zoned.c
// SPDX-License-Identifier: GPL-2.0
#include <linux/bitops.h>
#include <linux/slab.h>
#include <linux/blkdev.h>
#include <linux/sched/mm.h>
#include "ctree.h"
#include "volumes.h"
#include "zoned.h"
#include "rcu-string.h"
#include "disk-io.h"
#include "block-group.h"
#include "transaction.h"
#include "dev-replace.h"
#include "space-info.h"
/* Maximum number of zones to report per blkdev_report_zones() call */
#define BTRFS_REPORT_NR_ZONES 4096
/* Invalid allocation pointer value for missing devices */
#define WP_MISSING_DEV ((u64)-1)
/* Pseudo write pointer value for conventional zone */
#define WP_CONVENTIONAL ((u64)-2)
/* Number of superblock log zones */
#define BTRFS_NR_SB_LOG_ZONES 2
static int copy_zone_info_cb(struct blk_zone *zone, unsigned int idx, void *data)
{
struct blk_zone *zones = data;
memcpy(&zones[idx], zone, sizeof(*zone));
return 0;
}
static int sb_write_pointer(struct block_device *bdev, struct blk_zone *zones,
u64 *wp_ret)
{
bool empty[BTRFS_NR_SB_LOG_ZONES];
bool full[BTRFS_NR_SB_LOG_ZONES];
sector_t sector;
ASSERT(zones[0].type != BLK_ZONE_TYPE_CONVENTIONAL &&
zones[1].type != BLK_ZONE_TYPE_CONVENTIONAL);
empty[0] = (zones[0].cond == BLK_ZONE_COND_EMPTY);
empty[1] = (zones[1].cond == BLK_ZONE_COND_EMPTY);
full[0] = (zones[0].cond == BLK_ZONE_COND_FULL);
full[1] = (zones[1].cond == BLK_ZONE_COND_FULL);
/*
* Possible states of log buffer zones
*
* Empty[0] In use[0] Full[0]
* Empty[1] * x 0
* In use[1] 0 x 0
* Full[1] 1 1 C
*
* Log position:
* *: Special case, no superblock is written
* 0: Use write pointer of zones[0]
* 1: Use write pointer of zones[1]
* C: Compare super blcoks from zones[0] and zones[1], use the latest
* one determined by generation
* x: Invalid state
*/
if (empty[0] && empty[1]) {
/* Special case to distinguish no superblock to read */
*wp_ret = zones[0].start << SECTOR_SHIFT;
return -ENOENT;
} else if (full[0] && full[1]) {
/* Compare two super blocks */
struct address_space *mapping = bdev->bd_inode->i_mapping;
struct page *page[BTRFS_NR_SB_LOG_ZONES];
struct btrfs_super_block *super[BTRFS_NR_SB_LOG_ZONES];
int i;
for (i = 0; i < BTRFS_NR_SB_LOG_ZONES; i++) {
u64 bytenr;
bytenr = ((zones[i].start + zones[i].len)
<< SECTOR_SHIFT) - BTRFS_SUPER_INFO_SIZE;
page[i] = read_cache_page_gfp(mapping,
bytenr >> PAGE_SHIFT, GFP_NOFS);
if (IS_ERR(page[i])) {
if (i == 1)
btrfs_release_disk_super(super[0]);
return PTR_ERR(page[i]);
}
super[i] = page_address(page[i]);
}
if (super[0]->generation > super[1]->generation)
sector = zones[1].start;
else
sector = zones[0].start;
for (i = 0; i < BTRFS_NR_SB_LOG_ZONES; i++)
btrfs_release_disk_super(super[i]);
} else if (!full[0] && (empty[1] || full[1])) {
sector = zones[0].wp;
} else if (full[0]) {
sector = zones[1].wp;
} else {
return -EUCLEAN;
}
*wp_ret = sector << SECTOR_SHIFT;
return 0;
}
/*
* The following zones are reserved as the circular buffer on ZONED btrfs.
* - The primary superblock: zones 0 and 1
* - The first copy: zones 16 and 17
* - The second copy: zones 1024 or zone at 256GB which is minimum, and
* the following one
*/
static inline u32 sb_zone_number(int shift, int mirror)
{
ASSERT(mirror < BTRFS_SUPER_MIRROR_MAX);
switch (mirror) {
case 0: return 0;
case 1: return 16;
case 2: return min_t(u64, btrfs_sb_offset(mirror) >> shift, 1024);
}
return 0;
}
/*
* Emulate blkdev_report_zones() for a non-zoned device. It slices up the block
* device into static sized chunks and fake a conventional zone on each of
* them.
