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      1 /*
      2  * CDDL HEADER START
      3  *
      4  * The contents of this file are subject to the terms of the
      5  * Common Development and Distribution License (the "License").
      6  * You may not use this file except in compliance with the License.
      7  *
      8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
      9  * or http://www.opensolaris.org/os/licensing.
     10  * See the License for the specific language governing permissions
     11  * and limitations under the License.
     12  *
     13  * When distributing Covered Code, include this CDDL HEADER in each
     14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
     15  * If applicable, add the following below this CDDL HEADER, with the
     16  * fields enclosed by brackets "[]" replaced with your own identifying
     17  * information: Portions Copyright [yyyy] [name of copyright owner]
     18  *
     19  * CDDL HEADER END
     20  */
     21 /*
     22  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
     23  * Copyright (c) 2011, 2015 by Delphix. All rights reserved.
     24  */
     25 
     26 #ifndef _SYS_VDEV_IMPL_H
     27 #define	_SYS_VDEV_IMPL_H
     28 
     29 #include <sys/avl.h>
     30 #include <sys/dmu.h>
     31 #include <sys/metaslab.h>
     32 #include <sys/nvpair.h>
     33 #include <sys/space_map.h>
     34 #include <sys/vdev.h>
     35 #include <sys/dkio.h>
     36 #include <sys/uberblock_impl.h>
     37 
     38 #ifdef	__cplusplus
     39 extern "C" {
     40 #endif
     41 
     42 /*
     43  * Virtual device descriptors.
     44  *
     45  * All storage pool operations go through the virtual device framework,
     46  * which provides data replication and I/O scheduling.
     47  */
     48 
     49 /*
     50  * Forward declarations that lots of things need.
     51  */
     52 typedef struct vdev_queue vdev_queue_t;
     53 typedef struct vdev_cache vdev_cache_t;
     54 typedef struct vdev_cache_entry vdev_cache_entry_t;
     55 
     56 extern int zfs_vdev_queue_depth_pct;
     57 extern uint32_t zfs_vdev_async_write_max_active;
     58 
     59 /*
     60  * Virtual device operations
     61  */
     62 typedef int	vdev_open_func_t(vdev_t *vd, uint64_t *size, uint64_t *max_size,
     63     uint64_t *logical_ashift, uint64_t *physical_ashift);
     64 typedef void	vdev_close_func_t(vdev_t *vd);
     65 typedef uint64_t vdev_asize_func_t(vdev_t *vd, uint64_t psize);
     66 typedef void	vdev_io_start_func_t(zio_t *zio);
     67 typedef void	vdev_io_done_func_t(zio_t *zio);
     68 typedef void	vdev_state_change_func_t(vdev_t *vd, int, int);
     69 typedef void	vdev_hold_func_t(vdev_t *vd);
     70 typedef void	vdev_rele_func_t(vdev_t *vd);
     71 
     72 typedef struct vdev_ops {
     73 	vdev_open_func_t		*vdev_op_open;
     74 	vdev_close_func_t		*vdev_op_close;
     75 	vdev_asize_func_t		*vdev_op_asize;
     76 	vdev_io_start_func_t		*vdev_op_io_start;
     77 	vdev_io_done_func_t		*vdev_op_io_done;
     78 	vdev_state_change_func_t	*vdev_op_state_change;
     79 	vdev_hold_func_t		*vdev_op_hold;
     80 	vdev_rele_func_t		*vdev_op_rele;
     81 	char				vdev_op_type[16];
     82 	boolean_t			vdev_op_leaf;
     83 } vdev_ops_t;
     84 
     85 /*
     86  * Virtual device properties
     87  */
     88 struct vdev_cache_entry {
     89 	char		*ve_data;
     90 	uint64_t	ve_offset;
     91 	uint64_t	ve_lastused;
     92 	avl_node_t	ve_offset_node;
     93 	avl_node_t	ve_lastused_node;
     94 	uint32_t	ve_hits;
     95 	uint16_t	ve_missed_update;
     96 	zio_t		*ve_fill_io;
     97 };
     98 
     99 struct vdev_cache {
    100 	avl_tree_t	vc_offset_tree;
    101 	avl_tree_t	vc_lastused_tree;
    102 	kmutex_t	vc_lock;
    103 };
    104 
    105 typedef struct vdev_queue_class {
    106 	uint32_t	vqc_active;
    107 
    108 	/*
    109 	 * Sorted by offset or timestamp, depending on if the queue is
    110 	 * LBA-ordered vs FIFO.
