[PATCH v4 07/13] btrfs: zoned: use generic btrfs zone helpers to support npo2 zoned devices

Pankaj Raghav
2022-05-16T16:54:43Z

Add helpers to calculate alignment, round up and round down
for zoned devices. These helpers encapsulates the necessary handling for
power_of_2 and non-power_of_2 zone sizes. Optimized calculations are
performed for zone sizes that are power_of_2 with log and shifts.

btrfs_zoned_is_aligned() is added instead of reusing bdev_zone_aligned()
helper due to some use cases in btrfs where zone alignment is checked
before having access to the underlying block device such as in this
function: btrfs_load_block_group_zone_info().

Use the generic btrfs zone helpers to calculate zone index, check zone
alignment, round up and round down operations.

The zone_size_shift field is not needed anymore as generic helpers are
used for calculation.

Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Pankaj Raghav <p.raghav@samsung.com>
---
fs/btrfs/volumes.c | 24 +++++++++-------
fs/btrfs/zoned.c | 72 ++++++++++++++++++++++------------------------
fs/btrfs/zoned.h | 43 +++++++++++++++++++++++----
3 files changed, 85 insertions(+), 54 deletions(-)

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index 94f851592..3d6b9a25a 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1408,7 +1408,7 @@ static u64 dev_extent_search_start(struct btrfs_device *device, u64 start)
* allocator, because we anyway use/reserve the first two zones
* for superblock logging.
*/
- return ALIGN(start, device->zone_info->zone_size);
+ return btrfs_zoned_roundup(start, device->zone_info->zone_size);
default:
BUG();
}
@@ -1423,7 +1423,7 @@ static bool dev_extent_hole_check_zoned(struct btrfs_device *device,
int ret;
bool changed = false;

- ASSERT(IS_ALIGNED(*hole_start, zone_size));
+ ASSERT(btrfs_zoned_is_aligned(*hole_start, zone_size));

while (*hole_size > 0) {
pos = btrfs_find_allocatable_zones(device, *hole_start,
@@ -1560,7 +1560,7 @@ static int find_free_dev_extent_start(struct btrfs_device *device,
search_start = dev_extent_search_start(device, search_start);

WARN_ON(device->zone_info &&
- !IS_ALIGNED(num_bytes, device->zone_info->zone_size));
+ !btrfs_zoned_is_aligned(num_bytes, device->zone_info->zone_size));

path = btrfs_alloc_path();
if (!path)
@@ -5111,8 +5111,8 @@ static void init_alloc_chunk_ctl_policy_zoned(

ctl->max_stripe_size = zone_size;
if (type & BTRFS_BLOCK_GROUP_DATA) {
- ctl->max_chunk_size = round_down(BTRFS_MAX_DATA_CHUNK_SIZE,
- zone_size);
+ ctl->max_chunk_size = btrfs_zoned_rounddown(
+ BTRFS_MAX_DATA_CHUNK_SIZE, zone_size);
} else if (type & BTRFS_BLOCK_GROUP_METADATA) {
ctl->max_chunk_size = ctl->max_stripe_size;
} else if (type & BTRFS_BLOCK_GROUP_SYSTEM) {
@@ -5124,9 +5124,10 @@ static void init_alloc_chunk_ctl_policy_zoned(
}

/* We don't want a chunk larger than 10% of writable space */
- limit = max(round_down(div_factor(fs_devices->total_rw_bytes, 1),
- zone_size),
- min_chunk_size);
+ limit = max(
+ btrfs_zoned_rounddown(div_factor(fs_devices->total_rw_bytes, 1),
+ zone_size),
+ min_chunk_size);
ctl->max_chunk_size = min(limit, ctl->max_chunk_size);
ctl->dev_extent_min = zone_size * ctl->dev_stripes;
}
@@ -6729,7 +6730,8 @@ static void submit_stripe_bio(struct btrfs_io_context *bioc,
*/
if (bio_op(bio) == REQ_OP_ZONE_APPEND) {
if (btrfs_dev_is_sequential(dev, physical)) {
- u64 zone_start = round_down(physical, fs_info->zone_size);
+ u64 zone_start = btrfs_zoned_rounddown(physical,
+ fs_info->zone_size);

bio->bi_iter.bi_sector = zone_start >> SECTOR_SHIFT;
} else {
@@ -8051,8 +8053,8 @@ static int verify_one_dev_extent(struct btrfs_fs_info *fs_info,
if (dev->zone_info) {
u64 zone_size = dev->zone_info->zone_size;

