From: Mingming Cao ext3_rsv_base.patch: Implements the base of in-memory block reservation and block allocation from reservation window. -basic reservation structure and operations -reservation based ext3 block allocation --- 25-akpm/fs/ext3/balloc.c | 566 +++++++++++++++++++++++++++++++++---- 25-akpm/fs/ext3/file.c | 2 25-akpm/fs/ext3/ialloc.c | 4 25-akpm/fs/ext3/inode.c | 9 25-akpm/fs/ext3/super.c | 7 25-akpm/include/linux/ext3_fs.h | 6 25-akpm/include/linux/ext3_fs_i.h | 12 25-akpm/include/linux/ext3_fs_sb.h | 4 8 files changed, 556 insertions(+), 54 deletions(-) diff -puN fs/ext3/balloc.c~ext3_rsv_base fs/ext3/balloc.c --- 25/fs/ext3/balloc.c~ext3_rsv_base 2004-04-14 18:58:18.915589536 -0700 +++ 25-akpm/fs/ext3/balloc.c 2004-04-14 18:58:18.932586952 -0700 @@ -96,9 +96,86 @@ read_block_bitmap(struct super_block *sb error_out: return bh; } +/* + * The reservation window structure operations + * -------------------------------------------- + * Operations include: + * dump, find, add, remove, is_empty, find_next_reservable_window, etc. + * + * We use sorted double linked list for the per-filesystem reservation + * window list. (like in vm_region). + * + * Initially, we keep those small operations in the abstract functions, + * so later if we need a better searching tree than double linked-list, + * we could easily switch to that without changing too much + * code. + */ +static inline void rsv_window_dump(struct reserve_window *head, char *fn) +{ + struct reserve_window *rsv; + + printk("Block Allocation Reservation Windows Map (%s):\n", fn); + list_for_each_entry(rsv, &head->rsv_list, rsv_list) { + printk("reservation window 0x%p start: %d, end: %d\n", + rsv, rsv->rsv_start, rsv->rsv_end); + } +} + +static int +goal_in_my_reservation(struct reserve_window *rsv, int goal, + unsigned int group, struct super_block * sb) +{ + unsigned long group_first_block, group_last_block; + + group_first_block = le32_to_cpu(EXT3_SB(sb)->s_es->s_first_data_block) + + group * EXT3_BLOCKS_PER_GROUP(sb); + group_last_block = group_first_block + EXT3_BLOCKS_PER_GROUP(sb) - 1; + + if ((rsv->rsv_start > group_last_block) || + (rsv->rsv_end < group_first_block)) + return 0; + if ((goal >= 0) && ((goal + group_first_block < rsv->rsv_start) + || (goal + group_first_block > rsv->rsv_end))) + return 0; + return 1; +} + +static inline void rsv_window_add(struct reserve_window *rsv, + struct reserve_window *prev) +{ + /* insert the new reservation window after the head */ + list_add(&rsv->rsv_list, &prev->rsv_list); +} + +static inline void rsv_window_remove(struct reserve_window *rsv) +{ + rsv->rsv_start = 0; + rsv->rsv_end = 0; + list_del(&rsv->rsv_list); + INIT_LIST_HEAD(&rsv->rsv_list); +} + +static inline int rsv_is_empty(struct reserve_window *rsv) +{ + /* a valid reservation end block could not be 0 */ + return (rsv->rsv_end == 0); +} + +void ext3_discard_reservation(struct inode *inode) +{ + struct ext3_inode_info *ei = EXT3_I(inode); + struct reserve_window *rsv = &ei->i_rsv_window; + spinlock_t *rsv_lock = &EXT3_SB(inode->i_sb)->s_rsv_window_lock; + + if (!rsv_is_empty(rsv)) { + spin_lock(rsv_lock); + rsv_window_remove(rsv); + spin_unlock(rsv_lock); + } +} /* Free given blocks, update quota and i_blocks field */ -void ext3_free_blocks (handle_t *handle, struct inode * inode, +void ext3_free_blocks(handle_t *handle, struct inode *inode, unsigned long block, unsigned long count) { struct buffer_head *bitmap_bh = NULL; @@ -296,7 +373,7 @@ error_return: * data-writes at some point, and disable it for metadata allocations or * sync-data inodes. */ -static inline int ext3_test_allocatable(int nr, struct buffer_head *bh) +static int ext3_test_allocatable(int nr, struct buffer_head *bh) { int ret; struct journal_head *jh = bh2jh(bh); @@ -313,6 +390,33 @@ static inline int ext3_test_allocatable( return ret; } +static int +bitmap_search_next_usable_block(int start, struct buffer_head *bh, + int maxblocks) +{ + int next; + struct journal_head *jh = bh2jh(bh); + + /* + * The bitmap search --- search forward alternately through the actual + * bitmap and the last-committed copy until we find a bit free in + * both + */ + while (start < maxblocks) { + next = ext3_find_next_zero_bit(bh->b_data, maxblocks, start); + if (next >= maxblocks) + return -1; + if (ext3_test_allocatable(next, bh)) + return next; + jbd_lock_bh_state(bh); + if (jh->b_committed_data) + start = ext3_find_next_zero_bit(jh->b_committed_data, + maxblocks, next); + jbd_unlock_bh_state(bh); + } + return -1; +} + /* * Find an allocatable block in a bitmap. We honour both the bitmap and * its last-committed copy (if that exists), and perform the "most @@ -325,7 +429,6 @@ find_next_usable_block(int start, struct { int here, next; char *p, *r; - struct journal_head *jh = bh2jh(bh); if (start > 0) { /* @@ -337,6 +440,8 @@ find_next_usable_block(int start, struct * next 64-bit boundary is simple.. */ int end_goal = (start + 63) & ~63; + if (end_goal > maxblocks) + end_goal = maxblocks; here = ext3_find_next_zero_bit(bh->b_data, end_goal, start); if (here < end_goal && ext3_test_allocatable(here, bh)) return here; @@ -359,19 +464,8 @@ find_next_usable_block(int start, struct * bitmap and the last-committed copy until we find a bit free in * both */ - while (here < maxblocks) { - next = ext3_find_next_zero_bit(bh->b_data, maxblocks, here); - if (next >= maxblocks) - return -1; - if (ext3_test_allocatable(next, bh)) - return next; - jbd_lock_bh_state(bh); - if (jh->b_committed_data) - here = ext3_find_next_zero_bit(jh->b_committed_data, - maxblocks, next); - jbd_unlock_bh_state(bh); - } - return -1; + here = bitmap_search_next_usable_block(here, bh, maxblocks); + return here; } /* @@ -407,62 +501,429 @@ claim_block(spinlock_t *lock, int block, */ static int ext3_try_to_allocate(struct super_block *sb, handle_t *handle, int group, - struct buffer_head *bitmap_bh, int goal, int *errp) + struct buffer_head *bitmap_bh, int goal, struct reserve_window *my_rsv) { - int i; - int fatal; - int credits = 0; + int group_first_block, start, end; - *errp = 0; - - /* - * Make sure we use undo access for the bitmap, because it is critical - * that we do the frozen_data COW on bitmap buffers in all cases even - * if the buffer is in BJ_Forget state in the committing transaction. - */ - BUFFER_TRACE(bitmap_bh, "get undo access for new block"); - fatal = ext3_journal_get_undo_access(handle, bitmap_bh, &credits); - if (fatal) { - *errp = fatal; - goto fail; + /* we do allocation within the reservation window if we have a window */ + if (my_rsv) { + group_first_block = + le32_to_cpu(EXT3_SB(sb)->s_es->s_first_data_block) + + group * EXT3_BLOCKS_PER_GROUP(sb); + if (my_rsv->rsv_start >= group_first_block) + start = my_rsv->rsv_start - group_first_block; + else + /* reservation window cross group boundary */ + start = 0; + end = my_rsv->rsv_end - group_first_block + 1; + if (end > EXT3_BLOCKS_PER_GROUP(sb)) + /* reservation window crosses group boundary */ + end = EXT3_BLOCKS_PER_GROUP(sb); + if ((start <= goal) && (goal < end)) + start = goal; + else + goal = -1; + } else { + if (goal > 0) + start = goal; + else + start = 0; + end = EXT3_BLOCKS_PER_GROUP(sb); } + BUG_ON(start > EXT3_BLOCKS_PER_GROUP(sb)); + repeat: if (goal < 0 || !ext3_test_allocatable(goal, bitmap_bh)) { - goal = find_next_usable_block(goal, bitmap_bh, - EXT3_BLOCKS_PER_GROUP(sb)); + goal = find_next_usable_block(start, bitmap_bh, end); if (goal < 0) goto fail_access; - - for (i = 0; i < 7 && goal > 0 && - ext3_test_allocatable(goal - 1, bitmap_bh); - i++, goal--); } + start = goal; if (!claim_block(sb_bgl_lock(EXT3_SB(sb), group), goal, bitmap_bh)) { /* * The block was allocated by another thread, or it was * allocated and then