--- /dev/null
+/*
+ * 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);
+}
Code Review / kvmfornfv.git / blobdiff