diff options
Diffstat (limited to 'fs/nfs/blocklayout/extent_tree.c')
| -rw-r--r-- | fs/nfs/blocklayout/extent_tree.c | 602 |
1 files changed, 602 insertions, 0 deletions
diff --git a/fs/nfs/blocklayout/extent_tree.c b/fs/nfs/blocklayout/extent_tree.c new file mode 100644 index 000000000000..31d0b5e53dfd --- /dev/null +++ b/fs/nfs/blocklayout/extent_tree.c @@ -0,0 +1,602 @@ +/* + * Copyright (c) 2014 Christoph Hellwig. + */ + +#include <linux/vmalloc.h> + +#include "blocklayout.h" + +#define NFSDBG_FACILITY NFSDBG_PNFS_LD + +static inline struct pnfs_block_extent * +ext_node(struct rb_node *node) +{ + return rb_entry(node, struct pnfs_block_extent, be_node); +} + +static struct pnfs_block_extent * +ext_tree_first(struct rb_root *root) +{ + struct rb_node *node = rb_first(root); + return node ? ext_node(node) : NULL; +} + +static struct pnfs_block_extent * +ext_tree_prev(struct pnfs_block_extent *be) +{ + struct rb_node *node = rb_prev(&be->be_node); + return node ? ext_node(node) : NULL; +} + +static struct pnfs_block_extent * +ext_tree_next(struct pnfs_block_extent *be) +{ + struct rb_node *node = rb_next(&be->be_node); + return node ? ext_node(node) : NULL; +} + +static inline sector_t +ext_f_end(struct pnfs_block_extent *be) +{ + return be->be_f_offset + be->be_length; +} + +static struct pnfs_block_extent * +__ext_tree_search(struct rb_root *root, sector_t start) +{ + struct rb_node *node = root->rb_node; + struct pnfs_block_extent *be = NULL; + + while (node) { + be = ext_node(node); + if (start < be->be_f_offset) + node = node->rb_left; + else if (start >= ext_f_end(be)) + node = node->rb_right; + else + return be; + } + + if (be) { + if (start < be->be_f_offset) + return be; + + if (start >= ext_f_end(be)) + return ext_tree_next(be); + } + + return NULL; +} + +static bool +ext_can_merge(struct pnfs_block_extent *be1, struct pnfs_block_extent *be2) +{ + if (be1->be_state != be2->be_state) + return false; + if (be1->be_device != be2->be_device) + return false; + + if (be1->be_f_offset + be1->be_length != be2->be_f_offset) + return false; + + if (be1->be_state != PNFS_BLOCK_NONE_DATA && + (be1->be_v_offset + be1->be_length != be2->be_v_offset)) + return false; + + if (be1->be_state == PNFS_BLOCK_INVALID_DATA && + be1->be_tag != be2->be_tag) + return false; + + return true; +} + +static struct pnfs_block_extent * +ext_try_to_merge_left(struct rb_root *root, struct pnfs_block_extent *be) +{ + struct pnfs_block_extent *left = ext_tree_prev(be); + + if (left && ext_can_merge(left, be)) { + left->be_length += be->be_length; + rb_erase(&be->be_node, root); + nfs4_put_deviceid_node(be->be_device); + kfree(be); + return left; + } + + return be; +} + +static struct pnfs_block_extent * +ext_try_to_merge_right(struct rb_root *root, struct pnfs_block_extent *be) +{ + struct pnfs_block_extent *right = ext_tree_next(be); + + if (right && ext_can_merge(be, right)) { + be->be_length += right->be_length; + rb_erase(&right->be_node, root); + nfs4_put_deviceid_node(right->be_device); + kfree(right); + } + + return be; +} + +static void +__ext_tree_insert(struct rb_root *root, + struct pnfs_block_extent *new, bool merge_ok) +{ + struct rb_node **p = &root->rb_node, *parent = NULL; + struct pnfs_block_extent *be; + + while (*p) { + parent = *p; + be = ext_node(parent); + + if (new->be_f_offset < be->be_f_offset) { + if (merge_ok && ext_can_merge(new, be)) { + be->be_f_offset = new->be_f_offset; + if (be->be_state != PNFS_BLOCK_NONE_DATA) + be->be_v_offset = new->be_v_offset; + be->be_length += new->be_length; + be = ext_try_to_merge_left(root, be); + goto