freed by another thread */ + start++; goal++; - if (goal >= EXT3_BLOCKS_PER_GROUP(sb)) + if (start >= end) goto fail_access; goto repeat; } - BUFFER_TRACE(bitmap_bh, "journal_dirty_metadata for bitmap block"); - fatal = ext3_journal_dirty_metadata(handle, bitmap_bh); + return goal; +fail_access: + return -1; +} + +/** + * find_next_reservable_window(): + * find a reservable space within the given range + * It does not allocate the reservation window for now + * alloc_new_reservation() will do the work later. + * + * @search_head: the head of the searching list; + * This is not necessary the list head of the whole filesystem + * + * we have both head and start_block to assist the search + * for the reservable space. The list start from head, + * but we will shift to the place where start_block is, + * then start from there, we looking for a resevable space. + * + * @fs_rsv_head: per-filesystem reervation list head. + * + * @size: the target new reservation window size + * @group_first_block: the first block we consider to start + * the real search from + * + * @last_block: + * the maxium block number that our goal reservable space + * could start from. This is normally the last block in this + * group. The search will end when we found the start of next + * possiblereservable space is out of this boundary. + * This could handle the cross bounday reservation window request. + * + * basically we search from the given range, rather than the whole + * reservation double linked list, (start_block, last_block) + * to find a free region that of of my size and has not + * been reserved. + * + * on succeed, it returns the reservation window to be append to. + * failed, return NULL. + */ +static inline +struct reserve_window *find_next_reservable_window( + struct reserve_window *search_head, + struct reserve_window *fs_rsv_head, + unsigned long size, int *start_block, + int last_block) +{ + struct reserve_window *rsv; + int cur; + + /* TODO:make the start of the reservation window byte alligned */ + /*cur = *start_block & 8;*/ + cur = *start_block; + rsv = list_entry(search_head->rsv_list.next, + struct reserve_window, rsv_list); + while (rsv != fs_rsv_head) { + if (cur + size <= rsv->rsv_start) { + /* + * Found a reserveable space big enough. We could + * have a reservation across the group boundary here + */ + break; + } + if (cur <= rsv->rsv_end) + cur = rsv->rsv_end + 1; + + /* TODO? + * in the case we could not find a reservable space + * that is what is expected, during the re-search, we could + * remember what's the largest reservable space we could have + * and return that one. + * + * For now it will fail if we could not find the reservable + * space with expected-size (or more)... + */ + rsv = list_entry(rsv->rsv_list.next, + struct reserve_window, rsv_list); + if (cur > last_block) + return NULL; /* fail */ + } + /* + * we come here either : + * when we rearch to the end of the whole list, + * and there is empty reservable space after last entry in the list. + * append it to the end of the list. + * + * or we found one reservable space in the middle of the list, + * return the reservation window that we could append to. + * succeed. + */ + *start_block = cur; + return list_entry(rsv->rsv_list.prev, struct reserve_window, rsv_list); +} + +/** + * alloc_new_reservation()--allocate a new reservation window + * if there is an existing reservation, discard it first + * then allocate the new one from there + * otherwise allocate the new reservation from the given + * start block, or the beginning of the group, if a goal + * is not given. + * + * To make a new reservation, we search part of the filesystem + * reservation list(the list that inside the group). + * + * If we have a old reservation, the search goal is the end of + * last reservation. If we do not have a old reservatio, then we + * start from a given