Linux-2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
diff --git a/fs/reiserfs/bitmap.c b/fs/reiserfs/bitmap.c
new file mode 100644
index 0000000..a4e2ed5
--- /dev/null
+++ b/fs/reiserfs/bitmap.c
@@ -0,0 +1,1169 @@
+/*
+ * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
+ */
+/* Reiserfs block (de)allocator, bitmap-based. */
+
+#include <linux/config.h>
+#include <linux/time.h>
+#include <linux/reiserfs_fs.h>
+#include <linux/errno.h>
+#include <linux/buffer_head.h>
+#include <linux/kernel.h>
+#include <linux/pagemap.h>
+#include <linux/reiserfs_fs_sb.h>
+#include <linux/reiserfs_fs_i.h>
+#include <linux/quotaops.h>
+
+#define PREALLOCATION_SIZE 9
+
+/* different reiserfs block allocator options */
+
+#define SB_ALLOC_OPTS(s) (REISERFS_SB(s)->s_alloc_options.bits)
+
+#define _ALLOC_concentrating_formatted_nodes 0
+#define _ALLOC_displacing_large_files 1
+#define _ALLOC_displacing_new_packing_localities 2
+#define _ALLOC_old_hashed_relocation 3
+#define _ALLOC_new_hashed_relocation 4
+#define _ALLOC_skip_busy 5
+#define _ALLOC_displace_based_on_dirid 6
+#define _ALLOC_hashed_formatted_nodes 7
+#define _ALLOC_old_way 8
+#define _ALLOC_hundredth_slices 9
+#define _ALLOC_dirid_groups 10
+#define _ALLOC_oid_groups 11
+#define _ALLOC_packing_groups 12
+
+#define concentrating_formatted_nodes(s) test_bit(_ALLOC_concentrating_formatted_nodes, &SB_ALLOC_OPTS(s))
+#define displacing_large_files(s) test_bit(_ALLOC_displacing_large_files, &SB_ALLOC_OPTS(s))
+#define displacing_new_packing_localities(s) test_bit(_ALLOC_displacing_new_packing_localities, &SB_ALLOC_OPTS(s))
+
+#define SET_OPTION(optname) \
+ do { \
+ reiserfs_warning(s, "reiserfs: option \"%s\" is set", #optname); \
+ set_bit(_ALLOC_ ## optname , &SB_ALLOC_OPTS(s)); \
+ } while(0)
+#define TEST_OPTION(optname, s) \
+ test_bit(_ALLOC_ ## optname , &SB_ALLOC_OPTS(s))
+
+static inline void get_bit_address (struct super_block * s,
+ b_blocknr_t block, int * bmap_nr, int * offset)
+{
+ /* It is in the bitmap block number equal to the block
+ * number divided by the number of bits in a block. */
+ *bmap_nr = block / (s->s_blocksize << 3);
+ /* Within that bitmap block it is located at bit offset *offset. */
+ *offset = block & ((s->s_blocksize << 3) - 1 );
+ return;
+}
+
+#ifdef CONFIG_REISERFS_CHECK
+int is_reusable (struct super_block * s, b_blocknr_t block, int bit_value)
+{
+ int i, j;
+
+ if (block == 0 || block >= SB_BLOCK_COUNT (s)) {
+ reiserfs_warning (s, "vs-4010: is_reusable: block number is out of range %lu (%u)",
+ block, SB_BLOCK_COUNT (s));
+ return 0;
+ }
+
+ /* it can't be one of the bitmap blocks */
+ for (i = 0; i < SB_BMAP_NR (s); i ++)
+ if (block == SB_AP_BITMAP (s)[i].bh->b_blocknr) {
+ reiserfs_warning (s, "vs: 4020: is_reusable: "
+ "bitmap block %lu(%u) can't be freed or reused",
+ block, SB_BMAP_NR (s));
+ return 0;
+ }
+
+ get_bit_address (s, block, &i, &j);
+
+ if (i >= SB_BMAP_NR (s)) {
+ reiserfs_warning (s, "vs-4030: is_reusable: there is no so many bitmap blocks: "
+ "block=%lu, bitmap_nr=%d", block, i);
+ return 0;
+ }
+
+ if ((bit_value == 0 &&
+ reiserfs_test_le_bit(j, SB_AP_BITMAP(s)[i].bh->b_data)) ||
+ (bit_value == 1 &&
+ reiserfs_test_le_bit(j, SB_AP_BITMAP (s)[i].bh->b_data) == 0)) {
+ reiserfs_warning (s, "vs-4040: is_reusable: corresponding bit of block %lu does not "
+ "match required value (i==%d, j==%d) test_bit==%d",
+ block, i, j, reiserfs_test_le_bit (j, SB_AP_BITMAP (s)[i].bh->b_data));