    111 	 */
    112 	avl_tree_t	vqc_queued_tree;
    113 } vdev_queue_class_t;
    114 
    115 struct vdev_queue {
    116 	vdev_t		*vq_vdev;
    117 	vdev_queue_class_t vq_class[ZIO_PRIORITY_NUM_QUEUEABLE];
    118 	avl_tree_t	vq_active_tree;
    119 	avl_tree_t	vq_read_offset_tree;
    120 	avl_tree_t	vq_write_offset_tree;
    121 	uint64_t	vq_last_offset;
    122 	hrtime_t	vq_io_complete_ts; /* time last i/o completed */
    123 	kmutex_t	vq_lock;
    124 	uint64_t	vq_lastoffset;
    125 };
    126 
    127 /*
    128  * Virtual device descriptor
    129  */
    130 struct vdev {
    131 	/*
    132 	 * Common to all vdev types.
    133 	 */
    134 	uint64_t	vdev_id;	/* child number in vdev parent	*/
    135 	uint64_t	vdev_guid;	/* unique ID for this vdev	*/
    136 	uint64_t	vdev_guid_sum;	/* self guid + all child guids	*/
    137 	uint64_t	vdev_orig_guid;	/* orig. guid prior to remove	*/
    138 	uint64_t	vdev_asize;	/* allocatable device capacity	*/
    139 	uint64_t	vdev_min_asize;	/* min acceptable asize		*/
    140 	uint64_t	vdev_max_asize;	/* max acceptable asize		*/
    141 	uint64_t	vdev_ashift;	/* block alignment shift	*/
    142 	/*
    143 	 * Logical block alignment shift
    144 	 *
    145 	 * The smallest sized/aligned I/O supported by the device.
    146 	 */
    147 	uint64_t        vdev_logical_ashift;
    148 	/*
    149 	 * Physical block alignment shift
    150 	 *
    151 	 * The device supports logical I/Os with vdev_logical_ashift
    152 	 * size/alignment, but optimum performance will be achieved by
    153 	 * aligning/sizing requests to vdev_physical_ashift.  Smaller
    154 	 * requests may be inflated or incur device level read-modify-write
    155 	 * operations.
    156 	 *
    157 	 * May be 0 to indicate no preference (i.e. use vdev_logical_ashift).
    158          */
    159 	uint64_t        vdev_physical_ashift;
    160 	uint64_t	vdev_state;	/* see VDEV_STATE_* #defines	*/
    161 	uint64_t	vdev_prevstate;	/* used when reopening a vdev	*/
    162 	vdev_ops_t	*vdev_ops;	/* vdev operations		*/
    163 	spa_t		*vdev_spa;	/* spa for this vdev		*/
    164 	void		*vdev_tsd;	/* type-specific data		*/
    165 	vnode_t		*vdev_name_vp;	/* vnode for pathname		*/
    166 	vnode_t		*vdev_devid_vp;	/* vnode for devid		*/
    167 	vdev_t		*vdev_top;	/* top-level vdev		*/
    168 	vdev_t		*vdev_parent;	/* parent vdev			*/
    169 	vdev_t		**vdev_child;	/* array of children		*/
    170 	uint64_t	vdev_children;	/* number of children		*/
    171 	vdev_stat_t	vdev_stat;	/* virtual device statistics	*/
    172 	boolean_t	vdev_expanding;	/* expand the vdev?		*/
    173 	boolean_t	vdev_reopening;	/* reopen in progress?		*/
    174 	int		vdev_open_error; /* error on last open		*/
    175 	kthread_t	*vdev_open_thread; /* thread opening children	*/
    176 	uint64_t	vdev_crtxg;	/* txg when top-level was added */
    177 
    178 	/*
    179 	 * Top-level vdev state.
