1. 10 8月, 2010 1 次提交
  2. 27 7月, 2010 3 次提交
  3. 05 6月, 2010 2 次提交
  4. 28 5月, 2010 1 次提交
  5. 22 5月, 2010 8 次提交
    • E
      sysfs: Implement sysfs tagged directory support. · 3ff195b0
      Eric W. Biederman 提交于
      The problem.  When implementing a network namespace I need to be able
      to have multiple network devices with the same name.  Currently this
      is a problem for /sys/class/net/*, /sys/devices/virtual/net/*, and
      potentially a few other directories of the form /sys/ ... /net/*.
      
      What this patch does is to add an additional tag field to the
      sysfs dirent structure.  For directories that should show different
      contents depending on the context such as /sys/class/net/, and
      /sys/devices/virtual/net/ this tag field is used to specify the
      context in which those directories should be visible.  Effectively
      this is the same as creating multiple distinct directories with
      the same name but internally to sysfs the result is nicer.
      
      I am calling the concept of a single directory that looks like multiple
      directories all at the same path in the filesystem tagged directories.
      
      For the networking namespace the set of directories whose contents I need
      to filter with tags can depend on the presence or absence of hotplug
      hardware or which modules are currently loaded.  Which means I need
      a simple race free way to setup those directories as tagged.
      
      To achieve a reace free design all tagged directories are created
      and managed by sysfs itself.
      
      Users of this interface:
      - define a type in the sysfs_tag_type enumeration.
      - call sysfs_register_ns_types with the type and it's operations
      - sysfs_exit_ns when an individual tag is no longer valid
      
      - Implement mount_ns() which returns the ns of the calling process
        so we can attach it to a sysfs superblock.
      - Implement ktype.namespace() which returns the ns of a syfs kobject.
      
      Everything else is left up to sysfs and the driver layer.
      
      For the network namespace mount_ns and namespace() are essentially
      one line functions, and look to remain that.
      
      Tags are currently represented a const void * pointers as that is
      both generic, prevides enough information for equality comparisons,
      and is trivial to create for current users, as it is just the
      existing namespace pointer.
      
      The work needed in sysfs is more extensive.  At each directory
      or symlink creating I need to check if the directory it is being
      created in is a tagged directory and if so generate the appropriate
      tag to place on the sysfs_dirent.  Likewise at each symlink or
      directory removal I need to check if the sysfs directory it is
      being removed from is a tagged directory and if so figure out
      which tag goes along with the name I am deleting.
      
      Currently only directories which hold kobjects, and
      symlinks are supported.  There is not enough information
      in the current file attribute interfaces to give us anything
      to discriminate on which makes it useless, and there are
      no potential users which makes it an uninteresting problem
      to solve.
      Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
      Signed-off-by: NBenjamin Thery <benjamin.thery@bull.net>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      3ff195b0
    • C
      sysfs: add struct file* to bin_attr callbacks · 2c3c8bea
      Chris Wright 提交于
      This allows bin_attr->read,write,mmap callbacks to check file specific data
      (such as inode owner) as part of any privilege validation.
      Signed-off-by: NChris Wright <chrisw@sous-sol.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      2c3c8bea
    • E
      sysfs: Remove usage of S_BIAS to avoid merge conflict with the vfs tree · 68d75ed4
      Eric W. Biederman 提交于
      In Al's latest vfs tree the code is reworked and S_BIAS has been removed.
      
      It turns out that checking to see if a super block is in the
      middle of an unmount in sysfs_exit_ns is unnecessary because we
      remove the super_block from the s_supers/s_instances list before
      struct sysfs_super_info pointed to by sb->s_fs_info is freed.
      
      For now just delete the unnecessary check to see if a superblock is in the
      middle of an unmount, it isn't necessary with or without Al's changes
      and it just causes a needless conflict.
      Reported-by: NStephen Rothwell <sfr@canb.auug.org.au>
      Cc: Al Viro <viro@zeniv.linux.org.uk>
      Signed-off-by: NEric W. Biederman <ebiederm@aristanetworks.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      68d75ed4
    • E
      ba514a57
    • S
      sysfs: Comment sysfs directory tagging logic · be867b19
      Serge E. Hallyn 提交于
      Add some in-line comments to explain the new infrastructure, which
      was introduced to support sysfs directory tagging with namespaces.
      I think an overall description someplace might be good too, but it
      didn't really seem to fit into Documentation/filesystems/sysfs.txt,
      which appears more geared toward users, rather than maintainers, of
      sysfs.
      
      (Tejun, please let me know if I can make anything clearer or failed
      altogether to comment something that should be commented.)
      Signed-off-by: NSerge E. Hallyn <serue@us.ibm.com>
      Cc: Eric W. Biederman <ebiederm@xmission.com>
      Cc: Tejun Heo <tj@kernel.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      be867b19
    • E
      sysfs: Implement sysfs_delete_link · 746edb7a
      Eric W. Biederman 提交于
      When removing a symlink sysfs_remove_link does not provide
      enough information to figure out which tagged directory the symlink
      falls in.  So I need sysfs_delete_link which is passed the target
      of the symlink to delete.
      
      sysfs_rename_link is updated to call sysfs_delete_link instead
      of sysfs_remove_link as we have all of the information necessary
      and the callers are interesting.
      
      Both of these functions now have enough information to find a symlink
      in a tagged directory.  The only restriction is that they must be called
      before the target kobject is renamed or deleted.  If they are called
      later I loose track of which tag the target kobject was marked with
      and can no longer find the old symlink to remove it.
      
