFS from using iget() and read_inode()David Howells
Stop the HOSTFS filesystem from using iget() and read_inode(). Provide hostfs_iget(), and call that instead of iget(). hostfs_iget() then uses iget_locked() directly and returns a proper error code instead of an inode in the event of an error. hostfs_fill_sb_common() returns any error incurred when getting the root inode instead of EINVAL. Note that the contents of hostfs_kern.c need to be examined: (*) hostfs_iget() should perhaps subsume init_inode() and hostfs_read_inode(). (*) It would appear that all hostfs inodes are the same inode because iget() was being called with inode number 0 - which forms the lookup key. [akpm@linux-foundation.org: coding-style fixes] Signed-off-by: David Howells <dhowells@redhat.com> Cc: Jeff Dike <jdike@addtoit.com> Acked-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05uml: fix hostfs tv_usec calculationsDominique Quatravaux
To convert from tv_nsec to tv_usec, one needs to divide by 1000, not multiply. Signed-off-by: Dominique Quatravaux <dominique@quatravaux.org> Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16uml: fix hostfs styleJeff Dike
Style fixes in hostfs. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16uml: remove unneeded if from hostfsJeff Dike
Get rid of an empty if statement which might look like a bug to a casual reader. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16UML: remove unnecessary hostfs_getattr()Miklos Szeredi
Currently hostfs_getattr() just defines the default behavior. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-16hostfs: convert to new aopsNick Piggin
This also gets rid of a lot of useless read_file stuff. And also optimises the full page write case by marking a !uptodate page uptodate. Signed-off-by: Nick Piggin <npiggin@suse.de> Cc: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-07-10sendfile: remove .sendfile from filesystems that use generic_file_sendfile()Jens Axboe
They can use generic_file_splice_read() instead. Since sys_sendfile() now prefers that, there should be no change in behaviour. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2007-05-08uml: hostfs style fixesJeff Dike
hostfs needed some style goodness. Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-08uml: make hostfs_setattr() support operations on unlinked open filesAlberto Bertogli
This patch allows hostfs_setattr() to work on unlinked open files by calling set_attr() (the userspace part) with the inode's fd. Without this, applications that depend on doing attribute changes to unlinked open files will fail. It works by using the fd versions instead of the path ones (for example fchmod() instead of chmod(), fchown() instead of chown()) when an fd is available. Signed-off-by: Alberto Bertogli <albertito@gmail.com> Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-29[PATCH] uml: hostfs variable renamingPaolo 'Blaisorblade' Giarrusso
* rename name to host_root_path * rename data to req_root. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Jeff Dike <jdike@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-29[PATCH] uml: fix compilation problemsJeff Dike
Fix a few miscellaneous compilation problems - an assignment with mismatched types in ldt.c a missing include in mconsole.h which needs a definition of uml_pt_regs I missed removing an include of user_util.h in hostfs Signed-off-by: Jeff Dike <jdike@linux.intel.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-08[PATCH] uml: hostfs: make hostfs= option work as a jail, as intended.Paolo 'Blaisorblade' Giarrusso
When a given host directory is specified to be mounted both in hostfs=path1 and with mount option -o path2, we should give access to path1/path2, but this does not happen. Fix that in the simpler way. Also, root_ino can be the empty string, since we use %s/%s as format. Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Acked-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-03-08[PATCH] uml: hostfs: fix double freePaolo 'Blaisorblade' Giarrusso
Fix double free in the error path - when name is assigned into root_inode we do not own it any more and we must not kfree() it - see patch for details. Thanks to William Stearns for the initial report. CC: William Stearns <wstearns@pobox.com> Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Acked-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12[PATCH] Mark struct super_operations constJosef 'Jeff' Sipek
This patch is inspired by Arjan's "Patch series to mark struct file_operations and struct inode_operations const". Compile tested with gcc & sparse. Signed-off-by: Josef 'Jeff' Sipek <jsipek@cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-02-12[PATCH] mark struct inode_operations const 2Arjan van de Ven
Many struct inode_operations in the kernel can be "const". Marking them const moves these to the .rodata section, which avoids false sharing with potential dirty data. In addition it'll catch accidental writes at compile time to these shared resources. Signed-off-by: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-01-30[PATCH] uml: fix mknodJohannes Stezenbach
Fix UML hostfs mknod(): userspace has differernt dev_t size and encoding than kernel, so extract major/minor and reencode using glibc makedev() macro. Signed-off-by: Johannes Stezenbach <js@linuxtv.org> Acked-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Jeff Dike <jdike@addtoit.com> Cc: <stable@kernel.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-12-08[PATCH] struct path: convert hostfsJosef Sipek
Signed-off-by: Josef Sipek <jsipek@fsl.cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01[PATCH] Streamline generic_file_* interfaces and filemap cleanupsBadari Pulavarty
