aboutsummaryrefslogtreecommitdiffstats
path: root/fs/notify/fanotify
Commit message (Collapse)AuthorAge
* Revert "fsnotify: store struct file not struct path"Linus Torvalds2010-08-12
| | | | | | | | | | | | | | | This reverts commit 3bcf3860a4ff9bbc522820b4b765e65e4deceb3e (and the accompanying commit c1e5c954020e "vfs/fsnotify: fsnotify_close can delay the final work in fput" that was a horribly ugly hack to make it work at all). The 'struct file' approach not only causes that disgusting hack, it somehow breaks pulseaudio, probably due to some other subtlety with f_count handling. Fix up various conflicts due to later fsnotify work. Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* fanotify: use both marks when possibleEric Paris2010-07-28
| | | | | | | | fanotify currently, when given a vfsmount_mark will look up (if it exists) the corresponding inode mark. This patch drops that lookup and uses the mark provided. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: pass both the vfsmount mark and inode markEric Paris2010-07-28
| | | | | | | | should_send_event() and handle_event() will both need to look up the inode event if they get a vfsmount event. Lets just pass both at the same time since we have them both after walking the lists in lockstep. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: remove group->maskEric Paris2010-07-28
| | | | | | | group->mask is now useless. It was originally a shortcut for fsnotify to save on performance. These checks are now redundant, so we remove them. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: cleanup should_send_eventEric Paris2010-07-28
| | | | | | | | The change to use srcu and walk the object list rather than the global fsnotify_group list means that should_send_event is no longer needed for a number of groups and can be simplified for others. Do that. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: use the mark in handler functionsEric Paris2010-07-28
| | | | | | | | fanotify now gets a mark in the should_send_event and handle_event functions. Rather than look up the mark themselves fanotify should just use the mark it was handed. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: send fsnotify_mark to groups in event handling functionsEric Paris2010-07-28
| | | | | | | | | With the change of fsnotify to use srcu walking the marks list instead of walking the global groups list we now know the mark in question. The code can send the mark to the group's handling functions and the groups won't have to find those marks themselves. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: store struct file not struct pathEric Paris2010-07-28
| | | | | | | | | Al explains that calling dentry_open() with a mnt/dentry pair is only garunteed to be safe if they are already used in an open struct file. To make sure this is the case don't store and use a struct path in fsnotify, always use a struct file. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: fsnotify_add_notify_event should return an eventEric Paris2010-07-28
| | | | | | | | | Rather than the horrific void ** argument and such just to pass the fanotify_merge event back to the caller of fsnotify_add_notify_event() have those things return an event if it was different than the event suggusted to be added. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: groups can specify their f_flags for new fdEric Paris2010-07-28
| | | | | | | | | Currently fanotify fds opened for thier listeners are done with f_flags equal to O_RDONLY | O_LARGEFILE. This patch instead takes f_flags from the fanotify_init syscall and uses those when opening files in the context of the listener. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: update gfp/slab.h includesTejun Heo2010-07-28
| | | | | | | | | | Implicit slab.h inclusion via percpu.h is about to go away. Make sure gfp.h or slab.h is included as necessary. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Stephen Rothwell <sfr@canb.auug.org.au> Cc: Eric Paris <eparis@redhat.com> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: drop the useless priority argumentEric Paris2010-07-28
| | | | | | The priority argument in fanotify is useless. Kill it. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: default Kconfig to nEric Paris2010-07-28
| | | | | | | fanotify has default to y in linux-next since it's inception but default to n in the final push to Linus. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: do not return 0 in a void functionEric Paris2010-07-28
| | | | | | | | remove_access_response() is supposed to have a void return, but was returning 0; Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: userspace interface for permission responsesEric Paris2010-07-28
| | | | | | | | fanotify groups need to respond to events which include permissions types. To do so groups will send a response using write() on the fanotify_fd they have open. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: permissions and blockingEric Paris2010-07-28
| | | | | | | | | This is the backend work needed for fanotify to support the new FS_OPEN_PERM and FS_ACCESS_PERM fsnotify events. This is done using the new fsnotify secondary queue. No userspace interface is provided actually respond to or request these events. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: use merge argument to determine actual event added to queueEric Paris2010-07-28
| | | | | | | | | fanotify needs to know the actual event added to queues so it can be correctly checked for return values from userspace. To do this we need to pass that information from the merger code back to the main even handling routine. Currently that information is unused, but it will be. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: intoduce a notification merge argumentEric Paris2010-07-28