goal, or the first block of the group, if + * the goal is not given. + * + * We first find a reservable space after the goal, then from + * there,we check the bitmap for the first free block after + * it. If there is no free block until the end of group, then the + * whole group is full, we failed. Otherwise, check if the free + * block is inside the expected reservable space, if so, we + * succeed. + * If the first free block is outside the reseravle space, then + * start from the first free block, we search for next avalibale + * space, and go on. + * + * on succeed, a new reservation will be found and inserted into the list + * It contains at least one free block, and it is not overlap with other + * reservation window. + * + * failed: we failed to found a reservation window in this group + * + * @rsv: the reservation + * + * @goal: The goal. It is where the search for a + * free reservable space should start from. + * if we have a old reservation, start_block is the end of + * old reservation. Otherwise, + * if we have a goal(goal >0 ), then start from there, + * no goal(goal = -1), we start from the first block + * of the group. + * + * @sb: the super block + * @group: the group we are trying to do allocate in + * @bitmap_bh: the block group block bitmap + */ +static int alloc_new_reservation(struct reserve_window *my_rsv, + int goal, struct super_block *sb, + unsigned int group, struct buffer_head *bitmap_bh) +{ + struct reserve_window *search_head; + int group_first_block, group_end_block, start_block; + int first_free_block; + int reservable_space_start; + struct reserve_window *prev_rsv; + struct reserve_window *fs_rsv_head = &EXT3_SB(sb)->s_rsv_window_head; + unsigned long size; + + group_first_block = le32_to_cpu(EXT3_SB(sb)->s_es->s_first_data_block) + + group * EXT3_BLOCKS_PER_GROUP(sb); + group_end_block = group_first_block + EXT3_BLOCKS_PER_GROUP(sb) - 1; + + if (goal < 0) + start_block = group_first_block; + else + start_block = goal + group_first_block; + + size = my_rsv->rsv_goal_size; + /* if we have a old reservation, discard it first */ + if (!rsv_is_empty(my_rsv)) { + /* + * if the old reservation is cross group boundary + * we will come here when we just failed to allocate from + * the first part of the window. We still have another part + * that belongs to the next group. In this case, there is no + * point to discard our window and try to allocate a new one + * in this group(which will fail). we should + * keep the reservation window, just simply move on. + * + * Maybe we could shift the start block of the reservation + * window to the first block of next group. + */ + + if ((my_rsv->rsv_start <= group_end_block) && + (my_rsv->rsv_end > group_end_block)) + return -1; + + /* remember where we are before we discard the old one */ + if (my_rsv->rsv_end + 1 > start_block) + start_block = my_rsv->rsv_end + 1; + search_head = list_entry(my_rsv->rsv_list.prev, + struct reserve_window, rsv_list); + rsv_window_remove(my_rsv); + } + else { + /* + * we don't have a reservation, + * we set our goal(start_block) and + * the list head for the search + */ + search_head = fs_rsv_head; + } + + /* + * find_next_reservable_window() simply find a reservable window + * inside the given range(start_block, group_end_block). + * + * To make sure the reservation window has a free bit inside it, we + * need to check the bitmap after we found a reservable window. + */ +retry: + prev_rsv = find_next_reservable_window(search_head, fs_rsv_head, size, + &start_block, group_end_block); + if (prev_rsv == NULL) + goto failed; + reservable_space_start = start_block; + /* + * On success, find_next_reservable_window() returns the + * reservation window where there is a reservable space after it. + * Before we reserve this reservable space, we need + * to make sure there is at least a free block inside this