- if (!IS_ALIGNED(physical_offset, zone_size) ||
- !IS_ALIGNED(physical_len, zone_size)) {
+ if (!btrfs_zoned_is_aligned(physical_offset, zone_size) ||
+ !btrfs_zoned_is_aligned(physical_len, zone_size)) {
btrfs_err(fs_info,
"zoned: dev extent devid %llu physical offset %llu len %llu is not aligned to device zone",
devid, physical_offset, physical_len);
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 5be2ef7bb..3023c871e 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -177,13 +177,13 @@ static inline u32 sb_zone_number(struct block_device *bdev, int mirror)
static inline sector_t zone_start_sector(u32 zone_number,
struct block_device *bdev)
{
- return (sector_t)zone_number << ilog2(bdev_zone_sectors(bdev));
+ return zone_number * bdev_zone_sectors(bdev);
}

static inline u64 zone_start_physical(u32 zone_number,
struct btrfs_zoned_device_info *zone_info)
{
- return (u64)zone_number << zone_info->zone_size_shift;
+ return zone_number * zone_info->zone_size;
}

/*
@@ -236,8 +236,8 @@ static int btrfs_get_dev_zones(struct btrfs_device *device, u64 pos,
if (zinfo->zone_cache) {
unsigned int i;

- ASSERT(IS_ALIGNED(pos, zinfo->zone_size));
- zno = pos >> zinfo->zone_size_shift;
+ ASSERT(btrfs_zoned_is_aligned(pos, zinfo->zone_size));
+ zno = bdev_zone_no(device->bdev, pos >> SECTOR_SHIFT);
/*
* We cannot report zones beyond the zone end. So, it is OK to
* cap *nr_zones to at the end.
@@ -409,9 +409,8 @@ int btrfs_get_dev_zone_info(struct btrfs_device *device, bool populate_cache)
}

nr_sectors = bdev_nr_sectors(bdev);
- zone_info->zone_size_shift = ilog2(zone_info->zone_size);
- zone_info->nr_zones = nr_sectors >> ilog2(zone_sectors);
- if (!IS_ALIGNED(nr_sectors, zone_sectors))
+ zone_info->nr_zones = bdev_zone_no(bdev, nr_sectors);
+ if (!btrfs_zoned_is_aligned(nr_sectors, zone_sectors))
zone_info->nr_zones++;

max_active_zones = bdev_max_active_zones(bdev);
@@ -823,10 +822,8 @@ int btrfs_sb_log_location_bdev(struct block_device *bdev, int mirror, int rw,
u64 *bytenr_ret)
{
struct blk_zone zones[BTRFS_NR_SB_LOG_ZONES];
- sector_t zone_sectors;
u32 sb_zone;
int ret;
- u8 zone_sectors_shift;
sector_t nr_sectors;
u32 nr_zones;

@@ -837,12 +834,10 @@ int btrfs_sb_log_location_bdev(struct block_device *bdev, int mirror, int rw,

ASSERT(rw == READ || rw == WRITE);

- zone_sectors = bdev_zone_sectors(bdev);
- if (!is_power_of_2(zone_sectors))
+ if (!is_power_of_2(bdev_zone_sectors(bdev)))
return -EINVAL;
- zone_sectors_shift = ilog2(zone_sectors);
nr_sectors = bdev_nr_sectors(bdev);
- nr_zones = nr_sectors >> zone_sectors_shift;
+ nr_zones = bdev_zone_no(bdev, nr_sectors);

sb_zone = sb_zone_number(bdev, mirror);
if (sb_zone + 1 >= nr_zones)
@@ -959,14 +954,12 @@ int btrfs_reset_sb_log_zones(struct block_device *bdev, int mirror)
{
sector_t zone_sectors;
sector_t nr_sectors;
- u8 zone_sectors_shift;
u32 sb_zone;
u32 nr_zones;

zone_sectors = bdev_zone_sectors(bdev);
- zone_sectors_shift = ilog2(zone_sectors);
nr_sectors = bdev_nr_sectors(bdev);
- nr_zones = nr_sectors >> zone_sectors_shift;
+ nr_zones = bdev_zone_no(bdev, nr_sectors);

sb_zone = sb_zone_number(bdev, mirror);
if (sb_zone + 1 >= nr_zones)
@@ -992,18 +985,17 @@ u64 btrfs_find_allocatable_zones(struct btrfs_device *device, u64 hole_start,
u64 hole_end, u64 num_bytes)
{
struct btrfs_zoned_device_info *zinfo = device->zone_info;
- const u8 shift = zinfo->zone_size_shift;
- u64 nzones = num_bytes >> shift;
+ u64 nzones = bdev_zone_no(device->bdev, num_bytes >> SECTOR_SHIFT);
u64 pos = hole_start;
u64 begin, end;
bool have_sb;
int i;

