Update Linux to v5.10.109
Sourced from [1]
[1] https://cdn.kernel.org/pub/linux/kernel/v5.x/linux-5.10.109.tar.xz
Change-Id: I19bca9fc6762d4e63bcf3e4cba88bbe560d9c76c
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/fs/btrfs/delalloc-space.c b/fs/btrfs/delalloc-space.c
index f4f531c..bacee09 100644
--- a/fs/btrfs/delalloc-space.c
+++ b/fs/btrfs/delalloc-space.c
@@ -9,136 +9,127 @@
#include "qgroup.h"
#include "block-group.h"
+/*
+ * HOW DOES THIS WORK
+ *
+ * There are two stages to data reservations, one for data and one for metadata
+ * to handle the new extents and checksums generated by writing data.
+ *
+ *
+ * DATA RESERVATION
+ * The general flow of the data reservation is as follows
+ *
+ * -> Reserve
+ * We call into btrfs_reserve_data_bytes() for the user request bytes that
+ * they wish to write. We make this reservation and add it to
+ * space_info->bytes_may_use. We set EXTENT_DELALLOC on the inode io_tree
+ * for the range and carry on if this is buffered, or follow up trying to
+ * make a real allocation if we are pre-allocating or doing O_DIRECT.
+ *
+ * -> Use
+ * At writepages()/prealloc/O_DIRECT time we will call into
+ * btrfs_reserve_extent() for some part or all of this range of bytes. We
+ * will make the allocation and subtract space_info->bytes_may_use by the
+ * original requested length and increase the space_info->bytes_reserved by
+ * the allocated length. This distinction is important because compression
+ * may allocate a smaller on disk extent than we previously reserved.
+ *
+ * -> Allocation
+ * finish_ordered_io() will insert the new file extent item for this range,
+ * and then add a delayed ref update for the extent tree. Once that delayed
+ * ref is written the extent size is subtracted from
+ * space_info->bytes_reserved and added to space_info->bytes_used.
+ *
+ * Error handling
+ *
+ * -> By the reservation maker
+ * This is the simplest case, we haven't completed our operation and we know
+ * how much we reserved, we can simply call
+ * btrfs_free_reserved_data_space*() and it will be removed from
+ * space_info->bytes_may_use.
+ *
+ * -> After the reservation has been made, but before cow_file_range()
+ * This is specifically for the delalloc case. You must clear
+ * EXTENT_DELALLOC with the EXTENT_CLEAR_DATA_RESV bit, and the range will
+ * be subtracted from space_info->bytes_may_use.
+ *
+ * METADATA RESERVATION
+ * The general metadata reservation lifetimes are discussed elsewhere, this
+ * will just focus on how it is used for delalloc space.
+ *
+ * We keep track of two things on a per inode bases
+ *
+ * ->outstanding_extents
+ * This is the number of file extent items we'll need to handle all of the
+ * outstanding DELALLOC space we have in this inode. We limit the maximum
+ * size of an extent, so a large contiguous dirty area may require more than
+ * one outstanding_extent, which is why count_max_extents() is used to
+ * determine how many outstanding_extents get added.
+ *
+ * ->csum_bytes
+ * This is essentially how many dirty bytes we have for this inode, so we
+ * can calculate the number of checksum items we would have to add in order
+ * to checksum our outstanding data.
+ *
+ * We keep a per-inode block_rsv in order to make it easier to keep track of
+ * our reservation. We use btrfs_calculate_inode_block_rsv_size() to
+ * calculate the current theoretical maximum reservation we would need for the
+ * metadata for this inode. We call this and then adjust our reservation as
+ * necessary, either by attempting to reserve more space, or freeing up excess
+ * space.
