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diff --git a/static/freebsd/man4/mem.4 3.html b/static/freebsd/man4/mem.4 3.html deleted file mode 100644 index eec983b3..00000000 --- a/static/freebsd/man4/mem.4 3.html +++ /dev/null @@ -1,270 +0,0 @@ -<table class="head"> - <tr> - <td class="head-ltitle">MEM(4)</td> - <td class="head-vol">Device Drivers Manual</td> - <td class="head-rtitle">MEM(4)</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">mem</code>, <code class="Nm">kmem</code> — - <span class="Nd">memory files</span></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="SYNOPSIS"><a class="permalink" href="#SYNOPSIS">SYNOPSIS</a></h1> -<p class="Pp"><code class="Cd">device mem</code></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="DESCRIPTION"><a class="permalink" href="#DESCRIPTION">DESCRIPTION</a></h1> -<p class="Pp">The special file <span class="Pa">/dev/mem</span> is an interface - to the physical memory of the computer. Byte offsets in this file are - interpreted as physical memory addresses. Reading and writing this file is - equivalent to reading and writing memory itself. Only offsets within the - bounds of <span class="Pa">/dev/mem</span> are allowed.</p> -<p class="Pp">Kernel virtual memory is accessed through the interface - <span class="Pa">/dev/kmem</span> in the same manner as - <span class="Pa">/dev/mem</span>. Only kernel virtual addresses that are - currently mapped to memory are allowed.</p> -<p class="Pp">On ISA the I/O memory space begins at physical address 0x000a0000 - and runs to 0x00100000. The per-process data size for the current process is - <code class="Dv">UPAGES</code> long, and ends at virtual address - 0xf0000000.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="IOCTL_INTERFACE"><a class="permalink" href="#IOCTL_INTERFACE">IOCTL - INTERFACE</a></h1> -<section class="Ss"> -<h2 class="Ss" id="Address_Properties"><a class="permalink" href="#Address_Properties">Address - Properties</a></h2> -<p class="Pp">The <code class="Dv">MEM_EXTRACT_PADDR</code> ioctl can be used to - look up the physical address and NUMA domain of a given virtual address in - the calling process' address space. The request is described by</p> -<div class="Bd Pp Li"> -<pre>struct mem_extract { - uint64_t me_vaddr; /* input */ - uint64_t me_paddr; /* output */ - int me_domain; /* output */ - int me_state; /* output */ -};</pre> -</div> -<p class="Pp">The ioctl returns an error if the address is not valid. The - information returned by <code class="Dv">MEM_EXTRACT_PADDR</code> may be out - of date by the time that the ioctl call returns. Specifically, concurrent - system calls, page faults, or system page reclamation activity may have - unmapped the virtual page or replaced the backing physical page before the - ioctl call returns. Wired pages, e.g., those locked by - <a class="Xr">mlock(2)</a>, will not be reclaimed by the system.</p> -<p class="Pp">The <var class="Fa">me_state</var> field provides information - about the state of the virtual page:</p> -<dl class="Bl-tag"> - <dt id="ME_STATE_INVALID"><a class="permalink" href="#ME_STATE_INVALID"><code class="Dv">ME_STATE_INVALID</code></a></dt> - <dd>The virtual address is invalid.</dd> - <dt id="ME_STATE_VALID"><a class="permalink" href="#ME_STATE_VALID"><code class="Dv">ME_STATE_VALID</code></a></dt> - <dd>The virtual address is valid but is not mapped at the time of the ioctl - call.</dd> - <dt id="ME_STATE_MAPPED"><a class="permalink" href="#ME_STATE_MAPPED"><code class="Dv">ME_STATE_MAPPED</code></a></dt> - <dd>The virtual address corresponds to a physical page mapping, and the - <var class="Fa">me_paddr</var> and <var class="Fa">me_domain</var> fields - are valid.</dd> -</dl> -</section> -<section class="Ss"> -<h2 class="Ss" id="Memory_Ranges"><a class="permalink" href="#Memory_Ranges">Memory - Ranges</a></h2> -<p class="Pp">Several architectures allow attributes to be associated with - ranges of physical memory. These attributes can be manipulated via - <a class="permalink" href="#ioctl"><code class="Fn" id="ioctl">ioctl</code></a>() - calls performed on <span class="Pa">/dev/mem</span>. Declarations and data - types are to be found in - <code class="In"><<a class="In">sys/memrange.h</a>></code>.