diff options
author | imp <imp@FreeBSD.org> | 2004-07-10 01:10:17 +0000 |
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committer | imp <imp@FreeBSD.org> | 2004-07-10 01:10:17 +0000 |
commit | 10c37ef567a96811a59fb7740997f36fbb45a143 (patch) | |
tree | 8ba15e159ee486788275fab0dad253e2bf86eb3f /share/man | |
parent | 8526267db84218fbc82e517c5ae4cc9e986b11b8 (diff) | |
download | FreeBSD-src-10c37ef567a96811a59fb7740997f36fbb45a143.zip FreeBSD-src-10c37ef567a96811a59fb7740997f36fbb45a143.tar.gz |
Modernize description of physio. Make explicit that this creates a
request that's passed to the driver's strategy.
Diffstat (limited to 'share/man')
-rw-r--r-- | share/man/man9/physio.9 | 24 |
1 files changed, 19 insertions, 5 deletions
diff --git a/share/man/man9/physio.9 b/share/man/man9/physio.9 index d519d63..1906d8e 100644 --- a/share/man/man9/physio.9 +++ b/share/man/man9/physio.9 @@ -36,7 +36,7 @@ .\" .\" $FreeBSD$ .\" -.Dd June 15, 1996 +.Dd July 8, 2004 .Dt PHYSIO 9 .Os .Sh NAME @@ -60,15 +60,22 @@ routines to start I/O on a user process buffer. The maximum amount of data to transfer with each call is determined by .Fa dev->si_iosize_max . +The +.Fn physio +call converts the I/O request into a +.Fn strategy +request and passes the new request to the driver's +.Fn strategy +routine for processing. .Pp Since .Fa uio normally describes user space addresses, .Fn physio -needs to lock the process into memory. -This is done by setting the -.Dv P_PHYSIO -flag on the process. +needs to lock the those pages into memory. +This is done by calling +.Fn vmapbuf +for the appropriate pages. .Fn physio always awaits the completion of the entire requested transfer before returning, unless an error condition is detected earlier. @@ -86,6 +93,13 @@ structure with the set to anything other than .Dv UIO_USERSPACE are undefined. +.It Fa ioflag +The ioflag argument from the +.Fn read +or +.Fn write +function calling +.Fn physio . .El .Sh RETURN VALUES If successful |