[PATCH 2/4] ext3 block reservation patch set --ext3 block reservation

Mingming Cao
2004-04-14T00:51:28Z

[-- Attachment #1: Type: text/plain, Size: 629 bytes --]

> [patch 2]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

diffstat ext3_rsv_base.patch
fs/ext3/balloc.c | 548
++++++++++++++++++++++++++++++++++++++++-----
fs/ext3/file.c | 2
fs/ext3/ialloc.c | 5
fs/ext3/inode.c | 9
fs/ext3/super.c | 7
include/linux/ext3_fs.h | 6
include/linux/ext3_fs_i.h | 12
include/linux/ext3_fs_sb.h | 4
8 files changed, 542 insertions(+), 51 deletions(-)

[-- Attachment #2: ext3_rsv_base.patch --]
[-- Type: text/x-patch, Size: 27830 bytes --]

diff -urNp -X dontdiff 264-rsv-cleanup/fs/ext3/balloc.c 264-rsv-cleanup-base/fs/ext3/balloc.c
--- 264-rsv-cleanup/fs/ext3/balloc.c 2004-04-06 01:49:11.000000000 -0700
+++ 264-rsv-cleanup-base/fs/ext3/balloc.c 2004-04-13 01:42:40.352200376 -0700
@@ -96,6 +96,79 @@ 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 inline 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,
@@ -313,6 +386,33 @@ static inline int ext3_test_allocatable(
return ret;
}

+static inline 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 +425,6 @@ find_next_usable_block(int start, struct
{
int here, next;
char *p, *r;
- struct journal_head *jh = bh2jh(bh);

if (start > 0) {
/*
@@ -337,6 +436,8 @@ 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 +460,8 @@ 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 +497,421 @@ 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 cross 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);
}

+ if (start > EXT3_BLOCKS_PER_GROUP(sb)) BUG();
+
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
*/
- goal++;
- if (goal >= EXT3_BLOCKS_PER_GROUP(sb))
+ start++; goal++;
+ 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 reserable space big enough
+ * we could have a reservation cross
+ * 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 research, we could
+ * remember what's the largest reservable space we could have
+ * and return that on.
+ *
+ * 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 succeed, 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
+ * it's reservation window.
+ * each time when a new block allocation is need, first try to allocate
+ * from it's 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;
}

/*
@@ -489,6 +938,7 @@ 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 +989,8 @@ 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 +1018,8 @@ 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 -urNp -X dontdiff 264-rsv-cleanup/fs/ext3/file.c 264-rsv-cleanup-base/fs/ext3/file.c
--- 264-rsv-cleanup/fs/ext3/file.c 2004-04-06 01:49:11.000000000 -0700
+++ 264-rsv-cleanup-base/fs/ext3/file.c 2004-04-06 02:25:44.000000000 -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 -urNp -X dontdiff 264-rsv-cleanup/fs/ext3/ialloc.c 264-rsv-cleanup-base/fs/ext3/ialloc.c
--- 264-rsv-cleanup/fs/ext3/ialloc.c 2004-04-06 01:49:11.000000000 -0700
+++ 264-rsv-cleanup-base/fs/ext3/ialloc.c 2004-04-06 01:54:16.000000000 -0700
@@ -29,6 +29,7 @@
#include "xattr.h"
#include "acl.h"

+
/*
* ialloc.c contains the inodes allocation and deallocation routines
*/
@@ -581,6 +582,10 @@ 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 -urNp -X dontdiff 264-rsv-cleanup/fs/ext3/inode.c 264-rsv-cleanup-base/fs/ext3/inode.c
--- 264-rsv-cleanup/fs/ext3/inode.c 2004-04-06 01:49:11.000000000 -0700
+++ 264-rsv-cleanup-base/fs/ext3/inode.c 2004-04-06 01:56:16.000000000 -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);
}

/*
@@ -2053,6 +2055,8 @@ void ext3_truncate(struct inode * inode)
return;
if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
return;
+
+ ext3_discard_reservation(inode);

/*
* We have to lock the EOF page here, because lock_page() nests
@@ -2446,7 +2450,10 @@ 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 -urNp -X dontdiff 264-rsv-cleanup/fs/ext3/super.c 264-rsv-cleanup-base/fs/ext3/super.c
--- 264-rsv-cleanup/fs/ext3/super.c 2004-04-06 01:49:11.000000000 -0700
+++ 264-rsv-cleanup-base/fs/ext3/super.c 2004-04-06 01:50:03.000000000 -0700
@@ -1291,6 +1291,13 @@ 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 -urNp -X dontdiff 264-rsv-cleanup/include/linux/ext3_fs.h 264-rsv-cleanup-base/include/linux/ext3_fs.h
--- 264-rsv-cleanup/include/linux/ext3_fs.h 2004-04-06 01:49:13.000000000 -0700
+++ 264-rsv-cleanup-base/include/linux/ext3_fs.h 2004-04-06 01:59:01.000000000 -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 -urNp -X dontdiff 264-rsv-cleanup/include/linux/ext3_fs_i.h 264-rsv-cleanup-base/include/linux/ext3_fs_i.h
--- 264-rsv-cleanup/include/linux/ext3_fs_i.h 2004-04-06 01:49:13.000000000 -0700
+++ 264-rsv-cleanup-base/include/linux/ext3_fs_i.h 2004-04-06 02:00:35.000000000 -0700
@@ -18,8 +18,15 @@

#include <linux/rwsem.h>

+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 -urNp -X dontdiff 264-rsv-cleanup/include/linux/ext3_fs_sb.h 264-rsv-cleanup-base/include/linux/ext3_fs_sb.h
--- 264-rsv-cleanup/include/linux/ext3_fs_sb.h 2004-04-06 01:49:13.000000000 -0700
+++ 264-rsv-cleanup-base/include/linux/ext3_fs_sb.h 2004-04-06 01:50:04.000000000 -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;