Merge branch 'for-linus' of git://git.open-osd.org/linux-open-osd into next

Pull exofs raid6 support from Boaz Harrosh:
 "These simple patches will enable raid6 using the kernel's raid6_pq
  engine for support under exofs and pnfs-objects.

  There is nothing needed to do at exofs and pnfs-obj.  Just fire your
  mkfs.exofs with --raid=6 (that was already supported before) and off
  you go as usual.  The ORE will pick up the new map and will start
  writing two devices of redundancy bits.  The patches are so simple
  because most of the ORE was already for the general raid case, only a
  few bug fixes were needed and the actual wiring into the raid6_pq
  engine"

* 'for-linus' of git://git.open-osd.org/linux-open-osd:
  ore: Support for raid 6
  ore: Remove redundant dev_order(), more cleanups
  ore: (trivial) reformat some code

1 files changed, 30 insertions, 26 deletions

diff --git a/fs/exofs/ore_raid.c b/fs/exofs/ore_raid.c
index 4e2c032ab8a1..7f20f25c232c 100644
--- a/fs/exofs/ore_raid.c
+++ b/fs/exofs/ore_raid.c
@@ -218,22 +218,28 @@ static unsigned _sp2d_max_pg(struct __stripe_pages_2d *sp2d)
 static void _gen_xor_unit(struct __stripe_pages_2d *sp2d)
 {
         unsigned p;
+        unsigned tx_flags = ASYNC_TX_ACK;
+
+        if (sp2d->parity == 1)
+                tx_flags |= ASYNC_TX_XOR_ZERO_DST;
+
         for (p = 0; p < sp2d->pages_in_unit; p++) {
                 struct __1_page_stripe *_1ps = &sp2d->_1p_stripes[p];
 
                 if (!_1ps->write_count)
                         continue;
 
-                init_async_submit(&_1ps->submit,
-                        ASYNC_TX_XOR_ZERO_DST | ASYNC_TX_ACK,
-                        NULL,
-                        NULL, NULL,
-                        (addr_conv_t *)_1ps->scribble);
-
-                /* TODO: raid6 */
-                _1ps->tx = async_xor(_1ps->pages[sp2d->data_devs], _1ps->pages,
-                                     0, sp2d->data_devs, PAGE_SIZE,
-                                     &_1ps->submit);
+                init_async_submit(&_1ps->submit, tx_flags,
+                        NULL, NULL, NULL, (addr_conv_t *)_1ps->scribble);
+
+                if (sp2d->parity == 1)
+                        _1ps->tx = async_xor(_1ps->pages[sp2d->data_devs],
+                                                _1ps->pages, 0, sp2d->data_devs,
+                                                PAGE_SIZE, &_1ps->submit);
+                else /* parity == 2 */
+                        _1ps->tx = async_gen_syndrome(_1ps->pages, 0,
+                                                sp2d->data_devs + sp2d->parity,
+                                                PAGE_SIZE, &_1ps->submit);
         }
 
         for (p = 0; p < sp2d->pages_in_unit; p++) {
@@ -404,9 +410,8 @@ static int _add_to_r4w_last_page(struct ore_io_state *ios, u64 *offset)
 
         ore_calc_stripe_info(ios->layout, *offset, 0, &si);
 
-        p = si.unit_off / PAGE_SIZE;
-        c = _dev_order(ios->layout->group_width * ios->layout->mirrors_p1,
-                       ios->layout->mirrors_p1, si.par_dev, si.dev);
+        p = si.cur_pg;
+        c = si.cur_comp;
         page = ios->sp2d->_1p_stripes[p].pages[c];
 
         pg_len = PAGE_SIZE - (si.unit_off % PAGE_SIZE);
@@ -534,9 +539,8 @@ static int _read_4_write_last_stripe(struct ore_io_state *ios)
                 goto read_it;
 
         ore_calc_stripe_info(ios->layout, offset, 0, &read_si);
-        p = read_si.unit_off / PAGE_SIZE;
-        c = _dev_order(ios->layout->group_width * ios->layout->mirrors_p1,
-                       ios->layout->mirrors_p1, read_si.par_dev, read_si.dev);
+        p = read_si.cur_pg;
+        c = read_si.cur_comp;
 
         if (min_p == sp2d->pages_in_unit) {
                 /* Didn't do it yet */
@@ -620,7 +624,7 @@ static int _read_4_write_execute(struct ore_io_state *ios)
 int _ore_add_parity_unit(struct ore_io_state *ios,
                             struct ore_striping_info *si,
                             struct ore_per_dev_state *per_dev,
-                            unsigned cur_len)
+                            unsigned cur_len, bool do_xor)
 {
         if (ios->reading) {
                 if (per_dev->cur_sg >= ios->sgs_per_dev) {
@@ -640,17 +644,16 @@ int _ore_add_parity_unit(struct ore_io_state *ios,
                 si->cur_pg = _sp2d_min_pg(sp2d);
                 num_pages  = _sp2d_max_pg(sp2d) + 1 - si->cur_pg;
 
-                if (!cur_len) /* If last stripe operate on parity comp */
-                        si->cur_comp = sp2d->data_devs;
-
                 if (!per_dev->length) {
                         per_dev->offset += si->cur_pg * PAGE_SIZE;
                         /* If first stripe, Read in all read4write pages
                          * (if needed) before we calculate the first parity.
                          */
-                        _read_4_write_first_stripe(ios);
+                        if (do_xor)
+                                _read_4_write_first_stripe(ios);
                 }
-                if (!cur_len) /* If last stripe r4w pages of last stripe */
+                if (!cur_len && do_xor)
+                        /* If last stripe r4w pages of last stripe */
                         _read_4_write_last_stripe(ios);
                 _read_4_write_execute(ios);
 
@@ -662,7 +665,7 @@ int _ore_add_parity_unit(struct ore_io_state *ios,
                         ++(ios->cur_par_page);
                 }
 
-                BUG_ON(si->cur_comp != sp2d->data_devs);
+                BUG_ON(si->cur_comp < sp2d->data_devs);
                 BUG_ON(si->cur_pg + num_pages > sp2d->pages_in_unit);
 
                 ret = _ore_add_stripe_unit(ios,  &array_start, 0, pages,
@@ -670,9 +673,10 @@ int _ore_add_parity_unit(struct ore_io_state *ios,
                 if (unlikely(ret))
                         return ret;
 
-                /* TODO: raid6 if (last_parity_dev) */
-                _gen_xor_unit(sp2d);
-                _sp2d_reset(sp2d, ios->r4w, ios->private);
+                if (do_xor) {
+                        _gen_xor_unit(sp2d);
+                        _sp2d_reset(sp2d, ios->r4w, ios->private);
+                }
         }
         return 0;
 }