+
+ return 0;
+ }
+
+ if (bit_value == 0 && block == SB_ROOT_BLOCK (s)) {
+ reiserfs_warning (s, "vs-4050: is_reusable: this is root block (%u), "
+ "it must be busy", SB_ROOT_BLOCK (s));
+ return 0;
+ }
+
+ return 1;
+}
+#endif /* CONFIG_REISERFS_CHECK */
+
+/* searches in journal structures for a given block number (bmap, off). If block
+ is found in reiserfs journal it suggests next free block candidate to test. */
+static inline int is_block_in_journal (struct super_block * s, int bmap, int
+off, int *next)
+{
+ b_blocknr_t tmp;
+
+ if (reiserfs_in_journal (s, bmap, off, 1, &tmp)) {
+ if (tmp) { /* hint supplied */
+ *next = tmp;
+ PROC_INFO_INC( s, scan_bitmap.in_journal_hint );
+ } else {
+ (*next) = off + 1; /* inc offset to avoid looping. */
+ PROC_INFO_INC( s, scan_bitmap.in_journal_nohint );
+ }
+ PROC_INFO_INC( s, scan_bitmap.retry );
+ return 1;
+ }
+ return 0;
+}
+
+/* it searches for a window of zero bits with given minimum and maximum lengths in one bitmap
+ * block; */
+static int scan_bitmap_block (struct reiserfs_transaction_handle *th,
+ int bmap_n, int *beg, int boundary, int min, int max, int unfm)
+{
+ struct super_block *s = th->t_super;
+ struct reiserfs_bitmap_info *bi=&SB_AP_BITMAP(s)[bmap_n];
+ int end, next;
+ int org = *beg;
+
+ BUG_ON (!th->t_trans_id);
+
+ RFALSE(bmap_n >= SB_BMAP_NR (s), "Bitmap %d is out of range (0..%d)",bmap_n, SB_BMAP_NR (s) - 1);
+ PROC_INFO_INC( s, scan_bitmap.bmap );
+/* this is unclear and lacks comments, explain how journal bitmaps
+ work here for the reader. Convey a sense of the design here. What
+ is a window? */
+/* - I mean `a window of zero bits' as in description of this function - Zam. */
+
+ if ( !bi ) {
+ reiserfs_warning (s, "NULL bitmap info pointer for bitmap %d", bmap_n);
+ return 0;
+ }
+ if (buffer_locked (bi->bh)) {
+ PROC_INFO_INC( s, scan_bitmap.wait );
+ __wait_on_buffer (bi->bh);
+ }
+
+ while (1) {
+ cont:
+ if (bi->free_count < min)
+ return 0; // No free blocks in this bitmap
+
+ /* search for a first zero bit -- beggining of a window */
+ *beg = reiserfs_find_next_zero_le_bit
+ ((unsigned long*)(bi->bh->b_data), boundary, *beg);
+
+ if (*beg + min > boundary) { /* search for a zero bit fails or the rest of bitmap block
+ * cannot contain a zero window of minimum size */
+ return 0;
+ }
+
+ if (unfm && is_block_in_journal(s,bmap_n, *beg, beg))
+ continue;
+ /* first zero bit found; we check next bits */
+ for (end = *beg + 1;; end ++) {
+ if (end >= *beg + max || end >= boundary || reiserfs_test_le_bit (end, bi->bh->b_data)) {
+ next = end;
+ break;
+ }
+ /* finding the other end of zero bit window requires looking into journal structures (in
+ * case of searching for free blocks for unformatted nodes) */
+ if (unfm && is_block_in_journal(s, bmap_n, end, &next))
+ break;
+ }
+
+ /* now (*beg) points to beginning of zero bits window,
+ * (end) points to one bit after the window end */
+ if (end - *beg >= min) { /* it seems we have found window of proper size */
+ int i;
+ reiserfs_prepare_for_journal (s, bi->bh, 1);
+ /* try to set all blocks used checking are they still free */
+ for (i = *beg; i < end; i++) {
+ /* It seems that we should not check in journal again. */
+ if (reiserfs_test_and_set_le_bit (i, bi->bh->b_data)) {
+ /* bit was set by another process
+ * while we slept in prepare_for_journal() */
+ PROC_INFO_INC( s, scan_bitmap.stolen );
+ if (i >= *beg + min) { /* we can continue with smaller set of allocated blocks,
