Btrfs: Make free space cache code generic
So we can re-use the code to cache free inode numbers.
The change is quite straightforward. Two new structures are introduced.
- struct btrfs_free_space_ctl
We move those variables that are used for caching free space from
struct btrfs_block_group_cache to this new struct.
- struct btrfs_free_space_op
We do block group specific work (e.g. calculation of extents threshold)
through functions registered in this struct.
And then we can remove references to struct btrfs_block_group_cache.
Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c
index 0e23bba..d4fb4f0 100644
--- a/fs/btrfs/free-space-cache.c
+++ b/fs/btrfs/free-space-cache.c
@@ -29,9 +29,7 @@
#define BITS_PER_BITMAP (PAGE_CACHE_SIZE * 8)
#define MAX_CACHE_BYTES_PER_GIG (32 * 1024)
-static void recalculate_thresholds(struct btrfs_block_group_cache
- *block_group);
-static int link_free_space(struct btrfs_block_group_cache *block_group,
+static int link_free_space(struct btrfs_free_space_ctl *ctl,
struct btrfs_free_space *info);
struct inode *lookup_free_space_inode(struct btrfs_root *root,
@@ -212,6 +210,7 @@
int load_free_space_cache(struct btrfs_fs_info *fs_info,
struct btrfs_block_group_cache *block_group)
{
+ struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
struct btrfs_root *root = fs_info->tree_root;
struct inode *inode;
struct btrfs_free_space_header *header;
@@ -417,9 +416,9 @@
}
if (entry->type == BTRFS_FREE_SPACE_EXTENT) {
- spin_lock(&block_group->tree_lock);
- ret = link_free_space(block_group, e);
- spin_unlock(&block_group->tree_lock);
+ spin_lock(&ctl->tree_lock);
+ ret = link_free_space(ctl, e);
+ spin_unlock(&ctl->tree_lock);
BUG_ON(ret);
} else {
e->bitmap = kzalloc(PAGE_CACHE_SIZE, GFP_NOFS);
@@ -431,11 +430,11 @@
page_cache_release(page);
goto free_cache;
}
- spin_lock(&block_group->tree_lock);
- ret = link_free_space(block_group, e);
- block_group->total_bitmaps++;
- recalculate_thresholds(block_group);
- spin_unlock(&block_group->tree_lock);
+ spin_lock(&ctl->tree_lock);
+ ret = link_free_space(ctl, e);
+ ctl->total_bitmaps++;
+ ctl->op->recalc_thresholds(ctl);
+ spin_unlock(&ctl->tree_lock);
list_add_tail(&e->list, &bitmaps);
}
@@ -471,16 +470,16 @@
index++;
}
- spin_lock(&block_group->tree_lock);
- if (block_group->free_space != (block_group->key.offset - used -
- block_group->bytes_super)) {
- spin_unlock(&block_group->tree_lock);
+ spin_lock(&ctl->tree_lock);
+ if (ctl->free_space != (block_group->key.offset - used -
+ block_group->bytes_super)) {
+ spin_unlock(&ctl->tree_lock);
printk(KERN_ERR "block group %llu has an wrong amount of free "
"space\n", block_group->key.objectid);
ret = 0;
goto free_cache;
}
- spin_unlock(&block_group->tree_lock);
+ spin_unlock(&ctl->tree_lock);
ret = 1;
out:
@@ -503,6 +502,7 @@
struct btrfs_block_group_cache *block_group,
struct btrfs_path *path)
{
+ struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
struct btrfs_free_space_header *header;
struct extent_buffer *leaf;
struct inode *inode;
@@ -546,7 +546,7 @@
return 0;
}
- node = rb_first(&block_group->free_space_offset);
+ node = rb_first(&ctl->free_space_offset);
if (!node) {
iput(inode);
return 0;
@@ -851,30 +851,30 @@
return ret;
}
-static inline unsigned long offset_to_bit(u64 bitmap_start, u64 sectorsize,
+static inline unsigned long offset_to_bit(u64 bitmap_start, u32 unit,
u64 offset)
{
BUG_ON(offset < bitmap_start);
offset -= bitmap_start;
- return (unsigned long)(div64_u64(offset, sectorsize));
+ return (unsigned long)(div_u64(offset, unit));
}
-static inline unsigned long bytes_to_bits(u64 bytes, u64 sectorsize)
+static inline unsigned long bytes_to_bits(u64 bytes, u32 unit)
{
- return (unsigned long)(div64_u64(bytes, sectorsize));
+ return (unsigned long)(div_u64(bytes, unit));
}
-static inline u64 offset_to_bitmap(struct btrfs_block_group_cache *block_group,
+static inline u64 offset_to_bitmap(struct btrfs_free_space_ctl *ctl,
u64 offset)
{
u64 bitmap_start;
u64 bytes_per_bitmap;
- bytes_per_bitmap = BITS_PER_BITMAP * block_group->sectorsize;
- bitmap_start = offset - block_group->key.objectid;
+ bytes_per_bitmap = BITS_PER_BITMAP * ctl->unit;
+ bitmap_start = offset - ctl->start;
bitmap_start = div64_u64(bitmap_start, bytes_per_bitmap);
bitmap_start *= bytes_per_bitmap;
- bitmap_start += block_group->key.objectid;
+ bitmap_start += ctl->start;
return bitmap_start;
}
@@ -932,10 +932,10 @@
* offset.