*/
static int emulate_report_zones(struct btrfs_device *device, u64 pos,
struct blk_zone *zones, unsigned int nr_zones)
{
const sector_t zone_sectors = device->fs_info->zone_size >> SECTOR_SHIFT;
sector_t bdev_size = bdev_nr_sectors(device->bdev);
unsigned int i;
pos >>= SECTOR_SHIFT;
for (i = 0; i < nr_zones; i++) {
zones[i].start = i * zone_sectors + pos;
zones[i].len = zone_sectors;
zones[i].capacity = zone_sectors;
zones[i].wp = zones[i].start + zone_sectors;
zones[i].type = BLK_ZONE_TYPE_CONVENTIONAL;
zones[i].cond = BLK_ZONE_COND_NOT_WP;
if (zones[i].wp >= bdev_size) {
i++;
break;
}
}
return i;
}
static int btrfs_get_dev_zones(struct btrfs_device *device, u64 pos,
struct blk_zone *zones, unsigned int *nr_zones)
{
int ret;
if (!*nr_zones)
return 0;
if (!bdev_is_zoned(device->bdev)) {
ret = emulate_report_zones(device, pos, zones, *nr_zones);
*nr_zones = ret;
return 0;
}
ret = blkdev_report_zones(device->bdev, pos >> SECTOR_SHIFT, *nr_zones,
copy_zone_info_cb, zones);
if (ret < 0) {
btrfs_err_in_rcu(device->fs_info,
"zoned: failed to read zone %llu on %s (devid %llu)",
pos, rcu_str_deref(device->name),
device->devid);
return ret;
}
*nr_zones = ret;
if (!ret)
return -EIO;
return 0;
}
/* The emulated zone size is determined from the size of device extent */
static int calculate_emulated_zone_size(struct btrfs_fs_info *fs_info)
{
struct btrfs_path *path;
struct btrfs_root *root = fs_info->dev_root;
struct btrfs_key key;
struct extent_buffer *leaf;
struct btrfs_dev_extent *dext;
int ret = 0;
key.objectid = 1;
key.type = BTRFS_DEV_EXTENT_KEY;
key.offset = 0;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
if (ret < 0)
goto out;
if (path->slots[0] >= btrfs_header_nritems(path->nodes[0])) {
ret = btrfs_next_item(root, path);
if (ret < 0)
goto out;
/* No dev extents at all? Not good */
if (ret > 0) {
ret = -EUCLEAN;
goto out;
}
}
leaf = path->nodes[0];
dext = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_dev_extent);
fs_info->zone_size = btrfs_dev_extent_length(leaf, dext);
ret = 0;
out:
btrfs_free_path(path);
return ret;
}
int btrfs_get_dev_zone_info_all_devices(struct btrfs_fs_info *fs_info)
{
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
struct btrfs_device *device;
int ret = 0;
/* fs_info->zone_size might not set yet. Use the incomapt flag here. */
if (!btrfs_fs_incompat(fs_info, ZONED))
return 0;
mutex_lock(&fs_devices->device_list_mutex);
list_for_each_entry(device, &fs_devices->devices, dev_list) {
/* We can skip reading of zone info for missing devices */
if (!device->bdev)
continue;
ret = btrfs_get_dev_zone_info(device);
if (ret)
break;
}
mutex_unlock(&fs_devices->device_list_mutex);
return ret;
}
int btrfs_get_dev_zone_info(struct btrfs_device *device)
{
struct btrfs_fs_info *fs_info = device->fs_info;
struct btrfs_zoned_device_info *zone_info = NULL;
struct block_device *bdev = device->bdev;
struct request_queue *queue = bdev_get_queue(bdev);
sector_t nr_sectors;
sector_t sector = 0;
struct blk_zone *zones = NULL;
unsigned int i, nreported = 0, nr_zones;
sector_t zone_sectors;
char *model, *emulated;
int ret;
/*
* Cannot use btrfs_is_zoned here, since fs_info::zone_size might not
* yet be set.
*/
if (!btrfs_fs_incompat(fs_info, ZONED))
return 0;
if (device->zone_info)
return 0;
zone_info = kzalloc(sizeof(*zone_info), GFP_KERNEL);
if (!zone_info)
return -ENOMEM;
if (!bdev_is_zoned(bdev)) {
if (!fs_info->zone_size) {
ret = calculate_emulated_zone_size(fs_info);
if (ret)
goto out;
}
ASSERT(fs_info->zone_size);
zone_sectors = fs_info->zone_size >> SECTOR_SHIFT;
} else {
zone_sectors = bdev_zone_sectors(bdev);
}
nr_sectors = bdev_nr_sectors(bdev);
/* Check if it's power of 2 (see is_power_of_2) */
ASSERT(zone_sectors != 0 && (zone_sectors & (zone_sectors - 1)) == 0);
zone_info->zone_size = zone_sectors << SECTOR_SHIFT;
zone_info->zone_size_shift = ilog2(zone_info->zone_size);
zone_info->max_zone_append_size =
(u64)queue_max_zone_append_sectors(queue) << SECTOR_SHIFT;
zone_info->nr_zones = nr_sectors >> ilog2(zone_sectors);
if (!IS_ALIGNED(nr_sectors, zone_sectors))
zone_info->nr_zones++;
zone_info->seq_zones = bitmap_zalloc(zone_info->nr_zones, GFP_KERNEL);