| | | | | | | | | | | | | Each group can define their own notification (and secondary_q) merge function. Inotify does tail drop, fanotify does matching and drop which can actually allocate a completely new event. But for fanotify to properly deal with permissions events it needs to know the new event which was ultimately added to the notification queue. This patch just implements a void ** argument which is passed to the merge function. fanotify can use this field to pass the new event back to higher layers. Signed-off-by: Eric Paris <eparis@redhat.com> for fanotify to properly deal with permissions events
* fsnotify: add group prioritiesEric Paris2010-07-28
| | | | | | | | | | | | | | | | This introduces an ordering to fsnotify groups. With purely asynchronous notification based "things" implementing fsnotify (inotify, dnotify) ordering isn't particularly important. But if people want to use fsnotify for the basis of sycronous notification or blocking notification ordering becomes important. eg. A Hierarchical Storage Management listener would need to get its event before an AV scanner could get its event (since the HSM would need to bring the data in for the AV scanner to scan.) Typically asynchronous notification would want to run after the AV scanner made any relevant access decisions so as to not send notification about an event that was denied. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: clear all fanotify marksEric Paris2010-07-28
| | | | | | | | | fanotify listeners may want to clear all marks. They may want to do this to destroy all of their inode marks which have nothing but ignores. Realistically this is useful for av vendors who update policy and want to clear all of their cached allows. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: allow ignored_masks to survive modifyEric Paris2010-07-28
| | | | | | | | | Some users may want to truely ignore an inode even if it has been modified. Say you are wanting a mount which contains a log file and you really don't want any notification about that file. This patch allows the listener to do that. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: allow users to set an ignored_maskEric Paris2010-07-28
| | | | | | | | | | Change the sys_fanotify_mark() system call so users can set ignored_masks on inodes. Remember, if a user new sets a real mask, and only sets ignored masks, the ignore will never be pinned in memory. Thus ignored_masks can be lost under memory pressure and the user may again get events they previously thought were ignored. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: ignored_mask to ignore eventsEric Paris2010-07-28
| | | | | | | When fanotify receives an event it will check event->mask & ~ignored_mask. If no bits are left the event will not be sent. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: allow marks to not pin inodes in coreEric Paris2010-07-28
| | | | | | | | | | | | | | | | | inotify marks must pin inodes in core. dnotify doesn't technically need to since they are closed when the directory is closed. fanotify also need to pin inodes in core as it works today. But the next step is to introduce the concept of 'ignored masks' which is actually a mask of events for an inode of no interest. I claim that these should be liberally sent to the kernel and should not pin the inode in core. If the inode is brought back in the listener will get an event it may have thought excluded, but this is not a serious situation and one any listener should deal with. This patch lays the ground work for non-pinning inode marks by using lazy inode pinning. We do not pin a mark until it has a non-zero mask entry. If a listener new sets a mask we never pin the inode. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: remove outgoing function checks in fanotify.hAndreas Gruenbacher2010-07-28
| | | | | | | | | A number of validity checks on outgoing data are done in static inlines but are only used in one place. Instead just do them where they are used for readability. Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: remove fanotify.h declarationsAndreas Gruenbacher2010-07-28
| | | | | | | | | fanotify_mark_validate functions are all needlessly declared in headers as static inlines. Instead just do the checks where they are needed for code readability. Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: split fanotify_remove_markAndreas Gruenbacher2010-07-28
| | | | | | | | split fanotify_remove_mark into fanotify_remove_inode_mark and fanotify_remove_vfsmount_mark. Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: rename FAN_MARK_ON_VFSMOUNT to FAN_MARK_MOUNTAndreas Gruenbacher2010-07-28
| | | | | | | the term 'vfsmount' isn't sensicle to userspace. instead call is 'mount. Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: hooks the fanotify_mark syscall to the vfsmount codeEric Paris2010-07-28
| | | | | | | | Create a new fanotify_mark flag which indicates we should attach the mark to the vfsmount holding the object referenced by dfd and pathname rather than the inode itself. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: remove fanotify_add_markAndreas Gruenbacher2010-07-28
| | | | | | | fanotify_add_mark now does nothing useful anymore, drop it. Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: do not return pointer from fanotify_add_*_markAndreas Gruenbacher2010-07-28
| | | | | | | No need to return the mark from fanotify_add_*_mark to fanotify_add_mark Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: do not call fanotify_update_object_mask in fanotify_add_markAndreas Gruenbacher2010-07-28