- ASSERT(IS_ALIGNED(hole_start, zinfo->zone_size));
- ASSERT(IS_ALIGNED(num_bytes, zinfo->zone_size));
+ ASSERT(btrfs_zoned_is_aligned(hole_start, zinfo->zone_size));
+ ASSERT(btrfs_zoned_is_aligned(num_bytes, zinfo->zone_size));

while (pos < hole_end) {
- begin = pos >> shift;
+ begin = bdev_zone_no(device->bdev, pos >> SECTOR_SHIFT);
end = begin + nzones;

if (end > zinfo->nr_zones)
@@ -1035,8 +1027,9 @@ u64 btrfs_find_allocatable_zones(struct btrfs_device *device, u64 hole_start,
if (!(pos + num_bytes <= sb_pos ||
sb_pos + BTRFS_SUPER_INFO_SIZE <= pos)) {
have_sb = true;
- pos = ALIGN(sb_pos + BTRFS_SUPER_INFO_SIZE,
- zinfo->zone_size);
+ pos = btrfs_zoned_roundup(
+ sb_pos + BTRFS_SUPER_INFO_SIZE,
+ zinfo->zone_size);
break;
}
}
@@ -1050,7 +1043,7 @@ u64 btrfs_find_allocatable_zones(struct btrfs_device *device, u64 hole_start,
static bool btrfs_dev_set_active_zone(struct btrfs_device *device, u64 pos)
{
struct btrfs_zoned_device_info *zone_info = device->zone_info;
- unsigned int zno = (pos >> zone_info->zone_size_shift);
+ unsigned int zno = bdev_zone_no(device->bdev, pos >> SECTOR_SHIFT);

/* We can use any number of zones */
if (zone_info->max_active_zones == 0)
@@ -1072,7 +1065,7 @@ static bool btrfs_dev_set_active_zone(struct btrfs_device *device, u64 pos)
static void btrfs_dev_clear_active_zone(struct btrfs_device *device, u64 pos)
{
struct btrfs_zoned_device_info *zone_info = device->zone_info;
- unsigned int zno = (pos >> zone_info->zone_size_shift);
+ unsigned int zno = bdev_zone_no(device->bdev, pos >> SECTOR_SHIFT);

/* We can use any number of zones */
if (zone_info->max_active_zones == 0)
@@ -1108,14 +1101,14 @@ int btrfs_reset_device_zone(struct btrfs_device *device, u64 physical,
int btrfs_ensure_empty_zones(struct btrfs_device *device, u64 start, u64 size)
{
struct btrfs_zoned_device_info *zinfo = device->zone_info;
- const u8 shift = zinfo->zone_size_shift;
- unsigned long begin = start >> shift;
- unsigned long end = (start + size) >> shift;
+ unsigned long begin = bdev_zone_no(device->bdev, start >> SECTOR_SHIFT);
+ unsigned long end =
+ bdev_zone_no(device->bdev, (start + size) >> SECTOR_SHIFT);
u64 pos;
int ret;

- ASSERT(IS_ALIGNED(start, zinfo->zone_size));
- ASSERT(IS_ALIGNED(size, zinfo->zone_size));
+ ASSERT(btrfs_zoned_is_aligned(start, zinfo->zone_size));
+ ASSERT(btrfs_zoned_is_aligned(size, zinfo->zone_size));

if (end > zinfo->nr_zones)
return -ERANGE;
@@ -1139,8 +1132,9 @@ int btrfs_ensure_empty_zones(struct btrfs_device *device, u64 start, u64 size)
/* Free regions should be empty */
btrfs_warn_in_rcu(
device->fs_info,
- "zoned: resetting device %s (devid %llu) zone %llu for allocation",
- rcu_str_deref(device->name), device->devid, pos >> shift);
+ "zoned: resetting device %s (devid %llu) zone %u for allocation",
+ rcu_str_deref(device->name), device->devid,
+ bdev_zone_no(device->bdev, pos >> SECTOR_SHIFT));
WARN_ON_ONCE(1);

ret = btrfs_reset_device_zone(device, pos, zinfo->zone_size,
@@ -1237,7 +1231,7 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache, bool new)
return 0;