if (!zone_info->seq_zones) {
ret = -ENOMEM;
goto out;
}
zone_info->empty_zones = bitmap_zalloc(zone_info->nr_zones, GFP_KERNEL);
if (!zone_info->empty_zones) {
ret = -ENOMEM;
goto out;
}
zones = kcalloc(BTRFS_REPORT_NR_ZONES, sizeof(struct blk_zone), GFP_KERNEL);
if (!zones) {
ret = -ENOMEM;
goto out;
}
/* Get zones type */
while (sector < nr_sectors) {
nr_zones = BTRFS_REPORT_NR_ZONES;
ret = btrfs_get_dev_zones(device, sector << SECTOR_SHIFT, zones,
&nr_zones);
if (ret)
goto out;
for (i = 0; i < nr_zones; i++) {
if (zones[i].type == BLK_ZONE_TYPE_SEQWRITE_REQ)
__set_bit(nreported, zone_info->seq_zones);
if (zones[i].cond == BLK_ZONE_COND_EMPTY)
__set_bit(nreported, zone_info->empty_zones);
nreported++;
}
sector = zones[nr_zones - 1].start + zones[nr_zones - 1].len;
}
if (nreported != zone_info->nr_zones) {
btrfs_err_in_rcu(device->fs_info,
"inconsistent number of zones on %s (%u/%u)",
rcu_str_deref(device->name), nreported,
zone_info->nr_zones);
ret = -EIO;
goto out;
}
/* Validate superblock log */
nr_zones = BTRFS_NR_SB_LOG_ZONES;
for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
u32 sb_zone;
u64 sb_wp;
int sb_pos = BTRFS_NR_SB_LOG_ZONES * i;
sb_zone = sb_zone_number(zone_info->zone_size_shift, i);
if (sb_zone + 1 >= zone_info->nr_zones)
continue;
sector = sb_zone << (zone_info->zone_size_shift - SECTOR_SHIFT);
ret = btrfs_get_dev_zones(device, sector << SECTOR_SHIFT,
&zone_info->sb_zones[sb_pos],
&nr_zones);
if (ret)
goto out;
if (nr_zones != BTRFS_NR_SB_LOG_ZONES) {
btrfs_err_in_rcu(device->fs_info,
"zoned: failed to read super block log zone info at devid %llu zone %u",
device->devid, sb_zone);
ret = -EUCLEAN;
goto out;
}
/*
* If zones[0] is conventional, always use the beggining of the
* zone to record superblock. No need to validate in that case.
*/
if (zone_info->sb_zones[BTRFS_NR_SB_LOG_ZONES * i].type ==
BLK_ZONE_TYPE_CONVENTIONAL)
continue;
ret = sb_write_pointer(device->bdev,
&zone_info->sb_zones[sb_pos], &sb_wp);
if (ret != -ENOENT && ret) {
btrfs_err_in_rcu(device->fs_info,
"zoned: super block log zone corrupted devid %llu zone %u",
device->devid, sb_zone);
ret = -EUCLEAN;
goto out;
}
}
kfree(zones);
device->zone_info = zone_info;
switch (bdev_zoned_model(bdev)) {
case BLK_ZONED_HM:
model = "host-managed zoned";
emulated = "";
break;
case BLK_ZONED_HA:
model = "host-aware zoned";
emulated = "";
break;
case BLK_ZONED_NONE:
model = "regular";
emulated = "emulated ";
break;
default:
/* Just in case */
btrfs_err_in_rcu(fs_info, "zoned: unsupported model %d on %s",
bdev_zoned_model(bdev),
rcu_str_deref(device->name));
ret = -EOPNOTSUPP;
goto out_free_zone_info;
}
btrfs_info_in_rcu(fs_info,
"%s block device %s, %u %szones of %llu bytes",
model, rcu_str_deref(device->name), zone_info->nr_zones,
emulated, zone_info->zone_size);
return 0;
out:
kfree(zones);
out_free_zone_info:
bitmap_free(zone_info->empty_zones);
bitmap_free(zone_info->seq_zones);
kfree(zone_info);
device->zone_info = NULL;
return ret;
}
void btrfs_destroy_dev_zone_info(struct btrfs_device *device)
{
struct btrfs_zoned_device_info *zone_info = device->zone_info;
if (!zone_info)
return;
bitmap_free(zone_info->seq_zones);
bitmap_free(zone_info->empty_zones);
kfree(zone_info);
device->zone_info = NULL;
}
int btrfs_get_dev_zone(struct btrfs_device *device, u64 pos,
struct blk_zone *zone)
{
unsigned int nr_zones = 1;
int ret;
ret = btrfs_get_dev_zones(device, pos, zone, &nr_zones);
if (ret != 0 || !nr_zones)
return ret ? ret : -EIO;
return 0;
}
int btrfs_check_zoned_mode(struct btrfs_fs_info *fs_info)
{
struct btrfs_fs_devices *fs_devices = fs_info->fs_devices;
struct btrfs_device *device;
u64 zoned_devices = 0;
u64 nr_devices = 0;
u64 zone_size = 0;
u64 max_zone_append_size = 0;
const bool incompat_zoned = btrfs_fs_incompat(fs_info, ZONED);
int ret = 0;
/* Count zoned devices */
list_for_each_entry(device, &fs_devices->devices, dev_list) {
enum blk_zoned_model model;
if (!device->bdev)
continue;
model = bdev_zoned_model(device->bdev);
/*
* A Host-Managed zoned device must be used as a zoned device.
* A Host-Aware zoned device and a non-zoned devices can be
* treated as a zoned device, if ZONED flag is enabled in the
* superblock.
