usr/src/uts/common/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) 2012 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 /*
  57  * Virtual device operations
  58  */
  59 typedef int     vdev_open_func_t(vdev_t *vd, uint64_t *size, uint64_t *max_size,
  60     uint64_t *ashift);
  61 typedef void    vdev_close_func_t(vdev_t *vd);
  62 typedef uint64_t vdev_asize_func_t(vdev_t *vd, uint64_t psize);
  63 typedef int     vdev_io_start_func_t(zio_t *zio);
  64 typedef void    vdev_io_done_func_t(zio_t *zio);
  65 typedef void    vdev_state_change_func_t(vdev_t *vd, int, int);
  66 typedef void    vdev_hold_func_t(vdev_t *vd);
  67 typedef void    vdev_rele_func_t(vdev_t *vd);
  68
  69 typedef struct vdev_ops {
  70         vdev_open_func_t                *vdev_op_open;
  71         vdev_close_func_t               *vdev_op_close;
  72         vdev_asize_func_t               *vdev_op_asize;
  73         vdev_io_start_func_t            *vdev_op_io_start;
  74         vdev_io_done_func_t             *vdev_op_io_done;
  75         vdev_state_change_func_t        *vdev_op_state_change;
  76         vdev_hold_func_t                *vdev_op_hold;
  77         vdev_rele_func_t                *vdev_op_rele;
  78         char                            vdev_op_type[16];
  79         boolean_t                       vdev_op_leaf;
  80 } vdev_ops_t;
  81
  82 /*
  83  * Virtual device properties
  84  */
  85 struct vdev_cache_entry {
  86         char            *ve_data;
  87         uint64_t        ve_offset;
  88         uint64_t        ve_lastused;
  89         avl_node_t      ve_offset_node;
  90         avl_node_t      ve_lastused_node;
  91         uint32_t        ve_hits;
  92         uint16_t        ve_missed_update;
  93         zio_t           *ve_fill_io;
  94 };
  95
  96 struct vdev_cache {
  97         avl_tree_t      vc_offset_tree;
  98         avl_tree_t      vc_lastused_tree;
  99         kmutex_t        vc_lock;
 100 };
 101
 102 struct vdev_queue {
 103         avl_tree_t      vq_deadline_tree;
 104         avl_tree_t      vq_read_tree;
 105         avl_tree_t      vq_write_tree;
 106         avl_tree_t      vq_pending_tree;
 107         uint64_t        vq_io_complete_ts;
 108         uint64_t        vq_io_delta_ts;
 109         kmutex_t        vq_lock;
 110 };
 111
 112 /*
 113  * Virtual device descriptor
 114  */
 115 struct vdev {
 116         /*
 117          * Common to all vdev types.
 118          */
 119         uint64_t        vdev_id;        /* child number in vdev parent  */
 120         uint64_t        vdev_guid;      /* unique ID for this vdev      */
 121         uint64_t        vdev_guid_sum;  /* self guid + all child guids  */
 122         uint64_t        vdev_orig_guid; /* orig. guid prior to remove   */
 123         uint64_t        vdev_asize;     /* allocatable device capacity  */
 124         uint64_t        vdev_min_asize; /* min acceptable asize         */
 125         uint64_t        vdev_max_asize; /* max acceptable asize         */
 126         uint64_t        vdev_ashift;    /* block alignment shift        */
 127         uint64_t        vdev_state;     /* see VDEV_STATE_* #defines    */
 128         uint64_t        vdev_prevstate; /* used when reopening a vdev   */
 129         vdev_ops_t      *vdev_ops;      /* vdev operations              */
 130         spa_t           *vdev_spa;      /* spa for this vdev            */
 131         void            *vdev_tsd;      /* type-specific data           */
 132         vnode_t         *vdev_name_vp;  /* vnode for pathname           */
 133         vnode_t         *vdev_devid_vp; /* vnode for devid              */
 134         vdev_t          *vdev_top;      /* top-level vdev               */
 135         vdev_t          *vdev_parent;   /* parent vdev                  */
 136         vdev_t          **vdev_child;   /* array of children            */
 137         uint64_t        vdev_children;  /* number of children           */
 138         space_map_t     vdev_dtl[DTL_TYPES]; /* in-core dirty time logs */
 139         vdev_stat_t     vdev_stat;      /* virtual device statistics    */
 140         boolean_t       vdev_expanding; /* expand the vdev?             */
 141         boolean_t       vdev_reopening; /* reopen in progress?          */
 142         int             vdev_open_error; /* error on last open          */
 143         kthread_t       *vdev_open_thread; /* thread opening children   */
 144         uint64_t        vdev_crtxg;     /* txg when top-level was added */
 145
 146         /*
 147          * Top-level vdev state.
