diff options
Diffstat (limited to 'fs/nfs/blocklayout/extents.c')
| -rw-r--r-- | fs/nfs/blocklayout/extents.c | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/fs/nfs/blocklayout/extents.c b/fs/nfs/blocklayout/extents.c index 84bf24087720f..7521940dcca5e 100644 --- a/fs/nfs/blocklayout/extents.c +++ b/fs/nfs/blocklayout/extents.c @@ -329,6 +329,73 @@ static void print_clist(struct list_head *list, unsigned int count) } } +/* Note: In theory, we should do more checking that devid's match between + * old and new, but if they don't, the lists are too corrupt to salvage anyway. + */ +/* Note this is very similar to bl_add_merge_extent */ +static void add_to_commitlist(struct pnfs_block_layout *bl, + struct pnfs_block_short_extent *new) +{ + struct list_head *clist = &bl->bl_commit; + struct pnfs_block_short_extent *old, *save; + sector_t end = new->bse_f_offset + new->bse_length; + + dprintk("%s enter\n", __func__); + print_short_extent(new); + print_clist(clist, bl->bl_count); + bl->bl_count++; + /* Scan for proper place to insert, extending new to the left + * as much as possible. + */ + list_for_each_entry_safe(old, save, clist, bse_node) { + if (new->bse_f_offset < old->bse_f_offset) + break; + if (end <= old->bse_f_offset + old->bse_length) { + /* Range is already in list */ + bl->bl_count--; + kfree(new); + return; + } else if (new->bse_f_offset <= + old->bse_f_offset + old->bse_length) { + /* new overlaps or abuts existing be */ + if (new->bse_mdev == old->bse_mdev) { + /* extend new to fully replace old */ + new->bse_length += new->bse_f_offset - + old->bse_f_offset; + new->bse_f_offset = old->bse_f_offset; + list_del(&old->bse_node); + bl->bl_count--; + kfree(old); + } + } + } + /* Note that if we never hit the above break, old will not point to a + * valid extent. However, in that case &old->bse_node==list. + */ + list_add_tail(&new->bse_node, &old->bse_node); + /* Scan forward for overlaps. If we find any, extend new and + * remove the overlapped extent. + */ + old = list_prepare_entry(new, clist, bse_node); + list_for_each_entry_safe_continue(old, save, clist, bse_node) { + if (end < old->bse_f_offset) + break; + /* new overlaps or abuts old */ + if (new->bse_mdev == old->bse_mdev) { + if (end < old->bse_f_offset + old->bse_length) { + /* extend new to fully cover old */ + end = old->bse_f_offset + old->bse_length; + new->bse_length = end - new->bse_f_offset; + } + list_del(&old->bse_node); + bl->bl_count--; + kfree(old); + } + } + dprintk("%s: after merging\n", __func__); + print_clist(clist, bl->bl_count); +} + static void print_bl_extent(struct pnfs_block_extent *be) { dprintk("PRINT EXTENT extent %p\n", be); @@ -539,6 +606,34 @@ bl_find_get_extent(struct pnfs_block_layout *bl, sector_t isect, return ret; } +/* Similar to bl_find_get_extent, but called with lock held, and ignores cow */ +static struct pnfs_block_extent * +bl_find_get_extent_locked(struct pnfs_block_layout *bl, sector_t isect) +{ + struct pnfs_block_extent *be, *ret = NULL; + int i; + + dprintk("%s enter with isect %llu\n", __func__, (u64)isect); + for (i = 0; i < EXTENT_LISTS; i++) { + if (ret) + break; + list_for_each_entry_reverse(be, &bl->bl_extents[i], be_node) { + if (isect >= be->be_f_offset + be->be_length) + break; + if (isect >= be->be_f_offset) { + /* We have found an extent */ + dprintk("%s Get %p (%i)\n", __func__, be, + atomic_read(&be->be_refcnt.refcount)); + kref_get(&be->be_refcnt); + ret = be; + break; + } + } + } + print_bl_extent(ret); + return ret; +} + int encode_pnfs_block_layoutupdate(struct pnfs_block_layout *bl, struct xdr_stream *xdr, @@ -628,3 +723,118 @@ _front_merge(struct pnfs_block_extent *be, struct list_head *head, kfree(storage); return be; } + +static u64 +set_to_rw(struct pnfs_block_layout *bl, u64 offset, u64 length) +{ + u64 rv = offset + length; + struct pnfs_block_extent *be, *e1, *e2, *e3, *new, *old; + struct pnfs_block_extent *children[3]; + struct pnfs_block_extent *merge1 = NULL, *merge2 = NULL; + int i = 0, j; + + dprintk("%s(%llu, %llu)\n", __func__, offset, length); + /* Create storage for up to three new extents e1, e2, e3 */ + e1 = kmalloc(sizeof(*e1), GFP_ATOMIC); + e2 = kmalloc(sizeof(*e2), GFP_ATOMIC); + e3 = kmalloc(sizeof(*e3), GFP_ATOMIC); + /* BUG - we are ignoring any failure */ + if (!e1 || !e2 || !e3) + goto out_nosplit; + + spin_lock(&bl->bl_ext_lock); + be = bl_find_get_extent_locked(bl, offset); + rv = be->be_f_offset + be->be_length; + if (be->be_state != PNFS_BLOCK_INVALID_DATA) { + spin_unlock(&bl->bl_ext_lock); + goto out_nosplit; + } + /* Add e* to children, bumping e*'s krefs */ + if (be->be_f_offset != offset) { + _prep_new_extent(e1, be, be->be_f_offset, + offset - be->be_f_offset, + PNFS_BLOCK_INVALID_DATA); + children[i++] = e1; + print_bl_extent(e1); + } else + merge1 = e1; + _prep_new_extent(e2, be, offset, + min(length, be->be_f_offset + be->be_length - offset), + PNFS_BLOCK_READWRITE_DATA); + children[i++] = e2; + print_bl_extent(e2); + if (offset + length < be->be_f_offset + be->be_length) { + _prep_new_extent(e3, be, e2->be_f_offset + e2->be_length, + be->be_f_offset + be->be_length - + offset - length, + PNFS_BLOCK_INVALID_DATA); + children[i++] = e3; + print_bl_extent(e3); + } else + merge2 = e3; + + /* Remove be from list, and insert the e* */ + /* We don't get refs on e*, since this list is the base reference + * set when init'ed. + */ + if (i < 3) + children[i] = NULL; + new = children[0]; + list_replace(&be->be_node, &new->be_node); + bl_put_extent(be); + new = _front_merge(new, &bl->bl_extents[RW_EXTENT], merge1); + for (j = 1; j < i; j++) { + old = new; + new = children[j]; + list_add(&new->be_node, &old->be_node); + } + if (merge2) { + /* This is a HACK, should just create a _back_merge function */ + new = list_entry(new->be_node.next, + struct pnfs_block_extent, be_node); + new = _front_merge(new, &bl->bl_extents[RW_EXTENT], merge2); + } + spin_unlock(&bl->bl_ext_lock); + + /* Since we removed the base reference above, be is now scheduled for + * destruction. + */ + bl_put_extent(be); + dprintk("%s returns %llu after split\n", __func__, rv); + return rv; + + out_nosplit: + kfree(e1); + kfree(e2); + kfree(e3); + dprintk("%s returns %llu without splitting\n", __func__, rv); + return rv; +} + +void +clean_pnfs_block_layoutupdate(struct pnfs_block_layout *bl, + const struct nfs4_layoutcommit_args *arg, + int status) +{ + struct pnfs_block_short_extent *lce, *save; + + dprintk("%s status %d\n", __func__, status); + list_for_each_entry_safe(lce, save, &bl->bl_committing, bse_node) { + if (likely(!status)) { + u64 offset = lce->bse_f_offset; + u64 end = offset + lce->bse_length; + + do { + offset = set_to_rw(bl, offset, end - offset); + } while (offset < end); + list_del(&lce->bse_node); + + kfree(lce); + } else { + list_del(&lce->bse_node); + spin_lock(&bl->bl_ext_lock); + add_to_commitlist(bl, lce); + spin_unlock(&bl->bl_ext_lock); + } + } +} |