/* Sanity check */
- if (!IS_ALIGNED(length, fs_info->zone_size)) {
+ if (!btrfs_zoned_is_aligned(length, fs_info->zone_size)) {
btrfs_err(fs_info,
"zoned: block group %llu len %llu unaligned to zone size %llu",
logical, length, fs_info->zone_size);
@@ -1325,7 +1319,7 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache, bool new)
* The group is mapped to a sequential zone. Get the zone write
* pointer to determine the allocation offset within the zone.
*/
- WARN_ON(!IS_ALIGNED(physical[i], fs_info->zone_size));
+ WARN_ON(!btrfs_zoned_is_aligned(physical[i], fs_info->zone_size));
nofs_flag = memalloc_nofs_save();
ret = btrfs_get_dev_zone(device, physical[i], &zone);
memalloc_nofs_restore(nofs_flag);
@@ -1351,10 +1345,12 @@ int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache, bool new)
switch (zone.cond) {
case BLK_ZONE_COND_OFFLINE:
case BLK_ZONE_COND_READONLY:
- btrfs_err(fs_info,
- "zoned: offline/readonly zone %llu on device %s (devid %llu)",
- physical[i] >> device->zone_info->zone_size_shift,
- rcu_str_deref(device->name), device->devid);
+ btrfs_err(
+ fs_info,
+ "zoned: offline/readonly zone %u on device %s (devid %llu)",
+ bdev_zone_no(device->bdev,
+ physical[i] >> SECTOR_SHIFT),
+ rcu_str_deref(device->name), device->devid);
alloc_offsets[i] = WP_MISSING_DEV;
break;
case BLK_ZONE_COND_EMPTY:
diff --git a/fs/btrfs/zoned.h b/fs/btrfs/zoned.h
index 694ab6d1e..b94ce4d1f 100644
--- a/fs/btrfs/zoned.h
+++ b/fs/btrfs/zoned.h
@@ -9,6 +9,7 @@
#include "disk-io.h"
#include "block-group.h"
#include "btrfs_inode.h"
+#include "misc.h"

#define BTRFS_DEFAULT_RECLAIM_THRESH (75)

@@ -18,7 +19,6 @@ struct btrfs_zoned_device_info {
* zoned block device.
*/
u64 zone_size;
- u8 zone_size_shift;
u32 nr_zones;
unsigned int max_active_zones;
atomic_t active_zones_left;
@@ -30,6 +30,36 @@ struct btrfs_zoned_device_info {
u32 sb_zone_location[BTRFS_SUPER_MIRROR_MAX];
};

+static inline bool btrfs_zoned_is_aligned(u64 pos, u64 zone_size)
+{
+ u64 remainder = 0;
+
+ if (is_power_of_two_u64(zone_size))
+ return IS_ALIGNED(pos, zone_size);
+
+ div64_u64_rem(pos, zone_size, &remainder);
+ return remainder == 0;
+}
+
+static inline u64 btrfs_zoned_roundup(u64 pos, u64 zone_size)
+{
+ if (is_power_of_two_u64(zone_size))
+ return ALIGN(pos, zone_size);
+
+ return div64_u64(pos + zone_size - 1, zone_size) * zone_size;
+}
+
+static inline u64 btrfs_zoned_rounddown(u64 pos, u64 zone_size)
+{
+ u64 remainder = 0;
+ if (is_power_of_two_u64(zone_size))
+ return round_down(pos, zone_size);
+
+ div64_u64_rem(pos, zone_size, &remainder);
+ pos -= remainder;
+ return pos;
+}
+
#ifdef CONFIG_BLK_DEV_ZONED
int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
struct blk_zone *zone);
@@ -253,7 +283,8 @@ static inline bool btrfs_dev_is_sequential(struct btrfs_device *device, u64 pos)
if (!zone_info)
return false;

- return test_bit(pos >> zone_info->zone_size_shift, zone_info->seq_zones);
+ return test_bit(bdev_zone_no(device->bdev, pos >> SECTOR_SHIFT),
+ zone_info->seq_zones);
}

static inline bool btrfs_dev_is_empty_zone(struct btrfs_device *device, u64 pos)
@@ -263,7 +294,8 @@ static inline bool btrfs_dev_is_empty_zone(struct btrfs_device *device, u64 pos)
if (!zone_info)
return true;

- return test_bit(pos >> zone_info->zone_size_shift, zone_info->empty_zones);
+ return test_bit(bdev_zone_no(device->bdev, pos >> SECTOR_SHIFT),
+ zone_info->empty_zones);
}

static inline void btrfs_dev_set_empty_zone_bit(struct btrfs_device *device,
@@ -275,7 +307,7 @@ static inline void btrfs_dev_set_empty_zone_bit(struct btrfs_device *device,
if (!zone_info)
return;

- zno = pos >> zone_info->zone_size_shift;
+ zno = bdev_zone_no(device->bdev, pos >> SECTOR_SHIFT);
if (set)
set_bit(zno, zone_info->empty_zones);
else
@@ -329,7 +361,8 @@ static inline bool btrfs_can_zone_reset(struct btrfs_device *device,
return false;

zone_size = device->zone_info->zone_size;
- if (!IS_ALIGNED(physical, zone_size) || !IS_ALIGNED(length, zone_size))
+ if (!btrfs_zoned_is_aligned(physical, zone_size) ||
+ !btrfs_zoned_is_aligned(length, zone_size))
return false;

return true;
--
2.25.1