
FS cleanup.

Add utility routines bzero, readsb so that balloc, bfree fit on one page.
Make balloc loop clearer.

bowlofstew/sv6,MrHohn/cs518hw3,shining-yang/xv6,penguiner/xv6,preshshah/xv6,firstblade/xv6,ManaPoustizadeh/OS-finalProject,MrHohn/CS-OperatingSystem-hw3,SanchayanMaity/xv6-cs450,liadgi/os163,aclements/sv6,nullpo-head/xv6-mips,ZheyuJin/xv6_reading,ThomasDq/xv6OS,wenhuizhang/xv6-public,shadowfax-ring/mit-xv6,meilank/CS416-hw2,liadgi/os163,TheMatrixShibe/tmsv6,ZheyuJin/xv6_reading,bowlofstew/sv6,rafamanzo/ep4-so,arcbbb/xv6,howerj/xv6,run/xv6,lolosssss/Xv6,KushOza/hw2,OrangeTide/xv6-public,GautamV/xv6,Cheukyin/xv6,robertpd/xv6,expertsnipo/xv6,danrods/xv6Hacks,justodiaz/xv6,chyka-dev/xv6-public,arianvp/xv6,film42/xv6,s-rah/xv6-permissions,firstblade/xv6,shadowfax-ring/mit-xv6,yubai/ksm_xv6,dswann5/os_assignment_3,rafamanzo/ep2-so-xv6,UIKit0/Xv6,vicionator/XV6,sdharan/xv6-rcu,KushOza/hw2,rajma996/xv6,arajago6/Axv6_One,johnson-li/xv6-homework,gnosis23/xv6,wangxiayang/xv6,kingsizeme/xv6,humphreyja/Xv6,raman162/CS450,bngabonziza/xv6,aquamme/xv6,pablogventura/xv6-public,louisje/xv6,Mifnight/xv6-public,BMJHayward/xv6-public,pekopeko1/xv6,HawxChen/Offical-Version-xv6,lord021/Assignment1,logangorence/xv6-public,HugoTian/xv6,konyavic/xv6,Y-liulian/xv6-public,vicionator/XV6,PINK-FL0YD/xv6-public,lorenzo-stoakes/haxv6,HugoTian/xv6,guilleiguaran/xv6,leenjewel/xv6_learn,eewayhsu/xv6,eewayhsu/xv6,svdamani/xv6,wkatsak/xv6,kongming92/6828-xv6,kongming92/6828-xv6,Cheukyin/xv6,maxymania/open-xv6,tehgeekmeister/xv6,rlok3000/xv6,firstblade/xv6,gnosis23/xv6,bngabonziza/xv6,gzpan123/xv6,voytovichs/xv6-public,Royvaknin29/OS_Ass1,UIKit0/Xv6,CHRISTOPHERDIEHL/xv6,v1ta/xv6,nwolovick/xv6-public,WeiranFang/cs518hw3,DuskDragon/xv6,williamsandrew/xv6,danrods/xv6Hacks,ckkashyap/xv6,codelabs-ch/xv6-muen,sigma-random/xv6,prashantkhurana/OS,bngabonziza/xv6-1,ShakhMoves/Shakh6,Mifnight/xv6-public,f13mash/xv6,lord021/Assignment1,aclements/sv6,jsommers/xv6-public,KushOza/hw2,MatanGilead/myxv6,yubai/ksm_xv6,lord021/Assignment2,walafc0/xv6,svdamani/xv6,avana002/xv6,raman162/CS450,laisborin/RT-xv6,GautamV/xv6,gnudeep/xv6,ihciah/XV6-OS,phf/xv6-public,MatanGilead/myxv6,howerj/xv6,ManaPoustizadeh/OS-finalProject,walafc0/xv6,wenhuizhang/xv6-public,AndreiRO/xv6,roygoldman/xv6-fsprot,maxymania/open-xv6,dswann5/os_assignment_3,TheMatrixShibe/tmsv6,tehgeekmeister/xv6,reutz19/