1. 02 11月, 2011 1 次提交
  2. 05 1月, 2011 1 次提交
  3. 29 10月, 2010 1 次提交
  4. 15 10月, 2010 1 次提交
    • A
      llseek: automatically add .llseek fop · 6038f373
      Arnd Bergmann 提交于
      All file_operations should get a .llseek operation so we can make
      nonseekable_open the default for future file operations without a
      .llseek pointer.
      
      The three cases that we can automatically detect are no_llseek, seq_lseek
      and default_llseek. For cases where we can we can automatically prove that
      the file offset is always ignored, we use noop_llseek, which maintains
      the current behavior of not returning an error from a seek.
      
      New drivers should normally not use noop_llseek but instead use no_llseek
      and call nonseekable_open at open time.  Existing drivers can be converted
      to do the same when the maintainer knows for certain that no user code
      relies on calling seek on the device file.
      
      The generated code is often incorrectly indented and right now contains
      comments that clarify for each added line why a specific variant was
      chosen. In the version that gets submitted upstream, the comments will
      be gone and I will manually fix the indentation, because there does not
      seem to be a way to do that using coccinelle.
      
      Some amount of new code is currently sitting in linux-next that should get
      the same modifications, which I will do at the end of the merge window.
      
      Many thanks to Julia Lawall for helping me learn to write a semantic
      patch that does all this.
      
      ===== begin semantic patch =====
      // This adds an llseek= method to all file operations,
      // as a preparation for making no_llseek the default.
      //
      // The rules are
      // - use no_llseek explicitly if we do nonseekable_open
      // - use seq_lseek for sequential files
      // - use default_llseek if we know we access f_pos
      // - use noop_llseek if we know we don't access f_pos,
      //   but we still want to allow users to call lseek
      //
      @ open1 exists @
      identifier nested_open;
      @@
      nested_open(...)
      {
      <+...
      nonseekable_open(...)
      ...+>
      }
      
      @ open exists@
      identifier open_f;
      identifier i, f;
      identifier open1.nested_open;
      @@
      int open_f(struct inode *i, struct file *f)
      {
      <+...
      (
      nonseekable_open(...)
      |
      nested_open(...)
      )
      ...+>
      }
      
      @ read disable optional_qualifier exists @
      identifier read_f;
      identifier f, p, s, off;
      type ssize_t, size_t, loff_t;
      expression E;
      identifier func;
      @@
      ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
      {
      <+...
      (
         *off = E
      |
         *off += E
      |
         func(..., off, ...)
      |
         E = *off
      )
      ...+>
      }
      
      @ read_no_fpos disable optional_qualifier exists @
      identifier read_f;
      identifier f, p, s, off;
      type ssize_t, size_t, loff_t;
      @@
      ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off)
      {
      ... when != off
      }
      
      @ write @
      identifier write_f;
      identifier f, p, s, off;
      type ssize_t, size_t, loff_t;
      expression E;
      identifier func;
      @@
      ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
      {
      <+...
      (
        *off = E
      |
        *off += E
      |
        func(..., off, ...)
      |
        E = *off
      )
      ...+>
      }
      
      @ write_no_fpos @
      identifier write_f;
      identifier f, p, s, off;
      type ssize_t, size_t, loff_t;
      @@
      ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off)
      {
      ... when != off
      }
      
      @ fops0 @
      identifier fops;
      @@
      struct file_operations fops = {
       ...
      };
      
      @ has_llseek depends on fops0 @
      identifier fops0.fops;
      identifier llseek_f;
      @@
      struct file_operations fops = {
      ...
       .llseek = llseek_f,
      ...
      };
      
      @ has_read depends on fops0 @
      identifier fops0.fops;
      identifier read_f;
      @@
      struct file_operations fops = {
      ...
       .read = read_f,
      ...
      };
      
      @ has_write depends on fops0 @
      identifier fops0.fops;
      identifier write_f;
      @@
      struct file_operations fops = {
      ...
       .write = write_f,
      ...
      };
      
      @ has_open depends on fops0 @
      identifier fops0.fops;
      identifier open_f;
      @@
      struct file_operations fops = {
      ...
       .open = open_f,
      ...
      };
      
      // use no_llseek if we call nonseekable_open
      ////////////////////////////////////////////
      @ nonseekable1 depends on !has_llseek && has_open @
      identifier fops0.fops;
      identifier nso ~= "nonseekable_open";
      @@
      struct file_operations fops = {
      ...  .open = nso, ...
      +.llseek = no_llseek, /* nonseekable */
      };
      
      @ nonseekable2 depends on !has_llseek @
      identifier fops0.fops;
      identifier open.open_f;
      @@
      struct file_operations fops = {
      ...  .open = open_f, ...
      +.llseek = no_llseek, /* open uses nonseekable */
      };
      
