diff options
| -rw-r--r-- | sys/fs/specfs/spec_vnops.c | 19 | ||||
| -rw-r--r-- | sys/kern/kern_physio.c | 14 | ||||
| -rw-r--r-- | sys/kern/vfs_bio.c | 47 | ||||
| -rw-r--r-- | sys/sys/buf.h | 2 |
4 files changed, 46 insertions, 36 deletions
diff --git a/sys/fs/specfs/spec_vnops.c b/sys/fs/specfs/spec_vnops.c index 4f2c145..b53c819 100644 --- a/sys/fs/specfs/spec_vnops.c +++ b/sys/fs/specfs/spec_vnops.c @@ -123,8 +123,6 @@ spec_vnoperate(ap) return (VOCALL(spec_vnodeop_p, ap->a_desc->vdesc_offset, ap)); } -static void spec_getpages_iodone(struct buf *bp); - /* * Open a special file. */ @@ -689,15 +687,6 @@ spec_advlock(ap) return (ap->a_flags & F_FLOCK ? EOPNOTSUPP : EINVAL); } -static void -spec_getpages_iodone(bp) - struct buf *bp; -{ - - bp->b_flags |= B_DONE; - wakeup(bp); -} - static int spec_getpages(ap) struct vop_getpages_args *ap; @@ -755,7 +744,7 @@ spec_getpages(ap) /* Build a minimal buffer header. */ bp->b_iocmd = BIO_READ; - bp->b_iodone = spec_getpages_iodone; + bp->b_iodone = bdone; /* B_PHYS is not set, but it is nice to fill this in. */ KASSERT(bp->b_rcred == NOCRED, ("leaking read ucred")); @@ -778,11 +767,7 @@ spec_getpages(ap) spec_xstrategy(bp->b_vp, bp); s = splbio(); - - /* We definitely need to be at splbio here. */ - while ((bp->b_flags & B_DONE) == 0) - tsleep(bp, PVM, "spread", 0); - + bwait(bp, PVM, "spread"); splx(s); if ((bp->b_ioflags & BIO_ERROR) != 0) { diff --git a/sys/kern/kern_physio.c b/sys/kern/kern_physio.c index 01e3750..aebbbdb 100644 --- a/sys/kern/kern_physio.c +++ b/sys/kern/kern_physio.c @@ -30,12 +30,6 @@ #include <vm/vm.h> #include <vm/vm_extern.h> -static void -physwakeup(struct buf *bp) -{ - wakeup(bp); -} - int physio(dev_t dev, struct uio *uio, int ioflag) { @@ -68,7 +62,7 @@ physio(dev_t dev, struct uio *uio, int ioflag) else bp->b_iocmd = BIO_WRITE; bp->b_dev = dev; - bp->b_iodone = physwakeup; + bp->b_iodone = bdone; bp->b_data = uio->uio_iov[i].iov_base; bp->b_bcount = uio->uio_iov[i].iov_len; bp->b_offset = uio->uio_offset; @@ -116,8 +110,10 @@ physio(dev_t dev, struct uio *uio, int ioflag) DEV_STRATEGY(bp); spl = splbio(); - while ((bp->b_flags & B_DONE) == 0) - tsleep(bp, PRIBIO, "physstr", 0); + if (uio->uio_rw == UIO_READ) + bwait(bp, PRIBIO, "physrd"); + else + bwait(bp, PRIBIO, "physwr"); splx(spl); if (uio->uio_segflg == UIO_USERSPACE) diff --git a/sys/kern/vfs_bio.c b/sys/kern/vfs_bio.c index 7785e9d..a5c6760 100644 --- a/sys/kern/vfs_bio.c +++ b/sys/kern/vfs_bio.c @@ -213,6 +213,12 @@ static int needsbuffer; static struct mtx nblock; /* + * Lock that protects against bwait()/bdone()/B_DONE races. + */ + +static struct mtx bdonelock; + +/* * Definitions for the buffer free lists. */ #define BUFFER_QUEUES 6 /* number of free buffer queues */ @@ -484,6 +490,7 @@ bufinit(void) mtx_init(&rbreqlock, "runningbufspace lock", NULL, MTX_DEF); mtx_init(&nblock, "needsbuffer lock", NULL, MTX_DEF); mtx_init(&bdlock, "buffer daemon lock", NULL, MTX_DEF); + mtx_init(&bdonelock, "bdone lock", NULL, MTX_DEF); /* next, make a null set of free lists */ for (i = 0; i < BUFFER_QUEUES; i++) @@ -2925,11 +2932,13 @@ allocbuf(struct buf *bp, int size) void biodone(struct bio *bp) { + mtx_lock(&bdonelock); bp->bio_flags |= BIO_DONE; + if (bp->bio_done == NULL) + wakeup(bp); + mtx_unlock(&bdonelock); if (bp->bio_done != NULL) bp->bio_done(bp); - else - wakeup(bp); } /* @@ -2942,8 +2951,10 @@ int biowait(struct bio *bp, const char *wchan) { + mtx_lock(&bdonelock); while ((bp->bio_flags & BIO_DONE) == 0) - msleep(bp, NULL, PRIBIO, wchan, hz / 10); + msleep(bp, &bdonelock, PRIBIO, wchan, hz / 10); + mtx_unlock(&bdonelock); if (bp->bio_error != 0) return (bp->bio_error); if (!(bp->bio_flags & BIO_ERROR)) @@ -3002,12 +3013,10 @@ bufwait(register struct buf * bp) int s; s = splbio(); - while ((bp->b_flags & B_DONE) == 0) { - if (bp->b_iocmd == BIO_READ) - tsleep(bp, PRIBIO, "biord", 0); - else - tsleep(bp, PRIBIO, "biowr", 0); - } + if (bp->b_iocmd == BIO_READ) + bwait(bp, PRIBIO, "biord"); + else + bwait(bp, PRIBIO, "biowr"); splx(s); if (bp->b_flags & B_EINTR) { bp->b_flags &= ~B_EINTR; @@ -3214,7 +3223,7 @@ bufdone(struct buf *bp) else bqrelse(bp); } else { - wakeup(bp); + bdone(bp); } splx(s); } @@ -3697,6 +3706,24 @@ vunmapbuf(struct buf *bp) bp->b_data = bp->b_saveaddr; } +void +bdone(struct buf *bp) +{ + mtx_lock(&bdonelock); + bp->b_flags |= B_DONE; + wakeup(bp); + mtx_unlock(&bdonelock); +} + +void +bwait(struct buf *bp, u_char pri, const char *wchan) +{ + mtx_lock(&bdonelock); + while ((bp->b_flags & B_DONE) == 0) + msleep(bp, &bdonelock, pri, wchan, 0); + mtx_unlock(&bdonelock); +} + #include "opt_ddb.h" #ifdef DDB #include <ddb/ddb.h> diff --git a/sys/sys/buf.h b/sys/sys/buf.h index f8a2416..60d0d42 100644 --- a/sys/sys/buf.h +++ b/sys/sys/buf.h @@ -528,6 +528,8 @@ void pbrelvp(struct buf *); int allocbuf(struct buf *bp, int size); void reassignbuf(struct buf *, struct vnode *); struct buf *trypbuf(int *); +void bwait(struct buf *, u_char, const char *); +void bdone(struct buf *); #endif /* _KERNEL */ |
