1. 19 11月, 2010 1 次提交
  2. 17 11月, 2010 2 次提交
    • F
    • B
      cfg80211: Add nl80211 antenna configuration · afe0cbf8
      Bruno Randolf 提交于
      Allow setting of TX and RX antennas configuration via nl80211.
      
      The antenna configuration is defined as a bitmap of allowed antennas to use.
      This API can be used to mask out antennas which are not attached or should not
      be used for other reasons like regulatory concerns or special setups.
      
      Separate bitmaps are used for RX and TX to allow configuring different antennas
      for receiving and transmitting. Each bitmap is 32 bit long, each bit
      representing one antenna, starting with antenna 1 at the first bit. If an
      antenna bit is set, this means the driver is allowed to use this antenna for RX
      or TX respectively; if the bit is not set the hardware is not allowed to use
      this antenna.
      
      Using bitmaps has the benefit of allowing for a flexible configuration
      interface which can support many different configurations and which can be used
      for 802.11n as well as non-802.11n devices. Instead of relying on some hardware
      specific assumptions, drivers can use this information to know which antennas
      are actually attached to the system and derive their capabilities based on
      that.
      
      802.11n devices should enable or disable chains, based on which antennas are
      present (If all antennas belonging to a particular chain are disabled, the
      entire chain should be disabled). HT capabilities (like STBC, TX Beamforming,
      Antenna selection) should be calculated based on the available chains after
      applying the antenna masks. Should a 802.11n device have diversity antennas
      attached to one of their chains, diversity can be enabled or disabled based on
      the antenna information.
      
      Non-802.11n drivers can use the antenna masks to select RX and TX antennas and
      to enable or disable antenna diversity.
      
      While covering chainmasks for 802.11n and the standard "legacy" modes "fixed
      antenna 1", "fixed antenna 2" and "diversity" this API also allows more rare,
      but useful configurations as follows:
      
      1) Send on antenna 1, receive on antenna 2 (or vice versa). This can be used to
      have a low gain antenna for TX in order to keep within the regulatory
      constraints and a high gain antenna for RX in order to receive weaker signals
      ("speak softly, but listen harder"). This can be useful for building long-shot
      outdoor links. Another usage of this setup is having a low-noise pre-amplifier
      on antenna 1 and a power amplifier on the other antenna. This way transmit
      noise is mostly kept out of the low noise receive channel.
      (This would be bitmaps: tx 1 rx 2).
      
      2) Another similar setup is: Use RX diversity on both antennas, but always send
      on antenna 1. Again that would allow us to benefit from a higher gain RX
      antenna, while staying within the legal limits.
      (This would be: tx 0 rx 3).
      
      3) And finally there can be special experimental setups in research and
      development even with pre 802.11n hardware where more than 2 antennas are
      available. It's good to keep the API simple, yet flexible.
      Signed-off-by: NBruno Randolf <br1@einfach.org>
      
      --
      v7:	Made bitmasks 32 bit wide and rebased to latest wireless-testing.
      Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>
      afe0cbf8
  3. 16 11月, 2010 7 次提交
  4. 26 10月, 2010 1 次提交
    • L
      cfg80211: fix regression on processing country IEs · a171fba4
      Luis R. Rodriguez 提交于
      The patch 4f366c5d:
      
      	wireless: only use alpha2 regulatory information from country IE
      
      removed some complex intersection we were always doing between the AP's
      country IE info and what we got from CRDA. When CRDA sent us back a
      regulatory domain we would do some sanity checks on that regulatory
      domain response we just got. Part of these sanity checks included
      checking that we already had performed an intersection for the
      request of NL80211_REGDOM_SET_BY_COUNTRY_IE type.
      
      This mean that cfg80211 was only processing country IEs for cases
      where we already had an intersection, but since we removed enforcing
      this this is no longer required, we should just apply the country
      IE country hint with the data received from CRDA.
      
      This patch has fixes intended for kernels >= 2.6.36.
      
      Cc: stable@kernel.org
      Reported-by: NEaswar Krishnan <easwar.krishnan@atheros.com>
      Signed-off-by: NLuis R. Rodriguez <lrodriguez@atheros.com>
      Signed-off-by: NJohn W. Linville <linville@tuxdriver.com>
      a171fba4
  5. 16 10月, 2010 1 次提交
  6. 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
  7. 14 10月, 2010 1 次提交
  8. 13 10月, 2010 1 次提交
  9. 12 10月, 2010 3 次提交
  10. 08 10月, 2010 2 次提交
  11. 07 10月, 2010 4 次提交
  12. 06 10月, 2010 8 次提交
  13. 29 9月, 2010 1 次提交
  14. 28 9月, 2010 1 次提交
  15. 24 9月, 2010 1 次提交
  16. 21 9月, 2010 1 次提交
  17. 17 9月, 2010 3 次提交
  18. 16 9月, 2010 1 次提交
    • A
      net/wireless: use generic_file_llseek in debugfs · 2b18ab36
      Arnd Bergmann 提交于
      The default llseek operation is changing from
      default_llseek to no_llseek, so all code relying on
      the current behaviour needs to make that explicit.
      
      The wireless driver infrastructure and some of the drivers
      make use of generated debugfs files, so they cannot
      be converted by our script that automatically determines
      the right operation.
      
      All these files use debugfs and they typically rely
      on simple_read_from_buffer, so the best llseek operation
      here is generic_file_llseek.
      Signed-off-by: NArnd Bergmann <arnd@arndb.de>
      Cc: "John W. Linville" <linville@tuxdriver.com>
      Cc: linux-wireless@vger.kernel.org
      Cc: netdev@vger.kernel.org
      2b18ab36