      This patch was split from an earlier patch.
      Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
      Signed-off-by: NBenjamin Thery <benjamin.thery@bull.net>
      Signed-off-by: NDaniel Lezcano <dlezcano@fr.ibm.com>
      Acked-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      746edb7a
    • E
      sysfs: Add support for tagged directories with untagged members. · af10ec77
      Eric W. Biederman 提交于
      I had hopped to avoid this but the bonding driver adds a file
      to /sys/class/net/  and the easiest way to handle that file is
      to make it untagged and to register it only once.
      
      So relax the rules on tagged directories, and make bonding work.
      Signed-off-by: NEric W. Biederman <ebiederm@aristanetworks.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      af10ec77
    • E
      sysfs: Basic support for multiple super blocks · 9e7fdd25
      Eric W. Biederman 提交于
      Add all of the necessary bioler plate to support
      multiple superblocks in sysfs.
      Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
      Acked-by: NSerge Hallyn <serue@us.ibm.com>
      Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      9e7fdd25
  6. 16 5月, 2010 1 次提交
  7. 30 3月, 2010 1 次提交
    • T
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking... · 5a0e3ad6
      Tejun Heo 提交于
      include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
      
      percpu.h is included by sched.h and module.h and thus ends up being
      included when building most .c files.  percpu.h includes slab.h which
      in turn includes gfp.h making everything defined by the two files
      universally available and complicating inclusion dependencies.
      
      percpu.h -> slab.h dependency is about to be removed.  Prepare for
      this change by updating users of gfp and slab facilities include those
      headers directly instead of assuming availability.  As this conversion
      needs to touch large number of source files, the following script is
      used as the basis of conversion.
      
        http://userweb.kernel.org/~tj/misc/slabh-sweep.py
      
      The script does the followings.
      
      * Scan files for gfp and slab usages and update includes such that
        only the necessary includes are there.  ie. if only gfp is used,
        gfp.h, if slab is used, slab.h.
      
      * When the script inserts a new include, it looks at the include
        blocks and try to put the new include such that its order conforms
        to its surrounding.  It's put in the include block which contains
        core kernel includes, in the same order that the rest are ordered -
        alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
        doesn't seem to be any matching order.
      
      * If the script can't find a place to put a new include (mostly
        because the file doesn't have fitting include block), it prints out
        an error message indicating which .h file needs to be added to the
        file.
      
      The conversion was done in the following steps.
      
      1. The initial automatic conversion of all .c files updated slightly
         over 4000 files, deleting around 700 includes and adding ~480 gfp.h
         and ~3000 slab.h inclusions.  The script emitted errors for ~400
         files.
      
      2. Each error was manually checked.  Some didn't need the inclusion,
         some needed manual addition while adding it to implementation .h or
         embedding .c file was more appropriate for others.  This step added
         inclusions to around 150 files.
      
      3. The script was run again and the output was compared to the edits
         from #2 to make sure no file was left behind.
      
      4. Several build tests were done and a couple of problems were fixed.
         e.g. lib/decompress_*.c used malloc/free() wrappers around slab
         APIs requiring slab.h to be added manually.
      
      5. The script was run on all .h files but without automatically
         editing them as sprinkling gfp.h and slab.h inclusions around .h
         files could easily lead to inclusion dependency hell.  Most gfp.h
         inclusion directives were ignored as stuff from gfp.h was usually
         wildly available and often used in preprocessor macros.  Each
         slab.h inclusion directive was examined and added manually as
         necessary.
      
      6. percpu.h was updated not to include slab.h.
      
      7. Build test were done on the following configurations and failures
         were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
         distributed build env didn't work with gcov compiles) and a few
         more options had to be turned off depending on archs to make things
         build (like ipr on powerpc/64 which failed due to missing writeq).
      
         * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
         * powerpc and powerpc64 SMP allmodconfig
         * sparc and sparc64 SMP allmodconfig
         * ia64 SMP allmodconfig
         * s390 SMP allmodconfig
         * alpha SMP allmodconfig
         * um on x86_64 SMP allmodconfig
      
      8. percpu.h modifications were reverted so that it could be applied as
         a separate patch and serve as bisection point.
      
      Given the fact that I had only a couple of failures from tests on step
      6, I'm fairly confident about the coverage of this conversion patch.
      If there is a breakage, it's likely to be something in one of the arch
      headers which should be easily discoverable easily on most builds of
      the specific arch.
      Signed-off-by: NTejun Heo <tj@kernel.org>
      Guess-its-ok-by: NChristoph Lameter <cl@linux-foundation.org>
      Cc: Ingo Molnar <mingo@redhat.com>
      Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
      5a0e3ad6
  8. 08 3月, 2010 11 次提交
  9. 17 2月, 2010 1 次提交
  10. 05 1月, 2010 1 次提交
    • E
      sysfs: Add lockdep annotations for the sysfs active reference · 846f9974
      Eric W. Biederman 提交于
      Holding locks over device_del -> kobject_del -> sysfs_deactivate can
      cause deadlocks if those same locks are grabbed in sysfs show or store
      methods.
      
      The I model s_active count + completion as a sleeping read/write lock.
      I describe to lockdep sysfs_get_active as a read_trylock,
      sysfs_put_active as a read_unlock, and sysfs_deactivate as a
      write_lock and write_unlock pair.  This seems to capture the essence
      for purposes of finding deadlocks, and in my testing gives finds real
      issues and ignores non-issues.
      
      This brings us back to holding locks over kobject_del is a problem
      that ideally we should find a way of addressing, but at least lockdep
      can tell us about the problems instead of requiring developers to debug
      rare strange system deadlocks, that happen when sysfs files are removed
      while being written to.
      Signed-off-by: NEric W. Biederman <ebiederm@xmission.com>
      Acked-by: NTejun Heo <tj@kernel.org>
      Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      846f9974
  11. 24 12月, 2009 1 次提交
  12. 12 12月, 2009 9 次提交