*/
static struct btrfs_free_space *
-tree_search_offset(struct btrfs_block_group_cache *block_group,
+tree_search_offset(struct btrfs_free_space_ctl *ctl,
u64 offset, int bitmap_only, int fuzzy)
{
- struct rb_node *n = block_group->free_space_offset.rb_node;
+ struct rb_node *n = ctl->free_space_offset.rb_node;
struct btrfs_free_space *entry, *prev = NULL;
/* find entry that is closest to the 'offset' */
@@ -1031,8 +1031,7 @@
break;
}
}
- if (entry->offset + BITS_PER_BITMAP *
- block_group->sectorsize > offset)
+ if (entry->offset + BITS_PER_BITMAP * ctl->unit > offset)
return entry;
} else if (entry->offset + entry->bytes > offset)
return entry;
@@ -1043,7 +1042,7 @@
while (1) {
if (entry->bitmap) {
if (entry->offset + BITS_PER_BITMAP *
- block_group->sectorsize > offset)
+ ctl->unit > offset)
break;
} else {
if (entry->offset + entry->bytes > offset)
@@ -1059,42 +1058,47 @@
}
static inline void
-__unlink_free_space(struct btrfs_block_group_cache *block_group,
+__unlink_free_space(struct btrfs_free_space_ctl *ctl,
struct btrfs_free_space *info)
{
- rb_erase(&info->offset_index, &block_group->free_space_offset);
- block_group->free_extents--;
+ rb_erase(&info->offset_index, &ctl->free_space_offset);
+ ctl->free_extents--;
}
-static void unlink_free_space(struct btrfs_block_group_cache *block_group,
+static void unlink_free_space(struct btrfs_free_space_ctl *ctl,
struct btrfs_free_space *info)
{
- __unlink_free_space(block_group, info);
- block_group->free_space -= info->bytes;
+ __unlink_free_space(ctl, info);
+ ctl->free_space -= info->bytes;
}
-static int link_free_space(struct btrfs_block_group_cache *block_group,
+static int link_free_space(struct btrfs_free_space_ctl *ctl,
struct btrfs_free_space *info)
{
int ret = 0;
BUG_ON(!info->bitmap && !info->bytes);
- ret = tree_insert_offset(&block_group->free_space_offset, info->offset,
+ ret = tree_insert_offset(&ctl->free_space_offset, info->offset,
&info->offset_index, (info->bitmap != NULL));
if (ret)
return ret;
- block_group->free_space += info->bytes;
- block_group->free_extents++;
+ ctl->free_space += info->bytes;
+ ctl->free_extents++;
return ret;
}
-static void recalculate_thresholds(struct btrfs_block_group_cache *block_group)
+static void recalculate_thresholds(struct btrfs_free_space_ctl *ctl)
{
+ struct btrfs_block_group_cache *block_group = ctl->private;
u64 max_bytes;
u64 bitmap_bytes;
u64 extent_bytes;
u64 size = block_group->key.offset;
+ u64 bytes_per_bg = BITS_PER_BITMAP * block_group->sectorsize;
+ int max_bitmaps = div64_u64(size + bytes_per_bg - 1, bytes_per_bg);
+
+ BUG_ON(ctl->total_bitmaps > max_bitmaps);
/*
* The goal is to keep the total amount of memory used per 1gb of space
@@ -1112,10 +1116,10 @@
* sure we don't go over our overall goal of MAX_CACHE_BYTES_PER_GIG as
* we add more bitmaps.
