diff options
Diffstat (limited to 'usr/src/lib/libast/common/disc/sfdcdio.c')
| -rw-r--r-- | usr/src/lib/libast/common/disc/sfdcdio.c | 228 |
1 files changed, 228 insertions, 0 deletions
diff --git a/usr/src/lib/libast/common/disc/sfdcdio.c b/usr/src/lib/libast/common/disc/sfdcdio.c new file mode 100644 index 0000000000..ed7720d229 --- /dev/null +++ b/usr/src/lib/libast/common/disc/sfdcdio.c @@ -0,0 +1,228 @@ +/*********************************************************************** +* * +* This software is part of the ast package * +* Copyright (c) 1985-2007 AT&T Knowledge Ventures * +* and is licensed under the * +* Common Public License, Version 1.0 * +* by AT&T Knowledge Ventures * +* * +* A copy of the License is available at * +* http://www.opensource.org/licenses/cpl1.0.txt * +* (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) * +* * +* Information and Software Systems Research * +* AT&T Research * +* Florham Park NJ * +* * +* Glenn Fowler <gsf@research.att.com> * +* David Korn <dgk@research.att.com> * +* Phong Vo <kpv@research.att.com> * +* * +***********************************************************************/ +#include "sfdchdr.h" + +/* Discipline to turn on direct IO capability. +** This currently only works for XFS on SGI's. +** +** Written by Kiem-Phong Vo, kpv@research.att.com, 03/18/1998. +*/ + +#ifndef FDIRECT +#undef F_FIOINFO +#endif + +typedef struct _direct_s +{ Sfdisc_t disc; /* Sfio discipline */ + int cntl; /* file control flags */ +#ifdef F_DIOINFO + struct dioattr dio; /* direct IO params */ +#endif +} Direct_t; + +/* convert a pointer to an int */ +#define P2I(p) (Sfulong_t)((char*)(p) - (char*)0) + +#if __STD_C +static ssize_t diordwr(Sfio_t* f, Void_t* buf, size_t n, Direct_t* di, int type) +#else +static ssize_t diordwr(f, buf, n, di, type) +Sfio_t* f; +Void_t* buf; +size_t n; +Direct_t* di; +int type; +#endif +{ + size_t rw, done; + ssize_t rv; + + done = 0; /* amount processed by direct IO */ + +#ifdef F_DIOINFO + if((P2I(buf)%di->dio.d_mem) == 0 && + (f->here%di->dio.d_miniosz) == 0 && n >= di->dio.d_miniosz ) + { /* direct IO ok, make sure we're in the right mode */ + if(!(di->cntl & FDIRECT) ) + { di->cntl |= FDIRECT; + (void)fcntl(f->file, F_SETFL, di->cntl); + } + + for(rw = (n/di->dio.d_miniosz)*di->dio.d_miniosz;; ) + { size_t io; + + if((io = rw) > di->dio.d_maxiosz ) + io = di->dio.d_maxiosz; + if(type == SF_READ) + rv = read(f->file,buf,io); + else rv = write(f->file,buf,io); + + if(rv > 0) + { rw -= rv; done += rv; + buf = (Void_t*)((char*)buf + rv); + } + + if(rv < io || rw < di->dio.d_miniosz) + break; + } + } + + if(done < n && (di->cntl & FDIRECT) ) + { /* turn off directIO for remaining IO operation */ + di->cntl &= ~FDIRECT; + (void)fcntl(f->file, F_SETFL, di->cntl); + } +#endif /*F_DIOINFO*/ + + if((rw = n-done) > 0 && + (rv = type == SF_READ ? read(f->file,buf,rw) : write(f->file,buf,rw)) > 0 ) + done += rv; + + return done ? done : rv; +} + +#if __STD_C +static ssize_t dioread(Sfio_t* f, Void_t* buf, size_t n, Sfdisc_t* disc) +#else +static ssize_t dioread(f, buf, n, disc) +Sfio_t* f; +Void_t* buf; +size_t n; +Sfdisc_t* disc; +#endif +{ + return diordwr(f, buf, n, (Direct_t*)disc, SF_READ); +} + +#if __STD_C +static ssize_t diowrite(Sfio_t* f, const Void_t* buf, size_t n, Sfdisc_t* disc) +#else +static ssize_t diowrite(f, buf, n, disc) +Sfio_t* f; +Void_t* buf; +size_t n; +Sfdisc_t* disc; +#endif +{ + return diordwr(f, (Void_t*)buf, n, (Direct_t*)disc, SF_WRITE); +} + +#if __STD_C +static int dioexcept(Sfio_t* f, int type, Void_t* data, Sfdisc_t* disc) +#else +static int dioexcept(f,type,data,disc) +Sfio_t* f; +int type; +Void_t* data; +Sfdisc_t* disc; +#endif +{ + Direct_t* di = (Direct_t*)disc; + + if(type == SF_FINAL || type == SF_DPOP) + { +#ifdef F_DIOINFO + if(di->cntl&FDIRECT) + { di->cntl &= ~FDIRECT; + (void)fcntl(f->file,F_SETFL,di->cntl); + } +#endif + free(disc); + } + + return 0; +} + +#if __STD_C +int sfdcdio(Sfio_t* f, size_t bufsize) +#else +int sfdcdio(f, bufsize) +Sfio_t* f; +size_t bufsize; +#endif +{ +#ifndef F_DIOINFO + return -1; +#else + int cntl; + struct dioattr dio; + Void_t* buf; + Direct_t* di; + + if(f->extent < 0 || (f->flags&SF_STRING)) + return -1; + + if((cntl = fcntl(f->file,F_GETFL,0)) < 0) + return -1; + + if(!(cntl&FDIRECT) ) + { cntl |= FDIRECT; + if(fcntl(f->file,F_SETFL,cntl) < 0) + return -1; + } + + if(fcntl(f->file,F_DIOINFO,&dio) < 0) + goto no_direct; + + if(bufsize > 0) + bufsize = (bufsize/dio.d_miniosz)*dio.d_miniosz; + if(bufsize <= 0) + bufsize = dio.d_miniosz*64; + if(bufsize > dio.d_maxiosz) + bufsize = dio.d_maxiosz; + + if(!(di = (Direct_t*)malloc(sizeof(Direct_t))) ) + goto no_direct; + + if(!(buf = (Void_t*)memalign(dio.d_mem,bufsize)) ) + { free(di); + goto no_direct; + } + + sfsetbuf(f,buf,bufsize); + if(sfsetbuf(f,buf,0) == buf) + sfset(f,SF_MALLOC,1); + else + { free(buf); + free(di); + goto no_direct; + } + + di->disc.readf = dioread; + di->disc.writef = diowrite; + di->disc.seekf = NIL(Sfseek_f); + di->disc.exceptf = dioexcept; + di->cntl = cntl; + di->dio = dio; + + if(sfdisc(f,(Sfdisc_t*)di) != (Sfdisc_t*)di) + { free(di); + no_direct: + cntl &= ~FDIRECT; + (void)fcntl(f->file,F_SETFL,cntl); + return -1; + } + + return 0; + +#endif /*F_DIOINFO*/ +} |