*/
if (model == BLK_ZONED_HM ||
(model == BLK_ZONED_HA && incompat_zoned) ||
(model == BLK_ZONED_NONE && incompat_zoned)) {
struct btrfs_zoned_device_info *zone_info =
device->zone_info;
zone_info = device->zone_info;
zoned_devices++;
if (!zone_size) {
zone_size = zone_info->zone_size;
} else if (zone_info->zone_size != zone_size) {
btrfs_err(fs_info,
"zoned: unequal block device zone sizes: have %llu found %llu",
device->zone_info->zone_size,
zone_size);
ret = -EINVAL;
goto out;
}
if (!max_zone_append_size ||
(zone_info->max_zone_append_size &&
zone_info->max_zone_append_size < max_zone_append_size))
max_zone_append_size =
zone_info->max_zone_append_size;
}
nr_devices++;
}
if (!zoned_devices && !incompat_zoned)
goto out;
if (!zoned_devices && incompat_zoned) {
/* No zoned block device found on ZONED filesystem */
btrfs_err(fs_info,
"zoned: no zoned devices found on a zoned filesystem");
ret = -EINVAL;
goto out;
}
if (zoned_devices && !incompat_zoned) {
btrfs_err(fs_info,
"zoned: mode not enabled but zoned device found");
ret = -EINVAL;
goto out;
}
if (zoned_devices != nr_devices) {
btrfs_err(fs_info,
"zoned: cannot mix zoned and regular devices");
ret = -EINVAL;
goto out;
}
/*
* stripe_size is always aligned to BTRFS_STRIPE_LEN in
* __btrfs_alloc_chunk(). Since we want stripe_len == zone_size,
* check the alignment here.
*/
if (!IS_ALIGNED(zone_size, BTRFS_STRIPE_LEN)) {
btrfs_err(fs_info,
"zoned: zone size %llu not aligned to stripe %u",
zone_size, BTRFS_STRIPE_LEN);
ret = -EINVAL;
goto out;
}
if (btrfs_fs_incompat(fs_info, MIXED_GROUPS)) {
btrfs_err(fs_info, "zoned: mixed block groups not supported");
ret = -EINVAL;
goto out;
}
fs_info->zone_size = zone_size;
fs_info->max_zone_append_size = max_zone_append_size;
fs_info->fs_devices->chunk_alloc_policy = BTRFS_CHUNK_ALLOC_ZONED;
/*
* Check mount options here, because we might change fs_info->zoned
* from fs_info->zone_size.
*/
ret = btrfs_check_mountopts_zoned(fs_info);
if (ret)
goto out;
btrfs_info(fs_info, "zoned mode enabled with zone size %llu", zone_size);
out:
return ret;
}
int btrfs_check_mountopts_zoned(struct btrfs_fs_info *info)
{
if (!btrfs_is_zoned(info))
return 0;
/*
* Space cache writing is not COWed. Disable that to avoid write errors
* in sequential zones.
*/
if (btrfs_test_opt(info, SPACE_CACHE)) {
btrfs_err(info, "zoned: space cache v1 is not supported");
return -EINVAL;
}
if (btrfs_test_opt(info, NODATACOW)) {
btrfs_err(info, "zoned: NODATACOW not supported");
return -EINVAL;
}
return 0;
}
static int sb_log_location(struct block_device *bdev, struct blk_zone *zones,
int rw, u64 *bytenr_ret)
{
u64 wp;
int ret;
if (zones[0].type == BLK_ZONE_TYPE_CONVENTIONAL) {
*bytenr_ret = zones[0].start << SECTOR_SHIFT;
return 0;
}
ret = sb_write_pointer(bdev, zones, &wp);
if (ret != -ENOENT && ret < 0)
return ret;
if (rw == WRITE) {
struct blk_zone *reset = NULL;
if (wp == zones[0].start << SECTOR_SHIFT)
reset = &zones[0];
else if (wp == zones[1].start << SECTOR_SHIFT)
reset = &zones[1];
if (reset && reset->cond != BLK_ZONE_COND_EMPTY) {
ASSERT(reset->cond == BLK_ZONE_COND_FULL);
ret = blkdev_zone_mgmt(bdev, REQ_OP_ZONE_RESET,
reset->start, reset->len,
GFP_NOFS);
if (ret)
return ret;
reset->cond = BLK_ZONE_COND_EMPTY;
reset->wp = reset->start;
}
} else if (ret != -ENOENT) {
/* For READ, we want the precious one */
if (wp == zones[0].start << SECTOR_SHIFT)
wp = (zones[1].start + zones[1].len) << SECTOR_SHIFT;
wp -= BTRFS_SUPER_INFO_SIZE;
}
*bytenr_ret = wp;
return 0;
}
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;
if (!bdev_is_zoned(bdev)) {
*bytenr_ret = btrfs_sb_offset(mirror);
return 0;
}
ASSERT(rw == READ || rw == WRITE);
zone_sectors = bdev_zone_sectors(bdev);
if (!is_power_of_2(zone_sectors))
return -EINVAL;
zone_sectors_shift = ilog2(zone_sectors);
nr_sectors = bdev_nr_sectors(bdev);
nr_zones = nr_sectors >> zone_sectors_shift;
sb_zone = sb_zone_number(zone_sectors_shift + SECTOR_SHIFT, mirror);
if (sb_zone + 1 >= nr_zones)
return -ENOENT;
ret = blkdev_report_zones(bdev, sb_zone << zone_sectors_shift,
BTRFS_NR_SB_LOG_ZONES, copy_zone_info_cb,
zones);
if (ret < 0)
return ret;
if (ret != BTRFS_NR_SB_LOG_ZONES)
return -EIO;
return sb_log_location(bdev, zones, rw, bytenr_ret);
}
int btrfs_sb_log_location(struct btrfs_device *device, int mirror, int rw,
u64 *bytenr_ret)
{
struct btrfs_zoned_device_info *zinfo = device->zone_info;
u32 zone_num;
/*
* For a zoned filesystem on a non-zoned block device, use the same
* super block locations as regular filesystem. Doing so, the super
* block can always be retrieved and the zoned flag of the volume
* detected from the super block information.
