1. 18 4月, 2013 2 次提交
  2. 17 4月, 2013 4 次提交
  3. 28 2月, 2013 1 次提交
  4. 04 2月, 2013 1 次提交
    • E
      fuse: avoid out-of-scope stack access · 6a4e922c
      Eric Wong 提交于
      The all pointers within fuse_req must point to valid memory once
      fuse_force_forget() returns.
      
      This bug appeared in "fuse: implement NFS-like readdirplus support"
      and was never in any official Linux release.
      
      I tested the fuse_force_forget() code path by injecting to fake -ENOMEM and
      verified the FORGET operation was called properly in userspace.
      Signed-off-by: NEric Wong <normalperson@yhbt.net>
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      6a4e922c
  5. 24 1月, 2013 6 次提交
    • M
      fuse: use req->page_descs[] for argpages cases · 85f40aec
      Maxim Patlasov 提交于
      Previously, anyone who set flag 'argpages' only filled req->pages[] and set
      per-request page_offset. This patch re-works all cases where argpages=1 to
      fill req->page_descs[] properly.
      
      Having req->page_descs[] filled properly allows to re-work fuse_copy_pages()
      to copy page fragments described by req->page_descs[]. This will be useful
      for next patches optimizing direct_IO.
      Signed-off-by: NMaxim Patlasov <mpatlasov@parallels.com>
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      85f40aec
    • M
      fuse: add per-page descriptor <offset, length> to fuse_req · b2430d75
      Maxim Patlasov 提交于
      The ability to save page pointers along with lengths and offsets in fuse_req
      will be useful to cover several iovec-s with a single fuse_req.
      
      Per-request page_offset is removed because anybody who need it can use
      req->page_descs[0].offset instead.
      Signed-off-by: NMaxim Patlasov <mpatlasov@parallels.com>
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      b2430d75
    • M
      fuse: rework fuse_retrieve() · 4d53dc99
      Maxim Patlasov 提交于
      The patch reworks fuse_retrieve() to allocate only so many page pointers
      as needed. The core part of the patch is the following calculation:
      
      	num_pages = (num + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;
      
      (thanks Miklos for formula). All other changes are mostly shuffling lines.
      Signed-off-by: NMaxim Patlasov <mpatlasov@parallels.com>
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      4d53dc99
    • M
      fuse: categorize fuse_get_req() · b111c8c0
      Maxim Patlasov 提交于
      The patch categorizes all fuse_get_req() invocations into two categories:
       - fuse_get_req_nopages(fc) - when caller doesn't care about req->pages
       - fuse_get_req(fc, n) - when caller need n page pointers (n > 0)
      
      Adding fuse_get_req_nopages() helps to avoid numerous fuse_get_req(fc, 0)
      scattered over code. Now it's clear from the first glance when a caller need
      fuse_req with page pointers.
      
      The patch doesn't make any logic changes. In multi-page case, it silly
      allocates array of FUSE_MAX_PAGES_PER_REQ page pointers. This will be amended
      by future patches.
      Signed-off-by: NMaxim Patlasov <mpatlasov@parallels.com>
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      b111c8c0
    • M
      fuse: general infrastructure for pages[] of variable size · 4250c066
      Maxim Patlasov 提交于
      The patch removes inline array of FUSE_MAX_PAGES_PER_REQ page pointers from
      fuse_req. Instead of that, req->pages may now point either to small inline
      array or to an array allocated dynamically.
      
      This essentially means that all callers of fuse_request_alloc[_nofs] should
      pass the number of pages needed explicitly.
      
      The patch doesn't make any logic changes.
      Signed-off-by: NMaxim Patlasov <mpatlasov@parallels.com>
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      4250c066
    • A
      fuse: implement NFS-like readdirplus support · 0b05b183
      Anand V. Avati 提交于
      This patch implements readdirplus support in FUSE, similar to NFS.
      The payload returned in the readdirplus call contains
      'fuse_entry_out' structure thereby providing all the necessary inputs
      for 'faking' a lookup() operation on the spot.
      
      If the dentry and inode already existed (for e.g. in a re-run of ls -l)
      then just the inode attributes timeout and dentry timeout are refreshed.
      