    180 	 */
    181 	uint64_t	vdev_ms_array;	/* metaslab array object	*/
    182 	uint64_t	vdev_ms_shift;	/* metaslab size shift		*/
    183 	uint64_t	vdev_ms_count;	/* number of metaslabs		*/
    184 	metaslab_group_t *vdev_mg;	/* metaslab group		*/
    185 	metaslab_t	**vdev_ms;	/* metaslab array		*/
    186 	txg_list_t	vdev_ms_list;	/* per-txg dirty metaslab lists	*/
    187 	txg_list_t	vdev_dtl_list;	/* per-txg dirty DTL lists	*/
    188 	txg_node_t	vdev_txg_node;	/* per-txg dirty vdev linkage	*/
    189 	boolean_t	vdev_remove_wanted; /* async remove wanted?	*/
    190 	boolean_t	vdev_probe_wanted; /* async probe wanted?	*/
    191 	list_node_t	vdev_config_dirty_node; /* config dirty list	*/
    192 	list_node_t	vdev_state_dirty_node; /* state dirty list	*/
    193 	uint64_t	vdev_deflate_ratio; /* deflation ratio (x512)	*/
    194 	uint64_t	vdev_islog;	/* is an intent log device	*/
    195 	uint64_t	vdev_removing;	/* device is being removed?	*/
    196 	boolean_t	vdev_ishole;	/* is a hole in the namespace	*/
    197 	kmutex_t	vdev_queue_lock; /* protects vdev_queue_depth	*/
    198 	uint64_t	vdev_top_zap;
    199 
    200 	/*
    201 	 * The queue depth parameters determine how many async writes are
    202 	 * still pending (i.e. allocated by net yet issued to disk) per
    203 	 * top-level (vdev_async_write_queue_depth) and the maximum allowed
    204 	 * (vdev_max_async_write_queue_depth). These values only apply to
    205 	 * top-level vdevs.
    206 	 */
    207 	uint64_t	vdev_async_write_queue_depth;
    208 	uint64_t	vdev_max_async_write_queue_depth;
    209 
    210 	/*
    211 	 * Leaf vdev state.
    212 	 */
    213 	range_tree_t	*vdev_dtl[DTL_TYPES]; /* dirty time logs	*/
    214 	space_map_t	*vdev_dtl_sm;	/* dirty time log space map	*/
    215 	txg_node_t	vdev_dtl_node;	/* per-txg dirty DTL linkage	*/
    216 	uint64_t	vdev_dtl_object; /* DTL object			*/
    217 	uint64_t	vdev_psize;	/* physical device capacity	*/
    218 	uint64_t	vdev_wholedisk;	/* true if this is a whole disk */
    219 	uint64_t	vdev_offline;	/* persistent offline state	*/
    220 	uint64_t	vdev_faulted;	/* persistent faulted state	*/
    221 	uint64_t	vdev_degraded;	/* persistent degraded state	*/
    222 	uint64_t	vdev_removed;	/* persistent removed state	*/
    223 	uint64_t	vdev_resilver_txg; /* persistent resilvering state */
    224 	uint64_t	vdev_nparity;	/* number of parity devices for raidz */
    225 	char		*vdev_path;	/* vdev path (if any)		*/
    226 	char		*vdev_devid;	/* vdev devid (if any)		*/
    227 	char		*vdev_physpath;	/* vdev device path (if any)	*/
    228 	char		*vdev_fru;	/* physical FRU location	*/
    229 	uint64_t	vdev_not_present; /* not present during import	*/
    230 	uint64_t	vdev_unspare;	/* unspare when resilvering done */
    231 	boolean_t	vdev_nowritecache; /* true if flushwritecache failed */
    232 	boolean_t	vdev_notrim;	/* true if trim failed */
    233 	boolean_t	vdev_checkremove; /* temporary online test	*/
    234 	boolean_t	vdev_forcefault; /* force online fault		*/
    235 	boolean_t	vdev_splitting;	/* split or repair in progress  */
    236 	boolean_t	vdev_delayed_close; /* delayed device close?	*/
    237 	boolean_t	vdev_tmpoffline; /* device taken offline temporarily? */
    238 	boolean_t	vdev_detached;	/* device detached?		*/
    239 	boolean_t	vdev_cant_read;	/* vdev is failing all reads	*/
    240 	boolean_t	vdev_cant_write; /* vdev is failing all writes	*/
    241 	boolean_t	vdev_isspare;	/* was a hot spare		*/
    242 	boolean_t	vdev_isl2cache;	/* was a l2cache device		*/
    243 	vdev_queue_t	vdev_queue;	/* I/O deadline schedule queue	*/
    244 	vdev_cache_t	vdev_cache;	/* physical block cache		*/
    245 	spa_aux_vdev_t	*vdev_aux;	/* for l2cache and spares vdevs	*/
    246 	zio_t		*vdev_probe_zio; /* root of current probe	*/
    247 	vdev_aux_t	vdev_label_aux;	/* on-disk aux state		*/
    248 	struct trim_map	*vdev_trimmap;	/* map on outstanding trims	*/
    249 	uint16_t	vdev_rotation_rate; /* rotational rate of the media */
    250 #define	VDEV_RATE_UNKNOWN	0
    251 #define	VDEV_RATE_NON_ROTATING	1
    252 	uint64_t	vdev_leaf_zap;
    253 
    254 	/*
    255 	 * For DTrace to work in userland (libzpool) context, these fields must
    256 	 * remain at the end of the structure.  DTrace will use the kernel's
    257 	 * CTF definition for 'struct vdev', and since the size of a kmutex_t is
    258 	 * larger in userland, the offsets for the rest of the fields would be
    259 	 * incorrect.