xv6_ass4,wenhuizhang/xv6-public,rlok3000/xv6,AndreiRO/xv6,MrHohn/CS-OperatingSystem-hw2,SajadAzami/xv6-pm,laisborin/RT-xv6,ihciah/XV6-OS,nwf/xv6-public,bngabonziza/xv6-public,lolosssss/Xv6,expertsnipo/xv6,jsommers/xv6-public,tamlok/xv6,voytovichs/xv6-public,tamlok/xv6,CKost/Authorization,shtyd/xv6-lua,eewayhsu/xv6,TheMatrixShibe/tmsv6,s-rah/xv6-permissions,sometimesfood/xv6,justodiaz/xv6,f13mash/xv6,bohaoist/xv6,varunk08/xv6,bowlofstew/xv6-public,jsommers/xv6-public,rajma996/xv6,lenw/xv6-public,chrisdew/xv6,liyinhgqw/xv6,MrHohn/cs518hw3,lord021/Assignment2,lenw/xv6-public,jgome043/tearos,ahorn/xv6,jgome043/tearos,arajago6/Axv6_One,humphreyja/Xv6,dswann5/os_assignment_3,varunk08/xv6,MrHohn/cs518hw2,jsommers/xv6-public,ShakhMoves/Shakh6,lishuwnc/Xv6,arianvp/xv6,liorderei/OS_Class,guilleiguaran/xv6,arianvp/xv6,ZheyuJin/xv6_reading,shyandsy/xv6,expertsnipo/xv6,johnson-li/xv6-homework,DuskDragon/xv6,johnson-li/xv6-homework,supr/Xv6,sometimesfood/xv6-public,oskarth/xv6,rafamanzo/ep2-so-xv6,ihciah/xv6,yum185/assign1_partA,CKost/Authorization,run/xv6,lorenzo-stoakes/haxv6,AskDrCatcher/xv6,gzpan123/xv6,gnudeep/xv6,bngabonziza/xv6-1,rajma996/xv6,Y-liulian/xv6-public,meilank/CS416-hw1,humphreyja/Xv6,bngabonziza/xv6-public,konyavic/xv6,MrHohn/CS-OperatingSystem-hw2,gnudeep/xv6,bngabonziza/xv6-1,bngabonziza/xv6-public,chnpmy/xv6,xujunhai1991/xv6,CKost/Authorization,MrHohn/cs518hw3,nwf/xv6-public,kongming92/6828-xv6,robertpd/xv6,TheMatrixShibe/tmsv6,CHRISTOPHERDIEHL/xv6,oskarth/xv6,sdimitro/xv6,5kg/xv6,ThomasDq/xv6OS,jmatth/xv6,wkatsak/xv6,tenstep/xv6,alex0906093/xv6,rlok3000/xv6,lorenzo-stoakes/haxv6,arturosevilla/xv6-turi,prashantkhurana/OS,sometimesfood/xv6,aclements/sv6,shining-yang/xv6,galbenor/os162-4,supdizh/clean_xv6,nwolovick/xv6-public,kazunobu-fujii/xv6,jeffallen/xv6,tamlok/xv6,jeffallen/xv6,nwf/xv6-public,film42/xv6,danluu/Xv6,lorenzo-stoakes/haxv6,nomadium/xv6,roygoldman/xv6-sem,preshshah/xv6,shining-yang/xv6,orenherman/xv6-clone,alex0906093/xv6,arcbbb/xv6,lenw/xv6-public,shadowfax-ring/mit-xv6,nullpo-head/xv6-mips,konyavic/xv6,rajma996/xv6,baboofei/v6rt,shtyd/xv6-lua,romanzhg/xv6,v1ta/xv6,lord021/Assignment2,PINK-FL0YD/xv6-public,supr/Xv6,Y-liulian/xv6-public,danrods/xv6Hacks,i/xv6,siddharthv/xv6,MrHohn/cs518hw3,chrisdew/xv6,Laaia/RT-xv6,khalily/xv6,liorderei/OS_Class,Laaia/RT-xv6,gco/xv6,ihciah/xv6,msyksphinz/xv6-mips,emaadmanzoor/xv6,