kernel/fs/zfs/sys/vdev_impl.h

   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 struct abd;
  56
  57 extern int zfs_vdev_queue_depth_pct;
  58 extern uint32_t zfs_vdev_async_write_max_active;
  59
  60 /*
  61  * Virtual device operations
  62  */
  63 typedef int     vdev_open_func_t(vdev_t *vd, uint64_t *size, uint64_t *max_size,
  64     uint64_t *ashift);
  65 typedef void    vdev_close_func_t(vdev_t *vd);
  66 typedef uint64_t vdev_asize_func_t(vdev_t *vd, uint64_t psize);
  67 typedef void    vdev_io_start_func_t(zio_t *zio);
  68 typedef void    vdev_io_done_func_t(zio_t *zio);
  69 typedef void    vdev_state_change_func_t(vdev_t *vd, int, int);
  70 typedef void    vdev_hold_func_t(vdev_t *vd);
  71 typedef void    vdev_rele_func_t(vdev_t *vd);
  72
  73 typedef struct vdev_ops {
  74         vdev_open_func_t                *vdev_op_open;
  75         vdev_close_func_t               *vdev_op_close;
  76         vdev_asize_func_t               *vdev_op_asize;
  77         vdev_io_start_func_t            *vdev_op_io_start;
  78         vdev_io_done_func_t             *vdev_op_io_done;
  79         vdev_state_change_func_t        *vdev_op_state_change;
  80         vdev_hold_func_t                *vdev_op_hold;
  81         vdev_rele_func_t                *vdev_op_rele;
  82         char                            vdev_op_type[16];
  83         boolean_t                       vdev_op_leaf;
  84 } vdev_ops_t;
  85
  86 /*
  87  * Virtual device properties
  88  */
  89 struct vdev_cache_entry {
  90         struct abd      *ve_abd;
  91         uint64_t        ve_offset;
  92         uint64_t        ve_lastused;
  93         avl_node_t      ve_offset_node;
  94         avl_node_t      ve_lastused_node;
  95         uint32_t        ve_hits;
  96         uint16_t        ve_missed_update;
  97         zio_t           *ve_fill_io;
  98 };
  99
 100 struct vdev_cache {
 101         avl_tree_t      vc_offset_tree;
 102         avl_tree_t      vc_lastused_tree;
 103         kmutex_t        vc_lock;
 104 };
 105
 106 typedef struct vdev_queue_class {
 107         uint32_t        vqc_active;
 108
 109         /*
 110          * Sorted by offset or timestamp, depending on if the queue is
 111          * LBA-ordered vs FIFO.
 112          */
 113         avl_tree_t      vqc_queued_tree;
 114 } vdev_queue_class_t;
 115
 116 struct vdev_queue {
 117         vdev_t          *vq_vdev;
 118         vdev_queue_class_t vq_class[ZIO_PRIORITY_NUM_QUEUEABLE];
 119         avl_tree_t      vq_active_tree;
 120         avl_tree_t      vq_read_offset_tree;
 121         avl_tree_t      vq_write_offset_tree;
 122         uint64_t        vq_last_offset;
 123         hrtime_t        vq_io_complete_ts; /* time last i/o completed */
 124         kmutex_t        vq_lock;
 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         uint64_t        vdev_state;     /* see VDEV_STATE_* #defines    */
 143         uint64_t        vdev_prevstate; /* used when reopening a vdev   */
 144         vdev_ops_t      *vdev_ops;      /* vdev operations              */
 145         spa_t           *vdev_spa;      /* spa for this vdev            */
 146         void            *vdev_tsd;      /* type-specific data           */
 147         vnode_t         *vdev_name_vp;  /* vnode for pathname           */
 148         vnode_t         *vdev_devid_vp; /* vnode for devid              */
 149         vdev_t          *vdev_top;      /* top-level vdev               */
 150         vdev_t          *vdev_parent;   /* parent vdev                  */
 151         vdev_t          **vdev_child;   /* array of children            */
 152         uint64_t        vdev_children;  /* number of children           */
 153         vdev_stat_t     vdev_stat;      /* virtual device statistics    */
 154         boolean_t       vdev_expanding; /* expand the vdev?             */
 155         boolean_t       vdev_reopening; /* reopen in progress?          */
 156         int             vdev_open_error; /* error on last open          */
 157         kthread_t       *vdev_open_thread; /* thread opening children   */
 158         uint64_t        vdev_crtxg;     /* txg when top-level was added */
 159
 160         /*
 161          * Top-level vdev state.
