1. 28 Jul, 2010 40 commits
    • Andreas Gruenbacher's avatar
      fanotify: do not call fanotify_update_object_mask in fanotify_remove_mark · 088b09b0
      Andreas Gruenbacher authored
      
      
      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: default avatarAndreas Gruenbacher <agruen@suse.de>
      Signed-off-by: default avatarEric Paris <eparis@redhat.com>
      088b09b0
    • Andreas Gruenbacher's avatar
      fanotify: remove fanotify_update_mark · c6223f46
      Andreas Gruenbacher authored
      
      
      fanotify_update_mark() doesn't do much useful;  remove it.
      Signed-off-by: default avatarAndreas Gruenbacher <agruen@suse.de>
      Signed-off-by: default avatarEric Paris <eparis@redhat.com>
      c6223f46
    • Eric Paris's avatar
      fanotify: infrastructure to add an remove marks on vfsmounts · 88826276
      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: default avatarEric Paris <eparis@redhat.com>
      88826276
    • Eric Paris's avatar
      fanotify: should_send_event needs to handle vfsmounts · 1c529063
      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: default avatarEric Paris <eparis@redhat.com>
      1c529063
    • Andreas Gruenbacher's avatar
      fsnotify: Infrastructure for per-mount watches · ca9c726e
      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: default avatarAndreas Gruenbacher <agruen@suse.de>
      Signed-off-by: default avatarEric Paris <eparis@redhat.com>
      ca9c726e
    • Eric Paris's avatar
      fsnotify: vfsmount marks generic functions · 0d48b7f0
      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: default avatarEric Paris <eparis@redhat.com>
      0d48b7f0
    • Andreas Gruenbacher's avatar
      fsnotify/vfsmount: add fsnotify fields to struct vfsmount · 2504c5d6
      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: default avatarAndreas Gruenbacher <agruen@suse.de>
      Signed-off-by: default avatarEric Paris <eparis@redhat.com>
      2504c5d6
    • Eric Paris's avatar
      fsnotify: clear marks to 0 in fsnotify_init_mark · ba643f04
      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: default avatarEric Paris <eparis@redhat.com>
      ba643f04
    • Eric Paris's avatar
      fsnotify: split generic and inode specific mark code · 5444e298
      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: default avatarEric Paris <eparis@redhat.com>
      5444e298
    • Andreas Gruenbacher's avatar
      fanotify: Add pids to events · 32c32632
      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: default avatarAndreas Gruenbacher <agruen@suse.de>
      Signed-off-by: default avatarEric Paris <eparis@redhat.com>
      32c32632
    • Andreas Gruenbacher's avatar
      fanotify: create_fd cleanup · 22aa425d
      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: default avatarAndreas Gruenbacher <agruen@suse.de>
      Signed-off-by: default avatarEric Paris <eparis@redhat.com>
      22aa425d
    • Heiko Carstens's avatar
      fanotify: CONFIG_HAVE_SYSCALL_WRAPPERS for sys_fanotify_mark · 9bbfc964
      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: default avatarEric Paris <eparis@redhat.com>
      9bbfc964
    • Paul Mundt's avatar
      fanotify: select ANON_INODES. · ef601a9c
      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: default avatarPaul Mundt <lethal@linux-sh.org>
      Signed-off-by: default avatarEric Paris <eparis@redhat.com>
      ef601a9c
    • Eric Paris's avatar
      fanotify: send events using read · a1014f10
      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: default avatarEric Paris <eparis@redhat.com>
      a1014f10
    • Eric Paris's avatar
      fanotify: fanotify_mark syscall implementation · 2a3edf86
      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: default avatarEric Paris <eparis@redhat.com>
      2a3edf86
    • Eric Paris's avatar
      fanotify: sys_fanotify_mark declartion · bbaa4168
      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: default avatarEric Paris <eparis@redhat.com>
      bbaa4168
    • Eric Paris's avatar
      fanotify: fanotify_init syscall implementation · 52c923dd
      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: default avatarEric Paris <eparis@redhat.com>
      52c923dd
    • Eric Paris's avatar
      fanotify: fanotify_init syscall declaration · 11637e4b
      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: default avatarEric Paris <eparis@redhat.com>
      11637e4b
    • Eric Paris's avatar
      fanotify: do not clone on merge unless needed · 9dced01a
      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: default avatarEric Paris <eparis@redhat.com>
      9dced01a
    • Eric Paris's avatar
      fanotify: merge notification events with different masks · a12a7dd3
      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: default avatarEric Paris <eparis@redhat.com>
      a12a7dd3
    • Eric Paris's avatar
      fanotify:drop notification if they exist in the outgoing queue · 767cd46c
      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: default avatarEric Paris <eparis@redhat.com>
      767cd46c
    • Eric Paris's avatar
      fanotify: fscking all notification system · ff0b16a9
      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: default avatarEric Paris <eparis@redhat.com>
      ff0b16a9
    • Signed-off-by: Wu Fengguang's avatar
      fanotify: FMODE_NONOTIFY and __O_SYNC in sparc conflict · 12ed2e36
      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: default avatarWu Fengguang <fengguang.wu@intel.com>
      Signed-off-by: default avatarEric Paris <eparis@redhat.com>
      12ed2e36
    • Eric Paris's avatar
      vfs: introduce FMODE_NONOTIFY · ecf081d1
      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: default avatarEric Paris <eparis@redhat.com>
      ecf081d1
    • Andreas Gruenbacher's avatar
      fsnotify: take inode->i_lock inside fsnotify_find_mark_entry() · 35566087
      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: default avatarAndreas Gruenbacher <agruen@suse.de>
      Signed-off-by: default avatarEric Paris <eparis@redhat.com>
      35566087
    • Eric Paris's avatar
      dnotify: rename mark_entry to mark · ef5e2b78
      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: default avatarEric Paris <eparis@redhat.com>
      ef5e2b78
    • Eric Paris's avatar
      inotify: rename mark_entry to just mark · 000285de
      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: default avatarEric Paris <eparis@redhat.com>
      000285de
    • Eric Paris's avatar
      fsnotify: rename mark_entry to just mark · 841bdc10
      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: default avatarEric Paris <eparis@redhat.com>
      841bdc10
    • Eric Paris's avatar
      fsnotify: rename fsnotify_find_mark_entry to fsnotify_find_mark · d0775441
      Eric Paris authored
      