+ *
+ * OUTSTANDING_EXTENTS HANDLING
+ *
+ * ->outstanding_extents is used for keeping track of how many extents we will
+ * need to use for this inode, and it will fluctuate depending on where you are
+ * in the life cycle of the dirty data. Consider the following normal case for
+ * a completely clean inode, with a num_bytes < our maximum allowed extent size
+ *
+ * -> reserve
+ * ->outstanding_extents += 1 (current value is 1)
+ *
+ * -> set_delalloc
+ * ->outstanding_extents += 1 (currrent value is 2)
+ *
+ * -> btrfs_delalloc_release_extents()
+ * ->outstanding_extents -= 1 (current value is 1)
+ *
+ * We must call this once we are done, as we hold our reservation for the
+ * duration of our operation, and then assume set_delalloc will update the
+ * counter appropriately.
+ *
+ * -> add ordered extent
+ * ->outstanding_extents += 1 (current value is 2)
+ *
+ * -> btrfs_clear_delalloc_extent
+ * ->outstanding_extents -= 1 (current value is 1)
+ *
+ * -> finish_ordered_io/btrfs_remove_ordered_extent
+ * ->outstanding_extents -= 1 (current value is 0)
+ *
+ * Each stage is responsible for their own accounting of the extent, thus
+ * making error handling and cleanup easier.
+ */
+
int btrfs_alloc_data_chunk_ondemand(struct btrfs_inode *inode, u64 bytes)
{
struct btrfs_root *root = inode->root;
struct btrfs_fs_info *fs_info = root->fs_info;
- struct btrfs_space_info *data_sinfo = fs_info->data_sinfo;
- u64 used;
- int ret = 0;
- int need_commit = 2;
- int have_pinned_space;
+ enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_FLUSH_DATA;
/* Make sure bytes are sectorsize aligned */
bytes = ALIGN(bytes, fs_info->sectorsize);
- if (btrfs_is_free_space_inode(inode)) {
- need_commit = 0;
- ASSERT(current->journal_info);
- }
+ if (btrfs_is_free_space_inode(inode))
+ flush = BTRFS_RESERVE_FLUSH_FREE_SPACE_INODE;
-again:
- /* Make sure we have enough space to handle the data first */
- spin_lock(&data_sinfo->lock);
- used = btrfs_space_info_used(data_sinfo, true);
-
- if (used + bytes > data_sinfo->total_bytes) {
- struct btrfs_trans_handle *trans;
-
- /*
- * If we don't have enough free bytes in this space then we need
- * to alloc a new chunk.
- */
- if (!data_sinfo->full) {
- u64 alloc_target;
-
- data_sinfo->force_alloc = CHUNK_ALLOC_FORCE;
- spin_unlock(&data_sinfo->lock);
-
- alloc_target = btrfs_data_alloc_profile(fs_info);
- /*
- * It is ugly that we don't call nolock join
- * transaction for the free space inode case here.
- * But it is safe because we only do the data space
- * reservation for the free space cache in the
- * transaction context, the common join transaction
- * just increase the counter of the current transaction
- * handler, doesn't try to acquire the trans_lock of
- * the fs.
- */
- trans = btrfs_join_transaction(root);
- if (IS_ERR(trans))
- return PTR_ERR(trans);
-
- ret = btrfs_chunk_alloc(trans, alloc_target,
- CHUNK_ALLOC_NO_FORCE);
- btrfs_end_transaction(trans);
- if (ret < 0) {
- if (ret != -ENOSPC)
- return ret;
- else {
- have_pinned_space = 1;
- goto commit_trans;
- }
- }
-
- goto again;
- }
-
- /*
- * If we don't have enough pinned space to deal with this
- * allocation, and no removed chunk in current transaction,
- * don't bother committing the transaction.
- */
- have_pinned_space = __percpu_counter_compare(
- &data_sinfo->total_bytes_pinned,
- used + bytes - data_sinfo->total_bytes,
- BTRFS_TOTAL_BYTES_PINNED_BATCH);
- spin_unlock(&data_sinfo->lock);
-
- /* Commit the current transaction and try again */
-commit_trans:
- if (need_commit) {
- need_commit--;
-
- if (need_commit > 0) {
- btrfs_start_delalloc_roots(fs_info, -1);
- btrfs_wait_ordered_roots(fs_info, U64_MAX, 0,
- (u64)-1);
- }
-
- trans = btrfs_join_transaction(root);
- if (IS_ERR(trans))
- return PTR_ERR(trans);
- if (have_pinned_space >= 0 ||
- test_bit(BTRFS_TRANS_HAVE_FREE_BGS,
- &trans->transaction->flags) ||
- need_commit > 0) {
- ret = btrfs_commit_transaction(trans);
- if (ret)
- return ret;
- /*
- * The cleaner kthread might still be doing iput
- * operations. Wait for it to finish so that
- * more space is released. We don't need to
- * explicitly run the delayed iputs here because
- * the commit_transaction would have woken up
- * the cleaner.