This patch cleans up generic_file_*_read/write() interfaces. Christoph Hellwig gave me the idea for this clean ups. In a nutshell, all filesystems should set .aio_read/.aio_write methods and use do_sync_read/ do_sync_write() as their .read/.write methods. This allows us to cleanup all variants of generic_file_* routines. Final available interfaces: generic_file_aio_read() - read handler generic_file_aio_write() - write handler generic_file_aio_write_nolock() - no lock write handler __generic_file_aio_write_nolock() - internal worker routine Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-01[PATCH] Remove readv/writev methods and use aio_read/aio_write insteadBadari Pulavarty
This patch removes readv() and writev() methods and replaces them with aio_read()/aio_write() methods. Signed-off-by: Badari Pulavarty <pbadari@us.ibm.com> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-09-27[PATCH] inode-diet: Eliminate i_blksize from the inode structureTheodore Ts'o
This eliminates the i_blksize field from struct inode. Filesystems that want to provide a per-inode st_blksize can do so by providing their own getattr routine instead of using the generic_fillattr() function. Note that some filesystems were providing pretty much random (and incorrect) values for i_blksize. [bunk@stusta.de: cleanup] [akpm@osdl.org: generic_fillattr() fix] Signed-off-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-28[PATCH] mark address_space_operations constChristoph Hellwig
Same as with already do with the file operations: keep them in .rodata and prevents people from doing runtime patching. Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: Steven French <sfrench@us.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23[PATCH] VFS: Permit filesystem to perform statfs with a known root dentryDavid Howells
Give the statfs superblock operation a dentry pointer rather than a superblock pointer. This complements the get_sb() patch. That reduced the significance of sb->s_root, allowing NFS to place a fake root there. However, NFS does require a dentry to use as a target for the statfs operation. This permits the root in the vfsmount to be used instead. linux/mount.h has been added where necessary to make allyesconfig build successfully. Interest has also been expressed for use with the FUSE and XFS filesystems. Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Nathan Scott <nathans@sgi.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-23[PATCH] VFS: Permit filesystem to override root dentry on mountDavid Howells
Extend the get_sb() filesystem operation to take an extra argument that permits the VFS to pass in the target vfsmount that defines the mountpoint. The filesystem is then required to manually set the superblock and root dentry pointers. For most filesystems, this should be done with simple_set_mnt() which will set the superblock pointer and then set the root dentry to the superblock's s_root (as per the old default behaviour). The get_sb() op now returns an integer as there's now no need to return the superblock pointer. This patch permits a superblock to be implicitly shared amongst several mount points, such as can be done with NFS to avoid potential inode aliasing. In such a case, simple_set_mnt() would not be called, and instead the mnt_root and mnt_sb would be set directly. The patch also makes the following changes: (*) the get_sb_*() convenience functions in the core kernel now take a vfsmount pointer argument and return an integer, so most filesystems have to change very little. (*) If one of the convenience function is not used, then get_sb() should normally call simple_set_mnt() to instantiate the vfsmount. This will always return 0, and so can be tail-called from get_sb(). (*) generic_shutdown_super() now calls shrink_dcache_sb() to clean up the dcache upon superblock destruction rather than shrink_dcache_anon(). This is required because the superblock may now have multiple trees that aren't actually bound to s_root, but that still need to be cleaned up. The currently called functions assume that the whole tree is rooted at s_root, and that anonymous dentries are not the roots of trees which results in dentries being left unculled. However, with the way NFS superblock sharing are currently set to be implemented, these assumptions are violated: the root of the filesystem is simply a dummy dentry and inode (the real inode for '/' may well be inaccessible), and all the vfsmounts are rooted on anonymous[*] dentries with child trees. [*] Anonymous until discovered from another tree. (*) The documentation has been adjusted, including the additional bit of changing ext2_* into foo_* in the documentation. [akpm@osdl.org: convert ipath_fs, do other stuff] Signed-off-by: David Howells <dhowells@redhat.com> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Cc: Nathan Scott <nathans@sgi.com> Cc: Roland Dreier <rolandd@cisco.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28[PATCH] Make most file operations structs in fs/ constArjan van de Ven
This is a conversion to make the various file_operations structs in fs/ const. Basically a regexp job, with a few manual fixups The goal is both to increase correctness (harder to accidentally write to shared datastructures) and reducing the false sharing of cachelines with things that get dirty in .data (while .rodata is nicely read only and thus cache clean) Signed-off-by: Arjan van de Ven <arjan@infradead.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-27[PATCH] uml: fix hostfs stack corruptionJeff Dike
Noted by Oleg Drokin: We initialized an extra slot of struct kstatfs.spare, sometimes causing stack corruption. Signed-off-by: Jeff Dike <jdike@addtoit.com> Cc: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it> Cc: Oleg Drokin <green@clusterfs.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>