Commit 44b6d585 authored by Artur Paszkiewicz's avatar Artur Paszkiewicz Committed by Jim Harris
Browse files

FTL: Add helper functions for superblock upgrade 



Adds extra functions which will be used during upgrade (changing
versions) of superblock metadata.

Signed-off-by: default avatarKozlowski Mateusz <mateusz.kozlowski@intel.com>
Signed-off-by: default avatarArtur Paszkiewicz <artur.paszkiewicz@intel.com>
Change-Id: I08642deaf509f613cc8b22043dcdded6c329daa9
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/13383


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Reviewed-by: default avatarJim Harris <james.r.harris@intel.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
parent 1bc356bb

lib/ftl/ftl_layout.h

+2 −0
Original line number Diff line number Diff line
@@ -81,6 +81,8 @@ struct ftl_layout_region_descriptor { 


	/* Number of blocks in FTL_BLOCK_SIZE unit */

	uint64_t blocks;



	struct ftl_superblock_md_region *sb_md_reg;

};



/* Data or metadata region on devices */

lib/ftl/ftl_sb.c

+284 −0
Original line number Diff line number Diff line
@@ -12,3 +12,287 @@ ftl_superblock_check_magic(struct ftl_superblock *sb) 
{

	return sb->header.magic == FTL_SUPERBLOCK_MAGIC;

}

bool

ftl_superblock_md_layout_is_empty(struct ftl_superblock *sb)

{

	return sb->md_layout_head.type == FTL_LAYOUT_REGION_TYPE_INVALID;

}



static bool

md_region_is_fixed(int reg_type)

{

	switch (reg_type) {

#ifdef SPDK_FTL_VSS_EMU

	case FTL_LAYOUT_REGION_TYPE_VSS:

#endif

	case FTL_LAYOUT_REGION_TYPE_SB:

	case FTL_LAYOUT_REGION_TYPE_SB_BASE:

	case FTL_LAYOUT_REGION_TYPE_DATA_BASE:

		return true;



	default:

		return false;

	}

}



static uint32_t

md_regions_count(void)

{

	uint32_t reg_cnt = 0, reg_type;



	for (reg_type = 0; reg_type < FTL_LAYOUT_REGION_TYPE_MAX; reg_type++) {

		if (md_region_is_fixed(reg_type)) {

			continue;

		}



		reg_cnt++;

	}

	return reg_cnt;

}



static bool

superblock_md_region_overflow(struct spdk_ftl_dev *dev, struct ftl_superblock_md_region *sb_reg)

{

	/* sb_reg is part of the sb structure - the pointer should be at a positive offset */

	if ((uintptr_t)sb_reg < (uintptr_t)dev->sb) {

		return true;

	}



	/* There's only a finite (FTL_SUPERBLOCK_SIZE) amount of space in the superblock. Make sure the region wholly fits in that space. */

	if ((uintptr_t)(sb_reg + 1) > ((uintptr_t)(dev->sb) + FTL_SUPERBLOCK_SIZE)) {

		return true;

	}



	/* Make sure the entry doesn't overflow the pointer value (probably overkill to check) */

	if ((uintptr_t)(sb_reg + 1) < (uintptr_t)sb_reg) {

		return true;

	}



	return false;

}



static int

superblock_md_layout_add(struct spdk_ftl_dev *dev, struct ftl_superblock_md_region *sb_reg,

			 uint32_t reg_type, uint32_t reg_version, uint64_t blk_offs, uint64_t blk_sz)

{

	if (superblock_md_region_overflow(dev, sb_reg)) {

		FTL_ERRLOG(dev, "Buffer overflow\n");

		return -EOVERFLOW;

	}



	sb_reg->type = reg_type;

	sb_reg->version = reg_version;

	sb_reg->blk_offs = blk_offs;

	sb_reg->blk_sz = blk_sz;

	return 0;

}



static int

superblock_md_layout_add_free(struct spdk_ftl_dev *dev, struct ftl_superblock_md_region **sb_reg,

			      uint32_t reg_type, uint32_t free_type, uint64_t total_blocks)

{

	struct ftl_layout *layout = &dev->layout;

	struct ftl_layout_region *reg = &layout->region[reg_type];

	uint64_t blks_left = total_blocks - reg->current.offset - reg->current.blocks;



	if (blks_left == 0) {

		return 0;

	}



	(*sb_reg)->df_next = ftl_df_get_obj_id(dev->sb, (*sb_reg) + 1);

	(*sb_reg) = (*sb_reg) + 1;



	if (superblock_md_layout_add(dev, *sb_reg, free_type, 0,

				     reg->current.offset + reg->current.blocks, blks_left)) {

		return -1;