- */
- ret = btrfs_wait_on_delayed_iputs(fs_info);
- if (ret)
- return ret;
- goto again;
- } else {
- btrfs_end_transaction(trans);
- }
- }
-
- trace_btrfs_space_reservation(fs_info,
- "space_info:enospc",
- data_sinfo->flags, bytes, 1);
- return -ENOSPC;
- }
- btrfs_space_info_update_bytes_may_use(fs_info, data_sinfo, bytes);
- spin_unlock(&data_sinfo->lock);
-
- return 0;
+ return btrfs_reserve_data_bytes(fs_info, bytes, flush);
}
-int btrfs_check_data_free_space(struct inode *inode,
+int btrfs_check_data_free_space(struct btrfs_inode *inode,
struct extent_changeset **reserved, u64 start, u64 len)
{
- struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
+ struct btrfs_fs_info *fs_info = inode->root->fs_info;
int ret;
/* align the range */
@@ -146,14 +137,14 @@
round_down(start, fs_info->sectorsize);
start = round_down(start, fs_info->sectorsize);
- ret = btrfs_alloc_data_chunk_ondemand(BTRFS_I(inode), len);
+ ret = btrfs_alloc_data_chunk_ondemand(inode, len);
if (ret < 0)
return ret;
/* Use new btrfs_qgroup_reserve_data to reserve precious data space. */
- ret = btrfs_qgroup_reserve_data(BTRFS_I(inode), reserved, start, len);
+ ret = btrfs_qgroup_reserve_data(inode, reserved, start, len);
if (ret < 0)
- btrfs_free_reserved_data_space_noquota(inode, start, len);
+ btrfs_free_reserved_data_space_noquota(fs_info, len);
else
ret = 0;
return ret;
@@ -167,21 +158,15 @@
* which we can't sleep and is sure it won't affect qgroup reserved space.
* Like clear_bit_hook().
*/
-void btrfs_free_reserved_data_space_noquota(struct inode *inode, u64 start,
+void btrfs_free_reserved_data_space_noquota(struct btrfs_fs_info *fs_info,
u64 len)
{
- struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct btrfs_space_info *data_sinfo;
- /* Make sure the range is aligned to sectorsize */
- len = round_up(start + len, fs_info->sectorsize) -
- round_down(start, fs_info->sectorsize);
- start = round_down(start, fs_info->sectorsize);
+ ASSERT(IS_ALIGNED(len, fs_info->sectorsize));
data_sinfo = fs_info->data_sinfo;
- spin_lock(&data_sinfo->lock);
- btrfs_space_info_update_bytes_may_use(fs_info, data_sinfo, -len);
- spin_unlock(&data_sinfo->lock);
+ btrfs_space_info_free_bytes_may_use(fs_info, data_sinfo, len);
}
/*
@@ -191,17 +176,17 @@
* This one will handle the per-inode data rsv map for accurate reserved
* space framework.
*/
-void btrfs_free_reserved_data_space(struct inode *inode,
+void btrfs_free_reserved_data_space(struct btrfs_inode *inode,
struct extent_changeset *reserved, u64 start, u64 len)
{
- struct btrfs_root *root = BTRFS_I(inode)->root;
+ struct btrfs_fs_info *fs_info = inode->root->fs_info;
/* Make sure the range is aligned to sectorsize */
- len = round_up(start + len, root->fs_info->sectorsize) -
- round_down(start, root->fs_info->sectorsize);
- start = round_down(start, root->fs_info->sectorsize);
+ len = round_up(start + len, fs_info->sectorsize) -
+ round_down(start, fs_info->sectorsize);
+ start = round_down(start, fs_info->sectorsize);
- btrfs_free_reserved_data_space_noquota(inode, start, len);
+ btrfs_free_reserved_data_space_noquota(fs_info, len);
btrfs_qgroup_free_data(inode, reserved, start, len);
}
@@ -228,8 +213,8 @@
* are releasing 0 bytes, and then we'll just get the reservation over
* the size free'd.