+ * if length of this set is more or equal to `min' */
+ end = i;
+ break;
+ }
+ /* otherwise we clear all bit were set ... */
+ while (--i >= *beg)
+ reiserfs_test_and_clear_le_bit (i, bi->bh->b_data);
+ reiserfs_restore_prepared_buffer (s, bi->bh);
+ *beg = org;
+ /* ... and search again in current block from beginning */
+ goto cont;
+ }
+ }
+ bi->free_count -= (end - *beg);
+ journal_mark_dirty (th, s, bi->bh);
+
+ /* free block count calculation */
+ reiserfs_prepare_for_journal (s, SB_BUFFER_WITH_SB(s), 1);
+ PUT_SB_FREE_BLOCKS(s, SB_FREE_BLOCKS(s) - (end - *beg));
+ journal_mark_dirty (th, s, SB_BUFFER_WITH_SB(s));
+
+ return end - (*beg);
+ } else {
+ *beg = next;
+ }
+ }
+}
+
+static int bmap_hash_id(struct super_block *s, u32 id) {
+ char * hash_in = NULL;
+ unsigned long hash;
+ unsigned bm;
+
+ if (id <= 2) {
+ bm = 1;
+ } else {
+ hash_in = (char *)(&id);
+ hash = keyed_hash(hash_in, 4);
+ bm = hash % SB_BMAP_NR(s);
+ if (!bm)
+ bm = 1;
+ }
+ /* this can only be true when SB_BMAP_NR = 1 */
+ if (bm >= SB_BMAP_NR(s))
+ bm = 0;
+ return bm;
+}
+
+/*
+ * hashes the id and then returns > 0 if the block group for the
+ * corresponding hash is full
+ */
+static inline int block_group_used(struct super_block *s, u32 id) {
+ int bm;
+ bm = bmap_hash_id(s, id);
+ if (SB_AP_BITMAP(s)[bm].free_count > ((s->s_blocksize << 3) * 60 / 100) ) {
+ return 0;
+ }
+ return 1;
+}
+
+/*
+ * the packing is returned in disk byte order
+ */
+u32 reiserfs_choose_packing(struct inode *dir) {
+ u32 packing;
+ if (TEST_OPTION(packing_groups, dir->i_sb)) {
+ u32 parent_dir = le32_to_cpu(INODE_PKEY(dir)->k_dir_id);
+ /*
+ * some versions of reiserfsck expect packing locality 1 to be
+ * special
+ */
+ if (parent_dir == 1 || block_group_used(dir->i_sb,parent_dir))
+ packing = INODE_PKEY(dir)->k_objectid;
+ else
+ packing = INODE_PKEY(dir)->k_dir_id;
+ } else
+ packing = INODE_PKEY(dir)->k_objectid;
+ return packing;
+}
+
+/* Tries to find contiguous zero bit window (given size) in given region of
+ * bitmap and place new blocks there. Returns number of allocated blocks. */
+static int scan_bitmap (struct reiserfs_transaction_handle *th,
+ b_blocknr_t *start, b_blocknr_t finish,
+ int min, int max, int unfm, unsigned long file_block)
+{
+ int nr_allocated=0;
+ struct super_block * s = th->t_super;
+ /* find every bm and bmap and bmap_nr in this file, and change them all to bitmap_blocknr
+ * - Hans, it is not a block number - Zam. */
+
+ int bm, off;
+ int end_bm, end_off;
+ int off_max = s->s_blocksize << 3;
+
+ BUG_ON (!th->t_trans_id);
+
+ PROC_INFO_INC( s, scan_bitmap.call );
+ if ( SB_FREE_BLOCKS(s) <= 0)
+ return 0; // No point in looking for more free blocks
+
+ get_bit_address (s, *start, &bm, &off);
+ get_bit_address (s, finish, &end_bm, &end_off);
+ if (bm > SB_BMAP_NR(s))
+ return 0;
+ if (end_bm > SB_BMAP_NR(s))
+ end_bm = SB_BMAP_NR(s);
+
+ /* When the bitmap is more than 10% free, anyone can allocate.
+ * When it's less than 10% free, only files that already use the
+ * bitmap are allowed. Once we pass 80% full, this restriction
+ * is lifted.
+ *
+ * We do this so that files that grow later still have space close to
+ * their original allocation. This improves locality, and presumably
+ * performance as a result.
+ *
+ * This is only an allocation policy and does not make up for getting a
+ * bad hint. Decent hinting must be implemented for this to work well.