      With a simple client->network->server implementation of a FUSE based
      filesystem, the following performance observations were made:
      
      Test: Performing a filesystem crawl over 20,000 files with
      
      sh# time ls -lR /mnt
      
      Without readdirplus:
      Run 1: 18.1s
      Run 2: 16.0s
      Run 3: 16.2s
      
      With readdirplus:
      Run 1: 4.1s
      Run 2: 3.8s
      Run 3: 3.8s
      
      The performance improvement is significant as it avoided 20,000 upcalls
      calls (lookup). Cache consistency is no worse than what already is.
      Signed-off-by: NAnand V. Avati <avati@redhat.com>
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      0b05b183
  6. 17 1月, 2013 1 次提交
  7. 15 11月, 2012 1 次提交
    • E
      userns: Support fuse interacting with multiple user namespaces · 499dcf20
      Eric W. Biederman 提交于
      Use kuid_t and kgid_t in struct fuse_conn and struct fuse_mount_data.
      
      The connection between between a fuse filesystem and a fuse daemon is
      established when a fuse filesystem is mounted and provided with a file
      descriptor the fuse daemon created by opening /dev/fuse.
      
      For now restrict the communication of uids and gids between the fuse
      filesystem and the fuse daemon to the initial user namespace.  Enforce
      this by verifying the file descriptor passed to the mount of fuse was
      opened in the initial user namespace.  Ensuring the mount happens in
      the initial user namespace is not necessary as mounts from non-initial
      user namespaces are not yet allowed.
      
      In fuse_req_init_context convert the currrent fsuid and fsgid into the
      initial user namespace for the request that will be sent to the fuse
      daemon.
      
      In fuse_fill_attr convert the uid and gid passed from the fuse daemon
      from the initial user namespace into kuids and kgids.
      
      In iattr_to_fattr called from fuse_setattr convert kuids and kgids
      into the uids and gids in the initial user namespace before passing
      them to the fuse filesystem.
      
      In fuse_change_attributes_common called from fuse_dentry_revalidate,
      fuse_permission, fuse_geattr, and fuse_setattr, and fuse_iget convert
      the uid and gid from the fuse daemon into a kuid and a kgid to store
      on the fuse inode.
      
      By default fuse mounts are restricted to task whose uid, suid, and
      euid matches the fuse user_id and whose gid, sgid, and egid matches
      the fuse group id.  Convert the user_id and group_id mount options
      into kuids and kgids at mount time, and use uid_eq and gid_eq to
      compare the in fuse_allow_task.
      
      Cc: Miklos Szeredi <miklos@szeredi.hu>
      Acked-by: NSerge Hallyn <serge.hallyn@canonical.com>
      Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
      499dcf20
  8. 27 9月, 2012 1 次提交
  9. 05 9月, 2012 1 次提交
  10. 20 3月, 2012 1 次提交
  11. 13 12月, 2011 2 次提交
    • J
      FUSE: Notifying the kernel of deletion. · 451d0f59
      John Muir 提交于
      Allows a FUSE file-system to tell the kernel when a file or directory is
      deleted. If the specified dentry has the specified inode number, the kernel will
      unhash it.
      
      The current 'fuse_notify_inval_entry' does not cause the kernel to clean up
      directories that are in use properly, and as a result the users of those
      directories see incorrect semantics from the file-system. The error condition
      seen when 'fuse_notify_inval_entry' is used to notify of a deleted directory is
      avoided when 'fuse_notify_delete' is used instead.
      
      The following scenario demonstrates the difference:
      1. User A chdirs into 'testdir' and starts reading 'testfile'.
      2. User B rm -rf 'testdir'.
      3. User B creates 'testdir'.
      4. User C chdirs into 'testdir'.
      
      If you run the above within the same machine on any file-system (including fuse
      file-systems), there is no problem: user C is able to chdir into the new
      testdir. The old testdir is removed from the dentry tree, but still open by user
      A.
      
      If operations 2 and 3 are performed via the network such that the fuse
      file-system uses one of the notify functions to tell the kernel that the nodes
      are gone, then the following error occurs for user C while user A holds the
      original directory open:
      
      muirj@empacher:~> ls /test/testdir
      ls: cannot access /test/testdir: No such file or directory
      
      The issue here is that the kernel still has a dentry for testdir, and so it is
      requesting the attributes for the old directory, while the file-system is
      responding that the directory no longer exists.
      