*/
- released = __btrfs_block_rsv_release(fs_info, block_rsv, 0,
- &qgroup_to_release);
+ released = btrfs_block_rsv_release(fs_info, block_rsv, 0,
+ &qgroup_to_release);
if (released > 0)
trace_btrfs_space_reservation(fs_info, "delalloc",
btrfs_ino(inode), released, 0);
@@ -307,7 +292,6 @@
unsigned nr_extents;
enum btrfs_reserve_flush_enum flush = BTRFS_RESERVE_FLUSH_ALL;
int ret = 0;
- bool delalloc_lock = true;
/*
* If we are a free space inode we need to not flush since we will be in
@@ -320,7 +304,6 @@
*/
if (btrfs_is_free_space_inode(inode)) {
flush = BTRFS_RESERVE_NO_FLUSH;
- delalloc_lock = false;
} else {
if (current->journal_info)
flush = BTRFS_RESERVE_FLUSH_LIMIT;
@@ -329,9 +312,6 @@
schedule_timeout(1);
}
- if (delalloc_lock)
- mutex_lock(&inode->delalloc_mutex);
-
num_bytes = ALIGN(num_bytes, fs_info->sectorsize);
/*
@@ -348,10 +328,12 @@
&qgroup_reserve);
ret = btrfs_qgroup_reserve_meta_prealloc(root, qgroup_reserve, true);
if (ret)
- goto out_fail;
+ return ret;
ret = btrfs_reserve_metadata_bytes(root, block_rsv, meta_reserve, flush);
- if (ret)
- goto out_qgroup;
+ if (ret) {
+ btrfs_qgroup_free_meta_prealloc(root, qgroup_reserve);
+ return ret;
+ }
/*
* Now we need to update our outstanding extents and csum bytes _first_
@@ -375,15 +357,7 @@
block_rsv->qgroup_rsv_reserved += qgroup_reserve;
spin_unlock(&block_rsv->lock);
- if (delalloc_lock)
- mutex_unlock(&inode->delalloc_mutex);
return 0;
-out_qgroup:
- btrfs_qgroup_free_meta_prealloc(root, qgroup_reserve);
-out_fail:
- if (delalloc_lock)
- mutex_unlock(&inode->delalloc_mutex);
- return ret;
}
/**
@@ -466,7 +440,7 @@
* Return 0 for success
* Return <0 for error(-ENOSPC or -EQUOT)
*/
-int btrfs_delalloc_reserve_space(struct inode *inode,
+int btrfs_delalloc_reserve_space(struct btrfs_inode *inode,
struct extent_changeset **reserved, u64 start, u64 len)
{
int ret;
@@ -474,7 +448,7 @@
ret = btrfs_check_data_free_space(inode, reserved, start, len);
if (ret < 0)
return ret;
- ret = btrfs_delalloc_reserve_metadata(BTRFS_I(inode), len);
+ ret = btrfs_delalloc_reserve_metadata(inode, len);
if (ret < 0)
btrfs_free_reserved_data_space(inode, *reserved, start, len);
return ret;
@@ -492,10 +466,10 @@
* list if there are no delalloc bytes left.
* Also it will handle the qgroup reserved space.
*/
-void btrfs_delalloc_release_space(struct inode *inode,
+void btrfs_delalloc_release_space(struct btrfs_inode *inode,
struct extent_changeset *reserved,
u64 start, u64 len, bool qgroup_free)
{
- btrfs_delalloc_release_metadata(BTRFS_I(inode), len, qgroup_free);
+ btrfs_delalloc_release_metadata(inode, len, qgroup_free);
btrfs_free_reserved_data_space(inode, reserved, start, len);
}