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Differential D17773 Diff 50429 sys/ufs/ffs/ffs_rawread.c

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sys/ufs/ffs/ffs_rawread.c

Show First 20 Lines • Show All 68 Lines • ▼ Show 20 Linesstatic int ffs_rawread_main(struct vnode *vp,
struct uio *uio); struct uio *uio);
static int ffs_rawread_sync(struct vnode *vp); static int ffs_rawread_sync(struct vnode *vp);
int ffs_rawread(struct vnode *vp, struct uio *uio, int *workdone); int ffs_rawread(struct vnode *vp, struct uio *uio, int *workdone);
SYSCTL_DECL(_vfs_ffs); SYSCTL_DECL(_vfs_ffs);
static int ffsrawbufcnt = 4; static uma_zone_t ffsraw_pbuf_zone;
SYSCTL_INT(_vfs_ffs, OID_AUTO, ffsrawbufcnt, CTLFLAG_RD, &ffsrawbufcnt, 0,
"Buffers available for raw reads");
static int allowrawread = 1; static int allowrawread = 1;
SYSCTL_INT(_vfs_ffs, OID_AUTO, allowrawread, CTLFLAG_RW, &allowrawread, 0, SYSCTL_INT(_vfs_ffs, OID_AUTO, allowrawread, CTLFLAG_RW, &allowrawread, 0,
"Flag to enable raw reads"); "Flag to enable raw reads");
static int rawreadahead = 1; static int rawreadahead = 1;
SYSCTL_INT(_vfs_ffs, OID_AUTO, rawreadahead, CTLFLAG_RW, &rawreadahead, 0, SYSCTL_INT(_vfs_ffs, OID_AUTO, rawreadahead, CTLFLAG_RW, &rawreadahead, 0,
"Flag to enable readahead for long raw reads"); "Flag to enable readahead for long raw reads");
static void static void
ffs_rawread_setup(void *arg __unused) ffs_rawread_setup(void *arg __unused)
{ {
ffsrawbufcnt = (nswbuf > 100 ) ? (nswbuf - (nswbuf >> 4)) : nswbuf - 8; ffsraw_pbuf_zone = uma_zsecond_create("ffsrawpbuf", pbuf_ctor,
pbuf_dtor, pbuf_init, NULL, pbuf_zone);
uma_zone_set_max(ffsraw_pbuf_zone, (nswbuf > 100 ) ?
(nswbuf - (nswbuf >> 4)) : nswbuf - 8);
} }
SYSINIT(ffs_raw, SI_SUB_VM_CONF, SI_ORDER_ANY, ffs_rawread_setup, NULL); SYSINIT(ffs_raw, SI_SUB_VM_CONF, SI_ORDER_ANY, ffs_rawread_setup, NULL);
static int static int
ffs_rawread_sync(struct vnode *vp) ffs_rawread_sync(struct vnode *vp)
{ {
int error; int error;
int upgraded; int upgraded;
▲ Show 20 Lines • Show All 189 Lines • ▼ Show 20 Linesffs_rawread_main(struct vnode *vp,
nerror = 0; nerror = 0;
bp = NULL; bp = NULL;
nbp = NULL; nbp = NULL;
while (resid > 0) { while (resid > 0) {
if (bp == NULL) { /* Setup first read */ if (bp == NULL) { /* Setup first read */
/* XXX: Leave some bufs for swap */ bp = uma_zalloc(ffsraw_pbuf_zone, M_WAITOK);
bp = getpbuf(&ffsrawbufcnt);
pbgetvp(vp, bp); pbgetvp(vp, bp);
error = ffs_rawread_readahead(vp, udata, offset, error = ffs_rawread_readahead(vp, udata, offset,
resid, td, bp); resid, td, bp);
if (error != 0) if (error != 0)
break; break;
if (resid > bp->b_bufsize) { /* Setup fist readahead */ if (resid > bp->b_bufsize) { /* Setup fist readahead */
/* XXX: Leave bufs for swap */
