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path: root/fs/xattr.c
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2009-12-16sanitize xattr handler prototypesChristoph Hellwig
Add a flags argument to struct xattr_handler and pass it to all xattr handler methods. This allows using the same methods for multiple handlers, e.g. for the ACL methods which perform exactly the same action for the access and default ACLs, just using a different underlying attribute. With a little more groundwork it'll also allow sharing the methods for the regular user/trusted/secure handlers in extN, ocfs2 and jffs2 like it's already done for xfs in this patch. Also change the inode argument to the handlers to a dentry to allow using the handlers mechnism for filesystems that require it later, e.g. cifs. [with GFS2 bits updated by Steven Whitehouse <swhiteho@redhat.com>] Signed-off-by: Christoph Hellwig <hch@lst.de> Reviewed-by: James Morris <jmorris@namei.org> Acked-by: Joel Becker <joel.becker@oracle.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-09-10VFS: Factor out part of vfs_setxattr so it can be called from the SELinux ↵David P. Quigley
hook for inode_setsecctx. This factors out the part of the vfs_setxattr function that performs the setting of the xattr and its notification. This is needed so the SELinux implementation of inode_setsecctx can handle the setting of the xattr while maintaining the proper separation of layers. Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
2009-06-11fs: introduce mnt_clone_writenpiggin@suse.de
This patch speeds up lmbench lat_mmap test by about another 2% after the first patch. Before: avg = 462.286 std = 5.46106 After: avg = 453.12 std = 9.58257 (50 runs of each, stddev gives a reasonable confidence) It does this by introducing mnt_clone_write, which avoids some heavyweight operations of mnt_want_write if called on a vfsmount which we know already has a write count; and mnt_want_write_file, which can call mnt_clone_write if the file is open for write. After these two patches, mnt_want_write and mnt_drop_write go from 7% on the profile down to 1.3% (including mnt_clone_write). [AV: mnt_want_write_file() should take file alone and derive mnt from it; not only all callers have that form, but that's the only mnt about which we know that it's already held for write if file is opened for write] Cc: Dave Hansen <haveblue@us.ibm.com> Signed-off-by: Nick Piggin <npiggin@suse.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-04-20xattr: use memdup_user()Li Zefan
Remove open-coded memdup_user() Signed-off-by: Li Zefan <lizf@cn.fujitsu.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-01-14[CVE-2009-0029] System call wrappers part 13Heiko Carstens
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2009-01-14[CVE-2009-0029] System call wrappers part 12Heiko Carstens
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2009-01-14[CVE-2009-0029] Convert all system calls to return a longHeiko Carstens
Convert all system calls to return a long. This should be a NOP since all converted types should have the same size anyway. With the exception of sys_exit_group which returned void. But that doesn't matter since the system call doesn't return. Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
2009-01-05inode->i_op is never NULLAl Viro
We used to have rather schizophrenic set of checks for NULL ->i_op even though it had been eliminated years ago. You'd need to go out of your way to set it to NULL explicitly _and_ a bunch of code would die on such inodes anyway. After killing two remaining places that still did that bogosity, all that crap can go away. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26[PATCH] sanitize __user_walk_fd() et.al.Al Viro
* do not pass nameidata; struct path is all the callers want. * switch to new helpers: user_path_at(dfd, pathname, flags, &path) user_path(pathname, &path) user_lpath(pathname, &path) user_path_dir(pathname, &path) (fail if not a directory) The last 3 are trivial macro wrappers for the first one. * remove nameidata in callers. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-07-26[PATCH] kill nameidata passing to permission(), rename to inode_permission()Al Viro
Incidentally, the name that gives hundreds of false positives on grep is not a good idea... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-29xattr: add missing consts to function argumentsDavid Howells
Add missing consts to xattr function arguments. Signed-off-by: David Howells <dhowells@redhat.com> Cc: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-04-23[PATCH] remove unused label in xattr.c (noise from ro-bind)Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-04-19[PATCH] r/o bind mounts: elevate write count for xattr_permission() callersDave Hansen