 148          */
 149         uint64_t        vdev_ms_array;  /* metaslab array object        */
 150         uint64_t        vdev_ms_shift;  /* metaslab size shift          */
 151         uint64_t        vdev_ms_count;  /* number of metaslabs          */
 152         metaslab_group_t *vdev_mg;      /* metaslab group               */
 153         metaslab_t      **vdev_ms;      /* metaslab array               */
 154         txg_list_t      vdev_ms_list;   /* per-txg dirty metaslab lists */
 155         txg_list_t      vdev_dtl_list;  /* per-txg dirty DTL lists      */
 156         txg_node_t      vdev_txg_node;  /* per-txg dirty vdev linkage   */
 157         boolean_t       vdev_remove_wanted; /* async remove wanted?     */
 158         boolean_t       vdev_probe_wanted; /* async probe wanted?       */
 159         uint64_t        vdev_removing;  /* device is being removed?     */
 160         list_node_t     vdev_config_dirty_node; /* config dirty list    */
 161         list_node_t     vdev_state_dirty_node; /* state dirty list      */
 162         uint64_t        vdev_deflate_ratio; /* deflation ratio (x512)   */
 163         uint64_t        vdev_islog;     /* is an intent log device      */
 164         uint64_t        vdev_ishole;    /* is a hole in the namespace   */
 165
 166         /*
 167          * Leaf vdev state.
 168          */
 169         uint64_t        vdev_psize;     /* physical device capacity     */
 170         space_map_obj_t vdev_dtl_smo;   /* dirty time log space map obj */
 171         txg_node_t      vdev_dtl_node;  /* per-txg dirty DTL linkage    */
 172         uint64_t        vdev_wholedisk; /* true if this is a whole disk */
 173         uint64_t        vdev_offline;   /* persistent offline state     */
 174         uint64_t        vdev_faulted;   /* persistent faulted state     */
 175         uint64_t        vdev_degraded;  /* persistent degraded state    */
 176         uint64_t        vdev_removed;   /* persistent removed state     */
 177         uint64_t        vdev_resilvering; /* persistent resilvering state */
 178         uint64_t        vdev_nparity;   /* number of parity devices for raidz */
 179         char            *vdev_path;     /* vdev path (if any)           */
 180         char            *vdev_devid;    /* vdev devid (if any)          */
 181         char            *vdev_physpath; /* vdev device path (if any)    */
 182         char            *vdev_fru;      /* physical FRU location        */
 183         uint64_t        vdev_not_present; /* not present during import  */
 184         uint64_t        vdev_unspare;   /* unspare when resilvering done */
 185         hrtime_t        vdev_last_try;  /* last reopen time             */
 186         boolean_t       vdev_nowritecache; /* true if flushwritecache failed */
 187         boolean_t       vdev_checkremove; /* temporary online test      */
 188         boolean_t       vdev_forcefault; /* force online fault          */
 189         boolean_t       vdev_splitting; /* split or repair in progress  */
 190         boolean_t       vdev_delayed_close; /* delayed device close?    */
 191         uint8_t         vdev_tmpoffline; /* device taken offline temporarily? */
 192         uint8_t         vdev_detached;  /* device detached?             */
 193         uint8_t         vdev_cant_read; /* vdev is failing all reads    */
 194         uint8_t         vdev_cant_write; /* vdev is failing all writes  */
 195         uint64_t        vdev_isspare;   /* was a hot spare              */
 196         uint64_t        vdev_isl2cache; /* was a l2cache device         */
 197         vdev_queue_t    vdev_queue;     /* I/O deadline schedule queue  */
 198         vdev_cache_t    vdev_cache;     /* physical block cache         */
 199         spa_aux_vdev_t  *vdev_aux;      /* for l2cache vdevs            */
 200         zio_t           *vdev_probe_zio; /* root of current probe       */
 201         vdev_aux_t      vdev_label_aux; /* on-disk aux state            */
 202
 203         /*
 204          * For DTrace to work in userland (libzpool) context, these fields must
 205          * remain at the end of the structure.  DTrace will use the kernel's
 206          * CTF definition for 'struct vdev', and since the size of a kmutex_t is
 207          * larger in userland, the offsets for the rest of the fields would be
 208          * incorrect.
