*/
#include <linux/gfp.h>
+#include <linux/async_tx.h>
#include "ore_raid.h"
+#undef ORE_DBGMSG2
+#define ORE_DBGMSG2 ORE_DBGMSG
+
struct page *_raid_page_alloc(void)
{
return alloc_page(GFP_KERNEL);
__free_page(p);
}
+/* This struct is forward declare in ore_io_state, but is private to here.
+ * It is put on ios->sp2d for RAID5/6 writes only. See _gen_xor_unit.
+ *
+ * __stripe_pages_2d is a 2d array of pages, and it is also a corner turn.
+ * Ascending page index access is sp2d(p-minor, c-major). But storage is
+ * sp2d[p-minor][c-major], so it can be properlly presented to the async-xor
+ * API.
+ */
+struct __stripe_pages_2d {
+ /* Cache some hot path repeated calculations */
+ unsigned parity;
+ unsigned data_devs;
+ unsigned pages_in_unit;
+
+ bool needed ;
+
+ /* Array size is pages_in_unit (layout->stripe_unit / PAGE_SIZE) */
+ struct __1_page_stripe {
+ bool alloc;
+ unsigned write_count;
+ struct async_submit_ctl submit;
+ struct dma_async_tx_descriptor *tx;
+
+ /* The size of this array is data_devs + parity */
+ struct page **pages;
+ struct page **scribble;
+ /* bool array, size of this array is data_devs */
+ char *page_is_read;
+ } _1p_stripes[];
+};
+
+/* This can get bigger then a page. So support multiple page allocations
+ * _sp2d_free should be called even if _sp2d_alloc fails (by returning
+ * none-zero).
+ */
+static int _sp2d_alloc(unsigned pages_in_unit, unsigned group_width,
+ unsigned parity, struct __stripe_pages_2d **psp2d)
+{
+ struct __stripe_pages_2d *sp2d;
+ unsigned data_devs = group_width - parity;
+ struct _alloc_all_bytes {
+ struct __alloc_stripe_pages_2d {
+ struct __stripe_pages_2d sp2d;
+ struct __1_page_stripe _1p_stripes[pages_in_unit];
+ } __asp2d;
+ struct __alloc_1p_arrays {
+ struct page *pages[group_width];
+ struct page *scribble[group_width];
+ char page_is_read[data_devs];
+ } __a1pa[pages_in_unit];
+ } *_aab;
+ struct __alloc_1p_arrays *__a1pa;
+ struct __alloc_1p_arrays *__a1pa_end;
+ const unsigned sizeof__a1pa = sizeof(_aab->__a1pa[0]);
+ unsigned num_a1pa, alloc_size, i;
+
+ /* FIXME: check these numbers in ore_verify_layout */
+ BUG_ON(sizeof(_aab->__asp2d) > PAGE_SIZE);
+ BUG_ON(sizeof__a1pa > PAGE_SIZE);
+
+ if (sizeof(*_aab) > PAGE_SIZE) {
+ num_a1pa = (PAGE_SIZE - sizeof(_aab->__asp2d)) / sizeof__a1pa;
+ alloc_size = sizeof(_aab->__asp2d) + sizeof__a1pa * num_a1pa;
+ } else {
+ num_a1pa = pages_in_unit;
+ alloc_size = sizeof(*_aab);
+ }
+
+ _aab = kzalloc(alloc_size, GFP_KERNEL);
+ if (unlikely(!_aab)) {
+ ORE_DBGMSG("!! Failed to alloc sp2d size=%d\n", alloc_size);
+ return -ENOMEM;
+ }
+
+ sp2d = &_aab->__asp2d.sp2d;
+ *psp2d = sp2d; /* From here Just call _sp2d_free */
+
+ __a1pa = _aab->__a1pa;
+ __a1pa_end = __a1pa + num_a1pa;
+
+ for (i = 0; i < pages_in_unit; ++i) {
+ if (unlikely(__a1pa >= __a1pa_end)) {
+ num_a1pa = min_t(unsigned, PAGE_SIZE / sizeof__a1pa,
+ pages_in_unit - i);
+
+ __a1pa = kzalloc(num_a1pa * sizeof__a1pa, GFP_KERNEL);
+ if (unlikely(!__a1pa)) {
+ ORE_DBGMSG("!! Failed to _alloc_1p_arrays=%d\n",
+ num_a1pa);
+ return -ENOMEM;
+ }
+ __a1pa_end = __a1pa + num_a1pa;
+ /* First *pages is marked for kfree of the buffer */
+ sp2d->_1p_stripes[i].alloc = true;
+ }
+