    260 	 */
    261 	kmutex_t	vdev_dtl_lock;	/* vdev_dtl_{map,resilver}	*/
    262 	kmutex_t	vdev_stat_lock;	/* vdev_stat			*/
    263 	kmutex_t	vdev_probe_lock; /* protects vdev_probe_zio	*/
    264 };
    265 
    266 #define	VDEV_RAIDZ_MAXPARITY	3
    267 
    268 #define	VDEV_PAD_SIZE		(8 << 10)
    269 /* 2 padding areas (vl_pad1 and vl_pad2) to skip */
    270 #define	VDEV_SKIP_SIZE		VDEV_PAD_SIZE * 2
    271 #define	VDEV_PHYS_SIZE		(112 << 10)
    272 #define	VDEV_UBERBLOCK_RING	(128 << 10)
    273 
    274 /* The largest uberblock we support is 8k. */
    275 #define	MAX_UBERBLOCK_SHIFT (13)
    276 #define	VDEV_UBERBLOCK_SHIFT(vd)	\
    277 	MIN(MAX((vd)->vdev_top->vdev_ashift, UBERBLOCK_SHIFT), \
    278 	    MAX_UBERBLOCK_SHIFT)
    279 #define	VDEV_UBERBLOCK_COUNT(vd)	\
    280 	(VDEV_UBERBLOCK_RING >> VDEV_UBERBLOCK_SHIFT(vd))
    281 #define	VDEV_UBERBLOCK_OFFSET(vd, n)	\
    282 	offsetof(vdev_label_t, vl_uberblock[(n) << VDEV_UBERBLOCK_SHIFT(vd)])
    283 #define	VDEV_UBERBLOCK_SIZE(vd)		(1ULL << VDEV_UBERBLOCK_SHIFT(vd))
    284 
    285 typedef struct vdev_phys {
    286 	char		vp_nvlist[VDEV_PHYS_SIZE - sizeof (zio_eck_t)];
    287 	zio_eck_t	vp_zbt;
    288 } vdev_phys_t;
    289 
    290 typedef struct vdev_label {
    291 	char		vl_pad1[VDEV_PAD_SIZE];			/*  8K */
    292 	char		vl_pad2[VDEV_PAD_SIZE];			/*  8K */
    293 	vdev_phys_t	vl_vdev_phys;				/* 112K	*/
    294 	char		vl_uberblock[VDEV_UBERBLOCK_RING];	/* 128K	*/
    295 } vdev_label_t;							/* 256K total */
    296 
    297 /*
    298  * vdev_dirty() flags
    299  */
    300 #define	VDD_METASLAB	0x01
    301 #define	VDD_DTL		0x02
    302 
    303 /* Offset of embedded boot loader region on each label */
    304 #define	VDEV_BOOT_OFFSET	(2 * sizeof (vdev_label_t))
    305 /*
    306  * Size of embedded boot loader region on each label.
    307  * The total size of the first two labels plus the boot area is 4MB.
    308  */
    309 #define	VDEV_BOOT_SIZE		(7ULL << 19)			/* 3.5M */
    310 
    311 /*
    312  * Size of label regions at the start and end of each leaf device.