free_new; + } + p = &(*p)->rb_left; + } else if (new->be_f_offset >= ext_f_end(be)) { + if (merge_ok && ext_can_merge(be, new)) { + be->be_length += new->be_length; + be = ext_try_to_merge_right(root, be); + goto free_new; + } + p = &(*p)->rb_right; + } else { + BUG(); + } + } + + rb_link_node(&new->be_node, parent, p); + rb_insert_color(&new->be_node, root); + return; +free_new: + nfs4_put_deviceid_node(new->be_device); + kfree(new); +} + +static int +__ext_tree_remove(struct rb_root *root, sector_t start, sector_t end) +{ + struct pnfs_block_extent *be; + sector_t len1 = 0, len2 = 0; + sector_t orig_v_offset; + sector_t orig_len; + + be = __ext_tree_search(root, start); + if (!be) + return 0; + if (be->be_f_offset >= end) + return 0; + + orig_v_offset = be->be_v_offset; + orig_len = be->be_length; + + if (start > be->be_f_offset) + len1 = start - be->be_f_offset; + if (ext_f_end(be) > end) + len2 = ext_f_end(be) - end; + + if (len2 > 0) { + if (len1 > 0) { + struct pnfs_block_extent *new; + + new = kzalloc(sizeof(*new), GFP_ATOMIC); + if (!new) + return -ENOMEM; + + be->be_length = len1; + + new->be_f_offset = end; + if (be->be_state != PNFS_BLOCK_NONE_DATA) { + new->be_v_offset = + orig_v_offset + orig_len - len2; + } + new->be_length = len2; + new->be_state = be->be_state; + new->be_tag = be->be_tag; + new->be_device = nfs4_get_deviceid(be->be_device); + + __ext_tree_insert(root, new, true); + } else { + be->be_f_offset = end; + if (be->be_state != PNFS_BLOCK_NONE_DATA) { + be->be_v_offset = + orig_v_offset + orig_len - len2; + } + be->be_length = len2; + } + } else { + if (len1 > 0) { + be->be_length = len1; + be = ext_tree_next(be); + } + + while (be && ext_f_end(be) <= end) { + struct pnfs_block_extent *next = ext_tree_next(be); + + rb_erase(&be->be_node, root); + nfs4_put_deviceid_node(be->be_device); + kfree(be); + be = next; + } + + if (be && be->be_f_offset < end) { + len1 = ext_f_end(be) - end; + be->be_f_offset = end; + if (be->be_state != PNFS_BLOCK_NONE_DATA) + be->be_v_offset += be->be_length - len1; + be->be_length = len1; + } + } + + return 0; +} + +int +ext_tree_insert(struct pnfs_block_layout *bl, struct pnfs_block_extent *new) +{ + struct pnfs_block_extent *be; + struct rb_root *root; + int err = 0; + + switch (new->be_state) { + case PNFS_BLOCK_READWRITE_DATA: + case PNFS_BLOCK_INVALID_DATA: + root = &bl->bl_ext_rw; + break; + case PNFS_BLOCK_READ_DATA: + case PNFS_BLOCK_NONE_DATA: + root = &bl->bl_ext_ro; + break; + default: + dprintk("invalid extent type\n"); + return -EINVAL; + } + + spin_lock(&bl->bl_ext_lock); +retry: + be = __ext_tree_search(root, new->be_f_offset); + if (!be || be->be_f_offset >= ext_f_end(new)) { + __ext_tree_insert(root, new, true); + } else if (new->be_f_offset >= be->be_f_offset) { + if (ext_f_end(new) <= ext_f_end(be)) { + nfs4_put_deviceid_node(new->be_device); + kfree(new); + } else { + sector_t new_len = ext_f_end(new) - ext_f_end(be); + sector_t diff = new->be_length - new_len; + + new->be_f_offset += diff; + new->be_v_offset += diff; + new->be_length = new_len; + goto retry; + } + } else if (ext_f_end(new) <= ext_f_end(be)) { + new->be_length = be->be_f_offset - new->be_f_offset; + __ext_tree_insert(root, new, true); + } else { + struct pnfs_block_extent *split; + sector_t new_len = ext_f_end(new) - ext_f_end(be); + sector_t diff = new->be_length - new_len; + + split = kmemdup(new, sizeof(*new), GFP_ATOMIC); + if (!split) { + err = -EINVAL; + goto out; + } + + split->be_length = be->be_f_offset - split->be_f_offset; + split->be_device = nfs4_get_deviceid(new->be_device); + __ext_tree_insert(root, split, true); + + new->be_f_offset += diff; + new->be_v_offset += diff; + new->be_length = new_len; + goto retry; + } +out: + spin_unlock(&bl->bl_ext_lock); + return err; +} + +static bool +__ext_tree_lookup(struct rb_root *root, sector_t isect, + struct pnfs_block_extent *ret) +{ + struct rb_node *node; + struct pnfs_block_extent *be; + + node = root->rb_node; + while (node) { + be = ext_node(node); + if (isect < be->be_f_offset) + node = node->rb_left; + else if (isect >= ext_f_end(be)) + node = node->rb_right; + else { + *ret = *be; + return true; + } + } + + return false; +} + +bool +ext_tree_lookup(struct pnfs_block_layout *bl, sector_t isect, + struct pnfs_block_extent *ret, bool rw) +{ + bool found = false; + + spin_lock(&bl->bl_ext_lock); + if (!rw) + found = __ext_tree_lookup(&bl->bl_ext_ro, isect, ret); + if (!found) + found = __ext_tree_lookup(&bl->bl_ext_rw, isect, ret); + spin_unlock(&bl->bl_ext_lock); + + return found; +} + +int ext_tree_remove(struct pnfs_block_layout *bl, bool rw, + sector_t start, sector_t end) +{ + int err, err2; + + spin_lock(&bl->bl_ext_lock); + err = __ext_tree_remove(&bl->bl_ext_ro, start, end); + if (rw) { + err2 = __ext_tree_remove(&bl->bl_ext_rw, start, end); + if (!err) + err = err2; + } + spin_unlock(&bl->bl_ext_lock); + + return err; +} + +static int +ext_tree_split(struct rb_root *root, struct pnfs_block_extent *be, + sector_t split) +{ + struct pnfs_block_extent *new; + sector_t orig_len = be->be_length; + + new = kzalloc(sizeof(*new), GFP_ATOMIC); + if (!new) + return -ENOMEM; + + be->be_length = split - be->be_f_offset; + + new->be_f_offset = split; + if (be->be_state != PNFS_BLOCK_NONE_DATA) + new->be_v_offset = be->be_v_offset + be->be_length; + new->be_length = orig_len - be->be_length; + new->be_state = be->be_state; + new->be_tag = be->be_tag; + new->be_device = nfs4_get_deviceid(be->be_device); + + __ext_tree_insert(root, new, false); + return 0; +} + +int +ext_tree_mark_written(struct pnfs_block_layout *bl, sector_t start, + sector_t len) +{ + struct rb_root *root = &bl->bl_ext_rw; + sector_t end = start + len; + struct pnfs_block_extent *be; + int err = 0; + + spin_lock(&bl->bl_ext_lock); + /* + * First remove all COW extents or holes from written to range. + */ + err = __ext_tree_remove(&bl->bl_ext_ro, start, end); + if (err) + goto out; + + /* + * Then mark all invalid extents in the range as written to. + */ + for (be = __ext_tree_search(root, start); be; be = ext_tree_next(be)) { + if (be->be_f_offset >= end) + break; + + if (be->be_state != PNFS_BLOCK_INVALID_DATA || be->be_tag) + continue; + + if (be->be_f_offset < start) { + struct pnfs_block_extent *left = ext_tree_prev(be); + + if (left && ext_can_merge(left, be)) { + sector_t diff = start - be->be_f_offset; + + left->be_length += diff; + + be->be_f_offset += diff; + be->be_v_offset += diff; + be->be_length -= diff; + } else { + err = ext_tree_split(root, be, start); + if (err) + goto out; + } + } + + if (ext_f_end(be) > end) { + struct pnfs_block_extent *right = ext_tree_next(be); + + if (right && ext_can_merge(be, right)) { + sector_t diff = end - be->be_f_offset; + + be->be_length -= diff; + + right->be_f_offset -= diff; + right->be_v_offset -= diff; + right->be_length += diff; + } else { + err = ext_tree_split(root, be, end); + if (err) + goto out; + } + } + + if (be->be_f_offset >= start && ext_f_end(be) <= end) { + be->be_tag = EXTENT_WRITTEN; + be = ext_try_to_merge_left(root, be); + be = ext_try_to_merge_right(root, be); + } + } +out: + spin_unlock(&bl->bl_ext_lock); + return err; +} + +static void ext_tree_free_commitdata(struct nfs4_layoutcommit_args *arg, + size_t buffer_size) +{ + if (arg->layoutupdate_pages != &arg->layoutupdate_page) { + int nr_pages = DIV_ROUND_UP(buffer_size, PAGE_SIZE), i; + + for (i = 0; i < nr_pages; i++) + put_page(arg->layoutupdate_pages[i]); + kfree(arg->layoutupdate_pages); + } else { + put_page(arg->layoutupdate_page); + } +} + +static int ext_tree_encode_commit(struct pnfs_block_layout *bl, __be32 *p, + size_t buffer_size, size_t *count) +{ + struct pnfs_block_extent *be; + int ret = 0; + + spin_lock(&bl->bl_ext_lock); + for (be = ext_tree_first(&bl->bl_ext_rw); be; be = ext_tree_next(be)) { + if (be->be_state != PNFS_BLOCK_INVALID_DATA || + be->be_tag != EXTENT_WRITTEN) + continue; + + (*count)++; + if (*count * BL_EXTENT_SIZE > buffer_size) { + /* keep counting.. */ + ret = -ENOSPC; + continue; + } + + p = xdr_encode_opaque_fixed(p, be->be_device->deviceid.data, + NFS4_DEVICEID4_SIZE); + p = xdr_encode_hyper(p, be->be_f_offset << SECTOR_SHIFT); + p = xdr_encode_hyper(p, be->be_length << SECTOR_SHIFT); + p = xdr_encode_hyper(p, 0LL); + *p++ = cpu_to_be32(PNFS_BLOCK_READWRITE_DATA); + + be->be_tag = EXTENT_COMMITTING; + } + spin_unlock(&bl->bl_ext_lock); + + return ret; +} + +int +ext_tree_prepare_commit(struct nfs4_layoutcommit_args *arg) +{ + struct pnfs_block_layout *bl = BLK_LO2EXT(NFS_I(arg->inode)->layout); + size_t count = 0, buffer_size = PAGE_SIZE; + __be32 *start_p; + int ret; + + dprintk("%s enter\n", __func__); + + arg->layoutupdate_page = alloc_page(GFP_NOFS); + if (!arg->layoutupdate_page) + return -ENOMEM; + start_p = page_address(arg->layoutupdate_page); + arg->layoutupdate_pages = &arg->layoutupdate_page; + +retry: + ret = ext_tree_encode_commit(bl, start_p + 1, buffer_size, &count); + if (unlikely(ret)) { + ext_tree_free_commitdata(arg, buffer_size); + + buffer_size = sizeof(__be32) + BL_EXTENT_SIZE * count; + count = 0; + + arg->layoutupdate_pages = + kcalloc(DIV_ROUND_UP(buffer_size, PAGE_SIZE), + sizeof(struct page *), GFP_NOFS); + if (!arg->layoutupdate_pages) + return -ENOMEM; + + start_p = __vmalloc(buffer_size, GFP_NOFS, PAGE_KERNEL); + if (!start_p) { + kfree(arg->layoutupdate_pages); + return -ENOMEM; + } + + goto retry; + } + + *start_p = cpu_to_be32(count); + arg->layoutupdate_len = sizeof(__be32) + BL_EXTENT_SIZE * count; + + if (unlikely(arg->layoutupdate_pages != &arg->layoutupdate_page)) { + __be32 *p = start_p; + int i = 0; + + for (p = start_p; + p < start_p + arg->layoutupdate_len; + p += PAGE_SIZE) { + arg->layoutupdate_pages[i++] = vmalloc_to_page(p); + } + } + + dprintk("%s found %zu ranges\n", __func__, count); + return 0; +} + +void +ext_tree_mark_committed(struct nfs4_layoutcommit_args *arg, int status) +{ + struct pnfs_block_layout *bl = BLK_LO2EXT(NFS_I(arg->inode)->layout); + struct rb_root *root = &bl->bl_ext_rw; + struct pnfs_block_extent *be; + + dprintk("%s status %d\n", __func__, status); + + ext_tree_free_commitdata(arg, arg->layoutupdate_len); + + spin_lock(&bl->bl_ext_lock); + for (be = ext_tree_first(root); be; be = ext_tree_next(be)) { + if (be->be_state != PNFS_BLOCK_INVALID_DATA || + be->be_tag != EXTENT_COMMITTING) + continue; + + if (status) { + /* + * Mark as written and try again. + * + * XXX: some real error handling here wouldn't hurt.. + */ + be->be_tag = EXTENT_WRITTEN; + } else { + be->be_state = PNFS_BLOCK_READWRITE_DATA; + be->be_tag = 0; + } + + be = ext_try_to_merge_left(root, be); + be = ext_try_to_merge_right(root, be); + } + spin_unlock(&bl->bl_ext_lock); +} |