diff options
| author | Jacob McDonnell <jacob@jacobmcdonnell.com> | 2026-04-25 16:08:12 -0400 |
|---|---|---|
| committer | Jacob McDonnell <jacob@jacobmcdonnell.com> | 2026-04-25 16:08:12 -0400 |
| commit | b9cde963555b6519c5dbd34a39dee3418f593437 (patch) | |
| tree | 453accad3c3286e3416d4160de4a87223aff684c /static/freebsd/man9/vm_page_bits.9 | |
| parent | 5cb84ec742fd33f78c8022863fadaa8d0d93e176 (diff) | |
feat: Added FreeBSD man pages
Diffstat (limited to 'static/freebsd/man9/vm_page_bits.9')
| -rw-r--r-- | static/freebsd/man9/vm_page_bits.9 | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/static/freebsd/man9/vm_page_bits.9 b/static/freebsd/man9/vm_page_bits.9 new file mode 100644 index 00000000..c8900f4a --- /dev/null +++ b/static/freebsd/man9/vm_page_bits.9 @@ -0,0 +1,165 @@ +.\" +.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice(s), this list of conditions and the following disclaimer as +.\" the first lines of this file unmodified other than the possible +.\" addition of one or more copyright notices. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice(s), this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY +.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED +.\" WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE +.\" DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE LIABLE FOR ANY +.\" DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES +.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR +.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +.\" CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH +.\" DAMAGE. +.\" +.Dd December 1, 2001 +.Dt VM_PAGE_BITS 9 +.Os +.Sh NAME +.Nm vm_page_bits , +.Nm vm_page_set_validclean , +.Nm vm_page_clear_dirty , +.Nm vm_page_set_invalid , +.Nm vm_page_zero_invalid , +.Nm vm_page_is_valid , +.Nm vm_page_test_dirty , +.Nm vm_page_dirty , +.Nm vm_page_undirty +.Nd "manage page clean and dirty bits" +.Sh SYNOPSIS +.In sys/param.h +.In vm/vm.h +.In vm/vm_page.h +.Ft int +.Fn vm_page_bits "int base" "int size" +.Ft void +.Fn vm_page_set_validclean "vm_page_t m" "int base" "int size" +.Ft void +.Fn vm_page_clear_dirty "vm_page_t m" "int base" "int size" +.Ft void +.Fn vm_page_set_invalid "vm_page_t m" "int base" "int size" +.Ft void +.Fn vm_page_zero_invalid "vm_page_t m" "boolean_t setvalid" +.Ft int +.Fn vm_page_is_valid "vm_page_t m" "int base" "int size" +.Ft void +.Fn vm_page_test_dirty "vm_page_t m" +.Ft void +.Fn vm_page_dirty "vm_page_t m" +.Ft void +.Fn vm_page_undirty "vm_page_t m" +.Sh DESCRIPTION +.Fn vm_page_bits +calculates the bits representing the +.Dv DEV_BSIZE +range of bytes between +.Fa base +and +.Fa size . +The byte range is expected to be within a single page, and if +.Fa size +is zero, no bits will be set. +.Pp +.Fn vm_page_set_validclean +flags the byte range between +.Fa base +and +.Fa size +as valid and clean. +The range is expected to be +.Dv DEV_BSIZE +aligned and no larger than +.Dv PAGE_SIZE . +If it is not properly aligned, any unaligned chunks of the +.Dv DEV_BSIZE +blocks at the beginning and end of the range will be zeroed. +.Pp +If +.Fa base +is zero and +.Fa size +is one page, the modified bit in the page map is cleared; as well, +the +.Dv VPO_NOSYNC +flag is cleared. +.Pp +.Fn vm_page_clear_dirty +clears the dirty bits within a page in the range between +.Fa base +and +.Fa size . +The bits representing the range are calculated by calling +.Fn vm_page_bits . +.Pp +.Fn vm_page_set_invalid +clears the bits in both the valid and dirty flags representing +the +.Dv DEV_BSIZE +blocks between +.Fa base +and +.Fa size +in the page. +The bits are calculated by calling +.Fn vm_page_bits . +As well as clearing the bits within the page, the generation +number within the object holding the page is incremented. +.Pp +.Fn vm_page_zero_invalid +zeroes all of the blocks within the page that are currently +flagged as invalid. +If +.Fa setvalid +is +.Dv TRUE , +all of the valid bits within the page are set. +.Pp +In some cases, such as NFS, the valid bits cannot be set +in order to maintain cache consistency. +.Pp +.Fn vm_page_is_valid +checks to determine if the all of the +.Dv DEV_BSIZE +blocks between +.Fa base +and +.Fa size +of the page are valid. +If +.Fa size +is zero and the page is entirely invalid +.Fn vm_page_is_valid +will return +.Dv TRUE , +in all other cases a size of zero will return +.Dv FALSE . +.Pp +.Fn vm_page_test_dirty +checks if a page has been modified via any of its physical maps, +and if so, flags the entire page as dirty. +.Fn vm_page_dirty +is called to modify the dirty bits. +.Pp +.Fn vm_page_dirty +flags the entire page as dirty. +It is expected that the page is not currently on the cache queue. +.Pp +.Fn vm_page_undirty +clears all of the dirty bits in a page. +.Sh NOTES +None of these functions are allowed to block. +.Sh AUTHORS +This manual page was written by +.An Chad David Aq Mt davidc@acns.ab.ca . |