 162          */
 163         uint64_t        vdev_ms_array;  /* metaslab array object        */
 164         uint64_t        vdev_ms_shift;  /* metaslab size shift          */
 165         uint64_t        vdev_ms_count;  /* number of metaslabs          */
 166         metaslab_group_t *vdev_mg;      /* metaslab group               */
 167         metaslab_t      **vdev_ms;      /* metaslab array               */
 168         txg_list_t      vdev_ms_list;   /* per-txg dirty metaslab lists */
 169         txg_list_t      vdev_dtl_list;  /* per-txg dirty DTL lists      */
 170         txg_node_t      vdev_txg_node;  /* per-txg dirty vdev linkage   */
 171         boolean_t       vdev_remove_wanted; /* async remove wanted?     */
 172         boolean_t       vdev_probe_wanted; /* async probe wanted?       */
 173         list_node_t     vdev_config_dirty_node; /* config dirty list    */
 174         list_node_t     vdev_state_dirty_node; /* state dirty list      */
 175         uint64_t        vdev_deflate_ratio; /* deflation ratio (x512)   */
 176         uint64_t        vdev_islog;     /* is an intent log device      */
 177         uint64_t        vdev_removing;  /* device is being removed?     */
 178         boolean_t       vdev_ishole;    /* is a hole in the namespace   */
 179         kmutex_t        vdev_queue_lock; /* protects vdev_queue_depth   */
 180         uint64_t        vdev_top_zap;
 181
 182         /*
 183          * The queue depth parameters determine how many async writes are
 184          * still pending (i.e. allocated by net yet issued to disk) per
 185          * top-level (vdev_async_write_queue_depth) and the maximum allowed
 186          * (vdev_max_async_write_queue_depth). These values only apply to
 187          * top-level vdevs.
 188          */
 189         uint64_t        vdev_async_write_queue_depth;
 190         uint64_t        vdev_max_async_write_queue_depth;
 191
 192         /*
 193          * Leaf vdev state.
 194          */
 195         range_tree_t    *vdev_dtl[DTL_TYPES]; /* dirty time logs        */
 196         space_map_t     *vdev_dtl_sm;   /* dirty time log space map     */
 197         txg_node_t      vdev_dtl_node;  /* per-txg dirty DTL linkage    */
 198         uint64_t        vdev_dtl_object; /* DTL object                  */
 199         uint64_t        vdev_psize;     /* physical device capacity     */
 200         uint64_t        vdev_wholedisk; /* true if this is a whole disk */
 201         uint64_t        vdev_offline;   /* persistent offline state     */
 202         uint64_t        vdev_faulted;   /* persistent faulted state     */
 203         uint64_t        vdev_degraded;  /* persistent degraded state    */
 204         uint64_t        vdev_removed;   /* persistent removed state     */
 205         uint64_t        vdev_resilver_txg; /* persistent resilvering state */
 206         uint64_t        vdev_nparity;   /* number of parity devices for raidz */
 207         char            *vdev_path;     /* vdev path (if any)           */
 208         char            *vdev_devid;    /* vdev devid (if any)          */
 209         char            *vdev_physpath; /* vdev device path (if any)    */
 210         char            *vdev_fru;      /* physical FRU location        */
 211         uint64_t        vdev_not_present; /* not present during import  */
 212         uint64_t        vdev_unspare;   /* unspare when resilvering done */
 213         boolean_t       vdev_nowritecache; /* true if flushwritecache failed */
 214         boolean_t       vdev_checkremove; /* temporary online test      */
 215         boolean_t       vdev_forcefault; /* force online fault          */
 216         boolean_t       vdev_splitting; /* split or repair in progress  */
 217         boolean_t       vdev_delayed_close; /* delayed device close?    */
 218         boolean_t       vdev_tmpoffline; /* device taken offline temporarily? */
 219         boolean_t       vdev_detached;  /* device detached?             */
 220         boolean_t       vdev_cant_read; /* vdev is failing all reads    */
 221         boolean_t       vdev_cant_write; /* vdev is failing all writes  */
 222         boolean_t       vdev_isspare;   /* was a hot spare              */
 223         boolean_t       vdev_isl2cache; /* was a l2cache device         */
 224         vdev_queue_t    vdev_queue;     /* I/O deadline schedule queue  */
 225         vdev_cache_t    vdev_cache;     /* physical block cache         */
 226         spa_aux_vdev_t  *vdev_aux;      /* for l2cache and spares vdevs */
 227         zio_t           *vdev_probe_zio; /* root of current probe       */
 228         vdev_aux_t      vdev_label_aux; /* on-disk aux state            */
 229         uint64_t        vdev_leaf_zap;
 230
 231         /*
 232          * For DTrace to work in userland (libzpool) context, these fields must
 233          * remain at the end of the structure.  DTrace will use the kernel's
 234          * CTF definition for 'struct vdev', and since the size of a kmutex_t is
 235          * larger in userland, the offsets for the rest of the fields would be
 236          * incorrect.
