Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/fs/btrfs/block-rsv.c b/fs/btrfs/block-rsv.c
new file mode 100644
index 0000000..d07bd41
--- /dev/null
+++ b/fs/btrfs/block-rsv.c
@@ -0,0 +1,437 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include "misc.h"
+#include "ctree.h"
+#include "block-rsv.h"
+#include "space-info.h"
+#include "transaction.h"
+
+static u64 block_rsv_release_bytes(struct btrfs_fs_info *fs_info,
+ struct btrfs_block_rsv *block_rsv,
+ struct btrfs_block_rsv *dest, u64 num_bytes,
+ u64 *qgroup_to_release_ret)
+{
+ struct btrfs_space_info *space_info = block_rsv->space_info;
+ u64 qgroup_to_release = 0;
+ u64 ret;
+
+ spin_lock(&block_rsv->lock);
+ if (num_bytes == (u64)-1) {
+ num_bytes = block_rsv->size;
+ qgroup_to_release = block_rsv->qgroup_rsv_size;
+ }
+ block_rsv->size -= num_bytes;
+ if (block_rsv->reserved >= block_rsv->size) {
+ num_bytes = block_rsv->reserved - block_rsv->size;
+ block_rsv->reserved = block_rsv->size;
+ block_rsv->full = 1;
+ } else {
+ num_bytes = 0;
+ }
+ if (block_rsv->qgroup_rsv_reserved >= block_rsv->qgroup_rsv_size) {
+ qgroup_to_release = block_rsv->qgroup_rsv_reserved -
+ block_rsv->qgroup_rsv_size;
+ block_rsv->qgroup_rsv_reserved = block_rsv->qgroup_rsv_size;
+ } else {
+ qgroup_to_release = 0;
+ }
+ spin_unlock(&block_rsv->lock);
+
+ ret = num_bytes;
+ if (num_bytes > 0) {
+ if (dest) {
+ spin_lock(&dest->lock);
+ if (!dest->full) {
+ u64 bytes_to_add;
+
+ bytes_to_add = dest->size - dest->reserved;
+ bytes_to_add = min(num_bytes, bytes_to_add);
+ dest->reserved += bytes_to_add;
+ if (dest->reserved >= dest->size)
+ dest->full = 1;
+ num_bytes -= bytes_to_add;
+ }
+ spin_unlock(&dest->lock);
+ }
+ if (num_bytes)
+ btrfs_space_info_free_bytes_may_use(fs_info,
+ space_info,
+ num_bytes);
+ }
+ if (qgroup_to_release_ret)
+ *qgroup_to_release_ret = qgroup_to_release;
+ return ret;
+}
+
+int btrfs_block_rsv_migrate(struct btrfs_block_rsv *src,
+ struct btrfs_block_rsv *dst, u64 num_bytes,
+ bool update_size)
+{
+ int ret;
+
+ ret = btrfs_block_rsv_use_bytes(src, num_bytes);
+ if (ret)
+ return ret;
+
+ btrfs_block_rsv_add_bytes(dst, num_bytes, update_size);
+ return 0;
+}
+
+void btrfs_init_block_rsv(struct btrfs_block_rsv *rsv, unsigned short type)
+{
+ memset(rsv, 0, sizeof(*rsv));
+ spin_lock_init(&rsv->lock);
+ rsv->type = type;
+}
+
+void btrfs_init_metadata_block_rsv(struct btrfs_fs_info *fs_info,
+ struct btrfs_block_rsv *rsv,
+ unsigned short type)
+{
+ btrfs_init_block_rsv(rsv, type);
+ rsv->space_info = btrfs_find_space_info(fs_info,
+ BTRFS_BLOCK_GROUP_METADATA);
+}
+
+struct btrfs_block_rsv *btrfs_alloc_block_rsv(struct btrfs_fs_info *fs_info,
+ unsigned short type)
+{
+ struct btrfs_block_rsv *block_rsv;
+
+ block_rsv = kmalloc(sizeof(*block_rsv), GFP_NOFS);
+ if (!block_rsv)
+ return NULL;
+
+ btrfs_init_metadata_block_rsv(fs_info, block_rsv, type);
+ return block_rsv;
+}
+
+void btrfs_free_block_rsv(struct btrfs_fs_info *fs_info,
+ struct btrfs_block_rsv *rsv)
+{
+ if (!rsv)
+ return;
+ btrfs_block_rsv_release(fs_info, rsv, (u64)-1);