*/
- bitmap_bytes = (block_group->total_bitmaps + 1) * PAGE_CACHE_SIZE;
+ bitmap_bytes = (ctl->total_bitmaps + 1) * PAGE_CACHE_SIZE;
if (bitmap_bytes >= max_bytes) {
- block_group->extents_thresh = 0;
+ ctl->extents_thresh = 0;
return;
}
@@ -1126,43 +1130,43 @@
extent_bytes = max_bytes - bitmap_bytes;
extent_bytes = min_t(u64, extent_bytes, div64_u64(max_bytes, 2));
- block_group->extents_thresh =
+ ctl->extents_thresh =
div64_u64(extent_bytes, (sizeof(struct btrfs_free_space)));
}
-static void bitmap_clear_bits(struct btrfs_block_group_cache *block_group,
+static void bitmap_clear_bits(struct btrfs_free_space_ctl *ctl,
struct btrfs_free_space *info, u64 offset,
u64 bytes)
{
unsigned long start, count;
- start = offset_to_bit(info->offset, block_group->sectorsize, offset);
- count = bytes_to_bits(bytes, block_group->sectorsize);
+ start = offset_to_bit(info->offset, ctl->unit, offset);
+ count = bytes_to_bits(bytes, ctl->unit);
BUG_ON(start + count > BITS_PER_BITMAP);
bitmap_clear(info->bitmap, start, count);
info->bytes -= bytes;
- block_group->free_space -= bytes;
+ ctl->free_space -= bytes;
}
-static void bitmap_set_bits(struct btrfs_block_group_cache *block_group,
+static void bitmap_set_bits(struct btrfs_free_space_ctl *ctl,
struct btrfs_free_space *info, u64 offset,
u64 bytes)
{
unsigned long start, count;
- start = offset_to_bit(info->offset, block_group->sectorsize, offset);
- count = bytes_to_bits(bytes, block_group->sectorsize);
+ start = offset_to_bit(info->offset, ctl->unit, offset);
+ count = bytes_to_bits(bytes, ctl->unit);
BUG_ON(start + count > BITS_PER_BITMAP);
bitmap_set(info->bitmap, start, count);
info->bytes += bytes;
- block_group->free_space += bytes;
+ ctl->free_space += bytes;
}
-static int search_bitmap(struct btrfs_block_group_cache *block_group,
+static int search_bitmap(struct btrfs_free_space_ctl *ctl,
struct btrfs_free_space *bitmap_info, u64 *offset,
u64 *bytes)
{
@@ -1170,9 +1174,9 @@
unsigned long bits, i;
unsigned long next_zero;
- i = offset_to_bit(bitmap_info->offset, block_group->sectorsize,
+ i = offset_to_bit(bitmap_info->offset, ctl->unit,
max_t(u64, *offset, bitmap_info->offset));
- bits = bytes_to_bits(*bytes, block_group->sectorsize);
+ bits = bytes_to_bits(*bytes, ctl->unit);
for (i = find_next_bit(bitmap_info->bitmap, BITS_PER_BITMAP, i);
i < BITS_PER_BITMAP;
@@ -1187,29 +1191,25 @@
}
if (found_bits) {
- *offset = (u64)(i * block_group->sectorsize) +
- bitmap_info->offset;
- *bytes = (u64)(found_bits) * block_group->sectorsize;
+ *offset = (u64)(i * ctl->unit) + bitmap_info->offset;
+ *bytes = (u64)(found_bits) * ctl->unit;
return 0;
}
return -1;
}
-static struct btrfs_free_space *find_free_space(struct btrfs_block_group_cache
- *block_group, u64 *offset,
- u64 *bytes, int debug)
+static struct btrfs_free_space *
+find_free_space(struct btrfs_free_space_ctl *ctl, u64 *offset, u64 *bytes)
{
struct btrfs_free_space *entry;
struct rb_node *node;
int ret;
- if (!block_group->free_space_offset.rb_node)
+ if (!ctl->free_space_offset.rb_node)
return NULL;
- entry = tree_search_offset(block_group,
- offset_to_bitmap(block_group, *offset),
- 0, 1);
+ entry = tree_search_offset(ctl, offset_to_bitmap(ctl, *offset), 0, 1);
if (!entry)
return NULL;
@@ -1219,7 +1219,7 @@
continue;
if (entry->bitmap) {
- ret = search_bitmap(block_group, entry, offset, bytes);
+ ret = search_bitmap(ctl, entry, offset, bytes);
if (!ret)
return entry;
continue;
@@ -1233,33 +1233,28 @@
return NULL;
}
-static void add_new_bitmap(struct btrfs_block_group_cache *block_group,
+static void add_new_bitmap(struct btrfs_free_space_ctl *ctl,
struct btrfs_free_space *info, u64 offset)
{
- u64 bytes_per_bg = BITS_PER_BITMAP * block_group->sectorsize;
- int max_bitmaps = (int)div64_u64(block_group->key.offset +
- bytes_per_bg - 1, bytes_per_bg);
- BUG_ON(block_group->total_bitmaps >= max_bitmaps);
-
- info->offset = offset_to_bitmap(block_group, offset);
+ info->offset = offset_to_bitmap(ctl, offset);
info->bytes = 0;
- link_free_space(block_group, info);
- block_group->total_bitmaps++;
+ link_free_space(ctl, info);
+ ctl->total_bitmaps++;
- recalculate_thresholds(block_group);
+ ctl->op->recalc_thresholds(ctl);
}
-static void free_bitmap(struct btrfs_block_group_cache *block_group,
+static void free_bitmap(struct btrfs_free_space_ctl *ctl,
struct btrfs_free_space *bitmap_info)
{
- unlink_free_space(block_group, bitmap_info);
+ unlink_free_space(ctl, bitmap_info);
kfree(bitmap_info->bitmap);
kmem_cache_free(btrfs_free_space_cachep, bitmap_info);
- block_group->total_bitmaps--;
- recalculate_thresholds(block_group);
+ ctl->total_bitmaps--;
+ ctl->op->recalc_thresholds(ctl);
}
-static noinline int remove_from_bitmap(struct btrfs_block_group_cache *block_group,
+static noinline int remove_from_bitmap(struct btrfs_free_space_ctl *ctl,
struct btrfs_free_space *bitmap_info,
u64 *offset, u64 *bytes)
{
@@ -1268,8 +1263,7 @@
int ret;
again:
- end = bitmap_info->offset +
- (u64)(BITS_PER_BITMAP * block_group->sectorsize) - 1;
+ end = bitmap_info->offset + (u64)(BITS_PER_BITMAP * ctl->unit) - 1;
/*
* XXX - this can go away after a few releases.