*/
if (!bdev_is_zoned(device->bdev)) {
*bytenr_ret = btrfs_sb_offset(mirror);
return 0;
}
zone_num = sb_zone_number(zinfo->zone_size_shift, mirror);
if (zone_num + 1 >= zinfo->nr_zones)
return -ENOENT;
return sb_log_location(device->bdev,
&zinfo->sb_zones[BTRFS_NR_SB_LOG_ZONES * mirror],
rw, bytenr_ret);
}
static inline bool is_sb_log_zone(struct btrfs_zoned_device_info *zinfo,
int mirror)
{
u32 zone_num;
if (!zinfo)
return false;
zone_num = sb_zone_number(zinfo->zone_size_shift, mirror);
if (zone_num + 1 >= zinfo->nr_zones)
return false;
if (!test_bit(zone_num, zinfo->seq_zones))
return false;
return true;
}
void btrfs_advance_sb_log(struct btrfs_device *device, int mirror)
{
struct btrfs_zoned_device_info *zinfo = device->zone_info;
struct blk_zone *zone;
if (!is_sb_log_zone(zinfo, mirror))
return;
zone = &zinfo->sb_zones[BTRFS_NR_SB_LOG_ZONES * mirror];
if (zone->cond != BLK_ZONE_COND_FULL) {
if (zone->cond == BLK_ZONE_COND_EMPTY)
zone->cond = BLK_ZONE_COND_IMP_OPEN;
zone->wp += (BTRFS_SUPER_INFO_SIZE >> SECTOR_SHIFT);
if (zone->wp == zone->start + zone->len)
zone->cond = BLK_ZONE_COND_FULL;
return;
}
zone++;
ASSERT(zone->cond != BLK_ZONE_COND_FULL);
if (zone->cond == BLK_ZONE_COND_EMPTY)
zone->cond = BLK_ZONE_COND_IMP_OPEN;
zone->wp += (BTRFS_SUPER_INFO_SIZE >> SECTOR_SHIFT);
if (zone->wp == zone->start + zone->len)
zone->cond = BLK_ZONE_COND_FULL;
}
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;
sb_zone = sb_zone_number(zone_sectors_shift + SECTOR_SHIFT, mirror);
if (sb_zone + 1 >= nr_zones)
return -ENOENT;
return blkdev_zone_mgmt(bdev, REQ_OP_ZONE_RESET,
sb_zone << zone_sectors_shift,
zone_sectors * BTRFS_NR_SB_LOG_ZONES, GFP_NOFS);
}
/**
* btrfs_find_allocatable_zones - find allocatable zones within a given region
*
* @device: the device to allocate a region on
* @hole_start: the position of the hole to allocate the region
* @num_bytes: size of wanted region
* @hole_end: the end of the hole
* @return: position of allocatable zones
*
* Allocatable region should not contain any superblock locations.
*/
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 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));
while (pos < hole_end) {
begin = pos >> shift;
end = begin + nzones;
if (end > zinfo->nr_zones)
return hole_end;
/* Check if zones in the region are all empty */
if (btrfs_dev_is_sequential(device, pos) &&
find_next_zero_bit(zinfo->empty_zones, end, begin) != end) {
pos += zinfo->zone_size;
continue;
}
have_sb = false;
for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
u32 sb_zone;
u64 sb_pos;
sb_zone = sb_zone_number(shift, i);
if (!(end <= sb_zone ||
sb_zone + BTRFS_NR_SB_LOG_ZONES <= begin)) {
have_sb = true;
pos = ((u64)sb_zone + BTRFS_NR_SB_LOG_ZONES) << shift;
break;
}
/* We also need to exclude regular superblock positions */
sb_pos = btrfs_sb_offset(i);
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);
break;
}
}
if (!have_sb)
break;
}
return pos;
}
int btrfs_reset_device_zone(struct btrfs_device *device, u64 physical,
u64 length, u64 *bytes)
{
int ret;
*bytes = 0;
ret = blkdev_zone_mgmt(device->bdev, REQ_OP_ZONE_RESET,
physical >> SECTOR_SHIFT, length >> SECTOR_SHIFT,
GFP_NOFS);
if (ret)
return ret;
*bytes = length;
while (length) {
btrfs_dev_set_zone_empty(device, physical);
physical += device->zone_info->zone_size;
length -= device->zone_info->zone_size;
}
return 0;
}
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;
u64 pos;
int ret;
ASSERT(IS_ALIGNED(start, zinfo->zone_size));
ASSERT(IS_ALIGNED(size, zinfo->zone_size));
if (end > zinfo->nr_zones)
return -ERANGE;
/* All the zones are conventional */
if (find_next_bit(zinfo->seq_zones, begin, end) == end)
return 0;
/* All the zones are sequential and empty */
if (find_next_zero_bit(zinfo->seq_zones, begin, end) == end &&
find_next_zero_bit(zinfo->empty_zones, begin, end) == end)
return 0;
for (pos = start; pos < start + size; pos += zinfo->zone_size) {
u64 reset_bytes;
if (!btrfs_dev_is_sequential(device, pos) ||
btrfs_dev_is_empty_zone(device, pos))
continue;
/* 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);
WARN_ON_ONCE(1);
ret = btrfs_reset_device_zone(device, pos, zinfo->zone_size,
&reset_bytes);
if (ret)
return ret;
}
return 0;
}
/*
* Calculate an allocation pointer from the extent allocation information
* for a block group consist of conventional zones. It is pointed to the
* end of the highest addressed extent in the block group as an allocation
* offset.
