FreeBSD/Linux Kernel Cross Reference
sys/contrib/openzfs/include/sys/sa_impl.h

     /*
      * CDDL HEADER START
      *
      * The contents of this file are subject to the terms of the
      * Common Development and Distribution License (the "License").
      * You may not use this file except in compliance with the License.
      *
      * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
      * or https://opensource.org/licenses/CDDL-1.0.
     * See the License for the specific language governing permissions
     * and limitations under the License.
     *
     * When distributing Covered Code, include this CDDL HEADER in each
     * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
     * If applicable, add the following below this CDDL HEADER, with the
     * fields enclosed by brackets "[]" replaced with your own identifying
     * information: Portions Copyright [yyyy] [name of copyright owner]
     *
     * CDDL HEADER END
     */
    /*
     * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
     * Copyright (c) 2013 by Delphix. All rights reserved.
     * Copyright (c) 2014 Spectra Logic Corporation, All rights reserved.
     */
    
    #ifndef _SYS_SA_IMPL_H
    #define _SYS_SA_IMPL_H
    
    #include <sys/dmu.h>
    #include <sys/zfs_refcount.h>
    #include <sys/list.h>
    
    /*
     * Array of known attributes and their
     * various characteristics.
     */
    typedef struct sa_attr_table {
            sa_attr_type_t  sa_attr;
            uint8_t sa_registered;
            uint16_t sa_length;
            sa_bswap_type_t sa_byteswap;
            char *sa_name;
    } sa_attr_table_t;
    
    /*
     * Zap attribute format for attribute registration
     *
     * 64      56      48      40      32      24      16      8       0
     * +-------+-------+-------+-------+-------+-------+-------+-------+
     * |        unused         |      len      | bswap |   attr num    |
     * +-------+-------+-------+-------+-------+-------+-------+-------+
     *
     * Zap attribute format for layout information.
     *
     * layout information is stored as an array of attribute numbers
     * The name of the attribute is the layout number (0, 1, 2, ...)
     *
     * 16       0
     * +---- ---+
     * | attr # |
     * +--------+
     * | attr # |
     * +--- ----+
     *  ......
     *
     */
    
    #define ATTR_BSWAP(x)   BF32_GET(x, 16, 8)
    #define ATTR_LENGTH(x)  BF32_GET(x, 24, 16)
    #define ATTR_NUM(x)     BF32_GET(x, 0, 16)
    #define ATTR_ENCODE(x, attr, length, bswap) \
    { \
            BF64_SET(x, 24, 16, length); \
            BF64_SET(x, 16, 8, bswap); \
            BF64_SET(x, 0, 16, attr); \
    }
    
    #define TOC_OFF(x)              BF32_GET(x, 0, 23)
    #define TOC_ATTR_PRESENT(x)     BF32_GET(x, 31, 1)
    #define TOC_LEN_IDX(x)          BF32_GET(x, 24, 4)
    #define TOC_ATTR_ENCODE(x, len_idx, offset) \
    { \
            BF32_SET(x, 31, 1, 1); \
            BF32_SET(x, 24, 7, len_idx); \
            BF32_SET(x, 0, 24, offset); \
    }
    
    #define SA_LAYOUTS      "LAYOUTS"
    #define SA_REGISTRY     "REGISTRY"
    
    /*
     * Each unique layout will have their own table
     * sa_lot (layout_table)
     */
    typedef struct sa_lot {
            avl_node_t lot_num_node;
            avl_node_t lot_hash_node;
            uint64_t lot_num;
           uint64_t lot_hash;
           sa_attr_type_t *lot_attrs;      /* array of attr #'s */
           uint32_t lot_var_sizes; /* how many aren't fixed size */
           uint32_t lot_attr_count;        /* total attr count */
           list_t  lot_idx_tab;    /* should be only a couple of entries */
           int     lot_instance;   /* used with lot_hash to identify entry */
   } sa_lot_t;
   