+ kfree(rsv);
+}
+
+int btrfs_block_rsv_add(struct btrfs_root *root,
+ struct btrfs_block_rsv *block_rsv, u64 num_bytes,
+ enum btrfs_reserve_flush_enum flush)
+{
+ int ret;
+
+ if (num_bytes == 0)
+ return 0;
+
+ ret = btrfs_reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
+ if (!ret)
+ btrfs_block_rsv_add_bytes(block_rsv, num_bytes, true);
+
+ return ret;
+}
+
+int btrfs_block_rsv_check(struct btrfs_block_rsv *block_rsv, int min_factor)
+{
+ u64 num_bytes = 0;
+ int ret = -ENOSPC;
+
+ if (!block_rsv)
+ return 0;
+
+ spin_lock(&block_rsv->lock);
+ num_bytes = div_factor(block_rsv->size, min_factor);
+ if (block_rsv->reserved >= num_bytes)
+ ret = 0;
+ spin_unlock(&block_rsv->lock);
+
+ return ret;
+}
+
+int btrfs_block_rsv_refill(struct btrfs_root *root,
+ struct btrfs_block_rsv *block_rsv, u64 min_reserved,
+ enum btrfs_reserve_flush_enum flush)
+{
+ u64 num_bytes = 0;
+ int ret = -ENOSPC;
+
+ if (!block_rsv)
+ return 0;
+
+ spin_lock(&block_rsv->lock);
+ num_bytes = min_reserved;
+ if (block_rsv->reserved >= num_bytes)
+ ret = 0;
+ else
+ num_bytes -= block_rsv->reserved;
+ spin_unlock(&block_rsv->lock);
+
+ if (!ret)
+ return 0;
+
+ ret = btrfs_reserve_metadata_bytes(root, block_rsv, num_bytes, flush);
+ if (!ret) {
+ btrfs_block_rsv_add_bytes(block_rsv, num_bytes, false);
+ return 0;
+ }
+
+ return ret;
+}
+
+u64 __btrfs_block_rsv_release(struct btrfs_fs_info *fs_info,
+ struct btrfs_block_rsv *block_rsv,
+ u64 num_bytes, u64 *qgroup_to_release)
+{
+ struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
+ struct btrfs_block_rsv *delayed_rsv = &fs_info->delayed_refs_rsv;
+ struct btrfs_block_rsv *target = NULL;
+
+ /*
+ * If we are the delayed_rsv then push to the global rsv, otherwise dump
+ * into the delayed rsv if it is not full.
+ */
+ if (block_rsv == delayed_rsv)
+ target = global_rsv;
+ else if (block_rsv != global_rsv && !delayed_rsv->full)
+ target = delayed_rsv;
+
+ if (target && block_rsv->space_info != target->space_info)
+ target = NULL;
+
+ return block_rsv_release_bytes(fs_info, block_rsv, target, num_bytes,
+ qgroup_to_release);
+}
+
+int btrfs_block_rsv_use_bytes(struct btrfs_block_rsv *block_rsv, u64 num_bytes)
+{
+ int ret = -ENOSPC;
+
+ spin_lock(&block_rsv->lock);
+ if (block_rsv->reserved >= num_bytes) {
+ block_rsv->reserved -= num_bytes;
+ if (block_rsv->reserved < block_rsv->size)
+ block_rsv->full = 0;
+ ret = 0;
+ }
+ spin_unlock(&block_rsv->lock);
+ return ret;
+}
+
+void btrfs_block_rsv_add_bytes(struct btrfs_block_rsv *block_rsv,
+ u64 num_bytes, bool update_size)
+{
+ spin_lock(&block_rsv->lock);
+ block_rsv->reserved += num_bytes;
+ if (update_size)
+ block_rsv->size += num_bytes;
+ else if (block_rsv->reserved >= block_rsv->size)
+ block_rsv->full = 1;
+ spin_unlock(&block_rsv->lock);
+}
+
+int btrfs_cond_migrate_bytes(struct btrfs_fs_info *fs_info,
+ struct btrfs_block_rsv *dest, u64 num_bytes,
+ int min_factor)
+{
+ struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
+ u64 min_bytes;
+
+ if (global_rsv->space_info != dest->space_info)
+ return -ENOSPC;
+