</p> -<p class="Pp">The specific attributes, and number of programmable ranges may - vary between architectures. The full set of supported attributes is:</p> -<dl class="Bl-tag"> - <dt id="MDF_UNCACHEABLE"><a class="permalink" href="#MDF_UNCACHEABLE"><code class="Dv">MDF_UNCACHEABLE</code></a></dt> - <dd>The region is not cached.</dd> - <dt id="MDF_WRITECOMBINE"><a class="permalink" href="#MDF_WRITECOMBINE"><code class="Dv">MDF_WRITECOMBINE</code></a></dt> - <dd>Writes to the region may be combined or performed out of order.</dd> - <dt id="MDF_WRITETHROUGH"><a class="permalink" href="#MDF_WRITETHROUGH"><code class="Dv">MDF_WRITETHROUGH</code></a></dt> - <dd>Writes to the region are committed synchronously.</dd> - <dt id="MDF_WRITEBACK"><a class="permalink" href="#MDF_WRITEBACK"><code class="Dv">MDF_WRITEBACK</code></a></dt> - <dd>Writes to the region are committed asynchronously.</dd> - <dt id="MDF_WRITEPROTECT"><a class="permalink" href="#MDF_WRITEPROTECT"><code class="Dv">MDF_WRITEPROTECT</code></a></dt> - <dd>The region cannot be written to.</dd> -</dl> -<p class="Pp">Memory ranges are described by</p> -<div class="Bd Pp Li"> -<pre>struct mem_range_desc { - uint64_t mr_base; /* physical base address */ - uint64_t mr_len; /* physical length of region */ - int mr_flags; /* attributes of region */ - char mr_owner[8]; -};</pre> -</div> -<p class="Pp">In addition to the region attributes listed above, the following - flags may also be set in the <var class="Fa">mr_flags</var> field:</p> -<dl class="Bl-tag"> - <dt>MDF_FIXBASE</dt> - <dd>The region's base address cannot be changed.</dd> - <dt>MDF_FIXLEN</dt> - <dd>The region's length cannot be changed.</dd> - <dt>MDF_FIRMWARE</dt> - <dd>The region is believed to have been established by the system - firmware.</dd> - <dt>MDF_ACTIVE</dt> - <dd>The region is currently active.</dd> - <dt>MDF_BOGUS</dt> - <dd>We believe the region to be invalid or otherwise erroneous.</dd> - <dt>MDF_FIXACTIVE</dt> - <dd>The region cannot be disabled.</dd> - <dt>MDF_BUSY</dt> - <dd>The region is currently owned by another process and may not be - altered.</dd> -</dl> -<p class="Pp">Operations are performed using</p> -<div class="Bd Pp Li"> -<pre>struct mem_range_op { - struct mem_range_desc *mo_desc; - int mo_arg[2]; -};</pre> -</div> -<p class="Pp">The <code class="Dv">MEMRANGE_GET</code> ioctl is used to retrieve - current memory range attributes. If <var class="Va">mo_arg[0]</var> is set - to 0, it will be updated with the total number of memory range descriptors. - If greater than 0, the array at <var class="Va">mo_desc</var> will be filled - with a corresponding number of descriptor structures, or the maximum, - whichever is less.</p> -<p class="Pp">The <code class="Dv">MEMRANGE_SET</code> ioctl is used to add, - alter and remove memory range attributes. A range with the - <code class="Dv">MDF_FIXACTIVE</code> flag may not be removed; a range with - the <code class="Dv">MDF_BUSY</code> flag may not be removed or updated.</p> -<p class="Pp"><var class="Va">mo_arg[0]</var> should be set to - <code class="Dv">MEMRANGE_SET_UPDATE</code> to update an existing or - establish a new range, or to <code class="Dv">MEMRANGE_SET_REMOVE</code> to - remove a range.</p> -</section> -<section class="Ss"> -<h2 class="Ss" id="Live_Kernel_Dumps"><a class="permalink" href="#Live_Kernel_Dumps">Live - Kernel Dumps</a></h2> -<p class="Pp">The <code class="Dv">MEM_KERNELDUMP</code> ioctl will initiate a - kernel dump against the running system, the contents of which will be - written to a process-owned file descriptor. The resulting dump output will - be in minidump format. The request is described by</p> -<div class="Bd Pp Li"> -<pre>struct mem_livedump_arg { - int fd; /* input */ - int flags /* input */ - uint8_t compression /* input */ -};</pre> -</div> -<p class="Pp">The <var class="Va">fd</var> field is used to pass the file - descriptor.</p> -<p class="Pp">The <var class="Va">flags</var> field is currently unused and must - be set to zero.</p> -<p class="Pp">The <var class="Va">compression</var> field can be used to specify - the desired compression to be applied to the dump output. The supported - values are defined in - <code class="In"><<a class="In">sys/kerneldump.h</a>></code>; that is, - <code class="Dv">KERNELDUMP_COMP_NONE</code>, - <code class="Dv">KERNELDUMP_COMP_GZIP</code>, or - <code class="Dv">KERNELDUMP_COMP_ZSTD</code>.