+ */
+ if ( TEST_OPTION(skip_busy, s) && SB_FREE_BLOCKS(s) > SB_BLOCK_COUNT(s)/20 ) {
+ for (;bm < end_bm; bm++, off = 0) {
+ if ( ( off && (!unfm || (file_block != 0))) || SB_AP_BITMAP(s)[bm].free_count > (s->s_blocksize << 3) / 10 )
+ nr_allocated = scan_bitmap_block(th, bm, &off, off_max, min, max, unfm);
+ if (nr_allocated)
+ goto ret;
+ }
+ /* we know from above that start is a reasonable number */
+ get_bit_address (s, *start, &bm, &off);
+ }
+
+ for (;bm < end_bm; bm++, off = 0) {
+ nr_allocated = scan_bitmap_block(th, bm, &off, off_max, min, max, unfm);
+ if (nr_allocated)
+ goto ret;
+ }
+
+ nr_allocated = scan_bitmap_block(th, bm, &off, end_off + 1, min, max, unfm);
+
+ ret:
+ *start = bm * off_max + off;
+ return nr_allocated;
+
+}
+
+static void _reiserfs_free_block (struct reiserfs_transaction_handle *th,
+ struct inode *inode, b_blocknr_t block,
+ int for_unformatted)
+{
+ struct super_block * s = th->t_super;
+ struct reiserfs_super_block * rs;
+ struct buffer_head * sbh;
+ struct reiserfs_bitmap_info *apbi;
+ int nr, offset;
+
+ BUG_ON (!th->t_trans_id);
+
+ PROC_INFO_INC( s, free_block );
+
+ rs = SB_DISK_SUPER_BLOCK (s);
+ sbh = SB_BUFFER_WITH_SB (s);
+ apbi = SB_AP_BITMAP(s);
+
+ get_bit_address (s, block, &nr, &offset);
+
+ if (nr >= sb_bmap_nr (rs)) {
+ reiserfs_warning (s, "vs-4075: reiserfs_free_block: "
+ "block %lu is out of range on %s",
+ block, reiserfs_bdevname (s));
+ return;
+ }
+
+ reiserfs_prepare_for_journal(s, apbi[nr].bh, 1 ) ;
+
+ /* clear bit for the given block in bit map */
+ if (!reiserfs_test_and_clear_le_bit (offset, apbi[nr].bh->b_data)) {
+ reiserfs_warning (s, "vs-4080: reiserfs_free_block: "
+ "free_block (%s:%lu)[dev:blocknr]: bit already cleared",
+ reiserfs_bdevname (s), block);
+ }
+ apbi[nr].free_count ++;
+ journal_mark_dirty (th, s, apbi[nr].bh);
+
+ reiserfs_prepare_for_journal(s, sbh, 1) ;
+ /* update super block */
+ set_sb_free_blocks( rs, sb_free_blocks(rs) + 1 );
+
+ journal_mark_dirty (th, s, sbh);
+ if (for_unformatted)
+ DQUOT_FREE_BLOCK_NODIRTY(inode, 1);
+}
+
+void reiserfs_free_block (struct reiserfs_transaction_handle *th,
+ struct inode *inode, b_blocknr_t block,
+ int for_unformatted)
+{
+ struct super_block * s = th->t_super;
+
+ BUG_ON (!th->t_trans_id);
+
+ RFALSE(!s, "vs-4061: trying to free block on nonexistent device");
+ RFALSE(is_reusable (s, block, 1) == 0, "vs-4071: can not free such block");
+ /* mark it before we clear it, just in case */
+ journal_mark_freed(th, s, block) ;
+ _reiserfs_free_block(th, inode, block, for_unformatted) ;
+}
+
+/* preallocated blocks don't need to be run through journal_mark_freed */
+static void reiserfs_free_prealloc_block (struct reiserfs_transaction_handle *th,
+ struct inode *inode, b_blocknr_t block) {
+ RFALSE(!th->t_super, "vs-4060: trying to free block on nonexistent device");
+ RFALSE(is_reusable (th->t_super, block, 1) == 0, "vs-4070: can not free such block");
+ BUG_ON (!th->t_trans_id);
+ _reiserfs_free_block(th, inode, block, 1) ;
+}
+
+static void __discard_prealloc (struct reiserfs_transaction_handle * th,
+ struct reiserfs_inode_info *ei)
+{
+ unsigned long save = ei->i_prealloc_block ;
+ int dirty = 0;
+ struct inode *inode = &ei->vfs_inode;
+ BUG_ON (!th->t_trans_id);
+#ifdef CONFIG_REISERFS_CHECK
+ if (ei->i_prealloc_count < 0)
+ reiserfs_warning (th->t_super, "zam-4001:%s: inode has negative prealloc blocks count.", __FUNCTION__ );
+#endif