    313  */
    314 #define	VDEV_LABEL_START_SIZE	(2 * sizeof (vdev_label_t) + VDEV_BOOT_SIZE)
    315 #define	VDEV_LABEL_END_SIZE	(2 * sizeof (vdev_label_t))
    316 #define	VDEV_LABELS		4
    317 #define	VDEV_BEST_LABEL		VDEV_LABELS
    318 
    319 #define	VDEV_ALLOC_LOAD		0
    320 #define	VDEV_ALLOC_ADD		1
    321 #define	VDEV_ALLOC_SPARE	2
    322 #define	VDEV_ALLOC_L2CACHE	3
    323 #define	VDEV_ALLOC_ROOTPOOL	4
    324 #define	VDEV_ALLOC_SPLIT	5
    325 #define	VDEV_ALLOC_ATTACH	6
    326 
    327 /*
    328  * Allocate or free a vdev
    329  */
    330 extern vdev_t *vdev_alloc_common(spa_t *spa, uint_t id, uint64_t guid,
    331     vdev_ops_t *ops);
    332 extern int vdev_alloc(spa_t *spa, vdev_t **vdp, nvlist_t *config,
    333     vdev_t *parent, uint_t id, int alloctype);
    334 extern void vdev_free(vdev_t *vd);
    335 
    336 /*
    337  * Add or remove children and parents
    338  */
    339 extern void vdev_add_child(vdev_t *pvd, vdev_t *cvd);
    340 extern void vdev_remove_child(vdev_t *pvd, vdev_t *cvd);
    341 extern void vdev_compact_children(vdev_t *pvd);
    342 extern vdev_t *vdev_add_parent(vdev_t *cvd, vdev_ops_t *ops);
    343 extern void vdev_remove_parent(vdev_t *cvd);
    344 
    345 /*
    346  * vdev sync load and sync
    347  */
    348 extern void vdev_load_log_state(vdev_t *nvd, vdev_t *ovd);
    349 extern boolean_t vdev_log_state_valid(vdev_t *vd);
    350 extern void vdev_load(vdev_t *vd);
    351 extern int vdev_dtl_load(vdev_t *vd);
    352 extern void vdev_sync(vdev_t *vd, uint64_t txg);
    353 extern void vdev_sync_done(vdev_t *vd, uint64_t txg);
    354 extern void vdev_dirty(vdev_t *vd, int flags, void *arg, uint64_t txg);
    355 extern void vdev_dirty_leaves(vdev_t *vd, int flags, uint64_t txg);
    356 
    357 /*
    358  * Available vdev types.
    359  */
    360 extern vdev_ops_t vdev_root_ops;
    361 extern vdev_ops_t vdev_mirror_ops;
    362 extern vdev_ops_t vdev_replacing_ops;
    363 extern vdev_ops_t vdev_raidz_ops;
    364 #if defined(__FreeBSD__) && defined(_KERNEL)
    365 extern vdev_ops_t vdev_geom_ops;
    366 #else
    367 extern vdev_ops_t vdev_disk_ops;
    368 #endif
    369 extern vdev_ops_t vdev_file_ops;
    370 extern vdev_ops_t vdev_missing_ops;
    371 extern vdev_ops_t vdev_hole_ops;
    372 extern vdev_ops_t vdev_spare_ops;
    373 
    374 /*
    375  * Common size functions
    376  */
    377 extern uint64_t vdev_default_asize(vdev_t *vd, uint64_t psize);
    378 extern uint64_t vdev_get_min_asize(vdev_t *vd);
    379 extern void vdev_set_min_asize(vdev_t *vd);
    380 
    381 /*
    382  * Global variables
    383  */
    384 /* zdb uses this tunable, so it must be declared here to make lint happy. */
    385 extern int zfs_vdev_cache_size;
    386 extern uint_t zfs_geom_probe_vdev_key;
    387 
    388 #ifdef illumos
    389 /*
    390  * The vdev_buf_t is used to translate between zio_t and buf_t, and back again.
    391  */
    392 typedef struct vdev_buf {
    393 	buf_t	vb_buf;		/* buffer that describes the io */
    394 	zio_t	*vb_io;		/* pointer back to the original zio_t */
    395 } vdev_buf_t;
    396 #endif
    397 
    398 #ifdef	__cplusplus
    399 }
    400 #endif
    401 
    402 #endif	/* _SYS_VDEV_IMPL_H */
    403