diff options
Diffstat (limited to 'sys/kern/vfs_bio.c')
| -rw-r--r-- | sys/kern/vfs_bio.c | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/sys/kern/vfs_bio.c b/sys/kern/vfs_bio.c index 675ecab..b278f6c 100644 --- a/sys/kern/vfs_bio.c +++ b/sys/kern/vfs_bio.c @@ -18,7 +18,7 @@ * 5. Modifications may be freely made to this file if the above conditions * are met. * - * $Id: vfs_bio.c,v 1.94 1996/06/30 05:17:08 davidg Exp $ + * $Id: vfs_bio.c,v 1.95 1996/08/04 20:13:08 phk Exp $ */ /* @@ -113,6 +113,9 @@ static struct bqueues bufqueues[BUFFER_QUEUES]; extern int vm_swap_size; #define BUF_MAXUSE 8 +/* +#define NO_B_MALLOC +*/ /* * Initialize buffer headers and related structures. @@ -844,7 +847,7 @@ fillbuf: bp->b_data = buffers_kva + (bp - buf) * MAXBSIZE; bp->b_dirtyoff = bp->b_dirtyend = 0; bp->b_validoff = bp->b_validend = 0; - bp->b_usecount = 2; + bp->b_usecount = 4; if (bufspace >= maxbufspace + nbyteswritten) { bp->b_flags |= B_INVAL; brelse(bp); @@ -1120,12 +1123,15 @@ allocbuf(struct buf * bp, int size) * Just get anonymous memory from the kernel */ mbsize = (size + DEV_BSIZE - 1) & ~(DEV_BSIZE - 1); +#if !defined(NO_B_MALLOC) if (bp->b_flags & B_MALLOC) newbsize = mbsize; else +#endif newbsize = round_page(size); if (newbsize < bp->b_bufsize) { +#if !defined(NO_B_MALLOC) /* * malloced buffers are not shrunk */ @@ -1143,11 +1149,13 @@ allocbuf(struct buf * bp, int size) } return 1; } +#endif vm_hold_free_pages( bp, (vm_offset_t) bp->b_data + newbsize, (vm_offset_t) bp->b_data + bp->b_bufsize); } else if (newbsize > bp->b_bufsize) { +#if !defined(NO_B_MALLOC) /* * We only use malloced memory on the first allocation. * and revert to page-allocated memory when the buffer grows. @@ -1164,8 +1172,10 @@ allocbuf(struct buf * bp, int size) bufmallocspace += mbsize; return 1; } +#endif origbuf = NULL; origbufsize = 0; +#if !defined(NO_B_MALLOC) /* * If the buffer is growing on it's other-than-first allocation, * then we revert to the page-allocation scheme. @@ -1180,14 +1190,17 @@ allocbuf(struct buf * bp, int size) bp->b_flags &= ~B_MALLOC; newbsize = round_page(newbsize); } +#endif vm_hold_load_pages( bp, (vm_offset_t) bp->b_data + bp->b_bufsize, (vm_offset_t) bp->b_data + newbsize); +#if !defined(NO_B_MALLOC) if (origbuf) { bcopy(origbuf, bp->b_data, origbufsize); free(origbuf, M_BIOBUF); } +#endif } } else { vm_page_t m; @@ -1196,8 +1209,10 @@ allocbuf(struct buf * bp, int size) newbsize = (size + DEV_BSIZE - 1) & ~(DEV_BSIZE - 1); desiredpages = (round_page(newbsize) >> PAGE_SHIFT); +#if !defined(NO_B_MALLOC) if (bp->b_flags & B_MALLOC) panic("allocbuf: VMIO buffer can't be malloced"); +#endif if (newbsize < bp->b_bufsize) { if (desiredpages < bp->b_npages) { |
