@@ -82,6 +82,28 @@ struct extent_state {
#endif
};
+/*
+ * Extra options for extent io tree operations.
+ *
+ * All of these options are initialized to 0/false/NULL by default,
+ * and most callers should utilize the wrappers other than the extra options.
+ */
+struct extent_io_extra_options {
+ /*
+ * For __set_extent_bit(), to return -EEXIST when hit an extent with
+ * @excl_bits set, and update @excl_failed_start.
+ * Utizlied by EXTENT_LOCKED wrappers.
+ */
+ u32 excl_bits;
+ u64 excl_failed_start;
+
+ /*
+ * For __set/__clear_extent_bit() to record how many bytes is modified.
+ * For qgroup related functions.
+ */
+ struct extent_changeset *changeset;
+};
+
int __init extent_state_cache_init(void);
void __cold extent_state_cache_exit(void);
@@ -29,6 +29,7 @@ static struct kmem_cache *extent_state_cache;
static struct kmem_cache *extent_buffer_cache;
static struct bio_set btrfs_bioset;
+static struct extent_io_extra_options default_opts = { 0 };
static inline bool extent_state_in_tree(const struct extent_state *state)
{
return !RB_EMPTY_NODE(&state->rb_node);
@@ -952,10 +953,10 @@ static void cache_state(struct extent_state *state,
}
/*
- * set some bits on a range in the tree. This may require allocations or
+ * Set some bits on a range in the tree. This may require allocations or
* sleeping, so the gfp mask is used to indicate what is allowed.
*
- * If any of the exclusive bits are set, this will fail with -EEXIST if some
+ * If *any* of the exclusive bits are set, this will fail with -EEXIST if some
* part of the range already has the desired bits set. The start of the
* existing range is returned in failed_start in this case.
*
@@ -964,26 +965,30 @@ static void cache_state(struct extent_state *state,
static int __must_check
__set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
- unsigned bits, unsigned exclusive_bits,
- u64 *failed_start, struct extent_state **cached_state,
- gfp_t mask, struct extent_changeset *changeset)
+ unsigned bits, struct extent_state **cached_state,
+ gfp_t mask, struct extent_io_extra_options *extra_opts)
{
struct extent_state *state;
struct extent_state *prealloc = NULL;
struct rb_node *node;
struct rb_node **p;
struct rb_node *parent;
+ struct extent_changeset *changeset;
int err = 0;
+ u32 exclusive_bits;
+ u64 *failed_start;
u64 last_start;
u64 last_end;
btrfs_debug_check_extent_io_range(tree, start, end);
trace_btrfs_set_extent_bit(tree, start, end - start + 1, bits);
- if (exclusive_bits)
- ASSERT(failed_start);
- else
- ASSERT(!failed_start);
+ if (!extra_opts)
+ extra_opts = &default_opts;
+ exclusive_bits = extra_opts->excl_bits;
+ failed_start = &extra_opts->excl_failed_start;
+ changeset = extra_opts->changeset;
+
again:
if (!prealloc && gfpflags_allow_blocking(mask)) {
/*
@@ -1187,7 +1192,7 @@ int set_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
unsigned bits, struct extent_state **cached_state,
gfp_t mask)
{
- return __set_extent_bit(tree, start, end, bits, 0, NULL, cached_state,
+ return __set_extent_bit(tree, start, end, bits, cached_state,
mask, NULL);
}
@@ -1414,6 +1419,10 @@ int convert_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
int set_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
unsigned bits, struct extent_changeset *changeset)
{
+ struct extent_io_extra_options extra_opts = {
+ .changeset = changeset,
+ };
+
/*
* We don't support EXTENT_LOCKED yet, as current changeset will
* record any bits changed, so for EXTENT_LOCKED case, it will
@@ -1422,15 +1431,14 @@ int set_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
*/
BUG_ON(bits & EXTENT_LOCKED);
- return __set_extent_bit(tree, start, end, bits, 0, NULL, NULL, GFP_NOFS,
- changeset);
+ return __set_extent_bit(tree, start, end, bits, NULL, GFP_NOFS,
+ &extra_opts);
}
int set_extent_bits_nowait(struct extent_io_tree *tree, u64 start, u64 end,
unsigned bits)
{
- return __set_extent_bit(tree, start, end, bits, 0, NULL, NULL,
- GFP_NOWAIT, NULL);
+ return __set_extent_bit(tree, start, end, bits, NULL, GFP_NOWAIT, NULL);
}
int clear_extent_bit(struct extent_io_tree *tree, u64 start, u64 end,
@@ -1461,16 +1469,18 @@ int clear_record_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
struct extent_state **cached_state)
{
+ struct extent_io_extra_options extra_opts = {
+ .excl_bits = EXTENT_LOCKED,
+ };
int err;
- u64 failed_start;
while (1) {
err = __set_extent_bit(tree, start, end, EXTENT_LOCKED,
- EXTENT_LOCKED, &failed_start,
- cached_state, GFP_NOFS, NULL);
+ cached_state, GFP_NOFS, &extra_opts);
if (err == -EEXIST) {
- wait_extent_bit(tree, failed_start, end, EXTENT_LOCKED);
- start = failed_start;
+ wait_extent_bit(tree, extra_opts.excl_failed_start, end,
+ EXTENT_LOCKED);
+ start = extra_opts.excl_failed_start;
} else
break;
WARN_ON(start > end);
@@ -1480,14 +1490,17 @@ int lock_extent_bits(struct extent_io_tree *tree, u64 start, u64 end,
int try_lock_extent(struct extent_io_tree *tree, u64 start, u64 end)
{
+ struct extent_io_extra_options extra_opts = {
+ .excl_bits = EXTENT_LOCKED,
+ };
int err;
- u64 failed_start;
- err = __set_extent_bit(tree, start, end, EXTENT_LOCKED, EXTENT_LOCKED,
- &failed_start, NULL, GFP_NOFS, NULL);
+ err = __set_extent_bit(tree, start, end, EXTENT_LOCKED,
+ NULL, GFP_NOFS, &extra_opts);
if (err == -EEXIST) {
- if (failed_start > start)
- clear_extent_bit(tree, start, failed_start - 1,
+ if (extra_opts.excl_failed_start > start)
+ clear_extent_bit(tree, start,
+ extra_opts.excl_failed_start - 1,
EXTENT_LOCKED, 1, 0, NULL);
return 0;
}
For __set_extent_bit(), those parameter are less common for most callers: - exclusive_bits - failed_start Paired together for EXTENT_LOCKED usage. - extent_changeset For qgroup usage. As a common design principle, less common parameters should have their default values and only callers really need them will set the parameters to non-default values. Sink those parameters into a new structure, extent_io_extra_options. So most callers won't bother those less used parameters, and make later expansion easier. Signed-off-by: Qu Wenruo <wqu@suse.com> --- fs/btrfs/extent-io-tree.h | 22 ++++++++++++++ fs/btrfs/extent_io.c | 61 ++++++++++++++++++++++++--------------- 2 files changed, 59 insertions(+), 24 deletions(-)