*/
static int calculate_alloc_pointer(struct btrfs_block_group *cache,
u64 *offset_ret)
{
struct btrfs_fs_info *fs_info = cache->fs_info;
struct btrfs_root *root = fs_info->extent_root;
struct btrfs_path *path;
struct btrfs_key key;
struct btrfs_key found_key;
int ret;
u64 length;
path = btrfs_alloc_path();
if (!path)
return -ENOMEM;
key.objectid = cache->start + cache->length;
key.type = 0;
key.offset = 0;
ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
/* We should not find the exact match */
if (!ret)
ret = -EUCLEAN;
if (ret < 0)
goto out;
ret = btrfs_previous_extent_item(root, path, cache->start);
if (ret) {
if (ret == 1) {
ret = 0;
*offset_ret = 0;
}
goto out;
}
btrfs_item_key_to_cpu(path->nodes[0], &found_key, path->slots[0]);
if (found_key.type == BTRFS_EXTENT_ITEM_KEY)
length = found_key.offset;
else
length = fs_info->nodesize;
if (!(found_key.objectid >= cache->start &&
found_key.objectid + length <= cache->start + cache->length)) {
ret = -EUCLEAN;
goto out;
}
*offset_ret = found_key.objectid + length - cache->start;
ret = 0;
out:
btrfs_free_path(path);
return ret;
}
int btrfs_load_block_group_zone_info(struct btrfs_block_group *cache, bool new)
{
struct btrfs_fs_info *fs_info = cache->fs_info;
struct extent_map_tree *em_tree = &fs_info->mapping_tree;
struct extent_map *em;
struct map_lookup *map;
struct btrfs_device *device;
u64 logical = cache->start;
u64 length = cache->length;
u64 physical = 0;
int ret;
int i;
unsigned int nofs_flag;
u64 *alloc_offsets = NULL;
u64 last_alloc = 0;
u32 num_sequential = 0, num_conventional = 0;
if (!btrfs_is_zoned(fs_info))
return 0;
/* Sanity check */
if (!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);
return -EIO;
}
/* Get the chunk mapping */
read_lock(&em_tree->lock);
em = lookup_extent_mapping(em_tree, logical, length);
read_unlock(&em_tree->lock);
if (!em)
return -EINVAL;
map = em->map_lookup;
alloc_offsets = kcalloc(map->num_stripes, sizeof(*alloc_offsets), GFP_NOFS);
if (!alloc_offsets) {
free_extent_map(em);
return -ENOMEM;
}
for (i = 0; i < map->num_stripes; i++) {
bool is_sequential;
struct blk_zone zone;
struct btrfs_dev_replace *dev_replace = &fs_info->dev_replace;
int dev_replace_is_ongoing = 0;
device = map->stripes[i].dev;
physical = map->stripes[i].physical;
if (device->bdev == NULL) {
alloc_offsets[i] = WP_MISSING_DEV;
continue;
}
is_sequential = btrfs_dev_is_sequential(device, physical);
if (is_sequential)
num_sequential++;
else
num_conventional++;
if (!is_sequential) {
alloc_offsets[i] = WP_CONVENTIONAL;
continue;
}
/*
* This zone will be used for allocation, so mark this zone
* non-empty.
*/
btrfs_dev_clear_zone_empty(device, physical);
down_read(&dev_replace->rwsem);
dev_replace_is_ongoing = btrfs_dev_replace_is_ongoing(dev_replace);
if (dev_replace_is_ongoing && dev_replace->tgtdev != NULL)
btrfs_dev_clear_zone_empty(dev_replace->tgtdev, physical);
up_read(&dev_replace->rwsem);
/*
* 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, fs_info->zone_size));
nofs_flag = memalloc_nofs_save();
ret = btrfs_get_dev_zone(device, physical, &zone);
memalloc_nofs_restore(nofs_flag);
if (ret == -EIO || ret == -EOPNOTSUPP) {
ret = 0;
alloc_offsets[i] = WP_MISSING_DEV;
continue;
} else if (ret) {
goto out;
}
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 >> device->zone_info->zone_size_shift,
rcu_str_deref(device->name), device->devid);
alloc_offsets[i] = WP_MISSING_DEV;
break;
case BLK_ZONE_COND_EMPTY:
alloc_offsets[i] = 0;
break;
case BLK_ZONE_COND_FULL:
alloc_offsets[i] = fs_info->zone_size;
break;
default:
/* Partially used zone */
alloc_offsets[i] =
((zone.wp - zone.start) << SECTOR_SHIFT);
break;
}
}
if (num_sequential > 0)
cache->seq_zone = true;
if (num_conventional > 0) {
/*
* Avoid calling calculate_alloc_pointer() for new BG. It
* is no use for new BG. It must be always 0.