 237          */
 238         kmutex_t        vdev_dtl_lock;  /* vdev_dtl_{map,resilver}      */
 239         kmutex_t        vdev_stat_lock; /* vdev_stat                    */
 240         kmutex_t        vdev_probe_lock; /* protects vdev_probe_zio     */
 241 };
 242
 243 #define VDEV_RAIDZ_MAXPARITY    3
 244
 245 #define VDEV_PAD_SIZE           (8 << 10)
 246 /* 2 padding areas (vl_pad1 and vl_pad2) to skip */
 247 #define VDEV_SKIP_SIZE          VDEV_PAD_SIZE * 2
 248 #define VDEV_PHYS_SIZE          (112 << 10)
 249 #define VDEV_UBERBLOCK_RING     (128 << 10)
 250
 251 /* The largest uberblock we support is 8k. */
 252 #define MAX_UBERBLOCK_SHIFT (13)
 253 #define VDEV_UBERBLOCK_SHIFT(vd)        \
 254         MIN(MAX((vd)->vdev_top->vdev_ashift, UBERBLOCK_SHIFT), \
 255             MAX_UBERBLOCK_SHIFT)
 256 #define VDEV_UBERBLOCK_COUNT(vd)        \
 257         (VDEV_UBERBLOCK_RING >> VDEV_UBERBLOCK_SHIFT(vd))
 258 #define VDEV_UBERBLOCK_OFFSET(vd, n)    \
 259         offsetof(vdev_label_t, vl_uberblock[(n) << VDEV_UBERBLOCK_SHIFT(vd)])
 260 #define VDEV_UBERBLOCK_SIZE(vd)         (1ULL << VDEV_UBERBLOCK_SHIFT(vd))
 261
 262 typedef struct vdev_phys {
 263         char            vp_nvlist[VDEV_PHYS_SIZE - sizeof (zio_eck_t)];
 264         zio_eck_t       vp_zbt;
 265 } vdev_phys_t;
 266
 267 typedef struct vdev_label {
 268         char            vl_pad1[VDEV_PAD_SIZE];                 /*  8K */
 269         char            vl_pad2[VDEV_PAD_SIZE];                 /*  8K */
 270         vdev_phys_t     vl_vdev_phys;                           /* 112K */
 271         char            vl_uberblock[VDEV_UBERBLOCK_RING];      /* 128K */
 272 } vdev_label_t;                                                 /* 256K total */
 273
 274 /*
 275  * vdev_dirty() flags
 276  */
 277 #define VDD_METASLAB    0x01
 278 #define VDD_DTL         0x02
 279
 280 /* Offset of embedded boot loader region on each label */
 281 #define VDEV_BOOT_OFFSET        (2 * sizeof (vdev_label_t))
 282 /*
 283  * Size of embedded boot loader region on each label.
 284  * The total size of the first two labels plus the boot area is 4MB.