+ sp2d->_1p_stripes[i].pages = __a1pa->pages;
+ sp2d->_1p_stripes[i].scribble = __a1pa->scribble ;
+ sp2d->_1p_stripes[i].page_is_read = __a1pa->page_is_read;
+ ++__a1pa;
+ }
+
+ sp2d->parity = parity;
+ sp2d->data_devs = data_devs;
+ sp2d->pages_in_unit = pages_in_unit;
+ return 0;
+}
+
+static void _sp2d_reset(struct __stripe_pages_2d *sp2d,
+ const struct _ore_r4w_op *r4w, void *priv)
+{
+ unsigned data_devs = sp2d->data_devs;
+ unsigned group_width = data_devs + sp2d->parity;
+ unsigned p;
+
+ if (!sp2d->needed)
+ return;
+
+ for (p = 0; p < sp2d->pages_in_unit; p++) {
+ struct __1_page_stripe *_1ps = &sp2d->_1p_stripes[p];
+
+ if (_1ps->write_count < group_width) {
+ unsigned c;
+
+ for (c = 0; c < data_devs; c++)
+ if (_1ps->page_is_read[c]) {
+ struct page *page = _1ps->pages[c];
+
+ r4w->put_page(priv, page);
+ _1ps->page_is_read[c] = false;
+ }
+ }
+
+ memset(_1ps->pages, 0, group_width * sizeof(*_1ps->pages));
+ _1ps->write_count = 0;
+ _1ps->tx = NULL;
+ }
+
+ sp2d->needed = false;
+}
+
+static void _sp2d_free(struct __stripe_pages_2d *sp2d)
+{
+ unsigned i;
+
+ if (!sp2d)
+ return;
+
+ for (i = 0; i < sp2d->pages_in_unit; ++i) {
+ if (sp2d->_1p_stripes[i].alloc)
+ kfree(sp2d->_1p_stripes[i].pages);
+ }
+
+ kfree(sp2d);
+}
+
+static unsigned _sp2d_min_pg(struct __stripe_pages_2d *sp2d)
+{
+ unsigned p;
+
+ for (p = 0; p < sp2d->pages_in_unit; p++) {
+ struct __1_page_stripe *_1ps = &sp2d->_1p_stripes[p];
+
+ if (_1ps->write_count)
+ return p;
+ }
+
+ return ~0;
+}
+
+static unsigned _sp2d_max_pg(struct __stripe_pages_2d *sp2d)
+{
+ unsigned p;
+
+ for (p = sp2d->pages_in_unit - 1; p >= 0; --p) {
+ struct __1_page_stripe *_1ps = &sp2d->_1p_stripes[p];
+
+ if (_1ps->write_count)
+ return p;
+ }
+
+ return ~0;
+}
+
+static void _gen_xor_unit(struct __stripe_pages_2d *sp2d)
+{
+ unsigned p;
+ 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);
+ }
+
+ for (p = 0; p < sp2d->pages_in_unit; p++) {
+ struct __1_page_stripe *_1ps = &sp2d->_1p_stripes[p];
+ /* NOTE: We wait for HW synchronously (I don't have such HW
+ * to test with.) Is parallelism needed with today's multi
+ * cores?
+ */
+ async_tx_issue_pending(_1ps->tx);
+ }
+}
+
+void _ore_add_stripe_page(struct __stripe_pages_2d *sp2d,
+ struct ore_striping_info *si, struct page *page)
+{
+ struct __1_page_stripe *_1ps;
+
+ sp2d->needed = true;
+
+ _1ps = &sp2d->_1p_stripes[si->cur_pg];
+ _1ps->pages[si->cur_comp] = page;
+ ++_1ps->write_count;
+
+ si->cur_pg = (si->cur_pg + 1) % sp2d->pages_in_unit;
+ /* si->cur_comp is advanced outside at main loop */
+}
+
void _ore_add_sg_seg(struct ore_per_dev_state *per_dev, unsigned cur_len,
bool not_last)
{
}
}
+static int _alloc_read_4_write(struct ore_io_state *ios)
+{
+ struct ore_layout *layout = ios->layout;
+ int ret;
+ /* We want to only read those pages not in cache so worst case
+ * is a stripe populated with every other page
+ */
+ unsigned sgs_per_dev = ios->sp2d->pages_in_unit + 2;
+
+ ret = _ore_get_io_state(layout, ios->oc,
+ layout->group_width * layout->mirrors_p1,
+ sgs_per_dev, 0, &ios->ios_read_4_write);
+ return ret;
+}
+
+/* @si contains info of the to-be-inserted page. Update of @si should be
+ * maintained by caller. Specificaly si->dev, si->obj_offset, ...