jgome043/tearos,RicardoParizotto/xv6---stride-scheduling,imagine4077/xv6-public,DuskDragon/xv6,bngabonziza/xv6-1,cpehle/xv6,bngabonziza/xv6,bohaoist/xv6,wasabiz/xv6,niral28/hw1,garzon/xv6-public,MrHohn/CS-OperatingSystem-hw3,siddharthv/xv6,roygoldman/xv6-fsprot,Laaia/RT-xv6,BMJHayward/xv6-public,panks/Xv6,orenherman/xv6-clone,Cheukyin/xv6,sdimitro/xv6,chyka-dev/xv6-public,voytovichs/xv6-public,leenjewel/xv6_learn,nullpo-head/xv6-mips,CHRISTOPHERDIEHL/xv6,AndreiRO/xv6,bohaoist/xv6,Raysmond/xv6,expertsnipo/xv6,gnosis23/xv6,gco/xv6,xv6-jp/xv6,MatanGilead/myxv6,sometimesfood/xv6,AZQ1994/xv6,HawxChen/Offical-Version-xv6,tinti/xv6-ubuntu,sometimesfood/xv6-public,Mifnight/xv6-public,ThomasDq/xv6OS,leenjewel/xv6_learn,SanchayanMaity/xv6-cs450,lishuwnc/Xv6,yum185/assign1_partA,pekopeko1/xv6-code,leenjewel/xv6_learn,svdamani/xv6,ShakhMoves/Shakh6,yum185/assign1_partA,shadowfax-ring/mit-xv6,alex0906093/xv6,PINK-FL0YD/xv6-public,SarthakCodes/xv6,seckcoder/mirror-xv6,pekopeko1/xv6-code,descent/xv6,yum185/assign1_partA,louisje/xv6,Royvaknin29/OS_Ass1,RicardoParizotto/xv6---stride-scheduling,msyksphinz/xv6-mips,CKost/Authorization,lord021/Assignment1,sigma-random/xv6,SanchayanMaity/xv6-cs450,SanchayanMaity/xv6-cs450,tamlok/xv6,RicardoParizotto/xv6---stride-scheduling,logangorence/xv6-public,nullpo-head/xv6-mips,SarthakCodes/xv6,arajago6/Axv6_One,i/xv6,UIKit0/xv6-1,varunk08/xv6,TheDude05/xv6,preshshah/xv6,sdimitro/xv6,Cheukyin/xv6,bngabonziza/xv6,5kg/xv6,garzon/xv6-public,romanzhg/xv6,romanzhg/xv6,arturosevilla/xv6-turi,khalily/xv6,arianvp/xv6,AZQ1994/xv6,Cealestus/cmpt332Assignment1,roygoldman/xv6-fsprot,MrHohn/CS-OperatingSystem-hw2,kazunobu-fujii/xv6,AskDrCatcher/xv6,WeiranFang/cs518hw3,supr/Xv6,gw/xv6,tehgeekmeister/xv6,phf/xv6-public,pelhamnicholas/xv6,UIKit0/Xv6,williamsandrew/xv6,RicardoParizotto/xv6---stride-scheduling,rafamanzo/ep4-so,MrHohn/cs518hw2,ckkashyap/xv6,UIKit0/Xv6,gzpan123/xv6,BMJHayward/xv6-public,nrahimi/xv6,UIKit0/xv6-1,roygoldman/xv6-sem,walafc0/xv6,chrisdew/xv6,fintler/xv6,fintler/xv6,sigma-random/xv6,prashantkhurana/OS,prashantkhurana/OS,techno/xv6-mist32,t3rm1n4l/xv6,sometimesfood/xv6-public,i/xv6,gmy987/xv6,PINK-FL0YD/xv6-public,bowlofstew/xv6-public,gmy987/xv6,run/xv6,voytovichs/xv6-public,Y-liulian/xv6-public,gw/xv6,lishuwnc/Xv6,techno/xv6-mist32,louisje/xv6,roygoldman/xv6-fsprot,AskDrCatcher/xv6,OrangeTide/xv6-public,pablogventura/xv6-public,rafamanzo/ep2-so-xv6,ManaPoustizadeh/OS-finalProject,howerj/xv6,reutz19/xv6_ass4,vicionator/XV6,supdizh/clean_xv6,panks/Xv6,baboofei/v6rt,lenw/xv6-public,garzon/xv6,shtyd/xv6-lua,oskarth/xv6,kazunobu-fujii/xv6,aclements/sv6,CHRISTOPHERDIEHL/xv6,SarthakCodes/xv6,fintler/xv6,MrHohn/cs518hw2,jmatth/xv6,t3rm1n4l/xv6,pelhamnicholas/xv6,emaadmanzoor/xv6,danluu/Xv6,tehgeekmeister/xv6,OrangeTide/xv6-public,pelhamnicholas/xv6,svdamani/xv6,yubai/ksm_xv6,5kg/xv6,oskarth/xv6,garzon/xv6-public,Cealestus/cmpt332Assignment1,lolosssss/Xv6,s-rah/xv6-permissions,gmy987/xv6,junxu/xv6,descent/xv6,xv6-jp/xv6,codelabs-ch/xv6-muen,bowlofstew/sv6,bowlofstew/sv6,walafc0/xv6,supdizh/clean_xv6,WeiranFang/cs518hw3,liyinhgqw/xv6,justodiaz/xv6,alex0906093/xv6,laisborin/RT-xv6,khalily/xv6,cpehle/xv6,sdharan/xv6-rcu,penguiner/xv6,yubai/ksm_xv6,techno/xv6-mist32,seckcoder/mirror-xv6,yubai/ksm_xv6,SajadAzami/xv6-pm,gburd/xv6,sometimesfood/xv6-public,siddharthv/xv6,shining-yang/xv6,TheDude05/xv6,i/xv6,tenstep/xv6,descent/xv6,MrHohn/CS-OperatingSystem-hw2,CKost/Authorization,davidbalbert/xv6,roygoldman/xv6-sem,johnson-li/xv6-homework,baboofei/v6rt,pablogventura/xv6-public,meilank/CS416-hw1,liorderei/OS_Class,chyka-dev/xv6-public,bngabonziza/xv6-public,liorderei/OS_Class,arturosevilla/xv6-turi,AskDrCatcher/xv6,GautamV/xv6,tlerea1/xv6,bowlofstew/xv6-public,gnudeep/xv6,Cealestus/cmpt332Assignment1,Mifnight/xv6-public,ahorn/xv6,orenherman/xv6-clone,pelhamnicholas/xv6,raman162/CS450,davidbalbert/xv6,SajadAzami/xv6-pm,davidbalbert/xv6,tinti/xv6-ubuntu,vicionator/XV6,aquamme/xv6,t3rm1n4l/xv6,ahorn/xv6,gw/xv6,pekopeko1/xv6,junxu/xv6,nrahimi/xv6,UIKit0/xv6-1,xv6-jp/xv6,juroland/xv6,bowlofstew/xv6-public,ihciah/XV6-OS,emaadmanzoor/xv6,pekopeko1/xv6,v1ta/xv6,rafamanzo/ep4-so,GautamV/xv6,Cealestus/cmpt332Assignment1,tlerea1/xv6,SarthakCodes/xv6,aquamme/xv6,shyandsy/xv6,gzpan123/xv6,film42/xv6,firstblade/xv6,nomadium/xv6,lord021/Assignment2,kazunobu-fujii/xv6,baboofei/v6rt,danluu/Xv6,guilleiguaran/xv6,sometimesfood/xv6,Royvaknin29/OS_Ass1,pekopeko1/xv6-code,myl2821/xv6-fork,humphreyja/Xv6,msyksphinz/xv6-mips,ihciah/XV6-OS,kingsizeme/xv6,roygoldman/xv6-sem,MrHohn/cs518hw2,tlerea1/xv6,galbenor/os162-4,wkatsak/xv6,danrods/xv6Hacks,BMJHayward/xv6-public,HugoTian/xv6,meilank/CS416-hw2,juroland/xv6,howerj/xv6,5kg/xv6,chnpmy/xv6,avana002/xv6,raman162/CS450,ZheyuJin/xv6_