region. + * + * searching the first free bit on the block bitmap and copy of + * last committed bitmap alternatively, until we found a allocatable + * block. Search start from the start block of the reservable space + * we just found. + */ + first_free_block = bitmap_search_next_usable_block( + reservable_space_start - group_first_block, + bitmap_bh, group_end_block - group_first_block + 1); + + if (first_free_block < 0) { + /* + * no free block left on the bitmap, no point + * to reserve the space. return failed. + */ + goto failed; + } + start_block = first_free_block + group_first_block; + /* + * check if the first free block is within the + * free space we just found + */ + if ((start_block >= reservable_space_start) && + (start_block < reservable_space_start + size)) + goto found_rsv_window; + /* + * if the first free bit we found is out of the reservable space + * this means there is no free block on the reservable space + * we should continue search for next reservable space, + * start from where the free block is, + * we also shift the list head to where we stopped last time + */ + search_head = prev_rsv; + goto retry; + +found_rsv_window: + /* + * great! the reservable space contains some free blocks. + * Insert it to the list. + */ + rsv_window_add(my_rsv, prev_rsv); + my_rsv->rsv_start = reservable_space_start; + my_rsv->rsv_end = my_rsv->rsv_start + size - 1; + return 0; /* succeed */ +failed: + return -1; /* failed */ +} + +/* + * This is the main function used to allocate a new block and its reservation + * window. + * + * Each time when a new block allocation is need, first try to allocate from + * its own reservation. If it does not have a reservation window, instead of + * looking for a free bit on bitmap first, then look up the reservation list to + * see if it is inside somebody else's reservation window, we try to allocate a + * reservation window for it start from the goal first. Then do the block + * allocation within the reservation window. + * + * This will aviod keep searching the reservation list again and again when + * someboday is looking for a free block(without reservation), and there are + * lots of free blocks, but they are all being reserved + * + * We use a sorted double linked list for the per-filesystem reservation list. + * The insert, remove and find a free space(non-reserved) operations for the + * sorted double linked list should be fast. + * + */ +static int +ext3_try_to_allocate_with_rsv(struct super_block *sb, handle_t *handle, + unsigned int group, struct buffer_head *bitmap_bh, + int goal, struct reserve_window * my_rsv, + int *errp) +{ + spinlock_t *rsv_lock; + unsigned long group_first_block; + int ret = 0; + int fatal; + int credits = 0; + + *errp = 0; + + /* + * Make sure we use undo access for the bitmap, because it is critical + * that we do the frozen_data COW on bitmap buffers in all cases even + * if the buffer is in BJ_Forget state in the committing transaction. + */ + BUFFER_TRACE(bitmap_bh, "get undo access for new block"); + fatal = ext3_journal_get_undo_access(handle, bitmap_bh, &credits); if (fatal) { *errp = fatal; - goto fail; + return -1; + } + +#ifdef EXT3_RESERVATION + rsv_lock = &EXT3_SB(sb)->s_rsv_window_lock; + /* + * goal is a group relative block number (if there is a goal) + * 0 < goal < EXT3_BLOCKS_PER_GROUP(sb) + * first block is a filesystem wide block number + * first block is the block number of the first block in this group + */ + group_first_block = le32_to_cpu(EXT3_SB(sb)->s_es->s_first_data_block) + + group * EXT3_BLOCKS_PER_GROUP(sb); + + /* + * Basically we will allocate a new block from inode's reservation + * window. + * + * We need to allocate a new reservation window, if: + * a) inode does not have a reservation window; or + * b) last attemp of allocating a block from existing reservation + * failed; or + * c) we come here