+ */
+static int _add_to_read_4_write(struct ore_io_state *ios,
+ struct ore_striping_info *si, struct page *page)
+{
+ struct request_queue *q;
+ struct ore_per_dev_state *per_dev;
+ struct ore_io_state *read_ios;
+ unsigned first_dev = si->dev - (si->dev %
+ (ios->layout->group_width * ios->layout->mirrors_p1));
+ unsigned comp = si->dev - first_dev;
+ unsigned added_len;
+
+ if (!ios->ios_read_4_write) {
+ int ret = _alloc_read_4_write(ios);
+
+ if (unlikely(ret))
+ return ret;
+ }
+
+ read_ios = ios->ios_read_4_write;
+ read_ios->numdevs = ios->layout->group_width * ios->layout->mirrors_p1;
+
+ per_dev = &read_ios->per_dev[comp];
+ if (!per_dev->length) {
+ per_dev->bio = bio_kmalloc(GFP_KERNEL,
+ ios->sp2d->pages_in_unit);
+ if (unlikely(!per_dev->bio)) {
+ ORE_DBGMSG("Failed to allocate BIO size=%u\n",
+ ios->sp2d->pages_in_unit);
+ return -ENOMEM;
+ }
+ per_dev->offset = si->obj_offset;
+ per_dev->dev = si->dev;
+ } else if (si->obj_offset != (per_dev->offset + per_dev->length)) {
+ u64 gap = si->obj_offset - (per_dev->offset + per_dev->length);
+
+ _ore_add_sg_seg(per_dev, gap, true);
+ }
+ q = osd_request_queue(ore_comp_dev(read_ios->oc, per_dev->dev));
+ added_len = bio_add_pc_page(q, per_dev->bio, page, PAGE_SIZE, 0);
+ if (unlikely(added_len != PAGE_SIZE)) {
+ ORE_DBGMSG("Failed to bio_add_pc_page bi_vcnt=%d\n",
+ per_dev->bio->bi_vcnt);
+ return -ENOMEM;
+ }
+
+ per_dev->length += PAGE_SIZE;
+ return 0;
+}
+
+static void _mark_read4write_pages_uptodate(struct ore_io_state *ios, int ret)
+{
+ struct bio_vec *bv;
+ unsigned i, d;
+
+ /* loop on all devices all pages */
+ for (d = 0; d < ios->numdevs; d++) {
+ struct bio *bio = ios->per_dev[d].bio;
+
+ if (!bio)
+ continue;
+
+ __bio_for_each_segment(bv, bio, i, 0) {
+ struct page *page = bv->bv_page;
+
+ SetPageUptodate(page);
+ if (PageError(page))
+ ClearPageError(page);
+ }
+ }
+}
+
+/* read_4_write is hacked to read the start of the first stripe and/or
+ * the end of the last stripe. If needed, with an sg-gap at each device/page.
+ * It is assumed to be called after the to_be_written pages of the first stripe
+ * are populating ios->sp2d[][]
+ *
+ * NOTE: We call ios->r4w->lock_fn for all pages needed for parity calculations
+ * These pages are held at sp2d[p].pages[c] but with
+ * sp2d[p].page_is_read[c] = true. At _sp2d_reset these pages are
+ * ios->r4w->lock_fn(). The ios->r4w->lock_fn might signal that the page is
+ * @uptodate=true, so we don't need to read it, only unlock, after IO.
+ *
+ * TODO: The read_4_write should calc a need_to_read_pages_count, if bigger then
+ * to-be-written count, we should consider the xor-in-place mode.