      // use seq_lseek for sequential files
      /////////////////////////////////////
      @ seq depends on !has_llseek @
      identifier fops0.fops;
      identifier sr ~= "seq_read";
      @@
      struct file_operations fops = {
      ...  .read = sr, ...
      +.llseek = seq_lseek, /* we have seq_read */
      };
      
      // use default_llseek if there is a readdir
      ///////////////////////////////////////////
      @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier readdir_e;
      @@
      // any other fop is used that changes pos
      struct file_operations fops = {
      ... .readdir = readdir_e, ...
      +.llseek = default_llseek, /* readdir is present */
      };
      
      // use default_llseek if at least one of read/write touches f_pos
      /////////////////////////////////////////////////////////////////
      @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier read.read_f;
      @@
      // read fops use offset
      struct file_operations fops = {
      ... .read = read_f, ...
      +.llseek = default_llseek, /* read accesses f_pos */
      };
      
      @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier write.write_f;
      @@
      // write fops use offset
      struct file_operations fops = {
      ... .write = write_f, ...
      +	.llseek = default_llseek, /* write accesses f_pos */
      };
      
      // Use noop_llseek if neither read nor write accesses f_pos
      ///////////////////////////////////////////////////////////
      
      @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier read_no_fpos.read_f;
      identifier write_no_fpos.write_f;
      @@
      // write fops use offset
      struct file_operations fops = {
      ...
       .write = write_f,
       .read = read_f,
      ...
      +.llseek = noop_llseek, /* read and write both use no f_pos */
      };
      
      @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier write_no_fpos.write_f;
      @@
      struct file_operations fops = {
      ... .write = write_f, ...
      +.llseek = noop_llseek, /* write uses no f_pos */
      };
      
      @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      identifier read_no_fpos.read_f;
      @@
      struct file_operations fops = {
      ... .read = read_f, ...
      +.llseek = noop_llseek, /* read uses no f_pos */
      };
      
      @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @
      identifier fops0.fops;
      @@
      struct file_operations fops = {
      ...
      +.llseek = noop_llseek, /* no read or write fn */
      };
      ===== End semantic patch =====
      Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      Cc: Julia Lawall <julia@diku.dk>
      Cc: Christoph Hellwig <hch@infradead.org>
      6038f373
  5. 10 8月, 2010 1 次提交
  6. 17 5月, 2010 2 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. 04 3月, 2010 1 次提交
  9. 22 9月, 2009 1 次提交
  10. 21 9月, 2009 1 次提交
  11. 11 9月, 2009 2 次提交
  12. 06 1月, 2009 1 次提交
  13. 25 12月, 2008 1 次提交
  14. 14 11月, 2008 1 次提交
  15. 14 10月, 2008 1 次提交
  16. 14 7月, 2008 1 次提交
  17. 25 1月, 2008 4 次提交
  18. 22 8月, 2007 1 次提交
  19. 10 8月, 2007 1 次提交
  20. 10 5月, 2007 1 次提交
  21. 13 2月, 2007 1 次提交
  22. 06 2月, 2007 1 次提交
  23. 09 12月, 2006 1 次提交
  24. 01 10月, 2006 1 次提交
  25. 27 9月, 2006 2 次提交
    • T
      [PATCH] inode-diet: Eliminate i_blksize from the inode structure · ba52de12
      Theodore Ts'o 提交于
      This eliminates the i_blksize field from struct inode.  Filesystems that want
      to provide a per-inode st_blksize can do so by providing their own getattr
      routine instead of using the generic_fillattr() function.
      
      Note that some filesystems were providing pretty much random (and incorrect)
      values for i_blksize.
      
      [bunk@stusta.de: cleanup]
      [akpm@osdl.org: generic_fillattr() fix]
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      Signed-off-by: NAdrian Bunk <bunk@stusta.de>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      ba52de12
    • T
      [PATCH] inode_diet: Replace inode.u.generic_ip with inode.i_private · 8e18e294
      Theodore Ts'o 提交于
      The following patches reduce the size of the VFS inode structure by 28 bytes
      on a UP x86.  (It would be more on an x86_64 system).  This is a 10% reduction
      in the inode size on a UP kernel that is configured in a production mode
      (i.e., with no spinlock or other debugging functions enabled; if you want to
      save memory taken up by in-core inodes, the first thing you should do is
      disable the debugging options; they are responsible for a huge amount of bloat
      in the VFS inode structure).
      