+ while (ei->i_prealloc_count > 0) {
+ reiserfs_free_prealloc_block(th, inode, ei->i_prealloc_block);
+ ei->i_prealloc_block++;
+ ei->i_prealloc_count --;
+ dirty = 1;
+ }
+ if (dirty)
+ reiserfs_update_sd(th, inode);
+ ei->i_prealloc_block = save;
+ list_del_init(&(ei->i_prealloc_list));
+}
+
+/* FIXME: It should be inline function */
+void reiserfs_discard_prealloc (struct reiserfs_transaction_handle *th,
+ struct inode *inode)
+{
+ struct reiserfs_inode_info *ei = REISERFS_I(inode);
+ BUG_ON (!th->t_trans_id);
+ if (ei->i_prealloc_count)
+ __discard_prealloc(th, ei);
+}
+
+void reiserfs_discard_all_prealloc (struct reiserfs_transaction_handle *th)
+{
+ struct list_head * plist = &SB_JOURNAL(th->t_super)->j_prealloc_list;
+
+ BUG_ON (!th->t_trans_id);
+
+ while (!list_empty(plist)) {
+ struct reiserfs_inode_info *ei;
+ ei = list_entry(plist->next, struct reiserfs_inode_info, i_prealloc_list);
+#ifdef CONFIG_REISERFS_CHECK
+ if (!ei->i_prealloc_count) {
+ reiserfs_warning (th->t_super, "zam-4001:%s: inode is in prealloc list but has no preallocated blocks.", __FUNCTION__);
+ }
+#endif
+ __discard_prealloc(th, ei);
+ }
+}
+
+void reiserfs_init_alloc_options (struct super_block *s)
+{
+ set_bit (_ALLOC_skip_busy, &SB_ALLOC_OPTS(s));
+ set_bit (_ALLOC_dirid_groups, &SB_ALLOC_OPTS(s));
+ set_bit (_ALLOC_packing_groups, &SB_ALLOC_OPTS(s));
+}
+
+/* block allocator related options are parsed here */
+int reiserfs_parse_alloc_options(struct super_block * s, char * options)
+{
+ char * this_char, * value;
+
+ REISERFS_SB(s)->s_alloc_options.bits = 0; /* clear default settings */
+
+ while ( (this_char = strsep (&options, ":")) != NULL ) {
+ if ((value = strchr (this_char, '=')) != NULL)
+ *value++ = 0;
+
+ if (!strcmp(this_char, "concentrating_formatted_nodes")) {
+ int temp;
+ SET_OPTION(concentrating_formatted_nodes);
+ temp = (value && *value) ? simple_strtoul (value, &value, 0) : 10;
+ if (temp <= 0 || temp > 100) {
+ REISERFS_SB(s)->s_alloc_options.border = 10;
+ } else {
+ REISERFS_SB(s)->s_alloc_options.border = 100 / temp;
+ }
+ continue;
+ }
+ if (!strcmp(this_char, "displacing_large_files")) {
+ SET_OPTION(displacing_large_files);
+ REISERFS_SB(s)->s_alloc_options.large_file_size =
+ (value && *value) ? simple_strtoul (value, &value, 0) : 16;
+ continue;
+ }
+ if (!strcmp(this_char, "displacing_new_packing_localities")) {
+ SET_OPTION(displacing_new_packing_localities);
+ continue;
+ };
+
+ if (!strcmp(this_char, "old_hashed_relocation")) {
+ SET_OPTION(old_hashed_relocation);
+ continue;
+ }
+
+ if (!strcmp(this_char, "new_hashed_relocation")) {
+ SET_OPTION(new_hashed_relocation);
+ continue;
+ }
+
+ if (!strcmp(this_char, "dirid_groups")) {
+ SET_OPTION(dirid_groups);
+ continue;
+ }
+ if (!strcmp(this_char, "oid_groups")) {
+ SET_OPTION(oid_groups);
+ continue;
+ }
+ if (!strcmp(this_char, "packing_groups")) {
+ SET_OPTION(packing_groups);
+ continue;
+ }
+ if (!strcmp(this_char, "hashed_formatted_nodes")) {
+ SET_OPTION(hashed_formatted_nodes);
+ continue;
+ }
+
+ if (!strcmp(this_char, "skip_busy")) {
+ SET_OPTION(skip_busy);
+ continue;
+ }
+
+ if (!strcmp(this_char, "hundredth_slices")) {
+ SET_OPTION(hundredth_slices);
+ continue;
+ }
+
+ if (!strcmp(this_char, "old_way")) {
+ SET_OPTION(old_way);
+ continue;
+ }
+
+ if (!strcmp(this_char, "displace_based_on_dirid")) {
+ SET_OPTION(displace_based_on_dirid);
+ continue;
+ }
+
+ if (!strcmp(this_char, "preallocmin")) {