      
      the _entry portion of fsnotify functions is useless.  Drop it.
      Signed-off-by: default avatarEric Paris <eparis@redhat.com>
      d0775441
    • Eric Paris's avatar
      fsnotify: rename fsnotify_mark_entry to just fsnotify_mark · e61ce867
      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: default avatarEric Paris <eparis@redhat.com>
      e61ce867
    • Andreas Gruenbacher's avatar
      fsnotify: kill FSNOTIFY_EVENT_FILE · 72acc854
      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: default avatarAndreas Gruenbacher <agruen@suse.de>
      Signed-off-by: default avatarEric Paris <eparis@redhat.com>
      72acc854
    • Eric Paris's avatar
      fsnotify: add flags to fsnotify_mark_entries · 098cf2fc
      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: default avatarEric Paris <eparis@redhat.com>
      098cf2fc
    • Eric Paris's avatar
      fsnotify: add vfsmount specific fields to the fsnotify_mark_entry union · 4136510d
      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: default avatarEric Paris <eparis@redhat.com>
      4136510d
    • Eric Paris's avatar
      fsnotify: put inode specific fields in an fsnotify_mark in a union · 2823e04d
      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: default avatarEric Paris <eparis@redhat.com>
      2823e04d
    • Eric Paris's avatar
      fsnotify: include vfsmount in should_send_event when appropriate · 3a9fb89f
      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: default avatarEric Paris <eparis@redhat.com>
      3a9fb89f
    • Eric Paris's avatar
      fsnotify: mount point listeners list and global mask · 7131485a
      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: default avatarEric Paris <eparis@redhat.com>
      7131485a
    • Eric Paris's avatar
      fsnotify: add groups to fsnotify_inode_groups when registering inode watch · 4ca76352
      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: default avatarEric Paris <eparis@redhat.com>
      4ca76352
    • Eric Paris's avatar
      fsnotify: initialize the group->num_marks in a better place · 36fddeba
      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: default avatarEric Paris <eparis@redhat.com>
      36fddeba
    • Eric Paris's avatar
      fsnotify: rename fsnotify_groups to fsnotify_inode_groups · 19c2a0e1
      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: default avatarEric Paris <eparis@redhat.com>
      19c2a0e1
    • Eric Paris's avatar
      fsnotify: drop mask argument from fsnotify_alloc_group · 0d2e2a1d
      Eric Paris authored
      
      
      Nothing uses the mask argument to fsnotify_alloc_group.  This patch drops
      that argument.
      Signed-off-by: default avatarEric Paris <eparis@redhat.com>
      0d2e2a1d