@@ -1284,24 +1278,22 @@
search_start = *offset;
search_bytes = *bytes;
search_bytes = min(search_bytes, end - search_start + 1);
- ret = search_bitmap(block_group, bitmap_info, &search_start,
- &search_bytes);
+ ret = search_bitmap(ctl, bitmap_info, &search_start, &search_bytes);
BUG_ON(ret < 0 || search_start != *offset);
if (*offset > bitmap_info->offset && *offset + *bytes > end) {
- bitmap_clear_bits(block_group, bitmap_info, *offset,
- end - *offset + 1);
+ bitmap_clear_bits(ctl, bitmap_info, *offset, end - *offset + 1);
*bytes -= end - *offset + 1;
*offset = end + 1;
} else if (*offset >= bitmap_info->offset && *offset + *bytes <= end) {
- bitmap_clear_bits(block_group, bitmap_info, *offset, *bytes);
+ bitmap_clear_bits(ctl, bitmap_info, *offset, *bytes);
*bytes = 0;
}
if (*bytes) {
struct rb_node *next = rb_next(&bitmap_info->offset_index);
if (!bitmap_info->bytes)
- free_bitmap(block_group, bitmap_info);
+ free_bitmap(ctl, bitmap_info);
/*
* no entry after this bitmap, but we still have bytes to
@@ -1328,31 +1320,28 @@
*/
search_start = *offset;
search_bytes = *bytes;
- ret = search_bitmap(block_group, bitmap_info, &search_start,
+ ret = search_bitmap(ctl, bitmap_info, &search_start,
&search_bytes);
if (ret < 0 || search_start != *offset)
return -EAGAIN;
goto again;
} else if (!bitmap_info->bytes)
- free_bitmap(block_group, bitmap_info);
+ free_bitmap(ctl, bitmap_info);
return 0;
}
-static int insert_into_bitmap(struct btrfs_block_group_cache *block_group,
- struct btrfs_free_space *info)
+static bool use_bitmap(struct btrfs_free_space_ctl *ctl,
+ struct btrfs_free_space *info)
{
- struct btrfs_free_space *bitmap_info;
- int added = 0;
- u64 bytes, offset, end;
- int ret;
+ struct btrfs_block_group_cache *block_group = ctl->private;
/*
* If we are below the extents threshold then we can add this as an
* extent, and don't have to deal with the bitmap
*/
- if (block_group->free_extents < block_group->extents_thresh) {
+ if (ctl->free_extents < ctl->extents_thresh) {
/*
* If this block group has some small extents we don't want to
* use up all of our free slots in the cache with them, we want
@@ -1361,11 +1350,10 @@
* the overhead of a bitmap if we don't have to.
*/
if (info->bytes <= block_group->sectorsize * 4) {
- if (block_group->free_extents * 2 <=
- block_group->extents_thresh)
- return 0;
+ if (ctl->free_extents * 2 <= ctl->extents_thresh)
+ return false;
} else {
- return 0;
+ return false;
}
}
@@ -1375,31 +1363,42 @@
*/
if (BITS_PER_BITMAP * block_group->sectorsize >
block_group->key.offset)
- return 0;
+ return false;
+
+ return true;
+}
+
+static int insert_into_bitmap(struct btrfs_free_space_ctl *ctl,
+ struct btrfs_free_space *info)
+{
+ struct btrfs_free_space *bitmap_info;
+ int added = 0;
+ u64 bytes, offset, end;
+ int ret;
bytes = info->bytes;
offset = info->offset;
+ if (!ctl->op->use_bitmap(ctl, info))
+ return 0;
+
again:
- bitmap_info = tree_search_offset(block_group,
- offset_to_bitmap(block_group, offset),
+ bitmap_info = tree_search_offset(ctl, offset_to_bitmap(ctl, offset),
1, 0);
if (!bitmap_info) {
BUG_ON(added);
goto new_bitmap;
}
- end = bitmap_info->offset +
- (u64)(BITS_PER_BITMAP * block_group->sectorsize);
+ end = bitmap_info->offset + (u64)(BITS_PER_BITMAP * ctl->unit);
if (offset >= bitmap_info->offset && offset + bytes > end) {
- bitmap_set_bits(block_group, bitmap_info, offset,
- end - offset);
+ bitmap_set_bits(ctl, bitmap_info, offset, end - offset);
bytes -= end - offset;
offset = end;
added = 0;
} else if (offset >= bitmap_info->offset && offset + bytes <= end) {
- bitmap_set_bits(block_group, bitmap_info, offset, bytes);
+ bitmap_set_bits(ctl, bitmap_info, offset, bytes);
bytes = 0;
} else {
BUG();
@@ -1413,19 +1412,19 @@
new_bitmap:
if (info && info->bitmap) {
- add_new_bitmap(block_group, info, offset);
+ add_new_bitmap(ctl, info, offset);
added = 1;
info = NULL;
goto again;
} else {
- spin_unlock(&block_group->tree_lock);
+ spin_unlock(&ctl->tree_lock);
/* no pre-allocated info, allocate a new one */
if (!info) {
info = kmem_cache_zalloc(btrfs_free_space_cachep,
GFP_NOFS);
if (!info) {
- spin_lock(&block_group->tree_lock);