This basically audits the callers of xattr_permission(), which calls permission() and can perform writes to the filesystem. [AV: add missing parts - removexattr() and nfsd posix acls, plug for a leak spotted by Miklos] Acked-by: Al Viro <viro@ZenIV.linux.org.uk> Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Dave Hansen <haveblue@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2008-02-14Introduce path_put()Jan Blunck
* Add path_put() functions for releasing a reference to the dentry and vfsmount of a struct path in the right order * Switch from path_release(nd) to path_put(&nd->path) * Rename dput_path() to path_put_conditional() [akpm@linux-foundation.org: fix cifs] Signed-off-by: Jan Blunck <jblunck@suse.de> Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Acked-by: Christoph Hellwig <hch@lst.de> Cc: <linux-fsdevel@vger.kernel.org> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Steven French <sfrench@us.ibm.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-14Embed a struct path into struct nameidata instead of nd->{dentry,mnt}Jan Blunck
This is the central patch of a cleanup series. In most cases there is no good reason why someone would want to use a dentry for itself. This series reflects that fact and embeds a struct path into nameidata. Together with the other patches of this series - it enforced the correct order of getting/releasing the reference count on <dentry,vfsmount> pairs - it prepares the VFS for stacking support since it is essential to have a struct path in every place where the stack can be traversed - it reduces the overall code size: without patch series: text data bss dec hex filename 5321639 858418 715768 6895825 6938d1 vmlinux with patch series: text data bss dec hex filename 5320026 858418 715768 6894212 693284 vmlinux This patch: Switch from nd->{dentry,mnt} to nd->path.{dentry,mnt} everywhere. [akpm@linux-foundation.org: coding-style fixes] [akpm@linux-foundation.org: fix cifs] [akpm@linux-foundation.org: fix smack] Signed-off-by: Jan Blunck <jblunck@suse.de> Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Acked-by: Christoph Hellwig <hch@lst.de> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Casey Schaufler <casey@schaufler-ca.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05VFS: Reorder vfs_getxattr to avoid unnecessary calls to the LSMDavid P. Quigley
Originally vfs_getxattr would pull the security xattr variable using the inode getxattr handle and then proceed to clobber it with a subsequent call to the LSM. This patch reorders the two operations such that when the xattr requested is in the security namespace it first attempts to grab the value from the LSM directly. If it fails to obtain the value because there is no module present or the module does not support the operation it will fall back to using the inode getxattr operation. In the event that both are inaccessible it returns EOPNOTSUPP. Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Chris Wright <chrisw@sous-sol.org> Acked-by: James Morris <jmorris@namei.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: Casey Schaufler <casey@schaufler-ca.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-02-05VFS/Security: Rework inode_getsecurity and callers to return resulting bufferDavid P. Quigley
This patch modifies the interface to inode_getsecurity to have the function return a buffer containing the security blob and its length via parameters instead of relying on the calling function to give it an appropriately sized buffer. Security blobs obtained with this function should be freed using the release_secctx LSM hook. This alleviates the problem of the caller having to guess a length and preallocate a buffer for this function allowing it to be used elsewhere for Labeled NFS. The patch also removed the unused err parameter. The conversion is similar to the one performed by Al Viro for the security_getprocattr hook. Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov> Cc: Stephen Smalley <sds@tycho.nsa.gov> Cc: Chris Wright <chrisw@sous-sol.org> Acked-by: James Morris <jmorris@namei.org> Acked-by: Serge Hallyn <serue@us.ibm.com> Cc: Casey Schaufler <casey@schaufler-ca.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-10-21[PATCH] pass dentry to audit_inode()/audit_inode_child()Al Viro
makes caller simpler *and* allows to scan ancestors Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2007-07-17Introduce is_owner_or_cap() to wrap CAP_FOWNER use with fsuid checkSatyam Sharma
