Date: Thu, 31 Jan 2002 15:40:02 -0800 (PST) From: Hiten Pandya <hiten@uk.FreeBSD.org> To: freebsd-doc@freebsd.org Subject: re: docs/30603 [PATCH] Message-ID: <200201312340.g0VNe2L47896@freefall.freebsd.org>
next in thread | raw e-mail | index | archive | help
The following reply was made to PR docs/30603; it has been noted by GNATS. From: Hiten Pandya <hiten@uk.FreeBSD.org> To: bug-followup@FreeBSD.org Cc: phk@FreeBSD.org Subject: re: docs/30603 [PATCH] Date: Thu, 31 Jan 2002 23:35:30 +0000 I finally got time to fix this problem, and make a patch to the physio(9) man page. Well, hear it is. I think this should do. I have made all the neccessary changes, as well as add a HISTORY section. A copy of this diff is also available at: http://www.pittgoth.com/~hiten/diffs/physio.9.diff If there is any problems with this diff, please do not hesitate to contact me. Feedback is also very much appreciated. Regards, - Hiten - <hiten@uk.FreeBSD.org> --- physio.9 Wed Dec 26 23:14:04 2001 +++ physio.9.new Wed Jan 30 06:45:02 2002 @@ -54,16 +54,12 @@ .Fn physio is a helper function typically called from character device read and write routines to start I/O on a user process buffer. -It calls back on the -provided -.Fa strategy -routine one or more times to complete the transfer described by -.Fa uio . -The maximum amount of data to transfer with each call to -.Fa strategy -is determined by the -.Fa minphys -routine. +The maximum amount of data to transfer with each call +is determined by: +.Bd -literal +dev->si_iosize_max +.Ed +.Pp Since .Fa uio normally describes user space addresses, @@ -74,38 +70,11 @@ .Fn physio always awaits the completion of the entire requested transfer before returning, unless an error condition is detected earlier. -In all cases, -the buffer passed in -.Fa bp -is locked (marked as -.Dq busy ) -for the duration of the entire transfer. .Pp A break-down of the arguments follows: .Bl -tag -width indent -.It Fa strategy -The device strategy routine to call for each chunk of data to initiate -device I/O. -.It Fa bp -The buffer to use with the strategy routine. -The buffer flags will have -.Dv B_BUSY , -and -.Dv B_PHYS -set when passed to the strategy routine. -If -.Dv NULL , -a buffer is allocated from a system pool. .It Fa dev The device number identifying the device to interact with. -.It Fa flags -Direction of transfer; the only valid settings are -.Dv B_READ -or -.Dv B_WRITE . -.It Fa minphys -A device specific routine called to determine the maximum transfer size -that the device's strategy routine can handle. .It Fa uio The description of the entire transfer as requested by the user process. Currently, the results of passing a @@ -139,3 +108,11 @@ .Sh SEE ALSO .Xr read 2 , .Xr write 2 +.Sh HISTORY +The +.Xr physio 9 +manual page is originally from NetBSD with minor changes for applicability +with FreeBSD. +.Pp +The physio(9) call has been completely re-written for providing higher +I/O performance, and better paging performance. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-doc" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?200201312340.g0VNe2L47896>