Fix font issues
Submitted by: heirloom doctools upstream
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Notes:
svn2git
2020-12-20 02:59:44 +00:00
svn path=/head/; revision=282297
@ -40,7 +40,7 @@ This paper contains the road-map for a stackable "BIO" system in
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FreeBSD, which will support these facilities.
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.AE
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.NH
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The miseducation of \fCstruct buf\fP.
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The miseducation of \f(CW.)struct buf\fP.
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.PP
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To fully appreciate the topic, I include a little historic overview
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of struct buf, it is a most enlightening case of not exactly bit-rot
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@ -51,7 +51,7 @@ memory is was introduced into UNIX, all disk I/O were done from or
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to a struct buf. In the 6th edition sources, as printed in Lions
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Book, struct buf looks like this:
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.DS
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.ft C
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.ft CW
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.ps -1
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struct buf
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{
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@ -95,7 +95,7 @@ aspect and only a few fields relate exclusively to the cache aspect.
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If we step forward to the BSD 4.4-Lite-2 release, struct buf has grown
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a bit here or there:
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.DS
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.ft C
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.ft CW
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.ps -1
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struct buf {
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LIST_ENTRY(buf) b_hash; /* Hash chain. */
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@ -144,7 +144,7 @@ aspect, link buffers to the VM system, provide hacks for file-systems
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.PP
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By the time we get to FreeBSD 3.0 more stuff has grown on struct buf:
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.DS
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.ft C
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.ft CW
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.ps -1
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struct buf {
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LIST_ENTRY(buf) b_hash; /* Hash chain. */
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@ -215,7 +215,7 @@ and Vinum. They all basically do the same: they map I/O requests from
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a logical space to a physical space, and the mappings they perform
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can be 1:1 or 1:N. \**
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.FS
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It is interesting to note that Lions in his comments to the \fCrkaddr\fP
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It is interesting to note that Lions in his comments to the \f(CW.)rkaddr\fP
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routine (p. 16-2) writes \fIThe code in this procedure incorporates
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a special feature for files which extend over more than one disk
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drive. This feature is described in the UPM Section "RK(IV)". Its
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@ -258,7 +258,7 @@ limited extent diskslice/label, which
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need only the I/O aspect, not the vnode, caching or VM linkage.
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.IP
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.I
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The I/O aspect of struct buf should be put in a separate \fCstruct bio\fP.
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The I/O aspect of struct buf should be put in a separate \f(CW.)struct bio\fP.
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.R
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.NH 1
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Implications for future struct buf improvements
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@ -296,7 +296,7 @@ Anything that could be added to or done with
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the I/O aspect of struct buf can also be added to or done
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with the I/O aspect if it lives in a new "struct bio".
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.NH 1
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Implementing a \fCstruct bio\fP
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Implementing a \f(CW.)struct bio\fP
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.PP
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The first decision to be made was who got to use the name "struct buf",
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and considering the fact that it is the I/O aspect which gets separated
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@ -344,7 +344,7 @@ Definition of struct bio
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.PP
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With the cleanup of b_flags in place, the definition of struct bio looks like this:
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.DS
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.ft C
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.ft CW
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.ps -1
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struct bio {
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u_int bio_cmd; /* I/O operation. */
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@ -375,7 +375,7 @@ Definition of struct buf
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After adding a struct bio to struct buf and the fields aliased into it
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struct buf looks like this:
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.DS
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.ft C
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.ft CW
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.ps -1
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struct buf {
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/* XXX: b_io must be the first element of struct buf for now /phk */
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@ -424,7 +424,7 @@ And can be found at http://phk.freebsd.dk/misc
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.FE
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and consists mainly of systematic substitutions like these
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.DS
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.ft C
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.ft CW
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s/struct buf/struct bio/
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s/b_flags/bio_flags/
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s/b_bcount/bio_bcount/
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