RE: [PATCH 1/2] f2fs: support zone capacity less than zone size

[Aravind Ramesh <Aravind.Ramesh@wdc.com>]

Hello Chao,

I have sent the second version of this patch, with below changes.
Have merged the 2 patches into one. 
Updated commit message with nvme-cli output, as you suggested.
Updated check_block_count().
Updated f2fs.rst.
Changed kvfree() to kfree().
Please see inline, regarding one comment on kfree().

Please let me know your feedback.

Thanks,
Aravind

> -----Original Message-----
> From: Aravind Ramesh
> Sent: Thursday, July 9, 2020 12:41 PM
> To: Chao Yu <yuchao0@huawei.com>; jaegeuk@kernel.org; linux-
> fsdevel@vger.kernel.org; linux-f2fs-devel@lists.sourceforge.net; hch@lst.de
> Cc: Damien Le Moal <Damien.LeMoal@wdc.com>; Niklas Cassel
> <Niklas.Cassel@wdc.com>; Matias Bjorling <Matias.Bjorling@wdc.com>
> Subject: RE: [PATCH 1/2] f2fs: support zone capacity less than zone size
> 
> Comments inline.
> 
> Thanks,
> Aravind
> 
> > -----Original Message-----
> > From: Chao Yu <yuchao0@huawei.com>
> > Sent: Thursday, July 9, 2020 12:35 PM
> > To: Aravind Ramesh <Aravind.Ramesh@wdc.com>; jaegeuk@kernel.org;
> > linux- fsdevel@vger.kernel.org;
> > linux-f2fs-devel@lists.sourceforge.net; hch@lst.de
> > Cc: Damien Le Moal <Damien.LeMoal@wdc.com>; Niklas Cassel
> > <Niklas.Cassel@wdc.com>; Matias Bjorling <Matias.Bjorling@wdc.com>
> > Subject: Re: [PATCH 1/2] f2fs: support zone capacity less than zone
> > size
> >
> > On 2020/7/9 13:31, Aravind Ramesh wrote:
> > > Please find my response inline.
> > >
> > > Thanks,
> > > Aravind
> > >
> > >> -----Original Message-----
> > >> From: Chao Yu <yuchao0@huawei.com>
> > >> Sent: Thursday, July 9, 2020 8:26 AM
> > >> To: Aravind Ramesh <Aravind.Ramesh@wdc.com>; jaegeuk@kernel.org;
> > >> linux- fsdevel@vger.kernel.org;
> > >> linux-f2fs-devel@lists.sourceforge.net; hch@lst.de
> > >> Cc: Damien Le Moal <Damien.LeMoal@wdc.com>; Niklas Cassel
> > >> <Niklas.Cassel@wdc.com>; Matias Bjorling <Matias.Bjorling@wdc.com>
> > >> Subject: Re: [PATCH 1/2] f2fs: support zone capacity less than zone
> > >> size
> > >>
> > >> On 2020/7/8 21:04, Aravind Ramesh wrote:
> > >>> Please find my response inline.
> > >>>
> > >>> Thanks,
> > >>> Aravind
> > > [snip..]
> > >>>>>>> diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index
> > >>>>>>> c35614d255e1..d2156f3f56a5 100644
> > >>>>>>> --- a/fs/f2fs/segment.c
> > >>>>>>> +++ b/fs/f2fs/segment.c
> > >>>>>>> @@ -4294,9 +4294,12 @@ static void init_free_segmap(struct
> > >>>>>>> f2fs_sb_info *sbi)  {
> > >>>>>>>  	unsigned int start;
> > >>>>>>>  	int type;
> > >>>>>>> +	struct seg_entry *sentry;
> > >>>>>>>
> > >>>>>>>  	for (start = 0; start < MAIN_SEGS(sbi); start++) {
> > >>>>>>> -		struct seg_entry *sentry = get_seg_entry(sbi, start);
> > >>>>>>> +		if (f2fs_usable_blks_in_seg(sbi, start) == 0)
> > >>>>>>
> > >>>>>> If usable blocks count is zero, shouldn't we update
> > >>>>>> SIT_I(sbi)->written_valid_blocks as we did when there is
> > >>>>>> partial usable block in
> > >>>> current segment?