| | | | | | | | | Recalculate masks in fanotify_add_mark, don't use fanotify_update_object_mask. This gets us one step closers to readable code. Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: do not call fanotify_update_object_mask in fanotify_remove_markAndreas Gruenbacher2010-07-28
| | | | | | | | | Recalculate masks in fanotify_remove_mark, don't use fanotify_update_object_mask. This gets us one step closers to readable code. Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: remove fanotify_update_markAndreas Gruenbacher2010-07-28
| | | | | | | fanotify_update_mark() doesn't do much useful; remove it. Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: infrastructure to add an remove marks on vfsmountsEric Paris2010-07-28
| | | | | | | infrastructure work to add and remove marks on vfsmounts. This should get every set up except wiring the functions to the syscalls. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: should_send_event needs to handle vfsmountsEric Paris2010-07-28
| | | | | | | | currently should_send_event in fanotify only cares about marks on inodes. This patch extends that interface to indicate that it cares about events that happened on vfsmounts. Signed-off-by: Eric Paris <eparis@redhat.com>
* fsnotify: split generic and inode specific mark codeEric Paris2010-07-28
| | | | | | | | currently all marking is done by functions in inode-mark.c. Some of this is pretty generic and should be instead done in a generic function and we should only put the inode specific code in inode-mark.c Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: Add pids to eventsAndreas Gruenbacher2010-07-28
| | | | | | | | Pass the process identifiers of the triggering processes to fanotify listeners: this information is useful for event filtering and logging. Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: create_fd cleanupAndreas Gruenbacher2010-07-28
| | | | | | | | Code cleanup which does the fd creation work seperately from the userspace metadata creation. It fits better with the other code. Signed-off-by: Andreas Gruenbacher <agruen@suse.de> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: CONFIG_HAVE_SYSCALL_WRAPPERS for sys_fanotify_markHeiko Carstens2010-07-28
| | | | | | | | | | | | | | | | | Please note that you need the patch below in addition, otherwise the syscall wrapper stuff won't work on those 32 bit architectures which enable the wrappers. When enabled the syscall wrapper defines always take long parameters and then cast them to whatever is needed. This approach doesn't work for the 32 bit case where the original syscall takes a long long parameter, since we would lose the upper 32 bits. So syscalls with 64 bit arguments are special cases wrt to syscall wrappers and enp up in the ugliness below (see also sys_fallocate). In addition these special cased syscall wrappers have the drawback that ftrace syscall tracing doesn't work on them, since they don't get defined by using the usual macros. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: select ANON_INODES.Paul Mundt2010-07-28
| | | | | | | | | | | | | | | fanotify references anon_inode_getfd(), which is only available with ANON_INODES enabled. Presently this bails out with the following: LD vmlinux fs/built-in.o: In function `sys_fanotify_init': (.text+0x26d1c): undefined reference to `anon_inode_getfd' make: *** [vmlinux] Error 1 which is trivially corrected by adding an ANON_INODES select. Signed-off-by: Paul Mundt <lethal@linux-sh.org> Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: send events using readEric Paris2010-07-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Send events to userspace by reading the file descriptor from fanotify_init(). One will get blocks of data which look like: struct fanotify_event_metadata { __u32 event_len; __u32 vers; __s32 fd; __u64 mask; __s64 pid; __u64 cookie; } __attribute__ ((packed)); Simple code to retrieve and deal with events is below while ((len = read(fan_fd, buf, sizeof(buf))) > 0) { struct fanotify_event_metadata *metadata; metadata = (void *)buf; while(FAN_EVENT_OK(metadata, len)) { [PROCESS HERE!!] if (metadata->fd >= 0 && close(metadata->fd) != 0) goto fail; metadata = FAN_EVENT_NEXT(metadata, len); } } Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: fanotify_mark syscall implementationEric Paris2010-07-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | NAME fanotify_mark - add, remove, or modify an fanotify mark on a filesystem object SYNOPSIS int fanotify_mark(int fanotify_fd, unsigned int flags, u64 mask, int dfd, const char *pathname) DESCRIPTION fanotify_mark() is used to add remove or modify a mark on a filesystem object. Marks are used to indicate that the fanotify group is interested in events which occur on that object. At this point in time marks may only be added to files and directories. fanotify_fd must be a file descriptor returned by fanotify_init() The flags field must contain exactly one of the following: FAN_MARK_ADD - or the bits in mask and ignored mask into the mark FAN_MARK_REMOVE - bitwise remove the bits in mask and ignored mark from the mark The following values can be OR'd into the flags field: FAN_MARK_DONT_FOLLOW - same meaning as O_NOFOLLOW as described in open(2) FAN_MARK_ONLYDIR - same meaning as O_DIRECTORY as described in open(2) dfd may be any of the following: AT_FDCWD: the object will be lookup up based on pathname similar to open(2) file descriptor of a directory: if pathname is not NULL the object to modify will be lookup up similar to openat(2) file descriptor of the