+ spin_lock(&ctl->tree_lock);
ret = -ENOMEM;
goto out;
}
@@ -1433,7 +1432,7 @@
/* allocate the bitmap */
info->bitmap = kzalloc(PAGE_CACHE_SIZE, GFP_NOFS);
- spin_lock(&block_group->tree_lock);
+ spin_lock(&ctl->tree_lock);
if (!info->bitmap) {
ret = -ENOMEM;
goto out;
@@ -1451,7 +1450,7 @@
return ret;
}
-bool try_merge_free_space(struct btrfs_block_group_cache *block_group,
+bool try_merge_free_space(struct btrfs_free_space_ctl *ctl,
struct btrfs_free_space *info, bool update_stat)
{
struct btrfs_free_space *left_info;
@@ -1465,18 +1464,18 @@
* are adding, if there is remove that struct and add a new one to
* cover the entire range
*/
- right_info = tree_search_offset(block_group, offset + bytes, 0, 0);
+ right_info = tree_search_offset(ctl, offset + bytes, 0, 0);
if (right_info && rb_prev(&right_info->offset_index))
left_info = rb_entry(rb_prev(&right_info->offset_index),
struct btrfs_free_space, offset_index);
else
- left_info = tree_search_offset(block_group, offset - 1, 0, 0);
+ left_info = tree_search_offset(ctl, offset - 1, 0, 0);
if (right_info && !right_info->bitmap) {
if (update_stat)
- unlink_free_space(block_group, right_info);
+ unlink_free_space(ctl, right_info);
else
- __unlink_free_space(block_group, right_info);
+ __unlink_free_space(ctl, right_info);
info->bytes += right_info->bytes;
kmem_cache_free(btrfs_free_space_cachep, right_info);
merged = true;
@@ -1485,9 +1484,9 @@
if (left_info && !left_info->bitmap &&
left_info->offset + left_info->bytes == offset) {
if (update_stat)
- unlink_free_space(block_group, left_info);
+ unlink_free_space(ctl, left_info);
else
- __unlink_free_space(block_group, left_info);
+ __unlink_free_space(ctl, left_info);
info->offset = left_info->offset;
info->bytes += left_info->bytes;
kmem_cache_free(btrfs_free_space_cachep, left_info);
@@ -1500,6 +1499,7 @@
int btrfs_add_free_space(struct btrfs_block_group_cache *block_group,
u64 offset, u64 bytes)
{
+ struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
struct btrfs_free_space *info;
int ret = 0;
@@ -1510,9 +1510,9 @@
info->offset = offset;
info->bytes = bytes;
- spin_lock(&block_group->tree_lock);
+ spin_lock(&ctl->tree_lock);
- if (try_merge_free_space(block_group, info, true))
+ if (try_merge_free_space(ctl, info, true))
goto link;
/*
@@ -1520,7 +1520,7 @@
* extent then we know we're going to have to allocate a new extent, so
* before we do that see if we need to drop this into a bitmap
*/
- ret = insert_into_bitmap(block_group, info);
+ ret = insert_into_bitmap(ctl, info);
if (ret < 0) {
goto out;
} else if (ret) {
@@ -1528,11 +1528,11 @@
goto out;
}
link:
- ret = link_free_space(block_group, info);
+ ret = link_free_space(ctl, info);
if (ret)
kmem_cache_free(btrfs_free_space_cachep, info);
out:
- spin_unlock(&block_group->tree_lock);
+ spin_unlock(&ctl->tree_lock);
if (ret) {
printk(KERN_CRIT "btrfs: unable to add free space :%d\n", ret);
@@ -1545,21 +1545,21 @@
int btrfs_remove_free_space(struct btrfs_block_group_cache *block_group,
u64 offset, u64 bytes)
{
+ struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
struct btrfs_free_space *info;
struct btrfs_free_space *next_info = NULL;
int ret = 0;
- spin_lock(&block_group->tree_lock);
+ spin_lock(&ctl->tree_lock);
again:
- info = tree_search_offset(block_group, offset, 0, 0);
+ info = tree_search_offset(ctl, offset, 0, 0);
if (!info) {
/*
* oops didn't find an extent that matched the space we wanted
* to remove, look for a bitmap instead
*/
- info = tree_search_offset(block_group,
- offset_to_bitmap(block_group, offset),
+ info = tree_search_offset(ctl, offset_to_bitmap(ctl, offset),
1, 0);
if (!info) {
WARN_ON(1);
@@ -1574,8 +1574,8 @@
offset_index);
if (next_info->bitmap)
- end = next_info->offset + BITS_PER_BITMAP *
- block_group->sectorsize - 1;
+ end = next_info->offset +
+ BITS_PER_BITMAP * ctl->unit - 1;
else
end = next_info->offset + next_info->bytes;
@@ -1595,20 +1595,20 @@
}
if (info->bytes == bytes) {
- unlink_free_space(block_group, info);
+ unlink_free_space(ctl, info);
if (info->bitmap) {
kfree(info->bitmap);
- block_group->total_bitmaps--;
+ ctl->total_bitmaps--;
}