> > >>>>> If usable_block_count is zero, then it is like a dead segment,
> > >>>>> all blocks in the segment lie after the zone-capacity in the
> > >>>>> zone. So there can never be
> > >>>> a valid written content on these segments, hence it is not updated.
> > >>>>> In the other case, when a segment start before the zone-capacity
> > >>>>> and it ends beyond zone-capacity, then there are some blocks
> > >>>>> before zone-capacity
> > >>>> which can be used, so they are accounted for.
> > >>>>
> > >>>> I'm thinking that for limit_free_user_blocks() function, it
> > >>>> assumes all unwritten blocks as potential reclaimable blocks,
> > >>>> however segment after zone-capacity should never be used or
> > >>>> reclaimable, it looks calculation could
> > >> be not correct here.
> > >>>>
> > >>> The sbi->user_block_count is updated with the total usable_blocks
> > >>> in the full file system during the formatting of the file system
> > >>> using mkfs.f2fs. Please see the f2fs-tools patch series that I
> > >>> have submitted along with
> > >> this patch set.
> > >>>
> > >>> So sbi->user_block_count reflects the actual number of usable
> > >>> blocks (i.e. total
> > >> blocks - unusable blocks).
> > >>
> > >> Alright, will check both kernel and f2fs-tools change again later.
> > >> :)
> > >>
> > >>>
> > >>>> static inline block_t limit_free_user_blocks(struct f2fs_sb_info *sbi) {
> > >>>> 	block_t reclaimable_user_blocks = sbi->user_block_count -
> > >>>> 		written_block_count(sbi);
> > >>>> 	return (long)(reclaimable_user_blocks * LIMIT_FREE_BLOCK) / 100;
> > >>>> }
> > >>>>
> > >>>> static inline bool has_enough_invalid_blocks(struct f2fs_sb_info *sbi) {
> > >>>> 	block_t invalid_user_blocks = sbi->user_block_count -
> > >>>> 					written_block_count(sbi);
> > >>>> 	/*
> > >>>> 	 * Background GC is triggered with the following conditions.
> > >>>> 	 * 1. There are a number of invalid blocks.
> > >>>> 	 * 2. There is not enough free space.
> > >>>> 	 */
> > >>>> 	if (invalid_user_blocks > limit_invalid_user_blocks(sbi) &&
> > >>>> 			free_user_blocks(sbi) < limit_free_user_blocks(sbi))
> > >>>>
> > >>>> -- In this condition, free_user_blocks() doesn't include segments
> > >>>> after zone-capacity, however limit_free_user_blocks() includes them.
> > >>> In the second patch of this patch set, free_user_blocks is updated
> > >>> to account for
> > >> the segments after zone-capacity.
> > >>> It basically gets the free segment(segments before zone capacity
> > >>> and
> > >>> free) block count and deducts the overprovision segment block count.
> > >>> It also
> > >> considers the spanning segments block count into account.
> > >>
> > >> Okay.
> > >>
> > >>>
> > >>>
> > >>>>
> > >>>> 		return true;
> > >>>> 	return false;
> > >>>> }
> > >>>>
> > >>>>
> > >>>>>>
> > >>>>>>> +			continue;
> > >>>>>>> +		sentry = get_seg_entry(sbi, start);
> > >>>>>>>  		if (!sentry->valid_blocks)
> > >>>>>>>  			__set_free(sbi, start);
> > >>>>>>>  		else
> > >>>>>>> @@ -4316,7 +4319,7 @@ static void init_dirty_segmap(struct
> > >>>>>>> f2fs_sb_info
> > >>>> *sbi)
> > >>>>>>>  	struct dirty_seglist_info *dirty_i = DIRTY_I(sbi);
> > >>>>>>>  	struct free_segmap_info *free_i = FREE_I(sbi);
> > >>>>>>>  	unsigned int segno = 0, offset = 0, secno;
> > >>>>>>> -	unsigned short valid_blocks;
> > >>>>>>> +	unsigned short valid_blocks, usable_blks_in_seg;
> > >>>>>>>  	unsigned short blks_per_sec = BLKS_PER_SEC(sbi);
> > >>>>>>>
> > >>>>>>>  	while (1) {
> > >>>>>>> @@ -4326,9 +4329,10 @@ static void init_dirty_segmap(struct
> > >>>>>>> f2fs_sb_info
> > >>>> *sbi)
> > >>>>>>>  			break;
> > >>>>>>>  		offset = segno + 1;
> > >>>>>>>  		valid_blocks = get_valid_blocks(sbi, segno, false);
> > >>>>>>> -		if (valid_blocks == sbi->blocks_per_seg || !valid_blocks)
> > >>>>>>> +		usable_blks_in_seg = f2fs_usable_blks_in_seg(sbi, segno);
> > >>>>>>> +		if (valid_blocks == usable_blks_in_seg || !valid_blocks)
> > >>>>>>
> > >>>>>> It needs to traverse .cur_valid_map bitmap to check whether
> > >>>>>> blocks in range of [0, usable_blks_in_seg] are all valid or
> > >>>>>> not, if there is at least one usable block in the range, segment should be
> dirty.