final object: if pathname is NULL the object to modify will be the object referenced by dfd The mask is the bitwise OR of the set of events of interest such as: FAN_ACCESS - object was accessed (read) FAN_MODIFY - object was modified (write) FAN_CLOSE_WRITE - object was writable and was closed FAN_CLOSE_NOWRITE - object was read only and was closed FAN_OPEN - object was opened FAN_EVENT_ON_CHILD - interested in objected that happen to children. Only relavent when the object is a directory FAN_Q_OVERFLOW - event queue overflowed (not implemented) RETURN VALUE On success, this system call returns 0. On error, -1 is returned, and errno is set to indicate the error. ERRORS EINVAL An invalid value was specified in flags. EINVAL An invalid value was specified in mask. EINVAL An invalid value was specified in ignored_mask. EINVAL fanotify_fd is not a file descriptor as returned by fanotify_init() EBADF fanotify_fd is not a valid file descriptor EBADF dfd is not a valid file descriptor and path is NULL. ENOTDIR dfd is not a directory and path is not NULL EACCESS no search permissions on some part of the path ENENT file not found ENOMEM Insufficient kernel memory is available. CONFORMING TO These system calls are Linux-specific. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: sys_fanotify_mark declartionEric Paris2010-07-28
| | | | | | | | | This patch simply declares the new sys_fanotify_mark syscall int fanotify_mark(int fanotify_fd, unsigned int flags, u64_mask, int dfd const char *pathname) Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: fanotify_init syscall implementationEric Paris2010-07-28
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | NAME fanotify_init - initialize an fanotify group SYNOPSIS int fanotify_init(unsigned int flags, unsigned int event_f_flags, int priority); DESCRIPTION fanotify_init() initializes a new fanotify instance and returns a file descriptor associated with the new fanotify event queue. The following values can be OR'd into the flags field: FAN_NONBLOCK Set the O_NONBLOCK file status flag on the new open file description. Using this flag saves extra calls to fcntl(2) to achieve the same result. FAN_CLOEXEC Set the close-on-exec (FD_CLOEXEC) flag on the new file descriptor. See the description of the O_CLOEXEC flag in open(2) for reasons why this may be useful. The event_f_flags argument is unused and must be set to 0 The priority argument is unused and must be set to 0 RETURN VALUE On success, this system call return a new file descriptor. On error, -1 is returned, and errno is set to indicate the error. ERRORS EINVAL An invalid value was specified in flags. EINVAL A non-zero valid was passed in event_f_flags or in priority ENFILE The system limit on the total number of file descriptors has been reached. ENOMEM Insufficient kernel memory is available. CONFORMING TO These system calls are Linux-specific. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: fanotify_init syscall declarationEric Paris2010-07-28
| | | | | | | | | | | | This patch defines a new syscall fanotify_init() of the form: int sys_fanotify_init(unsigned int flags, unsigned int event_f_flags, unsigned int priority) This syscall is used to create and fanotify group. This is very similar to the inotify_init() syscall. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: do not clone on merge unless neededEric Paris2010-07-28
| | | | | | | | | | | | | | Currently if 2 events are going to be merged on the notication queue with different masks the second event will be cloned and will replace the first event. However if this notification queue is the only place referencing the event in question there is no reason not to just update the event in place. We can tell this if the event->refcnt == 1. Since we hold a reference for each queue this event is on we know that when refcnt == 1 this is the only queue. The other concern is that it might be about to be added to a new queue, but this can't be the case since fsnotify holds a reference on the event until it is finished adding it to queues. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: merge notification events with different masksEric Paris2010-07-28
| | | | | | | | | Instead of just merging fanotify events if they are exactly the same, merge notification events with different masks. To do this we have to clone the old event, update the mask in the new event with the new merged mask, and put the new event in place of the old event. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify:drop notification if they exist in the outgoing queueEric Paris2010-07-28
| | | | | | | | | | fanotify listeners get an open file descriptor to the object in question so the ordering of operations is not as important as in other notification systems. inotify will drop events if the last event in the event FIFO is the same as the current event. This patch will drop fanotify events if they are the same as another event anywhere in the event FIFO. Signed-off-by: Eric Paris <eparis@redhat.com>
* fanotify: fscking all notification systemEric Paris2010-07-28
fanotify is a novel file notification system which bases notification on giving userspace both an event type (open, close, read, write) and an open file descriptor to the object in question. This should address a number of races and problems with other notification systems like inotify and dnotify and should allow the future implementation of blocking or access controlled notification. These are useful for on access scanners or hierachical storage management schemes. This patch just implements the basics of the fsnotify functions. Signed-off-by: Eric Paris <eparis@redhat.com>