 285  */
 286 #define VDEV_BOOT_SIZE          (7ULL << 19)                    /* 3.5M */
 287
 288 /*
 289  * Size of label regions at the start and end of each leaf device.
 290  */
 291 #define VDEV_LABEL_START_SIZE   (2 * sizeof (vdev_label_t) + VDEV_BOOT_SIZE)
 292 #define VDEV_LABEL_END_SIZE     (2 * sizeof (vdev_label_t))
 293 #define VDEV_LABELS             4
 294 #define VDEV_BEST_LABEL         VDEV_LABELS
 295
 296 #define VDEV_ALLOC_LOAD         0
 297 #define VDEV_ALLOC_ADD          1
 298 #define VDEV_ALLOC_SPARE        2
 299 #define VDEV_ALLOC_L2CACHE      3
 300 #define VDEV_ALLOC_ROOTPOOL     4
 301 #define VDEV_ALLOC_SPLIT        5
 302 #define VDEV_ALLOC_ATTACH       6
 303
 304 /*
 305  * Allocate or free a vdev
 306  */
 307 extern vdev_t *vdev_alloc_common(spa_t *spa, uint_t id, uint64_t guid,
 308     vdev_ops_t *ops);
 309 extern int vdev_alloc(spa_t *spa, vdev_t **vdp, nvlist_t *config,
 310     vdev_t *parent, uint_t id, int alloctype);
 311 extern void vdev_free(vdev_t *vd);
 312
 313 /*
 314  * Add or remove children and parents
 315  */
 316 extern void vdev_add_child(vdev_t *pvd, vdev_t *cvd);
 317 extern void vdev_remove_child(vdev_t *pvd, vdev_t *cvd);
 318 extern void vdev_compact_children(vdev_t *pvd);
 319 extern vdev_t *vdev_add_parent(vdev_t *cvd, vdev_ops_t *ops);
 320 extern void vdev_remove_parent(vdev_t *cvd);
 321
 322 /*
 323  * vdev sync load and sync
 324  */
 325 extern void vdev_load_log_state(vdev_t *nvd, vdev_t *ovd);
 326 extern boolean_t vdev_log_state_valid(vdev_t *vd);
 327 extern void vdev_load(vdev_t *vd);
 328 extern int vdev_dtl_load(vdev_t *vd);
 329 extern void vdev_sync(vdev_t *vd, uint64_t txg);
 330 extern void vdev_sync_done(vdev_t *vd, uint64_t txg);
 331 extern void vdev_dirty(vdev_t *vd, int flags, void *arg, uint64_t txg);
 332 extern void vdev_dirty_leaves(vdev_t *vd, int flags, uint64_t txg);
 333
 334 /*
 335  * Available vdev types.
 336  */
 337 extern vdev_ops_t vdev_root_ops;
 338 extern vdev_ops_t vdev_mirror_ops;
 339 extern vdev_ops_t vdev_replacing_ops;
 340 extern vdev_ops_t vdev_raidz_ops;
 341 extern vdev_ops_t vdev_disk_ops;
 342 extern vdev_ops_t vdev_file_ops;
 343 extern vdev_ops_t vdev_missing_ops;
 344 extern vdev_ops_t vdev_hole_ops;
 345 extern vdev_ops_t vdev_spare_ops;
 346
 347 /*
 348  * Common size functions
 349  */
 350 extern uint64_t vdev_default_asize(vdev_t *vd, uint64_t psize);
 351 extern uint64_t vdev_get_min_asize(vdev_t *vd);
 352 extern void vdev_set_min_asize(vdev_t *vd);
 353
 354 /*
 355  * Global variables
 356  */
 357 /* zdb uses this tunable, so it must be declared here to make lint happy. */
 358 extern int zfs_vdev_cache_size;
 359
 360 /*
 361  * The vdev_buf_t is used to translate between zio_t and buf_t, and back again.
 362  */
 363 typedef struct vdev_buf {
 364         buf_t   vb_buf;         /* buffer that describes the io */
 365         zio_t   *vb_io;         /* pointer back to the original zio_t */
 366 } vdev_buf_t;
 367
 368 #ifdef  __cplusplus
 369 }
 370 #endif
 371
 372 #endif  /* _SYS_VDEV_IMPL_H */