> > >>>>> For the segments which start and end before zone-capacity are
> > >>>>> just like any
> > >>>> normal segments.
> > >>>>> Segments which start after the zone-capacity are fully unusable
> > >>>>> and are marked as
> > >>>> used in the free_seg_bitmap, so these segments are never used.
> > >>>>> Segments which span across the zone-capacity have some unusable
> > >>>>> blocks. Even
> > >>>> when blocks from these segments are allocated/deallocated the
> > >>>> valid_blocks counter is incremented/decremented, reflecting the
> > >>>> current
> > >> valid_blocks count.
> > >>>>> Comparing valid_blocks count with usable_blocks count in the
> > >>>>> segment can
> > >>>> indicate if the segment is dirty or fully used.
> > >>>>
> > >>>> I thought that if there is one valid block locates in range of
> > >>>> [usable_blks_in_seg, blks_per_seg] (after zone-capacity), the
> > >>>> condition will be incorrect. That should never happen, right?
> > >>> Yes, this will never happen. All blocks after zone-capacity are never usable.
> > >>>>
> > >>>> If so, how about adjusting check_block_count() to do sanity check
> > >>>> on bitmap locates after zone-capacity to make sure there is no free slots
> there.
> > >>>
> > >>> Ok, I will add this check in check_block_count. It makes sense.
> > >>>
> > >>>>
> > >>>>> Sorry, but could you please share why cur_valid_map needs to be
> > >>>>> traversed
> > ?
> > >>>>>
> > >>>>>>
> > >>>>>> One question, if we select dirty segment which across
> > >>>>>> zone-capacity as opened segment (in curseg), how can we avoid
> > >>>>>> allocating usable block beyong zone-capacity in such segment
> > >>>>>> via
> > .cur_valid_map?
> > >>>>> For zoned devices, we have to allocate blocks sequentially, so
> > >>>>> it's always in LFS
> > >>>> manner it is allocated.
> > >>>>> The __has_curseg_space() checks for the usable blocks and stops
> > >>>>> allocating blocks
> > >>>> after zone-capacity.
> > >>>>
> > >>>> Oh, that was implemented in patch 2, I haven't checked that
> > >>>> patch...sorry, however, IMO, patch should be made to apply
> > >>>> independently, what if do allocation only after applying patch
> > >>>> 1..., do we need to
> > >> merge them into one?
> > >>> The patches were split keeping in mind that all data structure
> > >>> related and initialization Changes would go into patch 1 and IO
> > >>> path and GC related
> > >> changes in patch 2.
> > >>> But if you think, merging them to a single patch will be easier to
> > >>> review,
> > >>
> > >> Yes, please, it's not only about easier review, but also for better
> > >> maintenance of patches in upstream, otherwise, it's not possible to
> > >> apply, backport, revert one of two patches independently.
> > >>
> > >> I still didn't get the full picture of using such zns device which
> > >> has configured zone- capacity, is it like?
> > >> 1. configure zone-capacity in zns device 2. mkfs.f2fs zns device 3.
> > >> mount zns device
> > >
> > > Zone-capacity is set by the device vendor. It could be same as
> > > zone-size or less than zone-size depending on vendor. It cannot be
> > > configured by
> > the user. So the step 1 is not possible.
> > > Since NVMe ZNS device zones are sequentially write only, we need
> > > another zoned device with Conventional zones or any normal block
> > > device for the
> > metadata operations of F2fs.