      This patch:
      
      The filesystem or device-specific pointer in the inode is inside a union,
      which is pretty pointless given that all 30+ users of this field have been
      using the void pointer.  Get rid of the union and rename it to i_private, with
      a comment to explain who is allowed to use the void pointer.  This is just a
      cleanup, but it allows us to reuse the union 'u' for something something where
      the union will actually be used.
      
      [judith@osdl.org: powerpc build fix]
      Signed-off-by: N"Theodore Ts'o" <tytso@mit.edu>
      Signed-off-by: NJudith Lebzelter <judith@osdl.org>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      8e18e294
  26. 20 9月, 2006 2 次提交
  27. 23 6月, 2006 2 次提交
    • A
      [PATCH] s390_hypfs filesystem: get_sb_single() fix · a5cf4b9a
      Andrew Morton 提交于
      Update hypfs for dhowells API changes.
      
      Cc: Pekka Enberg <penberg@cs.helsinki.fi>
      Cc: Ingo Oeser <ioe-lkml@rameria.de>
      Cc: Joern Engel <joern@wohnheim.fh-wedel.de>
      Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
      Cc: Michael Holzheu <holzheu@de.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      a5cf4b9a
    • M
      [PATCH] s390_hypfs filesystem · 24bbb1fa
      Michael Holzheu 提交于
      On zSeries machines there exists an interface which allows the operating
      system to retrieve LPAR hypervisor accounting data.  For example, it is
      possible to get usage data for physical and virtual cpus.  In order to
      provide this information to user space programs, I implemented a new
      virtual Linux file system named 's390_hypfs' using the Linux 2.6 libfs
      framework.  The name 's390_hypfs' stands for 'S390 Hypervisor Filesystem'.
      All the accounting information is put into different virtual files which
      can be accessed from user space.  All data is represented as ASCII strings.
      
      When the file system is mounted the accounting information is retrieved and
      a file system tree is created with the attribute files containing the cpu
      information.  The content of the files remains unchanged until a new update
      is made.  An update can be triggered from user space through writing
      'something' into a special purpose update file.
      
      We create the following directory structure:
      
      <mount-point>/
              update
              cpus/
                      <cpu-id>
                              type
                              mgmtime
                      <cpu-id>
                              ...
              hyp/
                      type
              systems/
                      <lpar-name>
                              cpus/
                                      <cpu-id>
                                              type
                                              mgmtime
                                              cputime
                                              onlinetime
                                      <cpu-id>
                                              ...
                      <lpar-name>
                              cpus/
                                      ...
      
      - update: File to trigger update
      - cpus/: Directory for all physical cpus
      - cpus/<cpu-id>/: Directory for one physical cpu.
      - cpus/<cpu-id>/type: Type name of physical zSeries cpu.
      - cpus/<cpu-id>/mgmtime: Physical-LPAR-management time in microseconds.
      - hyp/: Directory for hypervisor information
      - hyp/type: Typ of hypervisor (currently only 'LPAR Hypervisor')
      - systems/: Directory for all LPARs
      - systems/<lpar-name>/: Directory for one LPAR.
      - systems/<lpar-name>/cpus/<cpu-id>/: Directory for the virtual cpus
      - systems/<lpar-name>/cpus/<cpu-id>/type: Typ of cpu.
      - systems/<lpar-name>/cpus/<cpu-id>/mgmtime:
      Accumulated number of microseconds during which a physical
      CPU was assigned to the logical cpu and the cpu time was
      consumed by the hypervisor and was not provided to
      the LPAR (LPAR overhead).
      
      - systems/<lpar-name>/cpus/<cpu-id>/cputime:
      Accumulated number of microseconds during which a physical CPU
      was assigned to the logical cpu and the cpu time was consumed
      by the LPAR.
      
      - systems/<lpar-name>/cpus/<cpu-id>/onlinetime:
      Accumulated number of microseconds during which the logical CPU
      has been online.
      
      As mount point for the filesystem /sys/hypervisor/s390 is created.
      
      The update process is triggered when writing 'something' into the
      'update' file at the top level hypfs directory. You can do this e.g.
      with 'echo 1 > update'. During the update the whole directory structure
      is deleted and built up again.
      
      Cc: Pekka Enberg <penberg@cs.helsinki.fi>
      Cc: Ingo Oeser <ioe-lkml@rameria.de>
      Cc: Joern Engel <joern@wohnheim.fh-wedel.de>
      Acked-by: NMartin Schwidefsky <schwidefsky@de.ibm.com>
      Signed-off-by: NMichael Holzheu <holzheu@de.ibm.com>
      Signed-off-by: NAndrew Morton <akpm@osdl.org>
      Signed-off-by: NLinus Torvalds <torvalds@osdl.org>
      24bbb1fa