- 28 Jul, 2010 40 commits
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Eric Paris authored
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>
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Eric Paris authored
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: -
Andreas Gruenbacher authored
Per-mount watches allow groups to listen to fsnotify events on an entire mount. This patch simply adds and initializes the fields needed in the vfsmount struct to make this happen. Signed-off-by:
Andreas Gruenbacher <agruen@suse.de> Signed-off-by:
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Eric Paris authored
Much like inode-mark.c has all of the code dealing with marks on inodes this patch adds a vfsmount-mark.c which has similar code but is intended for marks on vfsmounts. Signed-off-by: -
Andreas Gruenbacher authored
This patch adds the list and mask fields needed to support vfsmount marks. These are the same fields fsnotify needs on an inode. They are not used, just declared and we note where the cleanup hook should be (the function is not yet defined) Signed-off-by:
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Eric Paris authored
Currently fsnotify_init_mark sets some fields to 0/NULL. Some users already used some sorts of zalloc, some didn't. This patch uses memset to explicitly zero everything in the fsnotify_mark when it is initialized so we don't have to be careful if fields are later added to marks. Signed-off-by: -
Eric Paris authored
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: -
Andreas Gruenbacher authored
Pass the process identifiers of the triggering processes to fanotify listeners: this information is useful for event filtering and logging. Signed-off-by:
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Andreas Gruenbacher authored
Code cleanup which does the fd creation work seperately from the userspace metadata creation. It fits better with the other code. Signed-off-by:
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Heiko Carstens authored
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: -
Paul Mundt authored
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:
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Eric Paris authored
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 authored
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 authored
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 authored
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 authored
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 authored
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 authored
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 authored
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 authored
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: -
Signed-off-by: Wu Fengguang authored
sparc used the same value as FMODE_NONOTIFY so change FMODE_NONOTIFY to be something unique. Signed-off-by:
Wu Fengguang <fengguang.wu@intel.com> Signed-off-by:
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Eric Paris authored
This is a new f_mode which can only be set by the kernel. It indicates that the fd was opened by fanotify and should not cause future fanotify events. This is needed to prevent fanotify livelock. An example of obvious livelock is from fanotify close events. Process A closes file1 This creates a close event for file1. fanotify opens file1 for Listener X Listener X deals with the event and closes its fd for file1. This creates a close event for file1. fanotify opens file1 for Listener X Listener X deals with the event and closes its fd for file1. This creates a close event for file1. fanotify opens file1 for Listener X Listener X deals with the event and closes its fd for file1. notice a pattern? The fix is to add the FMODE_NONOTIFY bit to the open filp done by the kernel for fanotify. Thus when that file is used it will not generate future events. This patch simply defines the bit. Signed-off-by: -
Andreas Gruenbacher authored
All callers to fsnotify_find_mark_entry() except one take and release inode->i_lock around the call. Take the lock inside fsnotify_find_mark_entry() instead. Signed-off-by:
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Eric Paris authored
nomenclature change. Used to call things 'entries' but now we just call them 'marks.' Do those changes for dnotify. Signed-off-by: -
Eric Paris authored
rename anything in inotify that deals with mark_entry to just be mark. It makes a lot more sense. Signed-off-by: -
Eric Paris authored
previously I used mark_entry when talking about marks on inodes. The _entry is pretty useless. Just use "mark" instead. Signed-off-by: -
Eric Paris authored
the _entry portion of fsnotify functions is useless. Drop it. Signed-off-by: -
Eric Paris authored
The name is long and it serves no real purpose. So rename fsnotify_mark_entry to just fsnotify_mark. Signed-off-by: -
Andreas Gruenbacher authored
Some fsnotify operations send a struct file. This is more information than we technically need. We instead send a struct path in all cases instead of sometimes a path and sometimes a file. Signed-off-by:
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Eric Paris authored
To differentiate between inode and vfsmount (or other future) types of marks we add a flags field and set the inode bit on inode marks (the only currently supported type of mark) Signed-off-by: -
Eric Paris authored
vfsmount marks need mostly the same data as inode specific fields, but for consistency and understandability we put that data in a vfsmount specific struct inside a union with inode specific data. Signed-off-by: -
Eric Paris authored
The addition of marks on vfs mounts will be simplified if the inode specific parts of a mark and the vfsmnt specific parts of a mark are actually in a union so naming can be easy. This patch just implements the inode struct and the union. Signed-off-by: -
Eric Paris authored
To ensure that a group will not duplicate events when it receives it based on the vfsmount and the inode should_send_event test we should distinguish those two cases. We pass a vfsmount to this function so groups can make their own determinations. Signed-off-by: -
Eric Paris authored
currently all of the notification systems implemented select which inodes they care about and receive messages only about those inodes (or the children of those inodes.) This patch begins to flesh out fsnotify support for the concept of listeners that want to hear notification for an inode accessed below a given monut point. This patch implements a second list of fsnotify groups to hold these types of groups and a second global mask to hold the events of interest for this type of group. The reason we want a second group list and mask is because the inode based notification should_send_event support which makes each group look for a mark on the given inode. With one nfsmount listener that means that every group would have to take the inode->i_lock, look for their mark, not find one, and return for every operation. By seperating vfsmount from inode listeners only when there is a inode listener will the inode groups have to look for their mark and take the inode lock. vfsmount listeners will have to grab the lock and look for a mark but there should be fewer of them, and one vfsmount listener won't cause the i_lock to be grabbed and released for every fsnotify group on every io operation. Signed-off-by: -
Eric Paris authored
Currently all fsnotify groups are added immediately to the fsnotify_inode_groups list upon creation. This means, even groups with no watches (common for audit) will be on the global tracking list and will get checked for every event. This patch adds groups to the global list on when the first inode mark is added to the group. Signed-of-by: -
Eric Paris authored
Currently the comments say that group->num_marks is held because the group is on the fsnotify_group list. This isn't strictly the case, we really just hold the num_marks for the life of the group (any time group->refcnt is != 0) This patch moves the initialization stuff and makes it clear when it is really being held. Signed-off-by: -
Eric Paris authored
Simple renaming patch. fsnotify is about to support mount point listeners so I am renaming fsnotify_groups and fsnotify_mask to indicate these are lists used only for groups which have watches on inodes. Signed-off-by: -
Eric Paris authored
Nothing uses the mask argument to fsnotify_alloc_group. This patch drops that argument. Signed-off-by: -
Eric Paris authored
Currently the audit watch group always sets a mask equal to all events it might care about. We instead should only set the group mask if we are actually watching inodes. This should be a perf win when audit watches are compiled in. Signed-off-by: -
Eric Paris authored
fsnotify_obtain_group was intended to be able to find an already existing group. Nothing uses that functionality. This just renames it to fsnotify_alloc_group so it is clear what it is doing. Signed-off-by:
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