@@ -877,7 +877,7 @@ out:
btrfs_free_path(path);
error:
*start = max_hole_start;
- if (len && max_hole_size > *len)
+ if (len)
*len = max_hole_size;
return ret;
}
@@ -2176,70 +2176,67 @@ static noinline u64 chunk_bytes_by_type(u64 type, u64 calc_size,
return calc_size * num_stripes;
}
-static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
- struct btrfs_root *extent_root,
- struct map_lookup **map_ret,
- u64 *num_bytes, u64 *stripe_size,
- u64 start, u64 type)
+/* Used to sort the devices by max_avail(descending sort) */
+int btrfs_cmp_device_free_bytes(const void *dev_info1, const void *dev_info2)
{
- struct btrfs_fs_info *info = extent_root->fs_info;
- struct btrfs_device *device = NULL;
- struct btrfs_fs_devices *fs_devices = info->fs_devices;
- struct list_head *cur;
- struct map_lookup *map = NULL;
- struct extent_map_tree *em_tree;
- struct extent_map *em;
- struct list_head private_devs;
- int min_stripe_size = 1 * 1024 * 1024;
- u64 calc_size = 1024 * 1024 * 1024;
- u64 max_chunk_size = calc_size;
- u64 min_free;
- u64 avail;
- u64 max_avail = 0;
- u64 dev_offset;
- int num_stripes = 1;
- int min_stripes = 1;
- int sub_stripes = 0;
- int ncopies = 1;
- int looped = 0;
- int ret;
- int index;
- int stripe_len = 64 * 1024;
+ if (((struct btrfs_device_info *)dev_info1)->max_avail >
+ ((struct btrfs_device_info *)dev_info2)->max_avail)
+ return -1;
+ else if (((struct btrfs_device_info *)dev_info1)->max_avail <
+ ((struct btrfs_device_info *)dev_info2)->max_avail)
+ return 1;
+ else
+ return 0;
+}
- if ((type & BTRFS_BLOCK_GROUP_RAID1) &&
- (type & BTRFS_BLOCK_GROUP_DUP)) {
- WARN_ON(1);
- type &= ~BTRFS_BLOCK_GROUP_DUP;
- }
- if (list_empty(&fs_devices->alloc_list))
- return -ENOSPC;
+static int __btrfs_calc_nstripes(struct btrfs_fs_devices *fs_devices, u64 type,
+ int *num_stripes, int *min_stripes,
+ int *sub_stripes)
+{
+ *num_stripes = 1;
+ *min_stripes = 1;
+ *sub_stripes = 0;
if (type & (BTRFS_BLOCK_GROUP_RAID0)) {
- num_stripes = fs_devices->rw_devices;
- min_stripes = 2;
+ *num_stripes = fs_devices->rw_devices;
+ *min_stripes = 2;
}
if (type & (BTRFS_BLOCK_GROUP_DUP)) {
- num_stripes = 2;
- min_stripes = 2;
- ncopies = 2;
+ *num_stripes = 2;
+ *min_stripes = 2;
}
if (type & (BTRFS_BLOCK_GROUP_RAID1)) {
if (fs_devices->rw_devices < 2)
return -ENOSPC;
- num_stripes = 2;
- min_stripes = 2;
- ncopies = 2;
+ *num_stripes = 2;
+ *min_stripes = 2;
}
if (type & (BTRFS_BLOCK_GROUP_RAID10)) {
- num_stripes = fs_devices->rw_devices;
- if (num_stripes < 4)
+ *num_stripes = fs_devices->rw_devices;
+ if (*num_stripes < 4)
return -ENOSPC;
- num_stripes &= ~(u32)1;
- sub_stripes = 2;
- ncopies = 2;
- min_stripes = 4;
+ *num_stripes &= ~(u32)1;
+ *sub_stripes = 2;
+ *min_stripes = 4;
}
+ return 0;
+}
+
+static u64 __btrfs_calc_stripe_size(struct btrfs_fs_devices *fs_devices,
+ u64 proposed_size, u64 type,
+ int num_stripes, int small_stripe)
+{
+ int min_stripe_size = 1 * 1024 * 1024;
+ u64 calc_size = proposed_size;
+ u64 max_chunk_size = calc_size;