with a goal and with a reservation window + * + * We do not need to allocate a new reservation window if we come here + * at the beginning with a goal and the goal is inside the window, or + * or we don't have a goal but already have a reservation window. + * then we could go to allocate from the reservation window directly. + */ + while (1) { + if (rsv_is_empty(my_rsv) || (ret < 0) || + !goal_in_my_reservation(my_rsv, goal, group, sb)) { + spin_lock(rsv_lock); + ret = alloc_new_reservation(my_rsv, goal, sb, + group, bitmap_bh); + spin_unlock(rsv_lock); + if (ret < 0) + break; /* failed */ + + if (!goal_in_my_reservation(my_rsv, goal, group, sb)) + goal = -1; + } + ret = ext3_try_to_allocate(sb, handle, group, bitmap_bh, goal, + my_rsv); + if (ret >= 0) + break; /* succeed */ + } +#else + ret = ext3_try_to_allocate(sb, handle, group, bitmap_bh, goal, NULL); +#endif + + if (ret >= 0) { + BUFFER_TRACE(bitmap_bh, "journal_dirty_metadata for " + "bitmap block"); + fatal = ext3_journal_dirty_metadata(handle, bitmap_bh); + if (fatal) { + *errp = fatal; + return -1; + } + return ret; } - return goal; -fail_access: BUFFER_TRACE(bitmap_bh, "journal_release_buffer"); ext3_journal_release_buffer(handle, bitmap_bh, credits); -fail: - return -1; + return ret; } /* @@ -473,8 +934,8 @@ fail: * bitmap, and then for any free bit if that fails. * This function also updates quota and i_blocks field. */ -int -ext3_new_block(handle_t *handle, struct inode *inode, unsigned long goal, int *errp) +int ext3_new_block(handle_t *handle, struct inode *inode, + unsigned long goal, int *errp) { struct buffer_head *bitmap_bh = NULL; /* bh */ struct buffer_head *gdp_bh; /* bh2 */ @@ -489,6 +950,7 @@ ext3_new_block(handle_t *handle, struct struct ext3_group_desc *gdp; struct ext3_super_block *es; struct ext3_sb_info *sbi; + struct reserve_window *my_rsv = &EXT3_I(inode)->i_rsv_window; #ifdef EXT3FS_DEBUG static int goal_hits, goal_attempts; #endif @@ -539,8 +1001,8 @@ ext3_new_block(handle_t *handle, struct bitmap_bh = read_block_bitmap(sb, group_no); if (!bitmap_bh) goto io_error; - ret_block = ext3_try_to_allocate(sb, handle, group_no, - bitmap_bh, ret_block, &fatal); + ret_block = ext3_try_to_allocate_with_rsv(sb, handle, group_no, + bitmap_bh, ret_block, my_rsv, &fatal); if (fatal) goto out; if (ret_block >= 0) @@ -568,8 +1030,8 @@ ext3_new_block(handle_t *handle, struct bitmap_bh = read_block_bitmap(sb, group_no); if (!bitmap_bh) goto io_error; - ret_block = ext3_try_to_allocate(sb, handle, group_no, - bitmap_bh, -1, &fatal); + ret_block = ext3_try_to_allocate_with_rsv(sb, handle, group_no, + bitmap_bh, -1, my_rsv, &fatal); if (fatal) goto out; if (ret_block >= 0) diff -puN fs/ext3/file.c~ext3_rsv_base fs/ext3/file.c --- 25/fs/ext3/file.c~ext3_rsv_base 2004-04-14 18:58:18.917589232 -0700 +++ 25-akpm/fs/ext3/file.c 2004-04-14 18:58:18.932586952 -0700 @@ -33,6 +33,8 @@ */ static int ext3_release_file (struct inode * inode, struct file * filp) { + if (filp->f_mode & FMODE_WRITE) + ext3_discard_reservation(inode); if (is_dx(inode) && filp->private_data) ext3_htree_free_dir_info(filp->private_data); diff -puN fs/ext3/ialloc.c~ext3_rsv_base fs/ext3/ialloc.c --- 25/fs/ext3/ialloc.c~ext3_rsv_base 2004-04-14 18:58:18.918589080 -0700 +++ 25-akpm/fs/ext3/ialloc.c 2004-04-14 18:58:18.933586800 -0700 @@ -581,6 +581,10 @@ got: ei->i_file_acl = 0; ei->i_dir_acl = 0; ei->i_dtime = 0; + ei->i_rsv_window.rsv_start = 0; + ei->i_rsv_window.rsv_end= 0; + ei->i_rsv_window.rsv_goal_size = EXT3_DEFAULT_RESERVE_BLOCKS; + INIT_LIST_HEAD(&ei->i_rsv_window.rsv_list); ei->i_block_group = group; ext3_set_inode_flags(inode); diff -puN fs/ext3/inode.c~ext3_rsv_base fs/ext3/inode.c --- 25/fs/ext3/inode.c~ext3_rsv_base 2004-04-14 18:58:18.920588776 -0700 +++ 25-akpm/fs/ext3/inode.c 2004-04-14 18:58:18.935586496 -0700 @@ -185,6 +185,8 @@ static int