diff options
Diffstat (limited to 'module/zfs/dbuf.c')
| -rw-r--r-- | module/zfs/dbuf.c | 17 |
1 files changed, 14 insertions, 3 deletions
diff --git a/module/zfs/dbuf.c b/module/zfs/dbuf.c index f05190b66..e487e469f 100644 --- a/module/zfs/dbuf.c +++ b/module/zfs/dbuf.c @@ -918,7 +918,7 @@ dbuf_loan_arcbuf(dmu_buf_impl_t *db) * provided. */ uint64_t -dbuf_whichblock(dnode_t *dn, int64_t level, uint64_t offset) +dbuf_whichblock(const dnode_t *dn, const int64_t level, const uint64_t offset) { if (dn->dn_datablkshift != 0 && dn->dn_indblkshift != 0) { /* @@ -940,8 +940,19 @@ dbuf_whichblock(dnode_t *dn, int64_t level, uint64_t offset) * = offset >> (datablkshift + level * * (indblkshift - SPA_BLKPTRSHIFT)) */ - return (offset >> (dn->dn_datablkshift + level * - (dn->dn_indblkshift - SPA_BLKPTRSHIFT))); + + const unsigned exp = dn->dn_datablkshift + + level * (dn->dn_indblkshift - SPA_BLKPTRSHIFT); + + if (exp >= 8 * sizeof (offset)) { + /* This only happens on the highest indirection level */ + ASSERT3U(level, ==, dn->dn_nlevels - 1); + return (0); + } + + ASSERT3U(exp, <, 8 * sizeof (offset)); + + return (offset >> exp); } else { ASSERT3U(offset, <, dn->dn_datablksz); return (0); |