+ spin_lock(&global_rsv->lock);
+ min_bytes = div_factor(global_rsv->size, min_factor);
+ if (global_rsv->reserved < min_bytes + num_bytes) {
+ spin_unlock(&global_rsv->lock);
+ return -ENOSPC;
+ }
+ global_rsv->reserved -= num_bytes;
+ if (global_rsv->reserved < global_rsv->size)
+ global_rsv->full = 0;
+ spin_unlock(&global_rsv->lock);
+
+ btrfs_block_rsv_add_bytes(dest, num_bytes, true);
+ return 0;
+}
+
+void btrfs_update_global_block_rsv(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_block_rsv *block_rsv = &fs_info->global_block_rsv;
+ struct btrfs_space_info *sinfo = block_rsv->space_info;
+ u64 num_bytes;
+ unsigned min_items;
+
+ /*
+ * The global block rsv is based on the size of the extent tree, the
+ * checksum tree and the root tree. If the fs is empty we want to set
+ * it to a minimal amount for safety.
+ */
+ num_bytes = btrfs_root_used(&fs_info->extent_root->root_item) +
+ btrfs_root_used(&fs_info->csum_root->root_item) +
+ btrfs_root_used(&fs_info->tree_root->root_item);
+
+ /*
+ * We at a minimum are going to modify the csum root, the tree root, and
+ * the extent root.
+ */
+ min_items = 3;
+
+ /*
+ * But we also want to reserve enough space so we can do the fallback
+ * global reserve for an unlink, which is an additional 5 items (see the
+ * comment in __unlink_start_trans for what we're modifying.)
+ *
+ * But we also need space for the delayed ref updates from the unlink,
+ * so its 10, 5 for the actual operation, and 5 for the delayed ref
+ * updates.
+ */
+ min_items += 10;
+
+ num_bytes = max_t(u64, num_bytes,
+ btrfs_calc_insert_metadata_size(fs_info, min_items));
+
+ spin_lock(&sinfo->lock);
+ spin_lock(&block_rsv->lock);
+
+ block_rsv->size = min_t(u64, num_bytes, SZ_512M);
+
+ if (block_rsv->reserved < block_rsv->size) {
+ num_bytes = block_rsv->size - block_rsv->reserved;
+ block_rsv->reserved += num_bytes;
+ btrfs_space_info_update_bytes_may_use(fs_info, sinfo,
+ num_bytes);
+ } else if (block_rsv->reserved > block_rsv->size) {
+ num_bytes = block_rsv->reserved - block_rsv->size;
+ btrfs_space_info_update_bytes_may_use(fs_info, sinfo,
+ -num_bytes);
+ block_rsv->reserved = block_rsv->size;
+ btrfs_try_granting_tickets(fs_info, sinfo);
+ }
+
+ if (block_rsv->reserved == block_rsv->size)
+ block_rsv->full = 1;
+ else
+ block_rsv->full = 0;
+
+ spin_unlock(&block_rsv->lock);
+ spin_unlock(&sinfo->lock);
+}
+
+void btrfs_init_global_block_rsv(struct btrfs_fs_info *fs_info)
+{
+ struct btrfs_space_info *space_info;
+
+ space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM);
+ fs_info->chunk_block_rsv.space_info = space_info;
+
+ space_info = btrfs_find_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA);
+ fs_info->global_block_rsv.space_info = space_info;
+ fs_info->trans_block_rsv.space_info = space_info;
+ fs_info->empty_block_rsv.space_info = space_info;
+ fs_info->delayed_block_rsv.space_info = space_info;
+ fs_info->delayed_refs_rsv.space_info = space_info;
+
+ fs_info->extent_root->block_rsv = &fs_info->delayed_refs_rsv;
+ fs_info->csum_root->block_rsv = &fs_info->delayed_refs_rsv;
