include/scsi/osd_ore.h

   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
  31 struct ore_comp {
  32         struct osd_obj_id       obj;
  33         u8                      cred[OSD_CAP_LEN];
  34 };
  35
  36 struct 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
  56 struct ore_dev {
  57         struct osd_dev *od;
  58 };
  59
  60 struct 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 */
  80 static 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
  87 static 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
  93 struct 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
 107 struct ore_io_state;
 108 typedef void (*ore_io_done_fn)(struct ore_io_state *ios, void *private);
 109 struct _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
 115 struct 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
 167 static 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 */
 174 int ore_verify_layout(unsigned total_comps, struct ore_layout *layout);
 175 void ore_calc_stripe_info(struct ore_layout *layout, u64 file_offset,
 176                           u64 length, struct ore_striping_info *si);
 177 int 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);
 180 int ore_get_io_state(struct ore_layout *layout, struct ore_components *comps,
 181                      struct ore_io_state **ios);
 182 void ore_put_io_state(struct ore_io_state *ios);
 183
 184 typedef 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);
 187 int ore_check_io(struct ore_io_state *ios, ore_on_dev_error rep);
 188
 189 int ore_create(struct ore_io_state *ios);
 190 int ore_remove(struct ore_io_state *ios);
 191 int ore_write(struct ore_io_state *ios);
 192 int ore_read(struct ore_io_state *ios);
 193 int ore_truncate(struct ore_layout *layout, struct ore_components *comps,
 194                  u64 size);
 195
 196 int extract_attr_from_ios(struct ore_io_state *ios, struct osd_attr *attr);
 197
 198 extern const struct osd_attr g_attr_logical_length;
 199
 200 #endif