LXR linux/include/scsi/osd

   1/*
   2 * Copyright (C) 2011
   3 * Boaz Harrosh <bharrosh@panasas.com>
   4 *
   5 * Public Declarations of the ORE API
   6 *
   7 * This file is part of the ORE (Object Raid Engine) library.
   8 *
   9 * ORE is free software; you can redistribute it and/or modify
  10 * it under the terms of the GNU General Public License version 2 as published
  11 * by the Free Software Foundation. (GPL v2)
  12 *
  13 * ORE is distributed in the hope that it will be useful,
  14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 * GNU General Public License for more details.
  17 *
  18 * You should have received a copy of the GNU General Public License
  19 * along with the ORE; if not, write to the Free Software
  20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  21 */
  22#ifndef __ORE_H__
  23#define __ORE_H__
  24
  25#include <scsi/osd_initiator.h>
  26#include <scsi/osd_attributes.h>
  27#include <scsi/osd_sec.h>
  28#include <linux/pnfs_osd_xdr.h>
  29#include <linux/bug.h>
  30
  31struct ore_comp {
  32        struct osd_obj_id       obj;
  33        u8                      cred[OSD_CAP_LEN];
  34};
  35
  36struct ore_layout {
  37        /* Our way of looking at the data_map */
  38        enum pnfs_osd_raid_algorithm4
  39                 raid_algorithm;
  40        unsigned stripe_unit;
  41        unsigned mirrors_p1;
  42
  43        unsigned group_width;
  44        unsigned parity;
  45        u64      group_depth;
  46        unsigned group_count;
  47
  48        /* Cached often needed calculations filled in by
  49         * ore_verify_layout
  50         */
  51        unsigned long max_io_length;    /* Max length that should be passed to
  52                                         * ore_get_rw_state
  53                                         */
  54};
  55
  56struct ore_dev {
  57        struct osd_dev *od;
  58};
  59
  60struct ore_components {
  61        unsigned        first_dev;              /* First logical device no    */
  62        unsigned        numdevs;                /* Num of devices in array    */
  63        /* If @single_comp == EC_SINGLE_COMP, @comps points to a single
  64         * component. else there are @numdevs components
  65         */
  66        enum EC_COMP_USAGE {
  67                EC_SINGLE_COMP = 0, EC_MULTPLE_COMPS = 0xffffffff
  68        }               single_comp;
  69        struct ore_comp *comps;
  70
  71        /* Array of pointers to ore_dev-* . User will usually have these pointed
  72         * too a bigger struct which contain an "ore_dev ored" member and use
  73         * container_of(oc->ods[i], struct foo_dev, ored) to access the bigger
  74         * structure.
  75         */
  76        struct ore_dev  **ods;
  77};
  78
  79/* ore_comp_dev Recievies a logical device index */
  80static inline struct osd_dev *ore_comp_dev(
  81        const struct ore_components *oc, unsigned i)
  82{
  83        BUG_ON((i < oc->first_dev) || (oc->first_dev + oc->numdevs <= i));
  84        return oc->ods[i - oc->first_dev]->od;
  85}
  86
  87static inline void ore_comp_set_dev(
  88        struct ore_components *oc, unsigned i, struct osd_dev *od)
  89{
  90        oc->ods[i - oc->first_dev]->od = od;
  91}
  92
  93struct ore_striping_info {
  94        u64 offset;
  95        u64 obj_offset;
  96        u64 length;
  97        u64 first_stripe_start; /* only used in raid writes */
  98        u64 M; /* for truncate */
  99        unsigned bytes_in_stripe;
 100        unsigned dev;
 101        unsigned par_dev;
 102        unsigned unit_off;
 103        unsigned cur_pg;
 104        unsigned cur_comp;
 105};
 106
 107struct ore_io_state;
 108typedef void (*ore_io_done_fn)(struct ore_io_state *ios, void *private);
 109struct _ore_r4w_op {
 110        /* @Priv given here is passed ios->private */
 111        struct page * (*get_page)(void *priv, u64 page_index, bool *uptodate);
 112        void (*put_page)(void *priv, struct page *page);
 113};
 114
 115struct ore_io_state {
 116        struct kref             kref;
 117        struct ore_striping_info si;
 118
 119        void                    *private;
 120        ore_io_done_fn  done;
 121
 122        struct ore_layout       *layout;
 123        struct ore_components   *oc;
 124
 125        /* Global read/write IO*/
 126        loff_t                  offset;
 127        unsigned long           length;
 128        void                    *kern_buff;
 129
 130        struct page             **pages;
 131        unsigned                nr_pages;
 132        unsigned                pgbase;
 133        unsigned                pages_consumed;
 134
 135        /* Attributes */
 136        unsigned                in_attr_len;
 137        struct osd_attr         *in_attr;
 138        unsigned                out_attr_len;
 139        struct osd_attr         *out_attr;
 140
 141        bool                    reading;
 142
 143        /* House keeping of Parity pages */
 144        bool                    extra_part_alloc;
 145        struct page             **parity_pages;
 146        unsigned                max_par_pages;
 147        unsigned                cur_par_page;
 148        unsigned                sgs_per_dev;
 149        struct __stripe_pages_2d *sp2d;
 150        struct ore_io_state      *ios_read_4_write;
 151        const struct _ore_r4w_op *r4w;
 152
 153        /* Variable array of size numdevs */
 154        unsigned numdevs;
 155        struct ore_per_dev_state {
 156                struct osd_request *or;
 157                struct bio *bio;
 158                loff_t offset;
 159                unsigned length;
 160                unsigned last_sgs_total;
 161                unsigned dev;
 162                struct osd_sg_entry *sglist;
 163                unsigned cur_sg;
 164        } per_dev[];
 165};
 166
 167static inline unsigned ore_io_state_size(unsigned numdevs)
 168{
 169        return sizeof(struct ore_io_state) +
 170                sizeof(struct ore_per_dev_state) * numdevs;
 171}
 172
 173/* ore.c */
 174int ore_verify_layout(unsigned total_comps, struct ore_layout *layout);
 175void ore_calc_stripe_info(struct ore_layout *layout, u64 file_offset,
 176                          u64 length, struct ore_striping_info *si);
 177int ore_get_rw_state(struct ore_layout *layout, struct ore_components *comps,
 178                     bool is_reading, u64 offset, u64 length,
 179                     struct ore_io_state **ios);
 180int ore_get_io_state(struct ore_layout *layout, struct ore_components *comps,
 181                     struct ore_io_state **ios);
 182void ore_put_io_state(struct ore_io_state *ios);
 183
 184typedef void (*ore_on_dev_error)(struct ore_io_state *ios, struct ore_dev *od,
 185        unsigned dev_index, enum osd_err_priority oep,
 186        u64 dev_offset, u64  dev_len);
 187int ore_check_io(struct ore_io_state *ios, ore_on_dev_error rep);
 188
 189int ore_create(struct ore_io_state *ios);
 190int ore_remove(struct ore_io_state *ios);
 191int ore_write(struct ore_io_state *ios);
 192int ore_read(struct ore_io_state *ios);
 193int ore_truncate(struct ore_layout *layout, struct ore_components *comps,
 194                 u64 size);
 195
 196int extract_attr_from_ios(struct ore_io_state *ios, struct osd_attr *attr);
 197
 198extern const struct osd_attr g_attr_logical_length;
 199
 200#endif
 201