Introduce is_owner_or_cap() macro in fs.h, and convert over relevant users to it. This is done because we want to avoid bugs in the future where we check for only effective fsuid of the current task against a file's owning uid, without simultaneously checking for CAP_FOWNER as well, thus violating its semantics. [ XFS uses special macros and structures, and in general looked ... untouchable, so we leave it alone -- but it has been looked over. ] The (current->fsuid != inode->i_uid) check in generic_permission() and exec_permission_lite() is left alone, because those operations are covered by CAP_DAC_OVERRIDE and CAP_DAC_READ_SEARCH. Similarly operations falling under the purview of CAP_CHOWN and CAP_LEASE are also left alone. Signed-off-by: Satyam Sharma <ssatyam@cse.iitk.ac.in> Cc: Al Viro <viro@ftp.linux.org.uk> Acked-by: Serge E. Hallyn <serge@hallyn.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2007-05-11[PATCH] audit inode for all xattr syscallsAmy Griffis
Collect inode info for the remaining xattr syscalls that operate on a file descriptor. These don't call a path_lookup variant, so they aren't covered by the general audit hook. Signed-off-by: Amy Griffis <amy.griffis@hp.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2007-05-08header cleaning: don't include smp_lock.h when not usedRandy Dunlap
Remove includes of <linux/smp_lock.h> where it is not used/needed. Suggested by Al Viro. Builds cleanly on x86_64, i386, alpha, ia64, powerpc, sparc, sparc64, and arm (all 59 defconfigs). Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2006-12-08[PATCH] VFS: change struct file to use struct pathJosef "Jeff" Sipek
This patch changes struct file to use struct path instead of having independent pointers to struct dentry and struct vfsmount, and converts all users of f_{dentry,vfsmnt} in fs/ to use f_path.{dentry,mnt}. Additionally, it adds two #define's to make the transition easier for users of the f_dentry and f_vfsmnt. Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-11-03[PATCH] Fix user.* xattr permission check for sticky dirsAndreas Gruenbacher
The user.* extended attributes are only allowed on regular files and directories. Sticky directories further restrict write access to the owner and privileged users. (See the attr(5) man page for an explanation.) The original check in ext2/ext3 when user.* xattrs were merged was more restrictive than intended, and when the xattr permission checks were moved into the VFS, read access to user.* attributes on sticky directores ended up being denied in addition. Originally-from: Gerard Neil <xyzzy@devferret.org> Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Cc: Dave Kleikamp <shaggy@austin.ibm.com> Cc: Jan Engelhardt <jengelh@linux01.gwdg.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-10-09[PATCH] Introduce vfs_listxattrBill Nottingham
This patch moves code out of fs/xattr.c:listxattr into a new function - vfs_listxattr. The code for vfs_listxattr was originally submitted by Bill Nottingham <notting@redhat.com> to Unionfs. Sorry about that. The reason for this submission is to make the listxattr code in fs/xattr.c a little cleaner (as well as to clean up some code in Unionfs.) Currently, Unionfs has vfs_listxattr defined in its code. I think that's very ugly, and I'd like to see it (re)moved. The logical place to put it, is along side of all the other vfs_*xattr functions. Overall, I think this patch is benefitial for both kernel.org kernel and Unionfs. Signed-off-by: Josef "Jeff" Sipek <jsipek@cs.sunysb.edu> Acked-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-06-20[PATCH] log more info for directory entry change eventsAmy Griffis
When an audit event involves changes to a directory entry, include a PATH record for the directory itself. A few other notable changes: - fixed audit_inode_child() hooks in fsnotify_move() - removed unused flags arg from audit_inode() - added audit log routines for logging a portion of a string Here's some sample output. before patch: type=SYSCALL msg=audit(1149821605.320:26): arch=40000003 syscall=39 success=yes exit=0 a0=bf8d3c7c a1=1ff a2=804e1b8 a3=bf8d3c7c items=1 ppid=739 pid=800 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=ttyS0 comm="mkdir" exe="/bin/mkdir" subj=root:system_r:unconfined_t:s0-s0:c0.c255 type=CWD msg=audit(1149821605.320:26): cwd="/root" type=PATH msg=audit(1149821605.320:26): item=0 name="foo" parent=164068 inode=164010 dev=03:00 mode=040755 ouid=0 ogid=0 rdev=00:00 obj=root:object_r:user_home_t:s0 after patch: type=SYSCALL msg=audit(1149822032.332:24): arch=40000003 syscall=39 success=yes exit=0 a0=bfdd9c7c a1=1ff a2=804e1b8 a3=bfdd9c7c items=2 ppid=714 pid=777 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=ttyS0 comm="mkdir" exe="/bin/mkdir" subj=root:system_r:unconfined_t:s0-s0:c0.c255 type=CWD msg=audit(1149822032.332:24): cwd="/root" type=PATH msg=audit(1149822032.332:24): item=0 name="/root" inode=164068 dev=03:00 mode=040750 ouid=0 ogid=0 rdev=00:00 obj=root:object_r:user_home_dir_t:s0 type=PATH msg=audit(1149822032.332:24): item=1 name="foo" inode=164010 dev=03:00 mode=040755 ouid=0 ogid=0 rdev=00:00 obj=root:object_r:user_home_t:s0 Signed-off-by: Amy Griffis <amy.griffis@hp.