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Date: Mon, 2 Oct 2006 18:12:42 -0700 (PDT)
From: Shane Adams <adamsch1@yahoo.com>
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Subject: curiosity between bread and UFS_BALLOC on struct buf
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Hey all,=0A=0AI've been puzzling with a bit of code.  I'm creating a file f=
rom within a kernel module, that works fine, but I've got a question if per=
haps I'm missing something:=0A=0AI use UFS_BALLOC to allocate some space.  =
That function has a struct buf thats returned.  What I would expect is that=
 I could manipulate the bp->b_data field then do a bwrite and have my chang=
es saved.  Doesnt work that way.  Only way=0AI can get it to work is=0A=0A1=
 UFS_BALLOC( ... )=0A=0A2 bwrite( .. )=0A=0A3 bread( ... )=0A=0A4 /* Make c=
hanges to what I read */=0A=0A5 bwrite()=0A=0ASeems like I could get rid of=
, 2 and 3.  I'm not sure why I have to bwrite the buffer returned from UFS_=
BALLOC.  I dug around and there are a few examples of where ffs/ufs manipul=
ate the buffer returned from UFS_BALLOC so I am guessing I'm missing a flag=
 or something.=0A=0AHope the question is clear enough!=0A=0ACheers,=0A  Sha=
ne=0A=0A