[PATCH v2] lightnvm: pblk: consider max hw sectors supported for max_write_pgs

[Zhoujie Wu]

When do GC, the number of read/write sectors are determined
by max_write_pgs(see gc_rq preparation in pblk_gc_line_prepare_ws).

Due to max_write_pgs doesn't consider max hw sectors
supported by nvme controller(128K), which leads to GC
tries to read 64 * 4K in one command, and see below error
caused by pblk_bio_map_addr in function pblk_submit_read_gc.

[ 2923.005376] pblk: could not add page to bio
[ 2923.005377] pblk: could not allocate GC bio (18446744073709551604)

Signed-off-by: Zhoujie Wu <z...@marvell.com>
---
v2: Changed according to Javier's comments.
Remove unneccessary comment and move the definition of bqueue to
maintain ordering.

 drivers/lightnvm/pblk-init.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/lightnvm/pblk-init.c b/drivers/lightnvm/pblk-init.c
index e357388..0ef9ac5 100644
--- a/drivers/lightnvm/pblk-init.c
+++ b/drivers/lightnvm/pblk-init.c
@@ -391,6 +391,7 @@ static void pblk_put_global_caches(void)
 static int pblk_core_init(struct pblk *pblk)
 {
        struct nvm_tgt_dev *dev = pblk->dev;
+       struct request_queue *bqueue = dev->q;
        struct nvm_geo *geo = &dev->geo;
        int ret, max_write_ppas;
 
@@ -407,6 +408,8 @@ static int pblk_core_init(struct pblk *pblk)
        pblk->min_write_pgs = geo->ws_opt;
        max_write_ppas = pblk->min_write_pgs * geo->all_luns;
        pblk->max_write_pgs = min_t(int, max_write_ppas, NVM_MAX_VLBA);
+       pblk->max_write_pgs =  min_t(int, pblk->max_write_pgs,
+               queue_max_hw_sectors(bqueue) / (geo->csecs >> 9));
        pblk_set_sec_per_write(pblk, pblk->min_write_pgs);
 
        pblk->pad_dist = kcalloc(pblk->min_write_pgs - 1, sizeof(atomic64_t),
-- 
1.9.1