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-03-20[PATCH] Collect more inode information during syscall processing.Amy Griffis
This patch augments the collection of inode info during syscall processing. It represents part of the functionality that was provided by the auditfs patch included in RHEL4. Specifically, it: - Collects information for target inodes created or removed during syscalls. Previous code only collects information for the target inode's parent. - Adds the audit_inode() hook to syscalls that operate on a file descriptor (e.g. fchown), enabling audit to do inode filtering for these calls. - Modifies filtering code to check audit context for either an inode # or a parent inode # matching a given rule. - Modifies logging to provide inode # for both parent and child. - Protect debug info from NULL audit_names.name. [AV: folded a later typo fix from the same author] Signed-off-by: Amy Griffis <amy.griffis@hp.com> Signed-off-by: David Woodhouse <dwmw2@infradead.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2006-01-10[PATCH] move xattr permission checks into the VFSakpm@osdl.org
) From: Christoph Hellwig <hch@lst.de> The xattr code has rather complex permission checks because the rules are very different for different attribute namespaces. This patch moves as much as we can into the generic code. Currently all the major disk based filesystems duplicate these checks, while many minor filesystems or network filesystems lack some or all of them. To do this we need defines for the extended attribute names in common code, I moved them up from JFS which had the nicest defintions. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Dave Kleikamp <shaggy@austin.ibm.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10[PATCH] add vfs_* helpers for xattr operationsChristoph Hellwig
Add vfs_getxattr, vfs_setxattr and vfs_removexattr helpers for common checks around invocation of the xattr methods. NFSD already was missing some of the checks and there will be more soon. Signed-off-by: Christoph Hellwig <hch@lst.de> Cc: James Morris <jmorris@namei.org> (James, I haven't touched selinux yet because it's doing various odd things and I'm not sure how it would interact with the security attribute fallbacks you added. Could you investigate whether it could use vfs_getxattr or if not add a __vfs_getxattr helper to share the bits it is fine with?) For NFSv4: instead of just converting it add an nfsd_getxattr helper for the code shared by NFSv2/3 and NFSv4 ACLs. In fact that code isn't even NFS-specific, but I'll wait for more users to pop up first before moving it to common code. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Dave Kleikamp <shaggy@austin.ibm.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Neil Brown <neilb@suse.de> Cc: Trond Myklebust <trond.myklebust@fys.uio.no> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-09[PATCH] mutex subsystem, semaphore to mutex: VFS, ->i_semJes Sorensen
This patch converts the inode semaphore to a mutex. I have tested it on XFS and compiled as much as one can consider on an ia64. Anyway your luck with it might be different. Modified-by: Ingo Molnar <mingo@elte.hu> (finished the conversion) Signed-off-by: Jes Sorensen <jes@sgi.com> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2005-12-12[PATCH] Fix listxattr() for generic security attributesDaniel Drake
Commit f549d6c18c0e8e6cf1bf0e7a47acc1daf7e2cec1 introduced a generic fallback for security xattrs, but appears to include a subtle bug. Gentoo users with kernels with selinux compiled in, and coreutils compiled with acl support, noticed that they could not copy files on tmpfs using 'cp'. cp (compiled with acl support) copies the file, lists the extended attributes on the old file, copies them all to the new file, and then exits. However the listxattr() calls were failing with this odd behaviour: llistxattr("a.out", (nil), 0) = 17 llistxattr("a.out", 0x7fffff8c6cb0, 17) = -1 ERANGE (Numerical result out of range) I believe this is a simple problem in the logic used to check the buffer sizes; if the user sends a buffer the exact size of the data, then its ok :) This change solves the problem. More info can be found at http://bugs.gentoo.org/113138 Signed-off-by: Daniel Drake <dsd@gentoo.org> Acked-by: James Morris <jmorris@namei.org> Acked-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-11-07[PATCH] kfree cleanup: fsJesper Juhl