      If on the other hand, if the file-system can notify the kernel that the
      directory is deleted using the new 'fuse_notify_delete' function, then the above
      ls will find the new directory as expected.
      Signed-off-by: NJohn Muir <john@jmuir.com>
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      451d0f59
    • M
      fuse: fix fuse_retrieve · 48706d0a
      Miklos Szeredi 提交于
      Fix two bugs in fuse_retrieve():
      
       - retrieving more than one page would yield repeated instances of the
         first page
      
       - if more than FUSE_MAX_PAGES_PER_REQ pages were requested than the
         request page array would overflow
      
      fuse_retrieve() was added in 2.6.36 and these bugs had been there since the
      beginning.
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      CC: stable@vger.kernel.org
      48706d0a
  12. 13 9月, 2011 1 次提交
    • M
      fuse: fix memory leak · 5dfcc87f
      Miklos Szeredi 提交于
      kmemleak is reporting that 32 bytes are being leaked by FUSE:
      
        unreferenced object 0xe373b270 (size 32):
        comm "fusermount", pid 1207, jiffies 4294707026 (age 2675.187s)
        hex dump (first 32 bytes):
          01 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00  ................
          00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
        backtrace:
          [<b05517d7>] kmemleak_alloc+0x27/0x50
          [<b0196435>] kmem_cache_alloc+0xc5/0x180
          [<b02455be>] fuse_alloc_forget+0x1e/0x20
          [<b0245670>] fuse_alloc_inode+0xb0/0xd0
          [<b01b1a8c>] alloc_inode+0x1c/0x80
          [<b01b290f>] iget5_locked+0x8f/0x1a0
          [<b0246022>] fuse_iget+0x72/0x1a0
          [<b02461da>] fuse_get_root_inode+0x8a/0x90
          [<b02465cf>] fuse_fill_super+0x3ef/0x590
          [<b019e56f>] mount_nodev+0x3f/0x90
          [<b0244e95>] fuse_mount+0x15/0x20
          [<b019d1bc>] mount_fs+0x1c/0xc0
          [<b01b5811>] vfs_kern_mount+0x41/0x90
          [<b01b5af9>] do_kern_mount+0x39/0xd0
          [<b01b7585>] do_mount+0x2e5/0x660
          [<b01b7966>] sys_mount+0x66/0xa0
      
      This leak report is consistent and happens once per boot on
      3.1.0-rc5-dirty.
      
      This happens if a FORGET request is queued after the fuse device was
      released.
      Reported-by: NSitsofe Wheeler <sitsofe@yahoo.com>
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      Tested-by: NSitsofe Wheeler <sitsofe@yahoo.com>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      5dfcc87f
  13. 24 8月, 2011 1 次提交
  14. 23 3月, 2011 1 次提交
  15. 21 3月, 2011 1 次提交
  16. 08 12月, 2010 2 次提交
    • M
      fuse: allow batching of FORGET requests · 02c048b9
      Miklos Szeredi 提交于
      Terje Malmedal reports that a fuse filesystem with 32 million inodes
      on a machine with lots of memory can take up to 30 minutes to process
      FORGET requests when all those inodes are evicted from the icache.
      
      To solve this, create a BATCH_FORGET request that allows up to about
      8000 FORGET requests to be sent in a single message.
      
      This request is only sent if userspace supports interface version 7.16
      or later, otherwise fall back to sending individual FORGET messages.
      Reported-by: NTerje Malmedal <terje.malmedal@usit.uio.no>
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      02c048b9
    • M
      fuse: separate queue for FORGET requests · 07e77dca
      Miklos Szeredi 提交于
      Terje Malmedal reports that a fuse filesystem with 32 million inodes
      on a machine with lots of memory can go unresponsive for up to 30
      minutes when all those inodes are evicted from the icache.
      
      The reason is that FORGET messages, sent when the inode is evicted,
      are queued up together with regular filesystem requests, and while the
      huge queue of FORGET messages are processed no other filesystem
      operation can proceed.
      
      Since a full fuse request structure is allocated for each inode, these
      take up quite a bit of memory as well.
      
      To solve these issues, create a slim 'fuse_forget_link' structure
      containing just the minimum of information required to send the FORGET
      request and chain these on a separate queue.
      
      When userspace is asking for a request make sure that FORGET and
      non-FORGET requests are selected fairly: for each 8 non-FORGET allow
      16 FORGET requests.  This will make sure FORGETs do not pile up, yet
      other requests are also allowed to proceed while the queued FORGETs
      are processed.
      Reported-by: NTerje Malmedal <terje.malmedal@usit.uio.no>
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      07e77dca
  17. 28 10月, 2010 1 次提交
  18. 27 10月, 2010 2 次提交
  19. 04 10月, 2010 1 次提交
  20. 07 9月, 2010 2 次提交
    • M
      fuse: fix lock annotations · b9ca67b2
      Miklos Szeredi 提交于
      Sparse doesn't understand lock annotations of the form
      __releases(&foo->lock).  Change them to __releases(foo->lock).  Same
      for __acquires().
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      b9ca67b2
    • M
      fuse: flush background queue on connection close · 595afaf9
      Miklos Szeredi 提交于
      David Bartly reported that fuse can hang in fuse_get_req_nofail() when
      the connection to the filesystem server is no longer active.
      
