doc: fix misspellings with 'codespell' tool

      The DRM core includes two memory managers, namely Translation Table Maps

      (TTM) and Graphics Execution Manager (GEM). TTM was the first DRM memory

      manager to be developed and tried to be a one-size-fits-them all

      solution. It provides a single userspace API to accomodate the need of

      solution. It provides a single userspace API to accommodate the need of

      all hardware, supporting both Unified Memory Architecture (UMA) devices

      and devices with dedicated video RAM (i.e. most discrete video cards).

      This resulted in a large, complex piece of code that turned out to be

        <para>

          Similar to global names, GEM file descriptors are also used to share GEM

          objects across processes. They offer additional security: as file

          descriptors must be explictly sent over UNIX domain sockets to be shared

          descriptors must be explicitly sent over UNIX domain sockets to be shared

          between applications, they can't be guessed like the globally unique GEM

          names.

        </para>

          </para>

          <para>

            The <methodname>page_flip</methodname> operation schedules a page flip.

            Once any pending rendering targetting the new frame buffer has

            Once any pending rendering targeting the new frame buffer has

            completed, the CRTC will be reprogrammed to display that frame buffer

            after the next vertical refresh. The operation must return immediately

            without waiting for rendering or page flip to complete and must block

<entry align="char">The frontend FEC inner coding (Viterbi, LDPC or other inner code) is stable</entry>

</row><row>

<entry align="char">FE_HAS_SYNC</entry>

<entry align="char">Syncronization bytes was found</entry>

<entry align="char">Synchronization bytes was found</entry>

</row><row>

<entry align="char">FE_HAS_LOCK</entry>

<entry align="char">The DVB were locked and everything is working</entry>

		  <entry>A multi-zone metering. The light intensity is measured

in several points of the frame and the the results are combined. The

algorithm of the zones selection and their significance in calculating the

final value is device dependant.</entry>

final value is device dependent.</entry>

		</row>

	      </tbody>

	    </entrytbl>

  </para>

  <para>

      Because each different protocol causes a new driver to be created, I have

      written a generic USB driver skeleton, modeled after the pci-skeleton.c

      written a generic USB driver skeleton, modelled after the pci-skeleton.c

      file in the kernel source tree upon which many PCI network drivers have

      been based. This USB skeleton can be found at drivers/usb/usb-skeleton.c

      in the kernel source tree. In this article I will walk through the basics

   In practice this isn't an issue because as soon as a write comes along it'll

   cause the btree node to be split, and you need almost no write traffic for

   this to not show up enough to be noticable (especially since bcache's btree

   this to not show up enough to be noticeable (especially since bcache's btree

   nodes are huge and index large regions of the device). But when you're

   benchmarking, if you're trying to warm the cache by reading a bunch of data

   and there's no other traffic - that can be a problem.

  it's in passthrough mode or caching).

sequential_cutoff

  A sequential IO will bypass the cache once it passes this threshhold; the

  A sequential IO will bypass the cache once it passes this threshold; the

  most recent 128 IOs are tracked so sequential IO can be detected even when

  it isn't all done at once.

  since the synchronization for cache misses was rewritten)

cache_readaheads

  Count of times readahead occured.

  Count of times readahead occurred.

SYSFS - CACHE SET:

SYSFS - CACHE SET INTERNAL:

This directory also exposes timings for a number of internal operations, with

separate files for average duration, average frequency, last occurence and max

separate files for average duration, average frequency, last occurrence and max

duration: garbage collection, btree read, btree node sorts and btree splits.

active_journal_entries

  space.

io_errors

  Number of errors that have occured, decayed by io_error_halflife.

  Number of errors that have occurred, decayed by io_error_halflife.

metadata_written

  Sum of all non data writes (btree writes and all other metadata).