 209          */
 210         kmutex_t        vdev_dtl_lock;  /* vdev_dtl_{map,resilver}      */
 211         kmutex_t        vdev_stat_lock; /* vdev_stat                    */
 212         kmutex_t        vdev_probe_lock; /* protects vdev_probe_zio     */
 213 };
 214
 215 #define VDEV_RAIDZ_MAXPARITY    3
 216
 217 #define VDEV_PAD_SIZE           (8 << 10)
 218 /* 2 padding areas (vl_pad1 and vl_pad2) to skip */
 219 #define VDEV_SKIP_SIZE          VDEV_PAD_SIZE * 2
 220 #define VDEV_PHYS_SIZE          (112 << 10)
 221 #define VDEV_UBERBLOCK_RING     (128 << 10)
 222
 223 #define VDEV_UBERBLOCK_SHIFT(vd)        \
 224         MAX((vd)->vdev_top->vdev_ashift, UBERBLOCK_SHIFT)
 225 #define VDEV_UBERBLOCK_COUNT(vd)        \
 226         (VDEV_UBERBLOCK_RING >> VDEV_UBERBLOCK_SHIFT(vd))
 227 #define VDEV_UBERBLOCK_OFFSET(vd, n)    \
 228         offsetof(vdev_label_t, vl_uberblock[(n) << VDEV_UBERBLOCK_SHIFT(vd)])
 229 #define VDEV_UBERBLOCK_SIZE(vd)         (1ULL << VDEV_UBERBLOCK_SHIFT(vd))
 230
 231 typedef struct vdev_phys {
 232         char            vp_nvlist[VDEV_PHYS_SIZE - sizeof (zio_eck_t)];
 233         zio_eck_t       vp_zbt;
 234 } vdev_phys_t;
 235
 236 typedef struct vdev_label {
 237         char            vl_pad1[VDEV_PAD_SIZE];                 /*  8K */
 238         char            vl_pad2[VDEV_PAD_SIZE];                 /*  8K */
 239         vdev_phys_t     vl_vdev_phys;                           /* 112K */
 240         char            vl_uberblock[VDEV_UBERBLOCK_RING];      /* 128K */
 241 } vdev_label_t;                                                 /* 256K total */
 242
 243 /*
 244  * vdev_dirty() flags
 245  */
 246 #define VDD_METASLAB    0x01
 247 #define VDD_DTL         0x02
 248
 249 /*
 250  * Size and offset of embedded boot loader region on each label.
 251  * The total size of the first two labels plus the boot area is 4MB.
 252  */
 253 #define VDEV_BOOT_OFFSET        (2 * sizeof (vdev_label_t))
 254 #define VDEV_BOOT_SIZE          (7ULL << 19)                    /* 3.5M */
 255
 256 /*
 257  * Size of label regions at the start and end of each leaf device.
