From fc881fa0d59596c02f8707b5572567c369d4789a Mon Sep 17 00:00:00 2001 From: Joel Becker Date: Fri, 1 Feb 2008 12:04:48 -0800 Subject: ocfs2: De-magic the in-memory slot map. The in-memory slot map uses the same magic as the on-disk one. There is a special value to mark a slot as invalid. It relies on the size of certain types and so on. Write a new in-memory map that keeps validity as a separate field. Outside of the I/O functions, OCFS2_INVALID_SLOT now means what it is supposed to. It also is no longer tied to the type size. This also means that only the I/O functions refer to 16bit quantities. Signed-off-by: Joel Becker Signed-off-by: Mark Fasheh --- fs/ocfs2/slot_map.c | 130 +++++++++++++++++++++++++++++----------------------- 1 file changed, 72 insertions(+), 58 deletions(-) (limited to 'fs/ocfs2/slot_map.c') diff --git a/fs/ocfs2/slot_map.c b/fs/ocfs2/slot_map.c index 5bddee110091..65a61bfa3f2e 100644 --- a/fs/ocfs2/slot_map.c +++ b/fs/ocfs2/slot_map.c @@ -42,21 +42,41 @@ #include "buffer_head_io.h" + +struct ocfs2_slot { + int sl_valid; + unsigned int sl_node_num; +}; + struct ocfs2_slot_info { struct inode *si_inode; unsigned int si_blocks; struct buffer_head **si_bh; unsigned int si_num_slots; - unsigned int si_size; - s16 si_global_node_nums[OCFS2_MAX_SLOTS]; + struct ocfs2_slot *si_slots; }; -static s16 __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si, - s16 global); -static void __ocfs2_fill_slot(struct ocfs2_slot_info *si, - s16 slot_num, - s16 node_num); +static int __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si, + unsigned int node_num); + +static void ocfs2_invalidate_slot(struct ocfs2_slot_info *si, + int slot_num) +{ + BUG_ON((slot_num < 0) || (slot_num >= si->si_num_slots)); + si->si_slots[slot_num].sl_valid = 0; +} + +static void ocfs2_set_slot(struct ocfs2_slot_info *si, + int slot_num, unsigned int node_num) +{ + BUG_ON((slot_num < 0) || (slot_num >= si->si_num_slots)); + BUG_ON((node_num == O2NM_INVALID_NODE_NUM) || + (node_num >= O2NM_MAX_NODES)); + + si->si_slots[slot_num].sl_valid = 1; + si->si_slots[slot_num].sl_node_num = node_num; +} /* * Post the slot information on disk into our slot_info struct. @@ -71,8 +91,12 @@ static void ocfs2_update_slot_info(struct ocfs2_slot_info *si) * should've made sure we have the most recent copy. */ disk_info = (__le16 *) si->si_bh[0]->b_data; - for (i = 0; i < si->si_size; i++) - si->si_global_node_nums[i] = le16_to_cpu(disk_info[i]); + for (i = 0; i < si->si_num_slots; i++) { + if (le16_to_cpu(disk_info[i]) == (u16)OCFS2_INVALID_SLOT) + ocfs2_invalidate_slot(si, i); + else + ocfs2_set_slot(si, i, le16_to_cpu(disk_info[i])); + } } int ocfs2_refresh_slot_info(struct ocfs2_super *osb) @@ -114,8 +138,13 @@ static int ocfs2_update_disk_slots(struct ocfs2_super *osb, __le16 *disk_info = (__le16 *) si->si_bh[0]->b_data; spin_lock(&osb->osb_lock); - for (i = 0; i < si->si_size; i++) - disk_info[i] = cpu_to_le16(si->si_global_node_nums[i]); + for (i = 0; i < si->si_num_slots; i++) { + if (si->si_slots[i].sl_valid) + disk_info[i] = + cpu_to_le16(si->si_slots[i].sl_node_num); + else + disk_info[i] = cpu_to_le16(OCFS2_INVALID_SLOT); + } spin_unlock(&osb->osb_lock); status = ocfs2_write_block(osb, si->si_bh[0], si->si_inode); @@ -147,39 +176,39 @@ static int ocfs2_slot_map_physical_size(struct ocfs2_super *osb, return 0; } -/* try to find global node in the slot info. Returns - * OCFS2_INVALID_SLOT if nothing is found. */ -static s16 __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si, - s16 global) +/* try to find global node in the slot info. Returns -ENOENT + * if nothing is found. */ +static int __ocfs2_node_num_to_slot(struct ocfs2_slot_info *si, + unsigned int node_num) { - int i; - s16 ret = OCFS2_INVALID_SLOT; + int i, ret = -ENOENT; for(i = 0; i < si->si_num_slots; i++) { - if (global == si->si_global_node_nums[i]) { - ret = (s16) i; + if (si->si_slots[i].sl_valid && + (node_num == si->si_slots[i].sl_node_num)) { + ret = i; break; } } + return ret; } -static s16 __ocfs2_find_empty_slot(struct ocfs2_slot_info *si, - s16 preferred) +static int __ocfs2_find_empty_slot(struct ocfs2_slot_info *si, + int preferred) { - int