+ * need_to_read_pages_count is the actual number of pages not present in cache.
+ * maybe "devs_in_group - ios->sp2d[p].write_count" is a good enough
+ * approximation? In this mode the read pages are put in the empty places of
+ * ios->sp2d[p][*], xor is calculated the same way. These pages are
+ * allocated/freed and don't go through cache
+ */
+static int _read_4_write(struct ore_io_state *ios)
+{
+ struct ore_io_state *ios_read;
+ struct ore_striping_info read_si;
+ struct __stripe_pages_2d *sp2d = ios->sp2d;
+ u64 offset = ios->si.first_stripe_start;
+ u64 last_stripe_end;
+ unsigned bytes_in_stripe = ios->si.bytes_in_stripe;
+ unsigned i, c, p, min_p = sp2d->pages_in_unit, max_p = -1;
+ int ret;
+
+ if (offset == ios->offset) /* Go to start collect $200 */
+ goto read_last_stripe;
+
+ min_p = _sp2d_min_pg(sp2d);
+ max_p = _sp2d_max_pg(sp2d);
+
+ for (c = 0; ; c++) {
+ ore_calc_stripe_info(ios->layout, offset, 0, &read_si);
+ read_si.obj_offset += min_p * PAGE_SIZE;
+ offset += min_p * PAGE_SIZE;
+ for (p = min_p; p <= max_p; p++) {
+ struct __1_page_stripe *_1ps = &sp2d->_1p_stripes[p];
+ struct page **pp = &_1ps->pages[c];
+ bool uptodate;
+
+ if (*pp)
+ /* to-be-written pages start here */
+ goto read_last_stripe;
+
+ *pp = ios->r4w->get_page(ios->private, offset,
+ &uptodate);
+ if (unlikely(!*pp))
+ return -ENOMEM;
+
+ if (!uptodate)
+ _add_to_read_4_write(ios, &read_si, *pp);
+
+ /* Mark read-pages to be cache_released */
+ _1ps->page_is_read[c] = true;
+ read_si.obj_offset += PAGE_SIZE;
+ offset += PAGE_SIZE;
+ }
+ offset += (sp2d->pages_in_unit - p) * PAGE_SIZE;
+ }
+
+read_last_stripe:
+ offset = ios->offset + (ios->length + PAGE_SIZE - 1) /
+ PAGE_SIZE * PAGE_SIZE;
+ last_stripe_end = div_u64(offset + bytes_in_stripe - 1, bytes_in_stripe)
+ * bytes_in_stripe;
+ if (offset == last_stripe_end) /* Optimize for the aligned case */
+ 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);
+
+ BUG_ON(ios->si.first_stripe_start + bytes_in_stripe != last_stripe_end);
+ /* unaligned IO must be within a single stripe */
+
+ if (min_p == sp2d->pages_in_unit) {
+ /* Didn't do it yet */
+ min_p = _sp2d_min_pg(sp2d);
+ max_p = _sp2d_max_pg(sp2d);
+ }
+
+ while (offset < last_stripe_end) {
+ struct __1_page_stripe *_1ps = &sp2d->_1p_stripes[p];
+
+ if ((min_p <= p) && (p <= max_p)) {
+ struct page *page;
+ bool uptodate;
+
+ BUG_ON(_1ps->pages[c]);
+ page = ios->r4w->get_page(ios->private, offset,
+ &uptodate);
+ if (unlikely(!page))
+ return -ENOMEM;
+
+ _1ps->pages[c] = page;
+ /* Mark read-pages to be cache_released */
+ _1ps->page_is_read[c] = true;
+ if (!uptodate)
+ _add_to_read_4_write(ios, &read_si, page);
+ }
+
+ offset += PAGE_SIZE;
+ if (p == (sp2d->pages_in_unit - 1)) {
+ ++c;
+ p = 0;
+ ore_calc_stripe_info(ios->layout, offset, 0, &read_si);
+ } else {
+ read_si.obj_offset += PAGE_SIZE;
+ ++p;
+ }
+ }
+
+read_it:
+ ios_read = ios->ios_read_4_write;
+ if (!ios_read)
+ return 0;
+
+ /* FIXME: Ugly to signal _sbi_read_mirror that we have bio(s). Change
+ * to check for per_dev->bio
+ */
+ ios_read->pages = ios->pages;
+
+ /* Now read these devices */