+ int ncopies = 1;
+
+ if (type & (BTRFS_BLOCK_GROUP_RAID1 |
+ BTRFS_BLOCK_GROUP_DUP |
+ BTRFS_BLOCK_GROUP_RAID10))
+ ncopies = 2;
+
if (type & BTRFS_BLOCK_GROUP_DATA) {
max_chunk_size = 10 * calc_size;
min_stripe_size = 64 * 1024 * 1024;
@@ -2256,51 +2253,208 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
max_chunk_size = min(div_factor(fs_devices->total_rw_bytes, 1),
max_chunk_size);
-again:
- max_avail = 0;
- if (!map || map->num_stripes != num_stripes) {
- kfree(map);
- map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
- if (!map)
- return -ENOMEM;
- map->num_stripes = num_stripes;
- }
-
if (calc_size * num_stripes > max_chunk_size * ncopies) {
calc_size = max_chunk_size * ncopies;
do_div(calc_size, num_stripes);
- do_div(calc_size, stripe_len);
- calc_size *= stripe_len;
+ do_div(calc_size, BTRFS_STRIPE_LEN);
+ calc_size *= BTRFS_STRIPE_LEN;
}
/* we don't want tiny stripes */
- if (!looped)
+ if (!small_stripe)
calc_size = max_t(u64, min_stripe_size, calc_size);
/*
- * we're about to do_div by the stripe_len so lets make sure
+ * we're about to do_div by the BTRFS_STRIPE_LEN so lets make sure
* we end up with something bigger than a stripe
*/
- calc_size = max_t(u64, calc_size, stripe_len * 4);
+ calc_size = max_t(u64, calc_size, BTRFS_STRIPE_LEN);
+
+ do_div(calc_size, BTRFS_STRIPE_LEN);
+ calc_size *= BTRFS_STRIPE_LEN;
+
+ return calc_size;
+}
+
+static struct map_lookup *__shrink_map_lookup_stripes(struct map_lookup *map,
+ int num_stripes)
+{
+ struct map_lookup *new;
+ size_t len = map_lookup_size(num_stripes);
+
+ BUG_ON(map->num_stripes < num_stripes);
+
+ if (map->num_stripes == num_stripes)
+ return map;
+
+ new = kmalloc(len, GFP_NOFS);
+ if (!new) {
+ /* just change map->num_stripes */
+ map->num_stripes = num_stripes;
+ return map;
+ }
+
+ memcpy(new, map, len);
+ new->num_stripes = num_stripes;
+ kfree(map);
+ return new;
+}
+
+/*
+ * helper to allocate device space from btrfs_device_info, in which we stored
+ * max free space information of every device. It is used when we can not
+ * allocate chunks by default size.
+ *
+ * By this helper, we can allocate a new chunk as larger as possible.
+ */
+static struct map_lookup *__btrfs_alloc_tiny_space(
+ struct btrfs_trans_handle *trans,
+ struct btrfs_fs_devices *fs_devices,
+ struct btrfs_device_info *devices,
+ int nr_device, u64 type,
+ struct map_lookup *map,
+ int min_stripes, u64 *stripe_size)
+{
+ int i, index, sort_again = 0;
+ int min_devices = min_stripes;
+ u64 max_avail, min_free;
+ int ret;
- do_div(calc_size, stripe_len);
- calc_size *= stripe_len;
+ if (nr_device < min_stripes)
+ return ERR_PTR(-ENOSPC);
+
+ btrfs_descending_sort_devices(devices, nr_device);
+
+ max_avail = devices[0].max_avail;
+ if (!max_avail)
+ return ERR_PTR(-ENOSPC);
+
+ for (i = 0; i < nr_device; i++) {
+ /*
+ * if dev_offset = 0, it means the free space of this device
+ * is less than what we need, and we didn't search max avail
+ * extent on this device, so do it now.