+ REISERFS_SB(s)->s_alloc_options.preallocmin =
+ (value && *value) ? simple_strtoul (value, &value, 0) : 4;
+ continue;
+ }
+
+ if (!strcmp(this_char, "preallocsize")) {
+ REISERFS_SB(s)->s_alloc_options.preallocsize =
+ (value && *value) ? simple_strtoul (value, &value, 0) : PREALLOCATION_SIZE;
+ continue;
+ }
+
+ reiserfs_warning (s, "zam-4001: %s : unknown option - %s",
+ __FUNCTION__ , this_char);
+ return 1;
+ }
+
+ reiserfs_warning (s, "allocator options = [%08x]\n", SB_ALLOC_OPTS(s));
+ return 0;
+}
+
+static inline void new_hashed_relocation (reiserfs_blocknr_hint_t * hint)
+{
+ char * hash_in;
+ if (hint->formatted_node) {
+ hash_in = (char*)&hint->key.k_dir_id;
+ } else {
+ if (!hint->inode) {
+ //hint->search_start = hint->beg;
+ hash_in = (char*)&hint->key.k_dir_id;
+ } else
+ if ( TEST_OPTION(displace_based_on_dirid, hint->th->t_super))
+ hash_in = (char *)(&INODE_PKEY(hint->inode)->k_dir_id);
+ else
+ hash_in = (char *)(&INODE_PKEY(hint->inode)->k_objectid);
+ }
+
+ hint->search_start = hint->beg + keyed_hash(hash_in, 4) % (hint->end - hint->beg);
+}
+
+/*
+ * Relocation based on dirid, hashing them into a given bitmap block
+ * files. Formatted nodes are unaffected, a seperate policy covers them
+ */
+static void
+dirid_groups (reiserfs_blocknr_hint_t *hint)
+{
+ unsigned long hash;
+ __u32 dirid = 0;
+ int bm = 0;
+ struct super_block *sb = hint->th->t_super;
+ if (hint->inode)
+ dirid = le32_to_cpu(INODE_PKEY(hint->inode)->k_dir_id);
+ else if (hint->formatted_node)
+ dirid = hint->key.k_dir_id;
+
+ if (dirid) {
+ bm = bmap_hash_id(sb, dirid);
+ hash = bm * (sb->s_blocksize << 3);
+ /* give a portion of the block group to metadata */
+ if (hint->inode)
+ hash += sb->s_blocksize/2;
+ hint->search_start = hash;
+ }
+}
+
+/*
+ * Relocation based on oid, hashing them into a given bitmap block
+ * files. Formatted nodes are unaffected, a seperate policy covers them
+ */
+static void
+oid_groups (reiserfs_blocknr_hint_t *hint)
+{
+ if (hint->inode) {
+ unsigned long hash;
+ __u32 oid;
+ __u32 dirid;
+ int bm;
+
+ dirid = le32_to_cpu(INODE_PKEY(hint->inode)->k_dir_id);
+
+ /* keep the root dir and it's first set of subdirs close to
+ * the start of the disk
+ */
+ if (dirid <= 2)
+ hash = (hint->inode->i_sb->s_blocksize << 3);
+ else {
+ oid = le32_to_cpu(INODE_PKEY(hint->inode)->k_objectid);
+ bm = bmap_hash_id(hint->inode->i_sb, oid);
+ hash = bm * (hint->inode->i_sb->s_blocksize << 3);
+ }
+ hint->search_start = hash;
+ }
+}
+
+/* returns 1 if it finds an indirect item and gets valid hint info
+ * from it, otherwise 0
+ */
+static int get_left_neighbor(reiserfs_blocknr_hint_t *hint)
+{
+ struct path * path;
+ struct buffer_head * bh;
+ struct item_head * ih;
+ int pos_in_item;
+ __u32 * item;
+ int ret = 0;
+
+ if (!hint->path) /* reiserfs code can call this function w/o pointer to path
+ * structure supplied; then we rely on supplied search_start */
+ return 0;
+
+ path = hint->path;
+ bh = get_last_bh(path);
+ RFALSE( !bh, "green-4002: Illegal path specified to get_left_neighbor");
+ ih = get_ih(path);
+ pos_in_item = path->pos_in_item;
+ item = get_item (path);
+
+ hint->search_start = bh->b_blocknr;
+
+ if (!hint->formatted_node && is_indirect_le_ih (ih)) {
+ /* for indirect item: go to left and look for the first non-hole entry
+ in the indirect item */
+ if (pos_in_item == I_UNFM_NUM (ih))
+ pos_in_item--;
+// pos_in_item = I_UNFM_NUM (ih) - 1;
+ while (pos_in_item >= 0) {