+ for (i = 0; i < ios_read->numdevs; i += ios_read->layout->mirrors_p1) {
+ ret = _ore_read_mirror(ios_read, i);
+ if (unlikely(ret))
+ return ret;
+ }
+
+ ret = ore_io_execute(ios_read); /* Synchronus execution */
+ if (unlikely(ret)) {
+ ORE_DBGMSG("!! ore_io_execute => %d\n", ret);
+ return ret;
+ }
+
+ _mark_read4write_pages_uptodate(ios_read, ret);
+ return 0;
+}
+
/* In writes @cur_len means length left. .i.e cur_len==0 is the last parity U */
int _ore_add_parity_unit(struct ore_io_state *ios,
struct ore_striping_info *si,
BUG_ON(per_dev->cur_sg >= ios->sgs_per_dev);
_ore_add_sg_seg(per_dev, cur_len, true);
} else {
+ struct __stripe_pages_2d *sp2d = ios->sp2d;
struct page **pages = ios->parity_pages + ios->cur_par_page;
- unsigned num_pages = ios->layout->stripe_unit / PAGE_SIZE;
+ unsigned num_pages;
unsigned array_start = 0;
unsigned i;
int ret;
+ 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(ios);
+ }
+
for (i = 0; i < num_pages; i++) {
pages[i] = _raid_page_alloc();
if (unlikely(!pages[i]))
return -ENOMEM;
++(ios->cur_par_page);
- /* TODO: only read support for now */
- clear_highpage(pages[i]);
}
- ORE_DBGMSG("writing dev=%d num_pages=%d cur_par_page=%d",
- per_dev->dev, num_pages, ios->cur_par_page);
+ 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,
per_dev, num_pages * PAGE_SIZE);
if (unlikely(ret))
return ret;
+
+ /* TODO: raid6 if (last_parity_dev) */
+ _gen_xor_unit(sp2d);
+ _sp2d_reset(sp2d, ios->r4w, ios->private);
}
return 0;
}
int _ore_post_alloc_raid_stuff(struct ore_io_state *ios)
{
- /*TODO: Only raid writes has stuff to add here */
+ struct ore_layout *layout = ios->layout;
+
+ if (ios->parity_pages) {
+ unsigned pages_in_unit = layout->stripe_unit / PAGE_SIZE;
+ unsigned stripe_size = ios->si.bytes_in_stripe;
+ u64 last_stripe, first_stripe;
+
+ if (_sp2d_alloc(pages_in_unit, layout->group_width,
+ layout->parity, &ios->sp2d)) {
+ return -ENOMEM;
+ }
+
+ BUG_ON(ios->offset % PAGE_SIZE);
+
+ /* Round io down to last full strip */
+ first_stripe = div_u64(ios->offset, stripe_size);
+ last_stripe = div_u64(ios->offset + ios->length, stripe_size);
+
+ /* If an IO spans more then a single stripe it must end at
+ * a stripe boundary. The reminder at the end is pushed into the
+ * next IO.
+ */
+ if (last_stripe != first_stripe) {
+ ios->length = last_stripe * stripe_size - ios->offset;
+
+ BUG_ON(!ios->length);
+ ios->nr_pages = (ios->length + PAGE_SIZE - 1) /
+ PAGE_SIZE;
+ ios->si.length = ios->length; /*make it consistent */
+ }
+ }
return 0;
}
void _ore_free_raid_stuff(struct ore_io_state *ios)
{
- if (ios->parity_pages) { /* writing and raid */
+ if (ios->sp2d) { /* writing and raid */
unsigned i;
for (i = 0; i < ios->cur_par_page; i++) {
}
if (ios->extra_part_alloc)
kfree(ios->parity_pages);
+ /* If IO returned an error pages might need unlocking */
+ _sp2d_reset(ios->sp2d, ios->r4w, ios->private);
+ _sp2d_free(ios->sp2d);
} else {
/* Will only be set if raid reading && sglist is big */
if (ios->extra_part_alloc)
kfree(ios->per_dev[0].sglist);
}
+ if (ios->ios_read_4_write)
+ ore_put_io_state(ios->ios_read_4_write);
}
git.openpandora.org / pandora-kernel.git / commitdiff