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diff --git a/static/freebsd/man9/shm_map.9 4.html b/static/freebsd/man9/shm_map.9 4.html deleted file mode 100644 index 0fd117c8..00000000 --- a/static/freebsd/man9/shm_map.9 4.html +++ /dev/null @@ -1,163 +0,0 @@ -<table class="head"> - <tr> - <td class="head-ltitle">SHM_MAP(9)</td> - <td class="head-vol">Kernel Developer's Manual</td> - <td class="head-rtitle">SHM_MAP(9)</td> - </tr> -</table> -<div class="manual-text"> -<section class="Sh"> -<h1 class="Sh" id="NAME"><a class="permalink" href="#NAME">NAME</a></h1> -<p class="Pp"><code class="Nm">shm_map</code>, <code class="Nm">shm_unmap</code> - — <span class="Nd">map shared memory objects into the kernel's - address space</span></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> -<p class="Pp"><code class="In">#include - <<a class="In">sys/types.h</a>></code> - <br/> - <code class="In">#include <<a class="In">sys/mman.h</a>></code></p> -<p class="Pp"><var class="Ft">int</var> - <br/> - <code class="Fn">shm_map</code>(<var class="Fa" style="white-space: nowrap;">struct - file *fp</var>, <var class="Fa" style="white-space: nowrap;">size_t - size</var>, <var class="Fa" style="white-space: nowrap;">off_t offset</var>, - <var class="Fa" style="white-space: nowrap;">void **memp</var>);</p> -<p class="Pp"><var class="Ft">int</var> - <br/> - <code class="Fn">shm_unmap</code>(<var class="Fa" style="white-space: nowrap;">struct - file *fp</var>, <var class="Fa" style="white-space: nowrap;">void - *mem</var>, <var class="Fa" style="white-space: nowrap;">size_t - size</var>);</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> -<p class="Pp">The - <a class="permalink" href="#shm_map"><code class="Fn" id="shm_map">shm_map</code></a>() - and <code class="Fn">shm_unmap</code>() functions provide an API for mapping - shared memory objects into the kernel. Shared memory objects are created by - <a class="Xr">shm_open(2)</a>. These objects can then be passed into the - kernel via file descriptors.</p> -<p class="Pp">A shared memory object cannot be shrunk while it is mapped into - the kernel. This is to avoid invalidating any pages that may be wired into - the kernel's address space. Shared memory objects can still be grown while - mapped into the kernel.</p> -<p class="Pp" id="shm_map~2">To simplify the accounting needed to enforce the - above requirement, callers of this API are required to unmap the entire - region mapped by - <a class="permalink" href="#shm_map~2"><code class="Fn">shm_map</code></a>() - when calling <code class="Fn">shm_unmap</code>(). Unmapping only a portion - of the region is not permitted.</p> -<p class="Pp" id="shm_map~3">The - <a class="permalink" href="#shm_map~3"><code class="Fn">shm_map</code></a>() - function locates the shared memory object associated with the open file - <var class="Fa">fp</var>. It maps the region of that object described by - <var class="Fa">offset</var> and <var class="Fa">size</var> into the - kernel's address space. If it succeeds, <var class="Fa">*memp</var> will be - set to the start of the mapping. All pages for the range will be wired into - memory upon successful return.</p> -<p class="Pp" id="shm_unmap">The - <a class="permalink" href="#shm_unmap"><code class="Fn">shm_unmap</code></a>() - function unmaps a region previously mapped by - <code class="Fn">shm_map</code>(). The <var class="Fa">mem</var> argument - should match the value previously returned in <var class="Fa">*memp</var>, - and the <var class="Fa">size</var> argument should match the value passed to - <code class="Fn">shm_map</code>().</p> -<p class="Pp" id="shm_map~4">Note that - <a class="permalink" href="#shm_map~4"><code class="Fn">shm_map</code></a>() - will not hold an extra reference on the open file <var class="Fa">fp</var> - for the lifetime of the mapping. Instead, the calling code is required to do - this if it wishes to use <code class="Fn">shm_unmap</code>() on the region - in the future.