	}



	(*sb_reg)->df_next = FTL_DF_OBJ_ID_INVALID;



	return 0;

}



int

ftl_superblock_md_layout_build(struct spdk_ftl_dev *dev)

{

	struct ftl_superblock *sb = dev->sb;

	struct ftl_layout *layout = &dev->layout;

	struct ftl_layout_region *reg;

	int n = 0;

	bool is_empty = ftl_superblock_md_layout_is_empty(dev->sb);

	struct ftl_superblock_md_region *sb_reg = &sb->md_layout_head;



	/* TODO: major upgrades: add all free regions being tracked

	 * For now SB MD layout must be empty - otherwise md free regions may be lost */

	assert(is_empty);



	for (; n < FTL_LAYOUT_REGION_TYPE_MAX;) {

		reg = &layout->region[n];

		if (md_region_is_fixed(reg->type)) {

			reg->current.sb_md_reg = NULL;

			n++;



			if (n >= FTL_LAYOUT_REGION_TYPE_MAX) {

				/* For VSS emulation the last layout type is a fixed region, we need to move back the list and end the list on previous entry */

				sb_reg--;

				break;

			}

			continue;

		}



		if (superblock_md_layout_add(dev, sb_reg, reg->type, reg->current.version,

					     reg->current.offset, reg->current.blocks)) {

			return -1;

		}

		reg->current.sb_md_reg = sb_reg;



		n++;

		if (n < FTL_LAYOUT_REGION_TYPE_MAX) {

			/* next region */

			sb_reg->df_next = ftl_df_get_obj_id(sb, sb_reg + 1);

			sb_reg++;

		}

	}



	/* terminate the list */

	sb_reg->df_next = FTL_DF_OBJ_ID_INVALID;



	/* create free_nvc/free_base regions on the first run */

	if (is_empty) {

		superblock_md_layout_add_free(dev, &sb_reg, FTL_LAYOUT_REGION_LAST_NVC,

					      FTL_LAYOUT_REGION_TYPE_FREE_NVC, layout->nvc.total_blocks);



		superblock_md_layout_add_free(dev, &sb_reg, FTL_LAYOUT_REGION_LAST_BASE,

					      FTL_LAYOUT_REGION_TYPE_FREE_BASE, layout->base.total_blocks);

	}



	return 0;

}



int

ftl_superblock_md_layout_load_all(struct spdk_ftl_dev *dev)

{

	struct ftl_superblock *sb = dev->sb;

	struct ftl_superblock_md_region *sb_reg = &sb->md_layout_head;

	struct ftl_layout *layout = &dev->layout;

	uint32_t regs_found = 0;



	for (int n = 0; n < FTL_LAYOUT_REGION_TYPE_MAX; n++) {

		if (md_region_is_fixed(sb_reg->type)) {

			continue;

		}



		layout->region[n].current.sb_md_reg = NULL;

		layout->region[n].prev = layout->region[n].current;

	}



	while (sb_reg->type != FTL_LAYOUT_REGION_TYPE_INVALID) {

		struct ftl_layout_region *reg;



		/* TODO: major upgrades: add free regions tracking */

		if (sb_reg->type == FTL_LAYOUT_REGION_TYPE_FREE_NVC ||

		    sb_reg->type == FTL_LAYOUT_REGION_TYPE_FREE_BASE) {

			goto next_sb_reg;

		}



		if (sb_reg->type >= FTL_LAYOUT_REGION_TYPE_MAX) {

			FTL_ERRLOG(dev, "Invalid MD region type found\n");

			return -1;

		}



		if (md_region_is_fixed(sb_reg->type)) {

			FTL_ERRLOG(dev, "Unsupported MD region type found\n");

			return -1;

		}



		reg = &layout->region[sb_reg->type];

		if (sb_reg->version == reg->current.version) {

			if (reg->current.sb_md_reg) {

				FTL_ERRLOG(dev, "Multiple/looping current regions found\n");

				return -1;

			}



			reg->current.offset = sb_reg->blk_offs;

			reg->current.blocks = sb_reg->blk_sz;

			reg->current.sb_md_reg = sb_reg;



			if (!reg->prev.sb_md_reg) {

				regs_found++;

			}

		} else {

			if (sb_reg->version > reg->current.version) {

				FTL_ERRLOG(dev, "Unknown region version found\n");

				return -1;

			}

			/*

			 * The metadata regions are kept as a linked list, it's therefore possible to have it corrupted and contain loops.

			 * If the prev region has already been updated to the oldest found version (see following comment/block) and we see

			 * the same version again, it's a loop and error.