+ fs_info->dev_root->block_rsv = &fs_info->global_block_rsv;
+ fs_info->tree_root->block_rsv = &fs_info->global_block_rsv;
+ if (fs_info->quota_root)
+ fs_info->quota_root->block_rsv = &fs_info->global_block_rsv;
+ fs_info->chunk_root->block_rsv = &fs_info->chunk_block_rsv;
+
+ btrfs_update_global_block_rsv(fs_info);
+}
+
+void btrfs_release_global_block_rsv(struct btrfs_fs_info *fs_info)
+{
+ btrfs_block_rsv_release(fs_info, &fs_info->global_block_rsv, (u64)-1);
+ WARN_ON(fs_info->trans_block_rsv.size > 0);
+ WARN_ON(fs_info->trans_block_rsv.reserved > 0);
+ WARN_ON(fs_info->chunk_block_rsv.size > 0);
+ WARN_ON(fs_info->chunk_block_rsv.reserved > 0);
+ WARN_ON(fs_info->delayed_block_rsv.size > 0);
+ WARN_ON(fs_info->delayed_block_rsv.reserved > 0);
+ WARN_ON(fs_info->delayed_refs_rsv.reserved > 0);
+ WARN_ON(fs_info->delayed_refs_rsv.size > 0);
+}
+
+static struct btrfs_block_rsv *get_block_rsv(
+ const struct btrfs_trans_handle *trans,
+ const struct btrfs_root *root)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_block_rsv *block_rsv = NULL;
+
+ if (test_bit(BTRFS_ROOT_REF_COWS, &root->state) ||
+ (root == fs_info->csum_root && trans->adding_csums) ||
+ (root == fs_info->uuid_root))
+ block_rsv = trans->block_rsv;
+
+ if (!block_rsv)
+ block_rsv = root->block_rsv;
+
+ if (!block_rsv)
+ block_rsv = &fs_info->empty_block_rsv;
+
+ return block_rsv;
+}
+
+struct btrfs_block_rsv *btrfs_use_block_rsv(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ u32 blocksize)
+{
+ struct btrfs_fs_info *fs_info = root->fs_info;
+ struct btrfs_block_rsv *block_rsv;
+ struct btrfs_block_rsv *global_rsv = &fs_info->global_block_rsv;
+ int ret;
+ bool global_updated = false;
+
+ block_rsv = get_block_rsv(trans, root);
+
+ if (unlikely(block_rsv->size == 0))
+ goto try_reserve;
+again:
+ ret = btrfs_block_rsv_use_bytes(block_rsv, blocksize);
+ if (!ret)
+ return block_rsv;
+
+ if (block_rsv->failfast)
+ return ERR_PTR(ret);
+
+ if (block_rsv->type == BTRFS_BLOCK_RSV_GLOBAL && !global_updated) {
+ global_updated = true;
+ btrfs_update_global_block_rsv(fs_info);
+ goto again;
+ }
+
+ /*
+ * The global reserve still exists to save us from ourselves, so don't
+ * warn_on if we are short on our delayed refs reserve.
+ */
+ if (block_rsv->type != BTRFS_BLOCK_RSV_DELREFS &&
+ btrfs_test_opt(fs_info, ENOSPC_DEBUG)) {
+ static DEFINE_RATELIMIT_STATE(_rs,
+ DEFAULT_RATELIMIT_INTERVAL * 10,
+ /*DEFAULT_RATELIMIT_BURST*/ 1);
+ if (__ratelimit(&_rs))
+ WARN(1, KERN_DEBUG
+ "BTRFS: block rsv returned %d\n", ret);
+ }
+try_reserve:
+ ret = btrfs_reserve_metadata_bytes(root, block_rsv, blocksize,
+ BTRFS_RESERVE_NO_FLUSH);
+ if (!ret)
+ return block_rsv;
+ /*
+ * If we couldn't reserve metadata bytes try and use some from
+ * the global reserve if its space type is the same as the global
+ * reservation.
+ */
+ if (block_rsv->type != BTRFS_BLOCK_RSV_GLOBAL &&
+ block_rsv->space_info == global_rsv->space_info) {
+ ret = btrfs_block_rsv_use_bytes(global_rsv, blocksize);
+ if (!ret)
+ return global_rsv;
+ }
+ return ERR_PTR(ret);
+}