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="RETURN_VALUES"><a class="permalink" href="#RETURN_VALUES">RETURN - VALUES</a></h1> -<p class="Pp">The <code class="Fn">shm_map</code>() and - <code class="Fn">shm_unmap</code>() functions return zero on success or an - error on failure.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="EXAMPLES"><a class="permalink" href="#EXAMPLES">EXAMPLES</a></h1> -<p class="Pp">The following function accepts a file descriptor for a shared - memory object. It maps the first sixteen kilobytes of the object into the - kernel, performs some work on that address, and then unmaps the address - before returning.</p> -<div class="Bd Pp Bd-indent Li"> -<pre>int -shm_example(int fd) -{ - struct file *fp; - void *mem; - int error; - - error = fget(curthread, fd, CAP_MMAP, &fp); - if (error) - return (error); - error = shm_map(fp, 16384, 0, &mem); - if (error) { - fdrop(fp, curthread); - return (error); - } - - /* Do something with 'mem'. */ - - error = shm_unmap(fp, mem, 16384); - fdrop(fp, curthread); - return (error); -}</pre> -</div> -</section> -<section class="Sh"> -<h1 class="Sh" id="ERRORS"><a class="permalink" href="#ERRORS">ERRORS</a></h1> -<p class="Pp">The <code class="Fn">shm_map</code>() function returns the - following errors on failure:</p> -<dl class="Bl-tag"> - <dt id="EINVAL">[<a class="permalink" href="#EINVAL"><code class="Er">EINVAL</code></a>]</dt> - <dd>The open file <var class="Fa">fp</var> is not a shared memory object.</dd> - <dt id="EINVAL~2">[<a class="permalink" href="#EINVAL~2"><code class="Er">EINVAL</code></a>]</dt> - <dd>The requested region described by <var class="Fa">offset</var> and - <var class="Fa">size</var> extends beyond the end of the shared memory - object.</dd> - <dt id="ENOMEM">[<a class="permalink" href="#ENOMEM"><code class="Er">ENOMEM</code></a>]</dt> - <dd>Insufficient address space was available.</dd> - <dt id="EACCES">[<a class="permalink" href="#EACCES"><code class="Er">EACCES</code></a>]</dt> - <dd>The shared memory object could not be mapped due to a protection - error.</dd> - <dt id="EINVAL~3">[<a class="permalink" href="#EINVAL~3"><code class="Er">EINVAL</code></a>]</dt> - <dd>The shared memory object could not be mapped due to some other VM - error.</dd> -</dl> -<p class="Pp">The <code class="Fn">shm_unmap</code>() function returns the - following errors on failure:</p> -<dl class="Bl-tag"> - <dt id="EINVAL~4">[<a class="permalink" href="#EINVAL~4"><code class="Er">EINVAL</code></a>]</dt> - <dd>The open file <var class="Fa">fp</var> is not a shared memory object.</dd> - <dt id="EINVAL~5">[<a class="permalink" href="#EINVAL~5"><code class="Er">EINVAL</code></a>]</dt> - <dd>The address range described by <var class="Fa">mem</var> and - <var class="Fa">size</var> is not a valid address range.</dd> - <dt id="EINVAL~6">[<a class="permalink" href="#EINVAL~6"><code class="Er">EINVAL</code></a>]</dt> - <dd>The address range described by <var class="Fa">mem</var> and - <var class="Fa">size</var> is not backed by the shared memory object - associated with the open file <var class="Fa">fp</var>, or the address - range does not cover the entire mapping of the object.</dd> -</dl> -</section> -<section class="Sh"> -<h1 class="Sh" id="SEE_ALSO"><a class="permalink" href="#SEE_ALSO">SEE - ALSO</a></h1> -<p class="Pp"><a class="Xr">shm_open(2)</a></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> -<p class="Pp">This API was first introduced in <span class="Ux">FreeBSD - 10.0</span>.</p> -</section> -</div> -<table class="foot"> - <tr> - <td class="foot-date">December 14, 2011</td> - <td class="foot-os">FreeBSD 15.0</td> - </tr> -</table> |