> > > I have provided some more explanation in the cover letter of the
> > > kernel patch set
> > on this.
> > > Step 2 is mkfs.f2fs zns device + block device (mkfs.f2fs -m -c
> > > /dev/nvme0n1 /dev/nullb1)
> > >
> > > A typical nvme-cli output of a zoned device shows zone start and
> > > capacity and
> > write pointer as below:
> > >
> > > SLBA: 0x0             WP: 0x0             Cap: 0x18800    State: EMPTY        Type:
> > SEQWRITE_REQ   Attrs: 0x0
> > > SLBA: 0x20000    WP: 0x20000    Cap: 0x18800    State: EMPTY        Type:
> > SEQWRITE_REQ   Attrs: 0x0
> > > SLBA: 0x40000    WP: 0x40000    Cap: 0x18800    State: EMPTY        Type:
> > SEQWRITE_REQ   Attrs: 0x0
> > >
> > > Here zone size is 64MB, capacity is 49MB, WP is at zone start as the
> > > zone is empty. Here for each zone, only zone start + 49MB is usable
> > > area, any lba/sector after 49MB cannot be read or written to, the
> > > drive will fail any attempts to read/write. So, the second zone
> > > starts at 64MB and is
> > usable till 113MB (64 + 49) and the range between 113 and 128MB is
> > again unusable. The next zone starts at 128MB, and so on.
> >
> > Thanks for the detailed explanation, more clear now. :)
> >
> > Could you please add above description into commit message of your kernel
> patch?
> > And also please consider to add simple introduction of f2fs zns device
> > support into f2fs.rst for our user?
> 
> Sure :).
> I will update f2fs.rst and patch commit message in V2.
> Thank you.
> >
> > Thanks,
> >
> > >
> > >>
> > >> Can we change zone-capacity dynamically after step 2? Or we should
> > >> run mkfs.f2fs again whenever update zone-capacity?
> > > User cannot change zone-capacity dynamically. It is device dependent.
> > >>
> > >> Thanks,
> > >>
> > >>> then I shall merge it and send it as one patch in V2, along with
> > >>> other suggestions
> > >> incorporated.
> > >>>
> > >>> Please let me know.
> > >>>>
> > >>>>>>
> > >>>>>>>  			continue;
> > >>>>>>> -		if (valid_blocks > sbi->blocks_per_seg) {
> > >>>>>>> +		if (valid_blocks > usable_blks_in_seg) {
> > >>>>>>>  			f2fs_bug_on(sbi, 1);
> > >>>>>>>  			continue;
> > >>>>>>>  		}
> > >>>>>>> @@ -4678,6 +4682,101 @@ int f2fs_check_write_pointer(struct
> > >>>>>>> f2fs_sb_info *sbi)
> > >>>>>>>
> > >>>>>>>  	return 0;
> > >>>>>>>  }
> > >>>>>>> +
> > >>>>>>> +static bool is_conv_zone(struct f2fs_sb_info *sbi, unsigned int
> zone_idx,
> > >>>>>>> +						unsigned int dev_idx)
> > >>>>>>> +{
> > >>>>>>> +	if (!bdev_is_zoned(FDEV(dev_idx).bdev))
> > >>>>>>> +		return true;
> > >>>>>>> +	return !test_bit(zone_idx, FDEV(dev_idx).blkz_seq); }
> > >>>>>>> +
> > >>>>>>> +/* Return the zone index in the given device */ static
> > >>>>>>> +unsigned int get_zone_idx(struct f2fs_sb_info *sbi, unsigned int secno,
> > >>>>>>> +					int dev_idx)
> > >>>>>>> +{
> > >>>>>>> +	block_t sec_start_blkaddr = START_BLOCK(sbi,
> > >>>>>>> +GET_SEG_FROM_SEC(sbi, secno));
> > >>>>>>> +
> > >>>>>>> +	return (sec_start_blkaddr - FDEV(dev_idx).start_blk) >>
> > >>>>>>> +						sbi->log_blocks_per_blkz;
> > }
> > >>>>>>> +
> > >>>>>>> +/*
> > >>>>>>> + * Return the usable segments in a section based on the
> > >>>>>>> +zone's
> > >>>>>>> + * corresponding zone capacity. Zone is equal to a section.