kmem_cache_free(btrfs_free_space_cachep, info);
goto out_lock;
}
if (!info->bitmap && info->offset == offset) {
- unlink_free_space(block_group, info);
+ unlink_free_space(ctl, info);
info->offset += bytes;
info->bytes -= bytes;
- link_free_space(block_group, info);
+ link_free_space(ctl, info);
goto out_lock;
}
@@ -1622,13 +1622,13 @@
* first unlink the old info and then
* insert it again after the hole we're creating
*/
- unlink_free_space(block_group, info);
+ unlink_free_space(ctl, info);
if (offset + bytes < info->offset + info->bytes) {
u64 old_end = info->offset + info->bytes;
info->offset = offset + bytes;
info->bytes = old_end - info->offset;
- ret = link_free_space(block_group, info);
+ ret = link_free_space(ctl, info);
WARN_ON(ret);
if (ret)
goto out_lock;
@@ -1638,7 +1638,7 @@
*/
kmem_cache_free(btrfs_free_space_cachep, info);
}
- spin_unlock(&block_group->tree_lock);
+ spin_unlock(&ctl->tree_lock);
/* step two, insert a new info struct to cover
* anything before the hole
@@ -1649,12 +1649,12 @@
goto out;
}
- ret = remove_from_bitmap(block_group, info, &offset, &bytes);
+ ret = remove_from_bitmap(ctl, info, &offset, &bytes);
if (ret == -EAGAIN)
goto again;
BUG_ON(ret);
out_lock:
- spin_unlock(&block_group->tree_lock);
+ spin_unlock(&ctl->tree_lock);
out:
return ret;
}
@@ -1662,11 +1662,12 @@
void btrfs_dump_free_space(struct btrfs_block_group_cache *block_group,
u64 bytes)
{
+ struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
struct btrfs_free_space *info;
struct rb_node *n;
int count = 0;
- for (n = rb_first(&block_group->free_space_offset); n; n = rb_next(n)) {
+ for (n = rb_first(&ctl->free_space_offset); n; n = rb_next(n)) {
info = rb_entry(n, struct btrfs_free_space, offset_index);
if (info->bytes >= bytes)
count++;
@@ -1681,6 +1682,30 @@
"\n", count);
}
+static struct btrfs_free_space_op free_space_op = {
+ .recalc_thresholds = recalculate_thresholds,
+ .use_bitmap = use_bitmap,
+};
+
+void btrfs_init_free_space_ctl(struct btrfs_block_group_cache *block_group)
+{
+ struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
+
+ spin_lock_init(&ctl->tree_lock);
+ ctl->unit = block_group->sectorsize;
+ ctl->start = block_group->key.objectid;
+ ctl->private = block_group;
+ ctl->op = &free_space_op;
+
+ /*
+ * we only want to have 32k of ram per block group for keeping
+ * track of free space, and if we pass 1/2 of that we want to
+ * start converting things over to using bitmaps
+ */
+ ctl->extents_thresh = ((1024 * 32) / 2) /
+ sizeof(struct btrfs_free_space);
+}
+
/*
* for a given cluster, put all of its extents back into the free
* space cache. If the block group passed doesn't match the block group
@@ -1692,6 +1717,7 @@
struct btrfs_block_group_cache *block_group,
struct btrfs_free_cluster *cluster)
{
+ struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
struct btrfs_free_space *entry;
struct rb_node *node;
@@ -1713,8 +1739,8 @@
bitmap = (entry->bitmap != NULL);
if (!bitmap)
- try_merge_free_space(block_group, entry, false);
- tree_insert_offset(&block_group->free_space_offset,
+ try_merge_free_space(ctl, entry, false);
+ tree_insert_offset(&ctl->free_space_offset,
entry->offset, &entry->offset_index, bitmap);
}
cluster->root = RB_ROOT;
@@ -1727,12 +1753,13 @@
void btrfs_remove_free_space_cache(struct btrfs_block_group_cache *block_group)
{
+ struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
struct btrfs_free_space *info;
struct rb_node *node;
struct btrfs_free_cluster *cluster;
struct list_head *head;
- spin_lock(&block_group->tree_lock);
+ spin_lock(&ctl->tree_lock);
while ((head = block_group->cluster_list.next) !=
&block_group->cluster_list) {
cluster = list_entry(head, struct btrfs_free_cluster,
@@ -1741,57 +1768,58 @@
WARN_ON(cluster->block_group != block_group);
__btrfs_return_cluster_to_free_space(block_group, cluster);
if (need_resched()) {
- spin_unlock(&block_group->tree_lock);
+ spin_unlock(&ctl->tree_lock);
cond_resched();
- spin_lock(&block_group->tree_lock);
+ spin_lock(&ctl->tree_lock);
}
}
- while ((node = rb_last(&block_group->free_space_offset)) != NULL) {
+ while ((node = rb_last(&ctl->free_space_offset)) != NULL) {