+ int t=get_block_num(item,pos_in_item);
+ if (t) {
+ hint->search_start = t;
+ ret = 1;
+ break;
+ }
+ pos_in_item --;
+ }
+ }
+
+ /* does result value fit into specified region? */
+ return ret;
+}
+
+/* should be, if formatted node, then try to put on first part of the device
+ specified as number of percent with mount option device, else try to put
+ on last of device. This is not to say it is good code to do so,
+ but the effect should be measured. */
+static inline void set_border_in_hint(struct super_block *s, reiserfs_blocknr_hint_t *hint)
+{
+ b_blocknr_t border = SB_BLOCK_COUNT(s) / REISERFS_SB(s)->s_alloc_options.border;
+
+ if (hint->formatted_node)
+ hint->end = border - 1;
+ else
+ hint->beg = border;
+}
+
+static inline void displace_large_file(reiserfs_blocknr_hint_t *hint)
+{
+ if ( TEST_OPTION(displace_based_on_dirid, hint->th->t_super))
+ hint->search_start = hint->beg + keyed_hash((char *)(&INODE_PKEY(hint->inode)->k_dir_id), 4) % (hint->end - hint->beg);
+ else
+ hint->search_start = hint->beg + keyed_hash((char *)(&INODE_PKEY(hint->inode)->k_objectid), 4) % (hint->end - hint->beg);
+}
+
+static inline void hash_formatted_node(reiserfs_blocknr_hint_t *hint)
+{
+ char * hash_in;
+
+ if (!hint->inode)
+ hash_in = (char*)&hint->key.k_dir_id;
+ else if ( TEST_OPTION(displace_based_on_dirid, hint->th->t_super))
+ hash_in = (char *)(&INODE_PKEY(hint->inode)->k_dir_id);
+ else
+ hash_in = (char *)(&INODE_PKEY(hint->inode)->k_objectid);
+
+ hint->search_start = hint->beg + keyed_hash(hash_in, 4) % (hint->end - hint->beg);
+}
+
+static inline int this_blocknr_allocation_would_make_it_a_large_file(reiserfs_blocknr_hint_t *hint)
+{
+ return hint->block == REISERFS_SB(hint->th->t_super)->s_alloc_options.large_file_size;
+}
+
+#ifdef DISPLACE_NEW_PACKING_LOCALITIES
+static inline void displace_new_packing_locality (reiserfs_blocknr_hint_t *hint)
+{
+ struct reiserfs_key * key = &hint->key;
+
+ hint->th->displace_new_blocks = 0;
+ hint->search_start = hint->beg + keyed_hash((char*)(&key->k_objectid),4) % (hint->end - hint->beg);
+}
+ #endif
+
+static inline int old_hashed_relocation (reiserfs_blocknr_hint_t * hint)
+{
+ b_blocknr_t border;
+ u32 hash_in;
+
+ if (hint->formatted_node || hint->inode == NULL) {
+ return 0;
+ }
+
+ hash_in = le32_to_cpu((INODE_PKEY(hint->inode))->k_dir_id);
+ border = hint->beg + (u32) keyed_hash(((char *) (&hash_in)), 4) % (hint->end - hint->beg - 1);
+ if (border > hint->search_start)
+ hint->search_start = border;
+
+ return 1;
+ }
+
+static inline int old_way (reiserfs_blocknr_hint_t * hint)
+{
+ b_blocknr_t border;
+
+ if (hint->formatted_node || hint->inode == NULL) {
+ return 0;
+ }
+
+ border = hint->beg + le32_to_cpu(INODE_PKEY(hint->inode)->k_dir_id) % (hint->end - hint->beg);
+ if (border > hint->search_start)
+ hint->search_start = border;
+
+ return 1;
+}
+
+static inline void hundredth_slices (reiserfs_blocknr_hint_t * hint)
+{
+ struct reiserfs_key * key = &hint->key;
+ b_blocknr_t slice_start;
+
+ slice_start = (keyed_hash((char*)(&key->k_dir_id),4) % 100) * (hint->end / 100);
+ if ( slice_start > hint->search_start || slice_start + (hint->end / 100) <= hint->search_start) {
+ hint->search_start = slice_start;
+ }
+}
+
+static void determine_search_start(reiserfs_blocknr_hint_t *hint,
+ int amount_needed)
+{
+ struct super_block *s = hint->th->t_super;
+ int unfm_hint;
+
+ hint->beg = 0;
+ hint->end = SB_BLOCK_COUNT(s) - 1;
+