> > >>>>>>> + */
> > >>>>>>> +static inline unsigned int f2fs_usable_zone_segs_in_sec(
> > >>>>>>> +		struct f2fs_sb_info *sbi, unsigned int segno) {
> > >>>>>>> +	unsigned int dev_idx, zone_idx, unusable_segs_in_sec;
> > >>>>>>> +
> > >>>>>>> +	dev_idx = f2fs_target_device_index(sbi, START_BLOCK(sbi, segno));
> > >>>>>>> +	zone_idx = get_zone_idx(sbi, GET_SEC_FROM_SEG(sbi, segno),
> > >>>>>>> +dev_idx);
> > >>>>>>> +
> > >>>>>>> +	/* Conventional zone's capacity is always equal to zone size */
> > >>>>>>> +	if (is_conv_zone(sbi, zone_idx, dev_idx))
> > >>>>>>> +		return sbi->segs_per_sec;
> > >>>>>>> +
> > >>>>>>> +	/*
> > >>>>>>> +	 * If the zone_capacity_blocks array is NULL, then zone capacity
> > >>>>>>> +	 * is equal to the zone size for all zones
> > >>>>>>> +	 */
> > >>>>>>> +	if (!FDEV(dev_idx).zone_capacity_blocks)
> > >>>>>>> +		return sbi->segs_per_sec;
> > >>>>>>> +
> > >>>>>>> +	/* Get the segment count beyond zone capacity block */
> > >>>>>>> +	unusable_segs_in_sec = (sbi->blocks_per_blkz -
> > >>>>>>> +
> > >> 	FDEV(dev_idx).zone_capacity_blocks[zone_idx])
> > >>>>>>>>
> > >>>>>>> +				sbi->log_blocks_per_seg;
> > >>>>>>> +	return sbi->segs_per_sec - unusable_segs_in_sec; }
> > >>>>>>> +
> > >>>>>>> +/*
> > >>>>>>> + * Return the number of usable blocks in a segment. The
> > >>>>>>> +number of blocks
> > >>>>>>> + * returned is always equal to the number of blocks in a
> > >>>>>>> +segment for
> > >>>>>>> + * segments fully contained within a sequential zone capacity
> > >>>>>>> +or a
> > >>>>>>> + * conventional zone. For segments partially contained in a
> > >>>>>>> +sequential
> > >>>>>>> + * zone capacity, the number of usable blocks up to the zone
> > >>>>>>> +capacity
> > >>>>>>> + * is returned. 0 is returned in all other cases.
> > >>>>>>> + */
> > >>>>>>> +static inline unsigned int f2fs_usable_zone_blks_in_seg(
> > >>>>>>> +			struct f2fs_sb_info *sbi, unsigned int segno) {
> > >>>>>>> +	block_t seg_start, sec_start_blkaddr, sec_cap_blkaddr;
> > >>>>>>> +	unsigned int zone_idx, dev_idx, secno;
> > >>>>>>> +
> > >>>>>>> +	secno = GET_SEC_FROM_SEG(sbi, segno);
> > >>>>>>> +	seg_start = START_BLOCK(sbi, segno);
> > >>>>>>> +	dev_idx = f2fs_target_device_index(sbi, seg_start);
> > >>>>>>> +	zone_idx = get_zone_idx(sbi, secno, dev_idx);
> > >>>>>>> +
> > >>>>>>> +	/*
> > >>>>>>> +	 * Conventional zone's capacity is always equal to zone size,
> > >>>>>>> +	 * so, blocks per segment is unchanged.
> > >>>>>>> +	 */
> > >>>>>>> +	if (is_conv_zone(sbi, zone_idx, dev_idx))
> > >>>>>>> +		return sbi->blocks_per_seg;
> > >>>>>>> +
> > >>>>>>> +	if (!FDEV(dev_idx).zone_capacity_blocks)
> > >>>>>>> +		return sbi->blocks_per_seg;
> > >>>>>>> +
> > >>>>>>> +	sec_start_blkaddr = START_BLOCK(sbi, GET_SEG_FROM_SEC(sbi,
> > >> secno));
> > >>>>>>> +	sec_cap_blkaddr = sec_start_blkaddr +
> > >>>>>>> +
> > >> 	FDEV(dev_idx).zone_capacity_blocks[zone_idx];
> > >>>>>>> +
> > >>>>>>> +	/*
> > >>>>>>> +	 * If segment starts before zone capacity and spans beyond
> > >>>>>>> +	 * zone capacity, then usable blocks are from seg start to
> > >>>>>>> +	 * zone capacity. If the segment starts after the zone capacity,
> > >>>>>>> +	 * then there are no usable blocks.