   /* index table of offsets */
   typedef struct sa_idx_tab {
           list_node_t     sa_next;
           sa_lot_t        *sa_layout;
           uint16_t        *sa_variable_lengths;
           zfs_refcount_t  sa_refcount;
           uint32_t        *sa_idx_tab;    /* array of offsets */
   } sa_idx_tab_t;
   
   /*
    * Since the offset/index information into the actual data
    * will usually be identical we can share that information with
    * all handles that have the exact same offsets.
    *
    * You would typically only have a large number of different table of
    * contents if you had a several variable sized attributes.
    *
    * Two AVL trees are used to track the attribute layout numbers.
    * one is keyed by number and will be consulted when a DMU_OT_SA
    * object is first read.  The second tree is keyed by the hash signature
    * of the attributes and will be consulted when an attribute is added
    * to determine if we already have an instance of that layout.  Both
    * of these tree's are interconnected.  The only difference is that
    * when an entry is found in the "hash" tree the list of attributes will
    * need to be compared against the list of attributes you have in hand.
    * The assumption is that typically attributes will just be updated and
    * adding a completely new attribute is a very rare operation.
    */
   struct sa_os {
           kmutex_t        sa_lock;
           boolean_t       sa_need_attr_registration;
           boolean_t       sa_force_spill;
           uint64_t        sa_master_obj;
           uint64_t        sa_reg_attr_obj;
           uint64_t        sa_layout_attr_obj;
           int             sa_num_attrs;
           sa_attr_table_t *sa_attr_table;  /* private attr table */
           sa_update_cb_t  *sa_update_cb;
           avl_tree_t      sa_layout_num_tree;  /* keyed by layout number */
           avl_tree_t      sa_layout_hash_tree; /* keyed by layout hash value */
           int             sa_user_table_sz;
           sa_attr_type_t  *sa_user_table; /* user name->attr mapping table */
   };
   
   /*
    * header for all bonus and spill buffers.
    *
    * The header has a fixed portion with a variable number
    * of "lengths" depending on the number of variable sized
    * attributes which are determined by the "layout number"
    */
   
   #define SA_MAGIC        0x2F505A  /* ZFS SA */
   typedef struct sa_hdr_phys {
           uint32_t sa_magic;
           /*
            * Encoded with hdrsize and layout number as follows:
            * 16      10       0
            * +--------+-------+
            * | hdrsz  |layout |
            * +--------+-------+
            *
            * Bits 0-10 are the layout number
            * Bits 11-16 are the size of the header.
            * The hdrsize is the number * 8
            *
            * For example.
            * hdrsz of 1 ==> 8 byte header
            *          2 ==> 16 byte header
            *
            */
           uint16_t sa_layout_info;
           uint16_t sa_lengths[1]; /* optional sizes for variable length attrs */
           /* ... Data follows the lengths.  */
   } sa_hdr_phys_t;
   
   #define SA_HDR_LAYOUT_NUM(hdr) BF32_GET(hdr->sa_layout_info, 0, 10)
   #define SA_HDR_SIZE(hdr) BF32_GET_SB(hdr->sa_layout_info, 10, 6, 3, 0)
   #define SA_HDR_LAYOUT_INFO_ENCODE(x, num, size) \
   { \
           BF32_SET_SB(x, 10, 6, 3, 0, size); \
           BF32_SET(x, 0, 10, num); \
   }
   
   typedef enum sa_buf_type {
           SA_BONUS = 1,
           SA_SPILL = 2
   } sa_buf_type_t;
   
   typedef enum sa_data_op {
           SA_LOOKUP,
           SA_UPDATE,
           SA_ADD,
           SA_REPLACE,
           SA_REMOVE
   } sa_data_op_t;
   