</p> -<p class="Pp">Kernel dumps taken against the running system may have - inconsistent kernel data structures due to allocation, deallocation, or - modification of memory concurrent to the dump procedure. Thus, the resulting - core dump is not guaranteed to be usable. A system under load is more likely - to produce an inconsistent result. Despite this, live kernel dumps can be - useful for offline debugging of certain types of kernel bugs, such as - deadlocks, or in inspecting a particular part of the system's state.</p> -</section> -</section> -<section class="Sh"> -<h1 class="Sh" id="RETURN_VALUES"><a class="permalink" href="#RETURN_VALUES">RETURN - VALUES</a></h1> -<section class="Ss"> -<h2 class="Ss" id="MEM_EXTRACT_PADDR"><a class="permalink" href="#MEM_EXTRACT_PADDR">MEM_EXTRACT_PADDR</a></h2> -<p class="Pp">The <code class="Dv">MEM_EXTRACT_PADDR</code> ioctl always returns - a value of zero.</p> -</section> -<section class="Ss"> -<h2 class="Ss" id="MEMRANGE_GET/MEMRANGE_SET"><a class="permalink" href="#MEMRANGE_GET/MEMRANGE_SET">MEMRANGE_GET/MEMRANGE_SET</a></h2> -<dl class="Bl-tag"> - <dt>[<code class="Er">EOPNOTSUPP</code>]</dt> - <dd>Memory range operations are not supported on this architecture.</dd> - <dt>[<code class="Er">ENXIO</code>]</dt> - <dd>No memory range descriptors are available (e.g., firmware has not enabled - any).</dd> - <dt>[<code class="Er">EINVAL</code>]</dt> - <dd>The memory range supplied as an argument is invalid or overlaps another - range in a fashion not supported by this architecture.</dd> - <dt>[<code class="Er">EBUSY</code>]</dt> - <dd>An attempt to remove or update a range failed because the range is - busy.</dd> - <dt>[<code class="Er">ENOSPC</code>]</dt> - <dd>An attempt to create a new range failed due to a shortage of hardware - resources (e.g., descriptor slots).</dd> - <dt>[<code class="Er">ENOENT</code>]</dt> - <dd>An attempt to remove a range failed because no range matches the - descriptor base/length supplied.</dd> - <dt>[<code class="Er">EPERM</code>]</dt> - <dd>An attempt to remove a range failed because the range is permanently - enabled.</dd> -</dl> -</section> -<section class="Ss"> -<h2 class="Ss" id="MEM_KERNELDUMP"><a class="permalink" href="#MEM_KERNELDUMP">MEM_KERNELDUMP</a></h2> -<dl class="Bl-tag"> - <dt>[<code class="Er">EOPNOTSUPP</code>]</dt> - <dd>Kernel minidumps are not supported on this architecture.</dd> - <dt>[<code class="Er">EPERM</code>]</dt> - <dd>An attempt to begin the kernel dump failed because the calling thread - lacks the</dd> - <dt>[<code class="Er">EBADF</code>]</dt> - <dd>The supplied file descriptor was invalid, or does not have write - permission.</dd> - <dt>[<code class="Er">EBUSY</code>]</dt> - <dd>An attempt to begin the kernel dump failed because one is already in - progress.</dd> - <dt>[<code class="Er">EINVAL</code>]</dt> - <dd>An invalid or unsupported value was specified in - <var class="Va">flags</var>.</dd> - <dt>[<code class="Er">EINVAL</code>]</dt> - <dd>An invalid or unsupported compression type was specified. - <code class="Dv">PRIV_KMEM_READ</code> privilege.</dd> -</dl> -</section> -</section> -<section class="Sh"> -<h1 class="Sh" id="FILES"><a class="permalink" href="#FILES">FILES</a></h1> -<dl class="Bl-tag Bl-compact"> - <dt><span class="Pa">/dev/mem</span></dt> - <dd style="width: auto;"> </dd> - <dt><span class="Pa">/dev/kmem</span></dt> - <dd style="width: auto;"> </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">kvm(3)</a>, <a class="Xr">memcontrol(8)</a></p> -</section> -<section class="Sh"> -<h1 class="Sh" id="HISTORY"><a class="permalink" href="#HISTORY">HISTORY</a></h1> -<p class="Pp">The <span class="Pa">/dev/mem</span> file appeared in - <span class="Ux">Version 1 AT&T UNIX</span> and - <span class="Pa">/dev/kmem</span> in <span class="Ux">Version 5 - AT&T UNIX</span>. The ioctl interface for memory range attributes was - added in <span class="Ux">FreeBSD 3.2</span>.</p> -</section> -<section class="Sh"> -<h1 class="Sh" id="BUGS"><a class="permalink" href="#BUGS">BUGS</a></h1> -<p class="Pp">Busy range attributes are not yet managed correctly.</p> -<p class="Pp">This device is required for all users of <a class="Xr">kvm(3)</a> - to operate.</p> -</section> -</div> -<table class="foot"> - <tr> - <td class="foot-date">March 24, 2024</td> - <td class="foot-os">FreeBSD 15.0</td> - </tr> -</table> |