> > >>>>>>> +	 */
> > >>>>>>> +	if (seg_start >= sec_cap_blkaddr)
> > >>>>>>> +		return 0;
> > >>>>>>> +	if (seg_start + sbi->blocks_per_seg > sec_cap_blkaddr)
> > >>>>>>> +		return sec_cap_blkaddr - seg_start;
> > >>>>>>> +
> > >>>>>>> +	return sbi->blocks_per_seg;
> > >>>>>>> +}
> > >>>>>>>  #else
> > >>>>>>>  int f2fs_fix_curseg_write_pointer(struct f2fs_sb_info *sbi)
> > >>>>>>> { @@
> > >>>>>>> -4688,7 +4787,36 @@ int f2fs_check_write_pointer(struct
> > >>>>>>> f2fs_sb_info
> > >>>>>>> *sbi)  {
> > >>>>>>>  	return 0;
> > >>>>>>>  }
> > >>>>>>> +
> > >>>>>>> +static inline unsigned int
> > >>>>>>> +f2fs_usable_zone_blks_in_seg(struct
> > >>>>>>> +f2fs_sb_info
> > >>>> *sbi,
> > >>>>>>> +							unsigned int
> > >> segno)
> > >>>>>>> +{
> > >>>>>>> +	return 0;
> > >>>>>>> +}
> > >>>>>>> +
> > >>>>>>> +static inline unsigned int
> > >>>>>>> +f2fs_usable_zone_segs_in_sec(struct
> > >>>>>>> +f2fs_sb_info
> > >>>> *sbi,
> > >>>>>>> +							unsigned int
> > >> segno)
> > >>>>>>> +{
> > >>>>>>> +	return 0;
> > >>>>>>> +}
> > >>>>>>>  #endif
> > >>>>>>> +unsigned int f2fs_usable_blks_in_seg(struct f2fs_sb_info *sbi,
> > >>>>>>> +					unsigned int segno)
> > >>>>>>> +{
> > >>>>>>> +	if (f2fs_sb_has_blkzoned(sbi))
> > >>>>>>> +		return f2fs_usable_zone_blks_in_seg(sbi, segno);
> > >>>>>>> +
> > >>>>>>> +	return sbi->blocks_per_seg;
> > >>>>>>> +}
> > >>>>>>> +
> > >>>>>>> +unsigned int f2fs_usable_segs_in_sec(struct f2fs_sb_info *sbi,
> > >>>>>>> +					unsigned int segno)
> > >>>>>>> +{
> > >>>>>>> +	if (f2fs_sb_has_blkzoned(sbi))
> > >>>>>>> +		return f2fs_usable_zone_segs_in_sec(sbi, segno);
> > >>>>>>> +
> > >>>>>>> +	return sbi->segs_per_sec;
> > >>>>>>> +}
> > >>>>>>>
> > >>>>>>>  /*
> > >>>>>>>   * Update min, max modified time for cost-benefit GC
> > >>>>>>> algorithm diff --git a/fs/f2fs/segment.h b/fs/f2fs/segment.h
> > >>>>>>> index f261e3e6a69b..79b0dc33feaf 100644
> > >>>>>>> --- a/fs/f2fs/segment.h
> > >>>>>>> +++ b/fs/f2fs/segment.h
> > >>>>>>> @@ -411,6 +411,7 @@ static inline void __set_free(struct
> > >>>>>>> f2fs_sb_info *sbi,
> > >>>>>> unsigned int segno)
> > >>>>>>>  	unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);
> > >>>>>>>  	unsigned int start_segno = GET_SEG_FROM_SEC(sbi, secno);
> > >>>>>>>  	unsigned int next;