 258  */
 259 #define VDEV_LABEL_START_SIZE   (2 * sizeof (vdev_label_t) + VDEV_BOOT_SIZE)
 260 #define VDEV_LABEL_END_SIZE     (2 * sizeof (vdev_label_t))
 261 #define VDEV_LABELS             4
 262 #define VDEV_BEST_LABEL         VDEV_LABELS
 263
 264 #define VDEV_ALLOC_LOAD         0
 265 #define VDEV_ALLOC_ADD          1
 266 #define VDEV_ALLOC_SPARE        2
 267 #define VDEV_ALLOC_L2CACHE      3
 268 #define VDEV_ALLOC_ROOTPOOL     4
 269 #define VDEV_ALLOC_SPLIT        5
 270 #define VDEV_ALLOC_ATTACH       6
 271
 272 /*
 273  * Allocate or free a vdev
 274  */
 275 extern vdev_t *vdev_alloc_common(spa_t *spa, uint_t id, uint64_t guid,
 276     vdev_ops_t *ops);
 277 extern int vdev_alloc(spa_t *spa, vdev_t **vdp, nvlist_t *config,
 278     vdev_t *parent, uint_t id, int alloctype);
 279 extern void vdev_free(vdev_t *vd);
 280
 281 /*
 282  * Add or remove children and parents
 283  */
 284 extern void vdev_add_child(vdev_t *pvd, vdev_t *cvd);
 285 extern void vdev_remove_child(vdev_t *pvd, vdev_t *cvd);
 286 extern void vdev_compact_children(vdev_t *pvd);
 287 extern vdev_t *vdev_add_parent(vdev_t *cvd, vdev_ops_t *ops);
 288 extern void vdev_remove_parent(vdev_t *cvd);
 289
 290 /*
 291  * vdev sync load and sync
 292  */
 293 extern void vdev_load_log_state(vdev_t *nvd, vdev_t *ovd);
 294 extern boolean_t vdev_log_state_valid(vdev_t *vd);
 295 extern void vdev_load(vdev_t *vd);
 296 extern void vdev_sync(vdev_t *vd, uint64_t txg);
 297 extern void vdev_sync_done(vdev_t *vd, uint64_t txg);
 298 extern void vdev_dirty(vdev_t *vd, int flags, void *arg, uint64_t txg);
 299
 300 /*
 301  * Available vdev types.
 302  */
 303 extern vdev_ops_t vdev_root_ops;
 304 extern vdev_ops_t vdev_mirror_ops;
 305 extern vdev_ops_t vdev_replacing_ops;
 306 extern vdev_ops_t vdev_raidz_ops;
 307 extern vdev_ops_t vdev_disk_ops;
 308 extern vdev_ops_t vdev_file_ops;
 309 extern vdev_ops_t vdev_missing_ops;
 310 extern vdev_ops_t vdev_hole_ops;
 311 extern vdev_ops_t vdev_spare_ops;
 312
 313 /*
 314  * Common size functions
 315  */
 316 extern uint64_t vdev_default_asize(vdev_t *vd, uint64_t psize);
 317 extern uint64_t vdev_get_min_asize(vdev_t *vd);
 318 extern void vdev_set_min_asize(vdev_t *vd);
 319
 320 /*
 321  * zdb uses this tunable, so it must be declared here to make lint happy.
 322  */
 323 extern int zfs_vdev_cache_size;
 324
 325 /*
 326  * The vdev_buf_t is used to translate between zio_t and buf_t, and back again.
 327  */
 328 typedef struct vdev_buf {
 329         buf_t   vb_buf;         /* buffer that describes the io */
 330         zio_t   *vb_io;         /* pointer back to the original zio_t */
 331 } vdev_buf_t;
 332
 333 #ifdef  __cplusplus
 334 }
 335 #endif
 336
 337 #endif  /* _SYS_VDEV_IMPL_H */