From 8ef97622caa2d5f78d1dc58ab918e2fbfa9b357a Mon Sep 17 00:00:00 2001 From: Chris Mason Date: Mon, 26 Mar 2007 10:15:30 -0400 Subject: Btrfs: add a radix back bit tree Signed-off-by: Chris Mason diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile index be7d74c..5346f70 100644 --- a/fs/btrfs/Makefile +++ b/fs/btrfs/Makefile @@ -3,7 +3,8 @@ ifneq ($(KERNELRELEASE),) obj-m := btrfs.o btrfs-y := super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \ - hash.o file-item.o inode-item.o inode-map.o disk-io.o transaction.o + hash.o file-item.o inode-item.o inode-map.o disk-io.o \ + transaction.o bit-radix.o #btrfs-y := ctree.o disk-io.o radix-tree.o extent-tree.o print-tree.o \ # root-tree.o dir-item.o hash.o file-item.o inode-item.o \ diff --git a/fs/btrfs/bit-radix.c b/fs/btrfs/bit-radix.c new file mode 100644 index 0000000..43807cc --- /dev/null +++ b/fs/btrfs/bit-radix.c @@ -0,0 +1,107 @@ +#include +#include "bit-radix.h" + +#define BIT_ARRAY_BYTES 256 +#define BIT_RADIX_BITS_PER_ARRAY ((BIT_ARRAY_BYTES - sizeof(unsigned long)) * 8) + +int set_radix_bit(struct radix_tree_root *radix, unsigned long bit) +{ + unsigned long *bits; + unsigned long slot; + int bit_slot; + int ret; + + slot = bit / BIT_RADIX_BITS_PER_ARRAY; + bit_slot = bit % BIT_RADIX_BITS_PER_ARRAY; + + bits = radix_tree_lookup(radix, slot); + if (!bits) { + bits = kmalloc(BIT_ARRAY_BYTES, GFP_NOIO); + if (!bits) + return -ENOMEM; + memset(bits + 1, 0, BIT_ARRAY_BYTES - sizeof(unsigned long)); + bits[0] = slot; + ret = radix_tree_insert(radix, slot, bits); + if (ret) + return ret; + } + set_bit(bit_slot, bits + 1); + return 0; +} + +int test_radix_bit(struct radix_tree_root *radix, unsigned long bit) +{ + unsigned long *bits; + unsigned long slot; + int bit_slot; + + slot = bit / BIT_RADIX_BITS_PER_ARRAY; + bit_slot = bit % BIT_RADIX_BITS_PER_ARRAY; + + bits = radix_tree_lookup(radix, slot); + if (!bits) + return 0; + return test_bit(bit_slot, bits + 1); +} + +int clear_radix_bit(struct radix_tree_root *radix, unsigned long bit) +{ + unsigned long *bits; + unsigned long slot; + int bit_slot; + int i; + int empty = 1; + + slot = bit / BIT_RADIX_BITS_PER_ARRAY; + bit_slot = bit % BIT_RADIX_BITS_PER_ARRAY; + + bits = radix_tree_lookup(radix, slot); + if (!bits) + return 0; + clear_bit(bit_slot, bits + 1); + + for (i = 1; i < BIT_ARRAY_BYTES / sizeof(unsigned long); i++) { + if (bits[i]) { + empty = 0; + break; + } + } + + if (empty) { + bits = radix_tree_delete(radix, slot); + BUG_ON(!bits); + } + return 0; +} + +int find_first_radix_bit(struct radix_tree_root *radix, unsigned long *retbits, + int nr) +{ + unsigned long *bits; + unsigned long *gang[4]; + int found; + int ret; + int i; + int total_found = 0; + + ret = radix_tree_gang_lookup(radix, (void *)&gang, 0, ARRAY_SIZE(gang)); + for (i = 0; i < ret && nr > 0; i++) { + found = 0; + bits = gang[i]; + while(nr > 0) { + found = find_next_bit(bits + 1, + BIT_RADIX_BITS_PER_ARRAY, + found); + if (found < BIT_RADIX_BITS_PER_ARRAY) { + *retbits = bits[0] * + BIT_RADIX_BITS_PER_ARRAY + found; + retbits++; + nr--; + total_found++; + found++; + } else + break; + } + } + return total_found; +} diff --git a/fs/btrfs/bit-radix.h b/fs/btrfs/bit-radix.h new file mode 100644 index 0000000..56aad4c --- /dev/null +++ b/fs/btrfs/bit-radix.h @@ -0,0 +1,15 @@ +#ifndef __BIT_RADIX__ +#define __BIT_RADIX__ +#include + +int set_radix_bit(struct radix_tree_root *radix, unsigned long bit); +int test_radix_bit(struct radix_tree_root *radix, unsigned long bit); +int clear_radix_bit(struct radix_tree_root *radix, unsigned long bit); +int find_first_radix_bit(struct radix_tree_root *radix, unsigned long *retbits, + int nr); + +static inline void init_bit_radix(struct radix_tree_root *radix) +{ + INIT_RADIX_TREE(radix, GFP_NOFS); +} +#endif diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index 68cafae..0aa1052 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -1,8 +1,8 @@ #ifndef __BTRFS__ #define __BTRFS__ -#include #include +#include "bit-radix.h" struct btrfs_trans_handle; struct btrfs_transaction; @@ -222,6 +222,7 @@ struct btrfs_fs_info { struct btrfs_root *inode_root; struct btrfs_key current_insert; struct btrfs_key last_insert; + struct radix_tree_root pending_del_radix; struct radix_tree_root pinned_radix; u64 last_inode_alloc; u64 last_inode_alloc_dirid; diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index e32ddff..758a62a 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -104,7 +104,8 @@ struct btrfs_root *open_ctree(struct super_block *sb, /* FIXME: don't be stupid */ if (!btrfs_super_root(disk_super)) return NULL; - INIT_RADIX_TREE(&fs_info->pinned_radix, GFP_KERNEL); + init_bit_radix(&fs_info->pinned_radix); + init_bit_radix(&fs_info->pending_del_radix); fs_info->running_transaction = NULL; fs_info->fs_root = root; fs_info->tree_root = tree_root; diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 369b960..b141042 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -1,5 +1,4 @@ #include -#include #include "ctree.h" #include "disk-io.h" #include "print-tree.h" @@ -12,15 +11,6 @@ static int finish_current_insert(struct btrfs_trans_handle *trans, struct btrfs_root *extent_root); static int del_pending_extents(struct btrfs_trans_handle *trans, struct btrfs_root *extent_root); -/* - * pending extents are blocks that we're trying to allocate in the extent - * map while trying to grow the map because of other allocations. To avoid - * recursing, they are tagged in the radix tree and cleaned up after - * other allocations are done. The pending tag is also used in the same - * manner for deletes. - */ -#define CTREE_EXTENT_PENDING_DEL 0 -#define CTREE_EXTENT_PINNED 1 static int inc_block_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 blocknr) @@ -104,24 +94,21 @@ int btrfs_inc_ref(struct btrfs_trans_handle *trans, struct btrfs_root *root, int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans, struct btrfs_root *root) { - struct buffer_head *gang[8]; + unsigned long gang[8]; u64 first = 0; int ret; int i; + struct radix_tree_root *pinned_radix = &root->fs_info->pinned_radix; while(1) { - ret = radix_tree_gang_lookup_tag(&root->fs_info->pinned_radix, - (void **)gang, 0, - ARRAY_SIZE(gang), - CTREE_EXTENT_PINNED); + ret = find_first_radix_bit(pinned_radix, gang, + ARRAY_SIZE(gang)); if (!ret) break; if (!first) - first = gang[0]->b_blocknr; + first = gang[0]; for (i = 0; i < ret; i++) { - radix_tree_delete(&root->fs_info->pinned_radix, - gang[i]->b_blocknr); - brelse(gang[i]); + clear_radix_bit(pinned_radix, gang[i]); } } if (root->fs_info->last_insert.objectid > first) @@ -161,29 +148,27 @@ static int finish_current_insert(struct btrfs_trans_handle *trans, struct return 0; } -static int pin_down_block(struct btrfs_root *root, u64 blocknr, int tag) +static int pin_down_block(struct btrfs_root *root, u64 blocknr, int pending) { int err; - struct buffer_head *bh = sb_getblk(root->fs_info->sb, blocknr); struct btrfs_header *header; - BUG_ON(!bh); - - header = btrfs_buffer_header(bh); - if (btrfs_header_generation(header) == - root->fs_info->running_transaction->transid) { - return 0; - } - - err = radix_tree_insert(&root->fs_info->pinned_radix, - blocknr, bh); - if (err && err != -EEXIST) { - BUG(); - return err; - } - if (err == -EEXIST) + struct buffer_head *bh; + + bh = sb_find_get_block(root->fs_info->sb, blocknr); + if (bh) { + header = btrfs_buffer_header(bh); + if (btrfs_header_generation(header) == + root->fs_info->running_transaction->transid) { + brelse(bh); + return 0; + } brelse(bh); - radix_tree_tag_set(&root->fs_info->pinned_radix, blocknr, - tag); + } + if (pending) + err = set_radix_bit(&root->fs_info->pending_del_radix, blocknr); + else + err = set_radix_bit(&root->fs_info->pinned_radix, blocknr); + BUG_ON(err); return 0; } @@ -225,8 +210,7 @@ static int __free_extent(struct btrfs_trans_handle *trans, struct btrfs_root u64 super_blocks_used; if (pin) { - ret = pin_down_block(root, blocknr, - CTREE_EXTENT_PINNED); + ret = pin_down_block(root, blocknr, 0); BUG_ON(ret); } @@ -255,25 +239,26 @@ static int del_pending_extents(struct btrfs_trans_handle *trans, struct int ret; int wret; int err = 0; - struct buffer_head *gang[4]; + unsigned long gang[4]; int i; - struct radix_tree_root *radix = &extent_root->fs_info->pinned_radix; + struct radix_tree_root *pending_radix; + struct radix_tree_root *pinned_radix; + + pending_radix = &extent_root->fs_info->pending_del_radix; + pinned_radix = &extent_root->fs_info->pinned_radix; while(1) { - ret = radix_tree_gang_lookup_tag( - &extent_root->fs_info->pinned_radix, - (void **)gang, 0, - ARRAY_SIZE(gang), - CTREE_EXTENT_PENDING_DEL); + ret = find_first_radix_bit(pending_radix, gang, + ARRAY_SIZE(gang)); if (!ret) break; for (i = 0; i < ret; i++) { - radix_tree_tag_set(radix, gang[i]->b_blocknr, - CTREE_EXTENT_PINNED); - radix_tree_tag_clear(radix, gang[i]->b_blocknr, - CTREE_EXTENT_PENDING_DEL); + wret = set_radix_bit(pinned_radix, gang[i]); + BUG_ON(wret); + wret = clear_radix_bit(pending_radix, gang[i]); + BUG_ON(wret); wret = __free_extent(trans, extent_root, - gang[i]->b_blocknr, 1, 0); + gang[i], 1, 0); if (wret) err = wret; } @@ -294,7 +279,7 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans, struct btrfs_root if (root == extent_root) { t = find_tree_block(root, blocknr); - pin_down_block(root, blocknr, CTREE_EXTENT_PENDING_DEL); + pin_down_block(root, blocknr, 1); return 0; } ret = __free_extent(trans, root, blocknr, num_blocks, pin); @@ -393,7 +378,7 @@ check_pending: BUG_ON(ins->objectid < search_start); for (test_block = ins->objectid; test_block < ins->objectid + total_needed; test_block++) { - if (radix_tree_lookup(&root->fs_info->pinned_radix, + if (test_radix_bit(&root->fs_info->pinned_radix, test_block)) { search_start = test_block + 1; goto check_failed; -- cgit v0.10.2