> > >>>>>>> +	unsigned int usable_segs = f2fs_usable_segs_in_sec(sbi,
> > >>>>>>> +segno);
> > >>>>>>>
> > >>>>>>>  	spin_lock(&free_i->segmap_lock);
> > >>>>>>>  	clear_bit(segno, free_i->free_segmap); @@ -418,7 +419,7 @@
> > >>>>>>> static inline void __set_free(struct f2fs_sb_info *sbi,
> > >>>>>>> unsigned int segno)
> > >>>>>>>
> > >>>>>>>  	next = find_next_bit(free_i->free_segmap,
> > >>>>>>>  			start_segno + sbi->segs_per_sec, start_segno);
> > >>>>>>> -	if (next >= start_segno + sbi->segs_per_sec) {
> > >>>>>>> +	if (next >= start_segno + usable_segs) {
> > >>>>>>>  		clear_bit(secno, free_i->free_secmap);
> > >>>>>>>  		free_i->free_sections++;
> > >>>>>>>  	}
> > >>>>>>> @@ -444,6 +445,7 @@ static inline void
> > >>>>>>> __set_test_and_free(struct f2fs_sb_info
> > >>>>>> *sbi,
> > >>>>>>>  	unsigned int secno = GET_SEC_FROM_SEG(sbi, segno);
> > >>>>>>>  	unsigned int start_segno = GET_SEG_FROM_SEC(sbi, secno);
> > >>>>>>>  	unsigned int next;
> > >>>>>>> +	unsigned int usable_segs = f2fs_usable_segs_in_sec(sbi,
> > >>>>>>> +segno);
> > >>>>>>>
> > >>>>>>>  	spin_lock(&free_i->segmap_lock);
> > >>>>>>>  	if (test_and_clear_bit(segno, free_i->free_segmap)) { @@
> > >>>>>>> -453,7
> > >>>>>>> +455,7 @@ static inline void __set_test_and_free(struct
> > >>>>>>> +f2fs_sb_info *sbi,
> > >>>>>>>  			goto skip_free;
> > >>>>>>>  		next = find_next_bit(free_i->free_segmap,
> > >>>>>>>  				start_segno + sbi->segs_per_sec,
> > start_segno);
> > >>>>>>> -		if (next >= start_segno + sbi->segs_per_sec) {
> > >>>>>>> +		if (next >= start_segno + usable_segs) {
> > >>>>>>>  			if (test_and_clear_bit(secno, free_i-
> > >free_secmap))
> > >>>>>>>  				free_i->free_sections++;
> > >>>>>>>  		}
> > >>>>>>> diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index
> > >>>>>>> 80cb7cd358f8..2686b07ae7eb 100644
> > >>>>>>> --- a/fs/f2fs/super.c
> > >>>>>>> +++ b/fs/f2fs/super.c
> > >>>>>>> @@ -1164,6 +1164,7 @@ static void destroy_device_list(struct
> > >>>>>>> f2fs_sb_info
> > >>>> *sbi)
> > >>>>>>>  		blkdev_put(FDEV(i).bdev, FMODE_EXCL);  #ifdef
> > >>>>>> CONFIG_BLK_DEV_ZONED
> > >>>>>>>  		kvfree(FDEV(i).blkz_seq);
> > >>>>>>> +		kvfree(FDEV(i).zone_capacity_blocks);
> > >>>>>>
> > >>>>>> Now, f2fs_kzalloc won't allocate vmalloc's memory, so it's safe
> > >>>>>> to use
> > kfree().