reading,siddharthv/xv6,ahorn/xv6,juroland/xv6,myl2821/xv6-fork,arajago6/Axv6_One,niral28/hw1,kingsizeme/xv6,descent/xv6,imagine4077/xv6-public,pablogventura/xv6-public,HugoTian/xv6,chyka-dev/xv6-public,gnosis23/xv6,arturosevilla/xv6-turi,s-rah/xv6-permissions,avana002/xv6,gburd/xv6,tinti/xv6-ubuntu,phf/xv6-public,eewayhsu/xv6,meilank/CS416-hw1,myl2821/xv6-fork,laisborin/RT-xv6,khalily/xv6,logangorence/xv6-public,f13mash/xv6,SajadAzami/xv6-pm,film42/xv6,DuskDragon/xv6,WeiranFang/cs518hw3,gco/xv6,emaadmanzoor/xv6,danluu/Xv6,xujunhai1991/xv6,panks/Xv6,xujunhai1991/xv6,MrHohn/CS-OperatingSystem-hw3,gburd/xv6,ManaPoustizadeh/OS-finalProject,shyandsy/xv6,shyandsy/xv6,kingsizeme/xv6,forwchen/xv6,OrangeTide/xv6-public,garzon/xv6-public,sdharan/xv6-rcu,jmatth/xv6,liyinhgqw/xv6,niral28/hw1,ThomasDq/xv6OS,run/xv6,penguiner/xv6,rlok3000/xv6,liadgi/os163,reutz19/xv6_ass4,nwf/xv6-public,galbenor/os162-4,gw/xv6,chnpmy/xv6,wangxiayang/xv6,wasabiz/xv6,AZQ1994/xv6,gw/xv6,bohaoist/xv6,arcbbb/xv6,Laaia/RT-xv6,ThomasDq/xv6OS,dswann5/os_assignment_3,codelabs-ch/xv6-muen,meilank/CS416-hw2,shyandsy/xv6,nwf/xv6-public,myl2821/xv6-fork,AZQ1994/xv6,preshshah/xv6,TheDude05/xv6,jmatth/xv6,jeffallen/xv6,gmy987/xv6,reutz19/xv6_ass4,MatanGilead/myxv6,wenhuizhang/xv6-public,kongming92/6828-xv6,guilleiguaran/xv6,chrisdew/xv6,sigma-random/xv6,pekopeko1/xv6-code,junxu/xv6,Raysmond/xv6,tehgeekmeister/xv6,aclements/sv6,forwchen/xv6,v1ta/xv6,nomadium/xv6,imagine4077/xv6-public,davidbalbert/xv6,nwolovick/xv6-public,junxu/xv6,seckcoder/mirror-xv6,lishuwnc/Xv6,jgome043/tearos,nrahimi/xv6,supdizh/clean_xv6,robertpd/xv6,nomadium/xv6,shtyd/xv6-lua,techno/xv6-mist32,codelabs-ch/xv6-muen,gburd/xv6,juroland/xv6,phf/xv6-public,wangxiayang/xv6,ckkashyap/xv6,imagine4077/xv6-public,niral28/hw1,penguiner/xv6,garzon/xv6,meilank/CS416-hw1,aquamme/xv6,seckcoder/mirror-xv6,AndreiRO/xv6,wangxiayang/xv6,nwolovick/xv6-public,msyksphinz/xv6-mips,voytovichs/xv6-public,t3rm1n4l/xv6,varunk08/xv6,avana002/xv6,williamsandrew/xv6,sdimitro/xv6,chnpmy/xv6,pekopeko1/xv6,xujunhai1991/xv6,lolosssss/Xv6,ckkashyap/xv6,meilank/CS416-hw2,UIKit0/xv6-1,romanzhg/xv6,MrHohn/CS-OperatingSystem-hw3,KushOza/hw2,arcbbb/xv6,Royvaknin29/OS_Ass1,bowlofstew/sv6,HawxChen/Offical-Version-xv6,robertpd/xv6,louisje/xv6,ShakhMoves/Shakh6,justodiaz/xv6,tlerea1/xv6,galbenor/os162-4,wkatsak/xv6,sdharan/xv6-rcu,orenherman/xv6-clone