+ */
+ if (!devices[i].dev_offset) {
+ ret = find_free_dev_extent(trans, devices[i].dev,
+ max_avail,
+ &devices[i].dev_offset,
+ &devices[i].max_avail);
+ if (ret != 0 && ret != -ENOSPC)
+ return ERR_PTR(ret);
+ sort_again = 1;
+ }
+ }
+
+ /* we update the max avail free extent of each devices, sort again */
+ if (sort_again)
+ btrfs_descending_sort_devices(devices, nr_device);
+
+ if (type & BTRFS_BLOCK_GROUP_DUP)
+ min_devices = 1;
+
+ if (!devices[min_devices - 1].max_avail)
+ return ERR_PTR(-ENOSPC);
+
+ max_avail = devices[min_devices - 1].max_avail;
+ if (type & BTRFS_BLOCK_GROUP_DUP)
+ do_div(max_avail, 2);
+
+ max_avail = __btrfs_calc_stripe_size(fs_devices, max_avail, type,
+ min_stripes, 1);
+ if (type & BTRFS_BLOCK_GROUP_DUP)
+ min_free = max_avail * 2;
+ else
+ min_free = max_avail;
+
+ if (min_free > devices[min_devices - 1].max_avail)
+ return ERR_PTR(-ENOSPC);
+
+ map = __shrink_map_lookup_stripes(map, min_stripes);
+ *stripe_size = max_avail;
+
+ index = 0;
+ for (i = 0; i < min_stripes; i++) {
+ map->stripes[i].dev = devices[index].dev;
+ map->stripes[i].physical = devices[index].dev_offset;
+ if (type & BTRFS_BLOCK_GROUP_DUP) {
+ i++;
+ map->stripes[i].dev = devices[index].dev;
+ map->stripes[i].physical = devices[index].dev_offset +
+ max_avail;
+ }
+ index++;
+ }
+
+ return map;
+}
+
+static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
+ struct btrfs_root *extent_root,
+ struct map_lookup **map_ret,
+ u64 *num_bytes, u64 *stripe_size,
+ u64 start, u64 type)
+{
+ struct btrfs_fs_info *info = extent_root->fs_info;
+ struct btrfs_device *device = NULL;
+ struct btrfs_fs_devices *fs_devices = info->fs_devices;
+ struct list_head *cur;
+ struct map_lookup *map;
+ struct extent_map_tree *em_tree;
+ struct extent_map *em;
+ struct btrfs_device_info *devices_info;
+ struct list_head private_devs;
+ u64 calc_size = 1024 * 1024 * 1024;
+ u64 min_free;
+ u64 avail;
+ u64 dev_offset;
+ int num_stripes;
+ int min_stripes;
+ int sub_stripes;
+ int min_devices; /* the min number of devices we need */
+ int i;
+ int ret;
+ int index;
+
+ if ((type & BTRFS_BLOCK_GROUP_RAID1) &&
+ (type & BTRFS_BLOCK_GROUP_DUP)) {
+ WARN_ON(1);
+ type &= ~BTRFS_BLOCK_GROUP_DUP;
+ }
+ if (list_empty(&fs_devices->alloc_list))
+ return -ENOSPC;
+
+ ret = __btrfs_calc_nstripes(fs_devices, type, &num_stripes,
+ &min_stripes, &sub_stripes);
+ if (ret)
+ return ret;
+
+ devices_info = kzalloc(sizeof(*devices_info) * fs_devices->rw_devices,
+ GFP_NOFS);
+ if (!devices_info)
+ return -ENOMEM;
+
+ map = kmalloc(map_lookup_size(num_stripes), GFP_NOFS);
+ if (!map) {
+ ret = -ENOMEM;
+ goto error;
+ }
+ map->num_stripes = num_stripes;
cur = fs_devices->alloc_list.next;
index = 0;
+ i = 0;
- if (type & BTRFS_BLOCK_GROUP_DUP)
+ calc_size = __btrfs_calc_stripe_size(fs_devices, calc_size, type,
+ num_stripes, 0);
+
+ if (type & BTRFS_BLOCK_GROUP_DUP) {
min_free = calc_size * 2;
- else
+ min_devices = 1;
+ } else {
min_free = calc_size;
-
- /*
- * we add 1MB because we never use the first 1MB of the device, unless
- * we've looped, then we are likely allocating the maximum amount of
- * space left already
- */
- if (!looped)
- min_free += 1024 * 1024;
+ min_devices = min_stripes;
+ }
INIT_LIST_HEAD(&private_devs);
while (index < num_stripes) {
@@ -2313,27 +2467,39 @@ again:
cur = cur->next;
if (device->in_fs_metadata && avail >= min_free) {
- ret = find_free_dev_extent(trans, device,
- min_free, &dev_offset,
- &max_avail);