*
* Also, we have a lock chain of extent buffer lock ->
* chunk mutex. For new BG, this function is called from
* btrfs_make_block_group() which is already taking the
* chunk mutex. Thus, we cannot call
* calculate_alloc_pointer() which takes extent buffer
* locks to avoid deadlock.
*/
if (new) {
cache->alloc_offset = 0;
goto out;
}
ret = calculate_alloc_pointer(cache, &last_alloc);
if (ret || map->num_stripes == num_conventional) {
if (!ret)
cache->alloc_offset = last_alloc;
else
btrfs_err(fs_info,
"zoned: failed to determine allocation offset of bg %llu",
cache->start);
goto out;
}
}
switch (map->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
case 0: /* single */
cache->alloc_offset = alloc_offsets[0];
break;
case BTRFS_BLOCK_GROUP_DUP:
case BTRFS_BLOCK_GROUP_RAID1:
case BTRFS_BLOCK_GROUP_RAID0:
case BTRFS_BLOCK_GROUP_RAID10:
case BTRFS_BLOCK_GROUP_RAID5:
case BTRFS_BLOCK_GROUP_RAID6:
/* non-single profiles are not supported yet */
default:
btrfs_err(fs_info, "zoned: profile %s not yet supported",
btrfs_bg_type_to_raid_name(map->type));
ret = -EINVAL;
goto out;
}
out:
/* An extent is allocated after the write pointer */
if (!ret && num_conventional && last_alloc > cache->alloc_offset) {
btrfs_err(fs_info,
"zoned: got wrong write pointer in BG %llu: %llu > %llu",
logical, last_alloc, cache->alloc_offset);
ret = -EIO;
}
if (!ret)
cache->meta_write_pointer = cache->alloc_offset + cache->start;
kfree(alloc_offsets);
free_extent_map(em);
return ret;
}
void btrfs_calc_zone_unusable(struct btrfs_block_group *cache)
{
u64 unusable, free;
if (!btrfs_is_zoned(cache->fs_info))
return;
WARN_ON(cache->bytes_super != 0);
unusable = cache->alloc_offset - cache->used;
free = cache->length - cache->alloc_offset;
/* We only need ->free_space in ALLOC_SEQ block groups */
cache->last_byte_to_unpin = (u64)-1;
cache->cached = BTRFS_CACHE_FINISHED;
cache->free_space_ctl->free_space = free;
cache->zone_unusable = unusable;
/* Should not have any excluded extents. Just in case, though */
btrfs_free_excluded_extents(cache);
}
void btrfs_redirty_list_add(struct btrfs_transaction *trans,
struct extent_buffer *eb)
{
struct btrfs_fs_info *fs_info = eb->fs_info;
if (!btrfs_is_zoned(fs_info) ||
btrfs_header_flag(eb, BTRFS_HEADER_FLAG_WRITTEN) ||
!list_empty(&eb->release_list))
return;
set_extent_buffer_dirty(eb);
set_extent_bits_nowait(&trans->dirty_pages, eb->start,
eb->start + eb->len - 1, EXTENT_DIRTY);
memzero_extent_buffer(eb, 0, eb->len);
set_bit(EXTENT_BUFFER_NO_CHECK, &eb->bflags);
spin_lock(&trans->releasing_ebs_lock);
list_add_tail(&eb->release_list, &trans->releasing_ebs);
spin_unlock(&trans->releasing_ebs_lock);
atomic_inc(&eb->refs);
}
void btrfs_free_redirty_list(struct btrfs_transaction *trans)
{
spin_lock(&trans->releasing_ebs_lock);
while (!list_empty(&trans->releasing_ebs)) {
struct extent_buffer *eb;
eb = list_first_entry(&trans->releasing_ebs,
struct extent_buffer, release_list);
list_del_init(&eb->release_list);
free_extent_buffer(eb);
}
spin_unlock(&trans->releasing_ebs_lock);
}
bool btrfs_use_zone_append(struct btrfs_inode *inode, struct extent_map *em)
{
struct btrfs_fs_info *fs_info = inode->root->fs_info;
struct btrfs_block_group *cache;
bool ret = false;
if (!btrfs_is_zoned(fs_info))
return false;
if (!fs_info->max_zone_append_size)
return false;
if (!is_data_inode(&inode->vfs_inode))
return false;
cache = btrfs_lookup_block_group(fs_info, em->block_start);
ASSERT(cache);
if (!cache)
return false;
ret = cache->seq_zone;
btrfs_put_block_group(cache);
return ret;
}
void btrfs_record_physical_zoned(struct inode *inode, u64 file_offset,
struct bio *bio)
{
struct btrfs_ordered_extent *ordered;
const u64 physical = bio->bi_iter.bi_sector << SECTOR_SHIFT;
if (bio_op(bio) != REQ_OP_ZONE_APPEND)
return;
ordered = btrfs_lookup_ordered_extent(BTRFS_I(inode), file_offset);
if (WARN_ON(!ordered))
return;
ordered->physical = physical;
ordered->disk = bio->bi_bdev->bd_disk;
ordered->partno = bio->bi_bdev->bd_partno;
btrfs_put_ordered_extent(ordered);