This is the fs/ part of the big kfree cleanup patch. Remove pointless checks for NULL prior to calling kfree() in fs/. Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-10-30[PATCH] SELinux: canonicalize getxattr()James Morris
This patch allows SELinux to canonicalize the value returned from getxattr() via the security_inode_getsecurity() hook, which is called after the fs level getxattr() function. The purpose of this is to allow the in-core security context for an inode to override the on-disk value. This could happen in cases such as upgrading a system to a different labeling form (e.g. standard SELinux to MLS) without needing to do a full relabel of the filesystem. In such cases, we want getxattr() to return the canonical security context that the kernel is using rather than what is stored on disk. The implementation hooks into the inode_getsecurity(), adding another parameter to indicate the result of the preceding fs-level getxattr() call, so that SELinux knows whether to compare a value obtained from disk with the kernel value. We also now allow getxattr() to work for mountpoint labeled filesystems (i.e. mount with option context=foo_t), as we are able to return the kernel value to the user. Signed-off-by: James Morris <jmorris@namei.org> Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-07[PATCH] fsnotify: hook on removexattr, tooRobert Love
Add fsnotify_xattr() hook to removexattr(). Signed-off-by: Robert Love <rml@novell.com> Signed-off-by: John McCtuchan <ttb@tentacle.dhs.org> Cc: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-09-05[PATCH] Generic VFS fallback for security xattrsStephen Smalley
This patch modifies the VFS setxattr, getxattr, and listxattr code to fall back to the security module for security xattrs if the filesystem does not support xattrs natively. This allows security modules to export the incore inode security label information to userspace even if the filesystem does not provide xattr storage, and eliminates the need to individually patch various pseudo filesystem types to provide such access. The patch removes the existing xattr code from devpts and tmpfs as it is then no longer needed. The patch restructures the code flow slightly to reduce duplication between the normal path and the fallback path, but this should only have one user-visible side effect - a program may get -EACCES rather than -EOPNOTSUPP if policy denied access but the filesystem didn't support the operation anyway. Note that the post_setxattr hook call is not needed in the fallback case, as the inode_setsecurity hook call handles the incore inode security state update directly. In contrast, we do call fsnotify in both cases. Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov> Acked-by: James Morris <jmorris@namei.org> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-07-12[PATCH] inotifyRobert Love
inotify is intended to correct the deficiencies of dnotify, particularly its inability to scale and its terrible user interface: * dnotify requires the opening of one fd per each directory that you intend to watch. This quickly results in too many open files and pins removable media, preventing unmount. * dnotify is directory-based. You only learn about changes to directories. Sure, a change to a file in a directory affects the directory, but you are then forced to keep a cache of stat structures. * dnotify's interface to user-space is awful. Signals? inotify provides a more usable, simple, powerful solution to file change notification: * inotify's interface is a system call that returns a fd, not SIGIO. You get a single fd, which is select()-able. * inotify has an event that says "the filesystem that the item you were watching is on was unmounted." * inotify can watch directories or files. Inotify is currently used by Beagle (a desktop search infrastructure), Gamin (a FAM replacement), and other projects. See Documentation/filesystems/inotify.txt. Signed-off-by: Robert Love <rml@novell.com> Cc: John McCutchan <ttb@tentacle.dhs.org> Cc: Christoph Hellwig <hch@lst.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2005-04-16Linux-2.6.12-rc2v2.6.12-rc2Linus Torvalds
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!