if (rawreadahead != 0) if (rawreadahead != 0)
nbp = trypbuf(&ffsrawbufcnt); nbp = uma_zalloc(ffsraw_pbuf_zone,
M_NOWAIT);
else else
nbp = NULL; nbp = NULL;
if (nbp != NULL) { if (nbp != NULL) {
pbgetvp(vp, nbp); pbgetvp(vp, nbp);
nerror = ffs_rawread_readahead(vp, nerror = ffs_rawread_readahead(vp,
udata + udata +
bp->b_bufsize, bp->b_bufsize,
offset + offset +
bp->b_bufsize, bp->b_bufsize,
resid - resid -
bp->b_bufsize, bp->b_bufsize,
td, td,
nbp); nbp);
if (nerror) { if (nerror) {
pbrelvp(nbp); pbrelvp(nbp);
relpbuf(nbp, &ffsrawbufcnt); uma_zfree(ffsraw_pbuf_zone,
nbp);
nbp = NULL; nbp = NULL;
} }
} }
} }
} }
bwait(bp, PRIBIO, "rawrd"); bwait(bp, PRIBIO, "rawrd");
vunmapbuf(bp); vunmapbuf(bp);
Show All 24 Lines while (resid > 0) {
} else if (nbp != NULL) { /* Complete read with readahead */ } else if (nbp != NULL) { /* Complete read with readahead */
tbp = bp; tbp = bp;
bp = nbp; bp = nbp;
nbp = tbp; nbp = tbp;
if (resid <= bp->b_bufsize) { /* No more readaheads */ if (resid <= bp->b_bufsize) { /* No more readaheads */
pbrelvp(nbp); pbrelvp(nbp);
relpbuf(nbp, &ffsrawbufcnt); uma_zfree(ffsraw_pbuf_zone, nbp);
nbp = NULL; nbp = NULL;
} else { /* Setup next readahead */ } else { /* Setup next readahead */
nerror = ffs_rawread_readahead(vp, nerror = ffs_rawread_readahead(vp,
udata + udata +
bp->b_bufsize, bp->b_bufsize,
offset + offset +
bp->b_bufsize, bp->b_bufsize,
resid - resid -
bp->b_bufsize, bp->b_bufsize,
td, td,
nbp); nbp);
if (nerror != 0) { if (nerror != 0) {
pbrelvp(nbp); pbrelvp(nbp);
relpbuf(nbp, &ffsrawbufcnt); uma_zfree(ffsraw_pbuf_zone, nbp);
nbp = NULL; nbp = NULL;
} }
} }
} else if (nerror != 0) {/* Deferred Readahead error */ } else if (nerror != 0) {/* Deferred Readahead error */
break; break;
} else if (resid > 0) { /* More to read, no readahead */ } else if (resid > 0) { /* More to read, no readahead */
error = ffs_rawread_readahead(vp, udata, offset, error = ffs_rawread_readahead(vp, udata, offset,
resid, td, bp); resid, td, bp);
if (error != 0) if (error != 0)
break; break;
} }
} }
if (bp != NULL) { if (bp != NULL) {
pbrelvp(bp); pbrelvp(bp);
relpbuf(bp, &ffsrawbufcnt); uma_zfree(ffsraw_pbuf_zone, bp);
} }
if (nbp != NULL) { /* Run down readahead buffer */ if (nbp != NULL) { /* Run down readahead buffer */
bwait(nbp, PRIBIO, "rawrd"); bwait(nbp, PRIBIO, "rawrd");
vunmapbuf(nbp); vunmapbuf(nbp);
pbrelvp(nbp); pbrelvp(nbp);
relpbuf(nbp, &ffsrawbufcnt); uma_zfree(ffsraw_pbuf_zone, nbp);
} }
if (error == 0) if (error == 0)
error = nerror; error = nerror;
PRELE(td->td_proc); PRELE(td->td_proc);
uio->uio_iov->iov_base = udata; uio->uio_iov->iov_base = udata;
uio->uio_resid = resid; uio->uio_resid = resid;
uio->uio_offset = offset; uio->uio_offset = offset;
▲ Show 20 Lines • Show All 64 Lines • Show Last 20 Lines