ext3_journal_test_restart(han */ void ext3_put_inode(struct inode *inode) { + if (!is_bad_inode(inode)) + ext3_discard_reservation(inode); } /* @@ -2052,6 +2054,8 @@ void ext3_truncate(struct inode * inode) if (IS_APPEND(inode) || IS_IMMUTABLE(inode)) return; + ext3_discard_reservation(inode); + /* * We have to lock the EOF page here, because lock_page() nests * outside journal_start(). @@ -2444,7 +2448,10 @@ void ext3_read_inode(struct inode * inod ei->i_disksize = inode->i_size; inode->i_generation = le32_to_cpu(raw_inode->i_generation); ei->i_block_group = iloc.block_group; - + ei->i_rsv_window.rsv_start = 0; + ei->i_rsv_window.rsv_end= 0; + ei->i_rsv_window.rsv_goal_size = EXT3_DEFAULT_RESERVE_BLOCKS; + INIT_LIST_HEAD(&ei->i_rsv_window.rsv_list); /* * NOTE! The in-memory inode i_data array is in little-endian order * even on big-endian machines: we do NOT byteswap the block numbers! diff -puN fs/ext3/super.c~ext3_rsv_base fs/ext3/super.c --- 25/fs/ext3/super.c~ext3_rsv_base 2004-04-14 18:58:18.921588624 -0700 +++ 25-akpm/fs/ext3/super.c 2004-04-14 18:58:18.937586192 -0700 @@ -1451,6 +1451,13 @@ static int ext3_fill_super (struct super sbi->s_gdb_count = db_count; get_random_bytes(&sbi->s_next_generation, sizeof(u32)); spin_lock_init(&sbi->s_next_gen_lock); + /* per fileystem reservation list head & lock */ + spin_lock_init(&sbi->s_rsv_window_lock); + INIT_LIST_HEAD(&sbi->s_rsv_window_head.rsv_list); + sbi->s_rsv_window_head.rsv_start = 0; + sbi->s_rsv_window_head.rsv_end = 0; + sbi->s_rsv_window_head.rsv_goal_size = 0; + /* * set up enough so that it can read an inode */ diff -puN include/linux/ext3_fs.h~ext3_rsv_base include/linux/ext3_fs.h --- 25/include/linux/ext3_fs.h~ext3_rsv_base 2004-04-14 18:58:18.923588320 -0700 +++ 25-akpm/include/linux/ext3_fs.h 2004-04-14 18:58:18.938586040 -0700 @@ -33,6 +33,11 @@ struct statfs; #undef EXT3FS_DEBUG /* + * Define EXT3_RESERVATION to reserve data blocks for expanding files + */ +#define EXT3_RESERVATION +#define EXT3_DEFAULT_RESERVE_BLOCKS 8 +/* * Always enable hashed directories */ #define CONFIG_EXT3_INDEX @@ -721,6 +726,7 @@ extern void ext3_put_inode (struct inode extern void ext3_delete_inode (struct inode *); extern int ext3_sync_inode (handle_t *, struct inode *); extern void ext3_discard_prealloc (struct inode *); +extern void ext3_discard_reservation (struct inode *); extern void ext3_dirty_inode(struct inode *); extern int ext3_change_inode_journal_flag(struct inode *, int); extern void ext3_truncate (struct inode *); diff -puN include/linux/ext3_fs_i.h~ext3_rsv_base include/linux/ext3_fs_i.h --- 25/include/linux/ext3_fs_i.h~ext3_rsv_base 2004-04-14 18:58:18.924588168 -0700 +++ 25-akpm/include/linux/ext3_fs_i.h 2004-04-14 18:58:18.939585888 -0700 @@ -18,8 +18,15 @@ #include +struct reserve_window { + struct list_head rsv_list; + __u32 rsv_start; + __u32 rsv_end; + unsigned short rsv_goal_size; +}; + /* - * second extended file system inode data in memory + * third extended file system inode data in memory */ struct ext3_inode_info { __u32 i_data[15]; @@ -57,6 +64,9 @@ struct ext3_inode_info { * allocation when we detect linearly ascending requests. */ __u32 i_next_alloc_goal; + /* block reservation window */ + struct reserve_window i_rsv_window; + __u32 i_dir_start_lookup; #ifdef CONFIG_EXT3_FS_XATTR /* diff -puN include/linux/ext3_fs_sb.h~ext3_rsv_base include/linux/ext3_fs_sb.h --- 25/include/linux/ext3_fs_sb.h~ext3_rsv_base 2004-04-14 18:58:18.925588016 -0700 +++ 25-akpm/include/linux/ext3_fs_sb.h 2004-04-14 18:58:18.939585888 -0700 @@ -59,6 +59,10 @@ struct ext3_sb_info { struct percpu_counter s_dirs_counter; struct blockgroup_lock s_blockgroup_lock; + /* head of the per fs reservation window tree */ + spinlock_t s_rsv_window_lock; + struct reserve_window s_rsv_window_head; + /* Journaling */ struct inode * s_journal_inode; struct journal_s * s_journal; _