info = rb_entry(node, struct btrfs_free_space, offset_index);
- unlink_free_space(block_group, info);
+ unlink_free_space(ctl, info);
if (info->bitmap)
kfree(info->bitmap);
kmem_cache_free(btrfs_free_space_cachep, info);
if (need_resched()) {
- spin_unlock(&block_group->tree_lock);
+ spin_unlock(&ctl->tree_lock);
cond_resched();
- spin_lock(&block_group->tree_lock);
+ spin_lock(&ctl->tree_lock);
}
}
- spin_unlock(&block_group->tree_lock);
+ spin_unlock(&ctl->tree_lock);
}
u64 btrfs_find_space_for_alloc(struct btrfs_block_group_cache *block_group,
u64 offset, u64 bytes, u64 empty_size)
{
+ struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
struct btrfs_free_space *entry = NULL;
u64 bytes_search = bytes + empty_size;
u64 ret = 0;
- spin_lock(&block_group->tree_lock);
- entry = find_free_space(block_group, &offset, &bytes_search, 0);
+ spin_lock(&ctl->tree_lock);
+ entry = find_free_space(ctl, &offset, &bytes_search);
if (!entry)
goto out;
ret = offset;
if (entry->bitmap) {
- bitmap_clear_bits(block_group, entry, offset, bytes);
+ bitmap_clear_bits(ctl, entry, offset, bytes);
if (!entry->bytes)
- free_bitmap(block_group, entry);
+ free_bitmap(ctl, entry);
} else {
- unlink_free_space(block_group, entry);
+ unlink_free_space(ctl, entry);
entry->offset += bytes;
entry->bytes -= bytes;
if (!entry->bytes)
kmem_cache_free(btrfs_free_space_cachep, entry);
else
- link_free_space(block_group, entry);
+ link_free_space(ctl, entry);
}
out:
- spin_unlock(&block_group->tree_lock);
+ spin_unlock(&ctl->tree_lock);
return ret;
}
@@ -1808,6 +1836,7 @@
struct btrfs_block_group_cache *block_group,
struct btrfs_free_cluster *cluster)
{
+ struct btrfs_free_space_ctl *ctl;
int ret;
/* first, get a safe pointer to the block group */
@@ -1826,10 +1855,12 @@
atomic_inc(&block_group->count);
spin_unlock(&cluster->lock);
+ ctl = block_group->free_space_ctl;
+
/* now return any extents the cluster had on it */
- spin_lock(&block_group->tree_lock);
+ spin_lock(&ctl->tree_lock);
ret = __btrfs_return_cluster_to_free_space(block_group, cluster);
- spin_unlock(&block_group->tree_lock);
+ spin_unlock(&ctl->tree_lock);
/* finally drop our ref */
btrfs_put_block_group(block_group);
@@ -1841,6 +1872,7 @@
struct btrfs_free_space *entry,
u64 bytes, u64 min_start)
{
+ struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
int err;
u64 search_start = cluster->window_start;
u64 search_bytes = bytes;
@@ -1849,13 +1881,12 @@
search_start = min_start;
search_bytes = bytes;
- err = search_bitmap(block_group, entry, &search_start,
- &search_bytes);
+ err = search_bitmap(ctl, entry, &search_start, &search_bytes);
if (err)
return 0;
ret = search_start;
- bitmap_clear_bits(block_group, entry, ret, bytes);
+ bitmap_clear_bits(ctl, entry, ret, bytes);
return ret;
}
@@ -1869,6 +1900,7 @@
struct btrfs_free_cluster *cluster, u64 bytes,
u64 min_start)
{
+ struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
struct btrfs_free_space *entry = NULL;
struct rb_node *node;
u64 ret = 0;
@@ -1929,20 +1961,20 @@
if (!ret)
return 0;
- spin_lock(&block_group->tree_lock);
+ spin_lock(&ctl->tree_lock);
- block_group->free_space -= bytes;
+ ctl->free_space -= bytes;
if (entry->bytes == 0) {
- block_group->free_extents--;
+ ctl->free_extents--;
if (entry->bitmap) {
kfree(entry->bitmap);
- block_group->total_bitmaps--;
- recalculate_thresholds(block_group);
+ ctl->total_bitmaps--;
+ ctl->op->recalc_thresholds(ctl);
}
kmem_cache_free(btrfs_free_space_cachep, entry);
}
- spin_unlock(&block_group->tree_lock);
+ spin_unlock(&ctl->tree_lock);
return ret;
}
@@ -1952,6 +1984,7 @@
struct btrfs_free_cluster *cluster,
u64 offset, u64 bytes, u64 min_bytes)
{
+ struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
unsigned long next_zero;
unsigned long i;
unsigned long search_bits;
@@ -2006,7 +2039,7 @@
cluster->window_start = start * block_group->sectorsize +
entry->offset;
- rb_erase(&entry->offset_index, &block_group->free_space_offset);
+ rb_erase(&entry->offset_index, &ctl->free_space_offset);
ret = tree_insert_offset(&cluster->root, entry->offset,
&entry->offset_index, 1);
BUG_ON(ret);
@@ -2021,6 +2054,7 @@