      If bg_queue is not empty then flush_bg_queue() called from
      request_end() can put more requests on to the pending queue.  If this
      happens while ending requests on the processing queue then those
      background requests will be queued to the pending list and never
      ended.
      
      Another problem is that fuse_dev_release() didn't wake up processes
      sleeping on blocked_waitq.
      
      Solve this by:
      
       a) flushing the background queue before calling end_requests() on the
          pending and processing queues
      
       b) setting blocked = 0 and waking up processes waiting on
          blocked_waitq()
      
      Thanks to David for an excellent bug report.
      Reported-by: NDavid Bartley <andareed@gmail.com>
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      CC: stable@kernel.org
      595afaf9
  21. 12 7月, 2010 3 次提交
    • M
      fuse: add retrieve request · 2d45ba38
      Miklos Szeredi 提交于
      Userspace filesystem can request data to be retrieved from the inode's
      mapping.  This request is synchronous and the retrieved data is queued
      as a new request.  If the write to the fuse device returns an error
      then the retrieve request was not completed and a reply will not be
      sent.
      
      Only present pages are returned in the retrieve reply.  Retrieving
      stops when it finds a non-present page and only data prior to that is
      returned.
      
      This request doesn't change the dirty state of pages.
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      2d45ba38
    • M
      fuse: add store request · a1d75f25
      Miklos Szeredi 提交于
      Userspace filesystem can request data to be stored in the inode's
      mapping.  This request is synchronous and has no reply.  If the write
      to the fuse device returns an error then the store request was not
      fully completed (but may have updated some pages).
      
      If the stored data overflows the current file size, then the size is
      extended, similarly to a write(2) on the filesystem.
      
      Pages which have been completely stored are marked uptodate.
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      a1d75f25
    • M
      fuse: don't use atomic kmap · 7909b1c6
      Miklos Szeredi 提交于
      Don't use atomic kmap for mapping userspace buffers in device
      read/write/splice.
      
      This is necessary because the next patch (adding store notify)
      requires that caller of fuse_copy_page() may sleep between
      invocations.  The simplest way to ensure this is to change the atomic
      kmaps to non-atomic ones.
      
      Thankfully architectures where kmap() is not a no-op are going out of
      fashion, so we can ignore the (probably negligible) performance impact
      of this change.
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      7909b1c6
  22. 26 5月, 2010 1 次提交
    • K
      driver core: add devname module aliases to allow module on-demand auto-loading · 578454ff
      Kay Sievers 提交于
      This adds:
        alias: devname:<name>
      to some common kernel modules, which will allow the on-demand loading
      of the kernel module when the device node is accessed.
      
      Ideally all these modules would be compiled-in, but distros seems too
      much in love with their modularization that we need to cover the common
      cases with this new facility. It will allow us to remove a bunch of pretty
      useless init scripts and modprobes from init scripts.
      
      The static device node aliases will be carried in the module itself. The
      program depmod will extract this information to a file in the module directory:
        $ cat /lib/modules/2.6.34-00650-g537b60d1-dirty/modules.devname
        # Device nodes to trigger on-demand module loading.
        microcode cpu/microcode c10:184
        fuse fuse c10:229
        ppp_generic ppp c108:0
        tun net/tun c10:200
        dm_mod mapper/control c10:235
      
      Udev will pick up the depmod created file on startup and create all the
      static device nodes which the kernel modules specify, so that these modules
      get automatically loaded when the device node is accessed:
        $ /sbin/udevd --debug
        ...
        static_dev_create_from_modules: mknod '/dev/cpu/microcode' c10:184
        static_dev_create_from_modules: mknod '/dev/fuse' c10:229
        static_dev_create_from_modules: mknod '/dev/ppp' c108:0
        static_dev_create_from_modules: mknod '/dev/net/tun' c10:200
        static_dev_create_from_modules: mknod '/dev/mapper/control' c10:235
        udev_rules_apply_static_dev_perms: chmod '/dev/net/tun' 0666
        udev_rules_apply_static_dev_perms: chmod '/dev/fuse' 0666
      
      A few device nodes are switched to statically allocated numbers, to allow
      the static nodes to work. This might also useful for systems which still run
      a plain static /dev, which is completely unsafe to use with any dynamic minor
      numbers.
      
      Note:
      The devname aliases must be limited to the *common* and *single*instance*
      device nodes, like the misc devices, and never be used for conceptually limited
      systems like the loop devices, which should rather get fixed properly and get a
      control node for losetup to talk to, instead of creating a random number of
      device nodes in advance, regardless if they are ever used.
      