   /*
    * Opaque handle used for most sa functions
    *
    * This needs to be kept as small as possible.
    */
   
   struct sa_handle {
           dmu_buf_user_t  sa_dbu;
           kmutex_t        sa_lock;
           dmu_buf_t       *sa_bonus;
           dmu_buf_t       *sa_spill;
           objset_t        *sa_os;
           void            *sa_userp;
           sa_idx_tab_t    *sa_bonus_tab;   /* idx of bonus */
           sa_idx_tab_t    *sa_spill_tab; /* only present if spill activated */
   };
   
   #define SA_GET_DB(hdl, type)    \
           (dmu_buf_impl_t *)((type == SA_BONUS) ? hdl->sa_bonus : hdl->sa_spill)
   
   #define SA_GET_HDR(hdl, type) \
           ((sa_hdr_phys_t *)((dmu_buf_impl_t *)(SA_GET_DB(hdl, \
           type))->db.db_data))
   
   #define SA_IDX_TAB_GET(hdl, type) \
           (type == SA_BONUS ? hdl->sa_bonus_tab : hdl->sa_spill_tab)
   
   #define IS_SA_BONUSTYPE(a)      \
           ((a == DMU_OT_SA) ? B_TRUE : B_FALSE)
   
   #define SA_BONUSTYPE_FROM_DB(db) \
           (dmu_get_bonustype((dmu_buf_t *)db))
   
   #define SA_BLKPTR_SPACE (DN_OLD_MAX_BONUSLEN - sizeof (blkptr_t))
   
   #define SA_LAYOUT_NUM(x, type) \
           ((!IS_SA_BONUSTYPE(type) ? 0 : (((IS_SA_BONUSTYPE(type)) && \
           ((SA_HDR_LAYOUT_NUM(x)) == 0)) ? 1 : SA_HDR_LAYOUT_NUM(x))))
   
   
   #define SA_REGISTERED_LEN(sa, attr) sa->sa_attr_table[attr].sa_length
   
   #define SA_ATTR_LEN(sa, idx, attr, hdr) ((SA_REGISTERED_LEN(sa, attr) == 0) ?\
           hdr->sa_lengths[TOC_LEN_IDX(idx->sa_idx_tab[attr])] : \
           SA_REGISTERED_LEN(sa, attr))
   
   #define SA_SET_HDR(hdr, num, size) \
           { \
                   hdr->sa_magic = SA_MAGIC; \
                   SA_HDR_LAYOUT_INFO_ENCODE(hdr->sa_layout_info, num, size); \
           }
   
   #define SA_ATTR_INFO(sa, idx, hdr, attr, bulk, type, hdl) \
           { \
                   bulk.sa_size = SA_ATTR_LEN(sa, idx, attr, hdr); \
                   bulk.sa_buftype = type; \
                   bulk.sa_addr = \
                       (void *)((uintptr_t)TOC_OFF(idx->sa_idx_tab[attr]) + \
                       (uintptr_t)hdr); \
   }
   
   #define SA_HDR_SIZE_MATCH_LAYOUT(hdr, tb) \
           (SA_HDR_SIZE(hdr) == (sizeof (sa_hdr_phys_t) + \
           (tb->lot_var_sizes > 1 ? P2ROUNDUP((tb->lot_var_sizes - 1) * \
           sizeof (uint16_t), 8) : 0)))
   
   int sa_add_impl(sa_handle_t *, sa_attr_type_t,
       uint32_t, sa_data_locator_t, void *, dmu_tx_t *);
   
   void sa_register_update_callback_locked(objset_t *, sa_update_cb_t *);
   int sa_size_locked(sa_handle_t *, sa_attr_type_t, int *);
   
   void sa_default_locator(void **, uint32_t *, uint32_t, boolean_t, void *);
   int sa_attr_size(sa_os_t *, sa_idx_tab_t *, sa_attr_type_t,
       uint16_t *, sa_hdr_phys_t *);
   
   #ifdef  __cplusplus
   extern "C" {
   #endif
   
   #ifdef  __cplusplus
   }
   #endif
   
   #endif  /* _SYS_SA_IMPL_H */

Cache object: 2e6e166c2f014e699ed4c7c0c6154043