From 455682ce547817d75e38028283dc8db00754005d Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Wed, 9 Apr 2014 23:14:38 +0300 Subject: ore: Remove redundant dev_order(), more cleanups Two cleanups: * si->cur_comp, si->cur_pg where always calculated after the call to ore_calc_stripe_info() with the help of _dev_order(...). But these are already calculated by ore_calc_stripe_info() and can be just set there. (This is left over from the time that si->cur_comp, si->cur_pg were only used by raid code, but now the main loop manages them anyway even though they are ultimately not used in none raid code) * si->cur_comp - For the very last stripe case, was set inside _ore_add_parity_unit(). This is not clear and will be wrong for coming raid6 so move this to only caller. Now si->cur_comp is only manipulated within _prepare_for_striping(), always next to the manipulation of cur_dev. Which is much easier to understand and follow. Signed-off-by: Boaz Harrosh --- fs/exofs/ore_raid.h | 18 ------------------ 1 file changed, 18 deletions(-) (limited to 'fs/exofs/ore_raid.h') diff --git a/fs/exofs/ore_raid.h b/fs/exofs/ore_raid.h index 2ffd2c3c6e46..d365bda6beef 100644 --- a/fs/exofs/ore_raid.h +++ b/fs/exofs/ore_raid.h @@ -31,24 +31,6 @@ #define ORE_DBGMSG2(M...) do {} while (0) /* #define ORE_DBGMSG2 ORE_DBGMSG */ -/* Calculate the component order in a stripe. eg the logical data unit - * address within the stripe of @dev given the @par_dev of this stripe. - */ -static inline unsigned _dev_order(unsigned devs_in_group, unsigned mirrors_p1, - unsigned par_dev, unsigned dev) -{ - unsigned first_dev = dev - dev % devs_in_group; - - dev -= first_dev; - par_dev -= first_dev; - - if (devs_in_group == par_dev) /* The raid 0 case */ - return dev / mirrors_p1; - /* raid4/5/6 case */ - return ((devs_in_group + dev - par_dev - mirrors_p1) % devs_in_group) / - mirrors_p1; -} - /* ios_raid.c stuff needed by ios.c */ int _ore_post_alloc_raid_stuff(struct ore_io_state *ios); void _ore_free_raid_stuff(struct ore_io_state *ios); -- cgit v1.2.3 From ce5d36aac26cc395fe3bc45525cdbad3644f01e5 Mon Sep 17 00:00:00 2001 From: Boaz Harrosh Date: Thu, 22 May 2014 14:48:15 +0300 Subject: ore: Support for raid 6 This simple patch adds support for raid6 to the ORE. Most operations and calculations where already for the general case. Only things left: * call async_gen_syndrome() in the case of raid6 (NOTE that the raid6 math is the one supported by the Linux Kernel see: crypto/async_tx/async_pq.c) * call _ore_add_parity_unit() twice with only last call generating the redundancy pages. * Fix couple BUGS in old code a. In reads when parity==2 it can happen that per_dev->length=0 but per_dev->offset was set and adjusted by _ore_add_sg_seg(). Don't let it be overwritten. b. The all 'cur_comp > starting_dev' thing to determine if: "per_dev->offset is in the current stripe number or the next one." Was a complete raid5/4 accident. When parity==2 this is not at all true usually. All we need to do is increment si->ob_offset once we pass by the first parity device. (This also greatly simplifies the code, amen) c. Calculation of si->dev rotation can overflow when parity==2. * Then last enable raid6 in ore_verify_layout() I want to deeply thank Daniel Gryniewicz who found first all the bugs in the old raid code, and inspired these patches: Inspired-by Daniel Gryniewicz Signed-off-by: Boaz Harrosh --- fs/exofs/ore_raid.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) (limited to 'fs/exofs/ore_raid.h') diff --git a/fs/exofs/ore_raid.h b/fs/exofs/ore_raid.h index d365bda6beef..cf6375d82129 100644 --- a/fs/exofs/ore_raid.h +++ b/fs/exofs/ore_raid.h @@ -38,7 +38,8 @@ void _ore_free_raid_stuff(struct ore_io_state *ios); void _ore_add_sg_seg(struct ore_per_dev_state *per_dev, unsigned cur_len, bool not_last); 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); + struct ore_per_dev_state *per_dev, unsigned cur_len, + bool do_xor); void _ore_add_stripe_page(struct __stripe_pages_2d *sp2d, struct ore_striping_info *si, struct page *page); static inline void _add_stripe_page(struct __stripe_pages_2d *sp2d, -- cgit v1.2.3