+ ret = find_free_dev_extent(trans, device, min_free,
+ &devices_info[i].dev_offset,
+ &devices_info[i].max_avail);
if (ret == 0) {
list_move_tail(&device->dev_alloc_list,
&private_devs);
map->stripes[index].dev = device;
- map->stripes[index].physical = dev_offset;
+ map->stripes[index].physical =
+ devices_info[i].dev_offset;
index++;
if (type & BTRFS_BLOCK_GROUP_DUP) {
map->stripes[index].dev = device;
map->stripes[index].physical =
- dev_offset + calc_size;
+ devices_info[i].dev_offset +
+ calc_size;
index++;
}
- }
- } else if (device->in_fs_metadata && avail > max_avail)
- max_avail = avail;
+ } else if (ret != -ENOSPC)
+ goto error;
+
+ devices_info[i].dev = device;
+ i++;
+ } else if (device->in_fs_metadata &&
+ avail >= BTRFS_STRIPE_LEN) {
+ devices_info[i].dev = device;
+ devices_info[i].max_avail = avail;
+ i++;
+ }
+
if (cur == &fs_devices->alloc_list)
break;
}
+
list_splice(&private_devs, &fs_devices->alloc_list);
if (index < num_stripes) {
if (index >= min_stripes) {
@@ -2342,36 +2508,38 @@ again:
num_stripes /= sub_stripes;
num_stripes *= sub_stripes;
}
- looped = 1;
- goto again;
- }
- if (!looped && max_avail > 0) {
- looped = 1;
- calc_size = max_avail;
- if (type & BTRFS_BLOCK_GROUP_DUP)
- do_div(calc_size, 2);
- goto again;
+
+ map = __shrink_map_lookup_stripes(map, num_stripes);
+ } else if (i >= min_devices) {
+ map = __btrfs_alloc_tiny_space(trans, fs_devices,
+ devices_info, i, type,
+ map, min_stripes,
+ &calc_size);
+ if (IS_ERR(map)) {
+ ret = PTR_ERR(map);
+ goto error;
+ }
+ } else {
+ ret = -ENOSPC;
+ goto error;
}
- kfree(map);
- return -ENOSPC;
}
map->sector_size = extent_root->sectorsize;
- map->stripe_len = stripe_len;
- map->io_align = stripe_len;
- map->io_width = stripe_len;
+ map->stripe_len = BTRFS_STRIPE_LEN;
+ map->io_align = BTRFS_STRIPE_LEN;
+ map->io_width = BTRFS_STRIPE_LEN;
map->type = type;
- map->num_stripes = num_stripes;
map->sub_stripes = sub_stripes;
*map_ret = map;
*stripe_size = calc_size;
*num_bytes = chunk_bytes_by_type(type, calc_size,
- num_stripes, sub_stripes);
+ map->num_stripes, sub_stripes);
em = alloc_extent_map(GFP_NOFS);
if (!em) {
- kfree(map);
- return -ENOMEM;
+ ret = -ENOMEM;
+ goto error;
}
em->bdev = (struct block_device *)map;
em->start = start;
@@ -2404,7 +2572,13 @@ again:
index++;
}
+ kfree(devices_info);
return 0;
+
+error:
+ kfree(map);
+ kfree(devices_info);
+ return ret;
}
static int __finish_chunk_alloc(struct btrfs_trans_handle *trans,
@@ -20,8 +20,11 @@
#define __BTRFS_VOLUMES_
#include <linux/bio.h>
+#include <linux/sort.h>
#include "async-thread.h"
+#define BTRFS_STRIPE_LEN (64 * 1024)
+
struct buffer_head;
struct btrfs_pending_bios {
struct bio *head;
@@ -137,6 +140,27 @@ struct btrfs_multi_bio {
struct btrfs_bio_stripe stripes[];
};
+struct btrfs_device_info {
+ struct btrfs_device *dev;
+ u64 dev_offset;
+ u64 max_avail;
+};
+
+/* Used to sort the devices by max_avail(descending sort) */
+int btrfs_cmp_device_free_bytes(const void *dev_info1, const void *dev_info2);
+
+/*
+ * sort the devices by max_avail, in which max free extent size of each device
+ * is stored.(Descending Sort)
+ */
+static inline void btrfs_descending_sort_devices(
+ struct btrfs_device_info *devices,
+ size_t nr_devices)
+{
+ sort(devices, nr_devices, sizeof(struct btrfs_device_info),
+ btrfs_cmp_device_free_bytes, NULL);
+}
+
#define btrfs_multi_bio_size(n) (sizeof(struct btrfs_multi_bio) + \
(sizeof(struct btrfs_bio_stripe) * (n)))