struct btrfs_free_cluster *cluster,
u64 offset, u64 bytes, u64 min_bytes)
{
+ struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
struct btrfs_free_space *first = NULL;
struct btrfs_free_space *entry = NULL;
struct btrfs_free_space *prev = NULL;
@@ -2031,7 +2065,7 @@
u64 max_extent;
u64 max_gap = 128 * 1024;
- entry = tree_search_offset(block_group, offset, 0, 1);
+ entry = tree_search_offset(ctl, offset, 0, 1);
if (!entry)
return -ENOSPC;
@@ -2097,7 +2131,7 @@
if (entry->bitmap)
continue;
- rb_erase(&entry->offset_index, &block_group->free_space_offset);
+ rb_erase(&entry->offset_index, &ctl->free_space_offset);
ret = tree_insert_offset(&cluster->root, entry->offset,
&entry->offset_index, 0);
BUG_ON(ret);
@@ -2116,16 +2150,15 @@
struct btrfs_free_cluster *cluster,
u64 offset, u64 bytes, u64 min_bytes)
{
+ struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
struct btrfs_free_space *entry;
struct rb_node *node;
int ret = -ENOSPC;
- if (block_group->total_bitmaps == 0)
+ if (ctl->total_bitmaps == 0)
return -ENOSPC;
- entry = tree_search_offset(block_group,
- offset_to_bitmap(block_group, offset),
- 0, 1);
+ entry = tree_search_offset(ctl, offset_to_bitmap(ctl, offset), 0, 1);
if (!entry)
return -ENOSPC;
@@ -2158,6 +2191,7 @@
struct btrfs_free_cluster *cluster,
u64 offset, u64 bytes, u64 empty_size)
{
+ struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
u64 min_bytes;
int ret;
@@ -2177,14 +2211,14 @@
} else
min_bytes = max(bytes, (bytes + empty_size) >> 2);
- spin_lock(&block_group->tree_lock);
+ spin_lock(&ctl->tree_lock);
/*
* If we know we don't have enough space to make a cluster don't even
* bother doing all the work to try and find one.
*/
- if (block_group->free_space < min_bytes) {
- spin_unlock(&block_group->tree_lock);
+ if (ctl->free_space < min_bytes) {
+ spin_unlock(&ctl->tree_lock);
return -ENOSPC;
}
@@ -2210,7 +2244,7 @@
}
out:
spin_unlock(&cluster->lock);
- spin_unlock(&block_group->tree_lock);
+ spin_unlock(&ctl->tree_lock);
return ret;
}
@@ -2231,6 +2265,7 @@
int btrfs_trim_block_group(struct btrfs_block_group_cache *block_group,
u64 *trimmed, u64 start, u64 end, u64 minlen)
{
+ struct btrfs_free_space_ctl *ctl = block_group->free_space_ctl;
struct btrfs_free_space *entry = NULL;
struct btrfs_fs_info *fs_info = block_group->fs_info;
u64 bytes = 0;
@@ -2240,52 +2275,50 @@
*trimmed = 0;
while (start < end) {
- spin_lock(&block_group->tree_lock);
+ spin_lock(&ctl->tree_lock);
- if (block_group->free_space < minlen) {
- spin_unlock(&block_group->tree_lock);
+ if (ctl->free_space < minlen) {
+ spin_unlock(&ctl->tree_lock);
break;
}
- entry = tree_search_offset(block_group, start, 0, 1);
+ entry = tree_search_offset(ctl, start, 0, 1);
if (!entry)
- entry = tree_search_offset(block_group,
- offset_to_bitmap(block_group,
- start),
+ entry = tree_search_offset(ctl,
+ offset_to_bitmap(ctl, start),
1, 1);
if (!entry || entry->offset >= end) {
- spin_unlock(&block_group->tree_lock);
+ spin_unlock(&ctl->tree_lock);
break;
}
if (entry->bitmap) {
- ret = search_bitmap(block_group, entry, &start, &bytes);
+ ret = search_bitmap(ctl, entry, &start, &bytes);
if (!ret) {
if (start >= end) {
- spin_unlock(&block_group->tree_lock);
+ spin_unlock(&ctl->tree_lock);
break;
}
bytes = min(bytes, end - start);
- bitmap_clear_bits(block_group, entry,
- start, bytes);
+ bitmap_clear_bits(ctl, entry, start, bytes);
if (entry->bytes == 0)
- free_bitmap(block_group, entry);
+ free_bitmap(ctl, entry);
} else {
start = entry->offset + BITS_PER_BITMAP *
block_group->sectorsize;
- spin_unlock(&block_group->tree_lock);
+ spin_unlock(&ctl->tree_lock);
ret = 0;
continue;
}
} else {
start = entry->offset;
bytes = min(entry->bytes, end - start);
- unlink_free_space(block_group, entry);
+ unlink_free_space(ctl, entry);
kfree(entry);
}
- spin_unlock(&block_group->tree_lock);
+ spin_unlock(&ctl->tree_lock);
if (bytes >= minlen) {
int update_ret;
@@ -2297,8 +2330,7 @@
bytes,
&actually_trimmed);
- btrfs_add_free_space(block_group,
- start, bytes);
+ btrfs_add_free_space(block_group, start, bytes);
if (!update_ret)
btrfs_update_reserved_bytes(block_group,
bytes, 0, 1);