> > >>>>> Ok
> > >>>>>>
> > >>>>>>>  #endif
> > >>>>>>>  	}
> > >>>>>>>  	kvfree(sbi->devs);
> > >>>>>>> @@ -3039,13 +3040,26 @@ static int init_percpu_info(struct
> > >>>>>>> f2fs_sb_info *sbi)  }
> > >>>>>>>
> > >>>>>>>  #ifdef CONFIG_BLK_DEV_ZONED
> > >>>>>>> +
> > >>>>>>> +struct f2fs_report_zones_args {
> > >>>>>>> +	struct f2fs_dev_info *dev;
> > >>>>>>> +	bool zone_cap_mismatch;
> > >>>>>>> +};
> > >>>>>>> +
> > >>>>>>>  static int f2fs_report_zone_cb(struct blk_zone *zone, unsigned int idx,
> > >>>>>>> -			       void *data)
> > >>>>>>> +			      void *data)
> > >>>>>>>  {
> > >>>>>>> -	struct f2fs_dev_info *dev = data;
> > >>>>>>> +	struct f2fs_report_zones_args *rz_args = data;
> > >>>>>>> +
> > >>>>>>> +	if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL)
> > >>>>>>> +		return 0;
> > >>>>>>> +
> > >>>>>>> +	set_bit(idx, rz_args->dev->blkz_seq);
> > >>>>>>> +	rz_args->dev->zone_capacity_blocks[idx] = zone->capacity >>
> > >>>>>>> +
> > >> 	F2FS_LOG_SECTORS_PER_BLOCK;
> > >>>>>>> +	if (zone->len != zone->capacity && !rz_args->zone_cap_mismatch)
> > >>>>>>> +		rz_args->zone_cap_mismatch = true;
> > >>>>>>>
> > >>>>>>> -	if (zone->type != BLK_ZONE_TYPE_CONVENTIONAL)
> > >>>>>>> -		set_bit(idx, dev->blkz_seq);
> > >>>>>>>  	return 0;
> > >>>>>>>  }
> > >>>>>>>
> > >>>>>>> @@ -3053,6 +3067,7 @@ static int init_blkz_info(struct
> > >>>>>>> f2fs_sb_info *sbi, int devi)  {
> > >>>>>>>  	struct block_device *bdev = FDEV(devi).bdev;
> > >>>>>>>  	sector_t nr_sectors = bdev->bd_part->nr_sects;
> > >>>>>>> +	struct f2fs_report_zones_args rep_zone_arg;
> > >>>>>>>  	int ret;
> > >>>>>>>
> > >>>>>>>  	if (!f2fs_sb_has_blkzoned(sbi)) @@ -3078,12 +3093,26 @@
> > >>>>>>> static int init_blkz_info(struct f2fs_sb_info *sbi, int
> > >>>>>> devi)
> > >>>>>>>  	if (!FDEV(devi).blkz_seq)
> > >>>>>>>  		return -ENOMEM;
> > >>>>>>>
> > >>>>>>> -	/* Get block zones type */
> > >>>>>>> +	/* Get block zones type and zone-capacity */
> > >>>>>>> +	FDEV(devi).zone_capacity_blocks = f2fs_kzalloc(sbi,
> > >>>>>>> +					FDEV(devi).nr_blkz *
> > >> sizeof(block_t),
> > >>>>>>> +					GFP_KERNEL);
> > >>>>>>> +	if (!FDEV(devi).zone_capacity_blocks)
> > >>>>>>> +		return -ENOMEM;
> > >>>>>>> +
> > >>>>>>> +	rep_zone_arg.dev = &FDEV(devi);
> > >>>>>>> +	rep_zone_arg.zone_cap_mismatch = false;
> > >>>>>>> +
> > >>>>>>>  	ret = blkdev_report_zones(bdev, 0, BLK_ALL_ZONES,
> > f2fs_report_zone_cb,
> > >>>>>>> -				  &FDEV(devi));
> > >>>>>>> +				  &rep_zone_arg);
> > >>>>>>>  	if (ret < 0)
> > >>>>>>>  		return ret;
> > >>>>>>
> > >>>>>> Missed to call kfree(FDEV(devi).zone_capacity_blocks)?
> > >>>>> Thanks for catching it. Will free it here also.

This case is actually handled. If error is returned, the control goes to destroy_device_list()
and does a kfree() on it, so it's not needed here. 

> > >>>>>>
> > >>>>>>>
> > >>>>>>> +	if (!rep_zone_arg.zone_cap_mismatch) {
> > >>>>>>> +		kvfree(FDEV(devi).zone_capacity_blocks);
> > >>>>>>
> > >>>>>> Ditto, kfree().
> > >>>>> Ok.
> > >>>>>>
> > >>>>>> Thanks,
> > >>>>>>
> > >>>>>>> +		FDEV(devi).zone_capacity_blocks = NULL;
> > >>>>>>> +	}
> > >>>>>>> +
> > >>>>>>>  	return 0;
> > >>>>>>>  }
> > >>>>>>>  #endif
> > >>>>>>>
> > >>>>> .
> > >>>>>
> > >>> .
> > >>>
> > > .
> > >