			 */

			if (sb_reg->version == reg->prev.version) {

				FTL_ERRLOG(dev, "Multiple/looping prev regions found\n");

				return -1;

			}



			/*

			 * The following check is in preparation for major metadata upgrade.

			 * It's possible that a region will need to be increased in size. It will allocate an additional region in this case

			 * and upgrade each entries one by one. If in the middle of this upgrade process a dirty shutdown occurs, there will be

			 * multiple entries of the same metadata region in the superblock (old original and partially updated one). This will then

			 * effectively rollback the upgrade to the oldest found metadata section and start from the beginning.

			 */

			if (sb_reg->version < reg->prev.version) {

				if ((!reg->current.sb_md_reg) && (!reg->prev.sb_md_reg)) {

					regs_found++;

				}



				reg->prev.offset = sb_reg->blk_offs;

				reg->prev.blocks = sb_reg->blk_sz;

				reg->prev.version = sb_reg->version;

				reg->prev.sb_md_reg = sb_reg;

			}

		}



next_sb_reg:

		if (sb_reg->df_next == FTL_DF_OBJ_ID_INVALID) {

			break;

		}



		sb_reg = ftl_df_get_obj_ptr(sb, sb_reg->df_next);

		if (superblock_md_region_overflow(dev, sb_reg)) {

			FTL_ERRLOG(dev, "Buffer overflow\n");

			return -EOVERFLOW;

		}

	}



	if (regs_found != md_regions_count()) {

		FTL_ERRLOG(dev, "Missing regions\n");

		return -1;

	}



	return 0;

}



void

ftl_superblock_md_layout_dump(struct spdk_ftl_dev *dev)

{

	struct ftl_superblock *sb = dev->sb;

	struct ftl_superblock_md_region *sb_reg = &sb->md_layout_head;



	FTL_NOTICELOG(dev, "SB metadata layout:\n");

	while (sb_reg->type != FTL_LAYOUT_REGION_TYPE_INVALID) {

		FTL_NOTICELOG(dev,

			      "Region df:0x%"PRIx64" type:0x%"PRIx32" ver:%"PRIu32" blk_offs:0x%"PRIx64" blk_sz:0x%"PRIx64"\n",

			      ftl_df_get_obj_id(sb, sb_reg), sb_reg->type, sb_reg->version, sb_reg->blk_offs, sb_reg->blk_sz);



		if (sb_reg->df_next == FTL_DF_OBJ_ID_INVALID) {

			break;

		}



		sb_reg = ftl_df_get_obj_ptr(sb, sb_reg->df_next);

		if (superblock_md_region_overflow(dev, sb_reg)) {

			FTL_ERRLOG(dev, "Buffer overflow\n");

			return;

		}

	}

}

lib/ftl/ftl_sb.h

+8 −0
Original line number Diff line number Diff line
@@ -14,4 +14,12 @@ struct spdk_ftl_dev; 


bool ftl_superblock_check_magic(struct ftl_superblock *sb);



bool ftl_superblock_md_layout_is_empty(struct ftl_superblock *sb);



int ftl_superblock_md_layout_build(struct spdk_ftl_dev *dev);



int ftl_superblock_md_layout_load_all(struct spdk_ftl_dev *dev);



void ftl_superblock_md_layout_dump(struct spdk_ftl_dev *dev);



#endif /* FTL_SB_H */

lib/ftl/ftl_sb_common.h

+2 −0
Original line number Diff line number Diff line
@@ -8,6 +8,7 @@ 


#include "spdk/stdinc.h"

#include "utils/ftl_defs.h"

#include "utils/ftl_df.h"



/* Size of superblock on NV cache, make it bigger for future fields */

#define FTL_SUPERBLOCK_SIZE (128ULL * KiB)
@@ -45,6 +46,7 @@ struct ftl_superblock_md_region { 
	uint32_t		version;

	uint64_t		blk_offs;

	uint64_t		blk_sz;

	ftl_df_obj_id		df_next;

};



struct ftl_superblock_shm {

lib/ftl/mngt/ftl_mngt_md.c

+1 −0
Original line number Diff line number Diff line
@@ -373,6 +373,7 @@ ftl_mngt_init_default_sb(struct spdk_ftl_dev *dev, struct ftl_mngt_process *mngt 
	/* md layout isn't initialized yet.

	 * empty region list => all regions in the default location */

	sb->md_layout_head.type = FTL_LAYOUT_REGION_TYPE_INVALID;

	sb->md_layout_head.df_next = FTL_DF_OBJ_ID_INVALID;



	sb->header.crc = get_sb_crc(sb);