i; - s16 ret = OCFS2_INVALID_SLOT; + int i, ret = -ENOSPC; - if (preferred >= 0 && preferred < si->si_num_slots) { - if (OCFS2_INVALID_SLOT == si->si_global_node_nums[preferred]) { + if ((preferred >= 0) && (preferred < si->si_num_slots)) { + if (!si->si_slots[preferred].sl_valid) { ret = preferred; goto out; } } for(i = 0; i < si->si_num_slots; i++) { - if (OCFS2_INVALID_SLOT == si->si_global_node_nums[i]) { - ret = (s16) i; + if (!si->si_slots[i].sl_valid) { + ret = i; break; } } @@ -189,16 +218,13 @@ out: int ocfs2_node_num_to_slot(struct ocfs2_super *osb, unsigned int node_num) { - s16 slot; + int slot; struct ocfs2_slot_info *si = osb->slot_info; spin_lock(&osb->osb_lock); slot = __ocfs2_node_num_to_slot(si, node_num); spin_unlock(&osb->osb_lock); - if (slot == OCFS2_INVALID_SLOT) - return -ENOENT; - return slot; } @@ -212,10 +238,10 @@ int ocfs2_slot_to_node_num_locked(struct ocfs2_super *osb, int slot_num, BUG_ON(slot_num < 0); BUG_ON(slot_num > osb->max_slots); - if (si->si_global_node_nums[slot_num] == OCFS2_INVALID_SLOT) + if (!si->si_slots[slot_num].sl_valid) return -ENOENT; - *node_num = si->si_global_node_nums[slot_num]; + *node_num = si->si_slots[slot_num].sl_node_num; return 0; } @@ -241,19 +267,7 @@ static void __ocfs2_free_slot_info(struct ocfs2_slot_info *si) kfree(si); } -static void __ocfs2_fill_slot(struct ocfs2_slot_info *si, - s16 slot_num, - s16 node_num) -{ - BUG_ON(slot_num == OCFS2_INVALID_SLOT); - BUG_ON(slot_num >= si->si_num_slots); - BUG_ON((node_num != O2NM_INVALID_NODE_NUM) && - (node_num >= O2NM_MAX_NODES)); - - si->si_global_node_nums[slot_num] = node_num; -} - -int ocfs2_clear_slot(struct ocfs2_super *osb, s16 slot_num) +int ocfs2_clear_slot(struct ocfs2_super *osb, int slot_num) { struct ocfs2_slot_info *si = osb->slot_info; @@ -261,7 +275,7 @@ int ocfs2_clear_slot(struct ocfs2_super *osb, s16 slot_num) return 0; spin_lock(&osb->osb_lock); - __ocfs2_fill_slot(si, slot_num, OCFS2_INVALID_SLOT); + ocfs2_invalidate_slot(si, slot_num); spin_unlock(&osb->osb_lock); return ocfs2_update_disk_slots(osb, osb->slot_info); @@ -324,11 +338,13 @@ bail: int ocfs2_init_slot_info(struct ocfs2_super *osb) { - int status, i; + int status; struct inode *inode = NULL; struct ocfs2_slot_info *si; - si = kzalloc(sizeof(struct ocfs2_slot_info), GFP_KERNEL); + si = kzalloc(sizeof(struct ocfs2_slot_info) + + (sizeof(struct ocfs2_slot) * osb->max_slots), + GFP_KERNEL); if (!si) { status = -ENOMEM; mlog_errno(status); @@ -336,10 +352,8 @@ int ocfs2_init_slot_info(struct ocfs2_super *osb) } si->si_num_slots = osb->max_slots; - si->si_size = OCFS2_MAX_SLOTS; - - for(i = 0; i < si->si_num_slots; i++) - si->si_global_node_nums[i] = OCFS2_INVALID_SLOT; + si->si_slots = (struct ocfs2_slot *)((char *)si + + sizeof(struct ocfs2_slot_info)); inode = ocfs2_get_system_file_inode(osb, SLOT_MAP_SYSTEM_INODE, OCFS2_INVALID_SLOT); @@ -375,7 +389,7 @@ void ocfs2_free_slot_info(struct ocfs2_super *osb) int ocfs2_find_slot(struct ocfs2_super *osb) { int status; - s16 slot; + int slot; struct ocfs2_slot_info *si; mlog_entry_void(); @@ -390,11 +404,11 @@ int ocfs2_find_slot(struct ocfs2_super *osb) * own journal recovery? Possibly not, though we certainly * need to warn to the user */ slot = __ocfs2_node_num_to_slot(si, osb->node_num); - if (slot == OCFS2_INVALID_SLOT) { + if (slot < 0) { /* if no slot yet, then just take 1st available * one. */ slot = __ocfs2_find_empty_slot(si, osb->preferred_slot); - if (slot == OCFS2_INVALID_SLOT) { + if (slot < 0) { spin_unlock(&osb->osb_lock); mlog(ML_ERROR, "no free slots available!\n"); status = -EINVAL; @@ -404,7 +418,7 @@ int ocfs2_find_slot(struct ocfs2_super *osb) mlog(ML_NOTICE, "slot %d is already allocated to this node!\n", slot); - __ocfs2_fill_slot(si, slot, osb->node_num); + ocfs2_set_slot(si, slot, osb->node_num); osb->slot_num = slot; spin_unlock(&osb->osb_lock); @@ -430,7 +444,7 @@ void ocfs2_put_slot(struct ocfs2_super *osb) spin_lock(&osb->osb_lock); ocfs2_update_slot_info(si); - __ocfs2_fill_slot(si, osb->slot_num, OCFS2_INVALID_SLOT); + ocfs2_invalidate_slot(si, osb->slot_num); osb->slot_num = OCFS2_INVALID_SLOT; spin_unlock(&osb->osb_lock); -- cgit