      This facility is to hide the mess distros are creating with too modualized
      kernels, and just to hide that these modules are not compiled-in, and not to
      paper-over broken concepts. Thanks! :)
      
      Cc: Greg Kroah-Hartman <gregkh@suse.de>
      Cc: David S. Miller <davem@davemloft.net>
      Cc: Miklos Szeredi <miklos@szeredi.hu>
      Cc: Chris Mason <chris.mason@oracle.com>
      Cc: Alasdair G Kergon <agk@redhat.com>
      Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
      Cc: Ian Kent <raven@themaw.net>
      Signed-Off-By: NKay Sievers <kay.sievers@vrfy.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      578454ff
  23. 25 5月, 2010 3 次提交
    • M
      fuse: support splice() reading from fuse device · c3021629
      Miklos Szeredi 提交于
      Allow userspace filesystem implementation to use splice() to read from
      the fuse device.
      
      The userspace filesystem can now transfer data coming from a WRITE
      request to an arbitrary file descriptor (regular file, block device or
      socket) without having to go through a userspace buffer.
      
      The semantics of using splice() to read messages are:
      
       1)  with a single splice() call move the whole message from the fuse
           device to a temporary pipe
       2)  read the header from the pipe and determine the message type
       3a) if message is a WRITE then splice data from pipe to destination
       3b) else read rest of message to userspace buffer
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      c3021629
    • M
      fuse: allow splice to move pages · ce534fb0
      Miklos Szeredi 提交于
      When splicing buffers to the fuse device with SPLICE_F_MOVE, try to
      move pages from the pipe buffer into the page cache.  This allows
      populating the fuse filesystem's cache without ever touching the page
      contents, i.e. zero copy read capability.
      
      The following steps are performed when trying to move a page into the
      page cache:
      
       - buf->ops->confirm() to make sure the new page is uptodate
       - buf->ops->steal() to try to remove the new page from it's previous place
       - remove_from_page_cache() on the old page
       - add_to_page_cache_locked() on the new page
      
      If any of the above steps fail (non fatally) then the code falls back
      to copying the page.  In particular ->steal() will fail if there are
      external references (other than the page cache and the pipe buffer) to
      the page.
      
      Also since the remove_from_page_cache() + add_to_page_cache_locked()
      are non-atomic it is possible that the page cache is repopulated in
      between the two and add_to_page_cache_locked() will fail.  This could
      be fixed by creating a new atomic replace_page_cache_page() function.
      
      fuse_readpages_end() needed to be reworked so it works even if
      page->mapping is NULL for some or all pages which can happen if the
      add_to_page_cache_locked() failed.
      
      A number of sanity checks were added to make sure the stolen pages
      don't have weird flags set, etc...  These could be moved into generic
      splice/steal code.
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      ce534fb0
    • M
      fuse: support splice() writing to fuse device · dd3bb14f
      Miklos Szeredi 提交于
      Allow userspace filesystem implementation to use splice() to write to
      the fuse device.  The semantics of using splice() are:
      
       1) buffer the message header and data in a temporary pipe
       2) with a *single* splice() call move the message from the temporary pipe
          to the fuse device
      
      The READ reply message has the most interesting use for this, since
      now the data from an arbitrary file descriptor (which could be a
      regular file, a block device or a socket) can be tranferred into the
      fuse device without having to go through a userspace buffer.  It will
      also allow zero copy moving of pages.
      
      One caveat is that the protocol on the fuse device requires the length
      of the whole message to be written into the header.  But the length of
      the data transferred into the temporary pipe may not be known in
      advance.  The current library implementation works around this by
      using vmplice to write the header and modifying the header after
      splicing the data into the pipe (error handling omitted):
      
      	struct fuse_out_header out;
      
      	iov.iov_base = &out;
      	iov.iov_len = sizeof(struct fuse_out_header);
      	vmsplice(pip[1], &iov, 1, 0);
      	len = splice(input_fd, input_offset, pip[1], NULL, len, 0);
      	/* retrospectively modify the header: */
      	out.len = len + sizeof(struct fuse_out_header);
      	splice(pip[0], NULL, fuse_chan_fd(req->ch), NULL, out.len, flags);
      
      This works since vmsplice only saves a pointer to the data, it does
      not copy the data itself.
      
      Since pipes are currently limited to 16 pages and messages need to be
      spliced atomically, the length of the data is limited to 15 pages (or
      60kB for 4k pages).
      Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      dd3bb14f