}
void btrfs_rewrite_logical_zoned(struct btrfs_ordered_extent *ordered)
{
struct btrfs_inode *inode = BTRFS_I(ordered->inode);
struct btrfs_fs_info *fs_info = inode->root->fs_info;
struct extent_map_tree *em_tree;
struct extent_map *em;
struct btrfs_ordered_sum *sum;
struct block_device *bdev;
u64 orig_logical = ordered->disk_bytenr;
u64 *logical = NULL;
int nr, stripe_len;
/* Zoned devices should not have partitions. So, we can assume it is 0 */
ASSERT(ordered->partno == 0);
bdev = bdgrab(ordered->disk->part0);
if (WARN_ON(!bdev))
return;
if (WARN_ON(btrfs_rmap_block(fs_info, orig_logical, bdev,
ordered->physical, &logical, &nr,
&stripe_len)))
goto out;
WARN_ON(nr != 1);
if (orig_logical == *logical)
goto out;
ordered->disk_bytenr = *logical;
em_tree = &inode->extent_tree;
write_lock(&em_tree->lock);
em = search_extent_mapping(em_tree, ordered->file_offset,
ordered->num_bytes);
em->block_start = *logical;
free_extent_map(em);
write_unlock(&em_tree->lock);
list_for_each_entry(sum, &ordered->list, list) {
if (*logical < orig_logical)
sum->bytenr -= orig_logical - *logical;
else
sum->bytenr += *logical - orig_logical;
}
out:
kfree(logical);
bdput(bdev);
}
bool btrfs_check_meta_write_pointer(struct btrfs_fs_info *fs_info,
struct extent_buffer *eb,
struct btrfs_block_group **cache_ret)
{
struct btrfs_block_group *cache;
bool ret = true;
if (!btrfs_is_zoned(fs_info))
return true;
cache = *cache_ret;
if (cache && (eb->start < cache->start ||
cache->start + cache->length <= eb->start)) {
btrfs_put_block_group(cache);
cache = NULL;
*cache_ret = NULL;
}
if (!cache)
cache = btrfs_lookup_block_group(fs_info, eb->start);
if (cache) {
if (cache->meta_write_pointer != eb->start) {
btrfs_put_block_group(cache);
cache = NULL;
ret = false;
} else {
cache->meta_write_pointer = eb->start + eb->len;
}
*cache_ret = cache;
}
return ret;
}
void btrfs_revert_meta_write_pointer(struct btrfs_block_group *cache,
struct extent_buffer *eb)
{
if (!btrfs_is_zoned(eb->fs_info) || !cache)
return;
ASSERT(cache->meta_write_pointer == eb->start + eb->len);
cache->meta_write_pointer = eb->start;
}
int btrfs_zoned_issue_zeroout(struct btrfs_device *device, u64 physical, u64 length)
{
if (!btrfs_dev_is_sequential(device, physical))
return -EOPNOTSUPP;
return blkdev_issue_zeroout(device->bdev, physical >> SECTOR_SHIFT,
length >> SECTOR_SHIFT, GFP_NOFS, 0);
}
static int read_zone_info(struct btrfs_fs_info *fs_info, u64 logical,
struct blk_zone *zone)
{
struct btrfs_bio *bbio = NULL;
u64 mapped_length = PAGE_SIZE;
unsigned int nofs_flag;
int nmirrors;
int i, ret;
ret = btrfs_map_sblock(fs_info, BTRFS_MAP_GET_READ_MIRRORS, logical,
&mapped_length, &bbio);
if (ret || !bbio || mapped_length < PAGE_SIZE) {
btrfs_put_bbio(bbio);
return -EIO;
}
if (bbio->map_type & BTRFS_BLOCK_GROUP_RAID56_MASK)
return -EINVAL;
nofs_flag = memalloc_nofs_save();
nmirrors = (int)bbio->num_stripes;
for (i = 0; i < nmirrors; i++) {
u64 physical = bbio->stripes[i].physical;
struct btrfs_device *dev = bbio->stripes[i].dev;
/* Missing device */
if (!dev->bdev)
continue;
ret = btrfs_get_dev_zone(dev, physical, zone);
/* Failing device */
if (ret == -EIO || ret == -EOPNOTSUPP)
continue;
break;
}
memalloc_nofs_restore(nofs_flag);
return ret;
}
/*
* Synchronize write pointer in a zone at @physical_start on @tgt_dev, by
* filling zeros between @physical_pos to a write pointer of dev-replace
* source device.
*/
int btrfs_sync_zone_write_pointer(struct btrfs_device *tgt_dev, u64 logical,
u64 physical_start, u64 physical_pos)
{
struct btrfs_fs_info *fs_info = tgt_dev->fs_info;
struct blk_zone zone;
u64 length;
u64 wp;
int ret;
if (!btrfs_dev_is_sequential(tgt_dev, physical_pos))
return 0;
ret = read_zone_info(fs_info, logical, &zone);
if (ret)
return ret;
wp = physical_start + ((zone.wp - zone.start) << SECTOR_SHIFT);
if (physical_pos == wp)
return 0;
if (physical_pos > wp)
return -EUCLEAN;
length = wp - physical_pos;
return btrfs_zoned_issue_zeroout(tgt_dev, physical_pos, length);
}