+ /* This is former border algorithm. Now with tunable border offset */
+ if (concentrating_formatted_nodes(s))
+ set_border_in_hint(s, hint);
+
+#ifdef DISPLACE_NEW_PACKING_LOCALITIES
+ /* whenever we create a new directory, we displace it. At first we will
+ hash for location, later we might look for a moderately empty place for
+ it */
+ if (displacing_new_packing_localities(s)
+ && hint->th->displace_new_blocks) {
+ displace_new_packing_locality(hint);
+
+ /* we do not continue determine_search_start,
+ * if new packing locality is being displaced */
+ return;
+ }
+#endif
+
+ /* all persons should feel encouraged to add more special cases here and
+ * test them */
+
+ if (displacing_large_files(s) && !hint->formatted_node
+ && this_blocknr_allocation_would_make_it_a_large_file(hint)) {
+ displace_large_file(hint);
+ return;
+ }
+
+ /* if none of our special cases is relevant, use the left neighbor in the
+ tree order of the new node we are allocating for */
+ if (hint->formatted_node && TEST_OPTION(hashed_formatted_nodes,s)) {
+ hash_formatted_node(hint);
+ return;
+ }
+
+ unfm_hint = get_left_neighbor(hint);
+
+ /* Mimic old block allocator behaviour, that is if VFS allowed for preallocation,
+ new blocks are displaced based on directory ID. Also, if suggested search_start
+ is less than last preallocated block, we start searching from it, assuming that
+ HDD dataflow is faster in forward direction */
+ if ( TEST_OPTION(old_way, s)) {
+ if (!hint->formatted_node) {
+ if ( !reiserfs_hashed_relocation(s))
+ old_way(hint);
+ else if (!reiserfs_no_unhashed_relocation(s))
+ old_hashed_relocation(hint);
+
+ if ( hint->inode && hint->search_start < REISERFS_I(hint->inode)->i_prealloc_block)
+ hint->search_start = REISERFS_I(hint->inode)->i_prealloc_block;
+ }
+ return;
+ }
+
+ /* This is an approach proposed by Hans */
+ if ( TEST_OPTION(hundredth_slices, s) && ! (displacing_large_files(s) && !hint->formatted_node)) {
+ hundredth_slices(hint);
+ return;
+ }
+
+ /* old_hashed_relocation only works on unformatted */
+ if (!unfm_hint && !hint->formatted_node &&
+ TEST_OPTION(old_hashed_relocation, s))
+ {
+ old_hashed_relocation(hint);
+ }
+ /* new_hashed_relocation works with both formatted/unformatted nodes */
+ if ((!unfm_hint || hint->formatted_node) &&
+ TEST_OPTION(new_hashed_relocation, s))
+ {
+ new_hashed_relocation(hint);
+ }
+ /* dirid grouping works only on unformatted nodes */
+ if (!unfm_hint && !hint->formatted_node && TEST_OPTION(dirid_groups,s))
+ {
+ dirid_groups(hint);
+ }
+
+#ifdef DISPLACE_NEW_PACKING_LOCALITIES
+ if (hint->formatted_node && TEST_OPTION(dirid_groups,s))
+ {
+ dirid_groups(hint);
+ }
+#endif
+
+ /* oid grouping works only on unformatted nodes */
+ if (!unfm_hint && !hint->formatted_node && TEST_OPTION(oid_groups,s))
+ {
+ oid_groups(hint);
+ }
+ return;
+}
+
+static int determine_prealloc_size(reiserfs_blocknr_hint_t * hint)
+{
+ /* make minimum size a mount option and benchmark both ways */
+ /* we preallocate blocks only for regular files, specific size */
+ /* benchmark preallocating always and see what happens */
+
+ hint->prealloc_size = 0;
+
+ if (!hint->formatted_node && hint->preallocate) {
+ if (S_ISREG(hint->inode->i_mode)
+ && hint->inode->i_size >= REISERFS_SB(hint->th->t_super)->s_alloc_options.preallocmin * hint->inode->i_sb->s_blocksize)
+ hint->prealloc_size = REISERFS_SB(hint->th->t_super)->s_alloc_options.preallocsize - 1;
+ }
+ return CARRY_ON;
+}
+
+/* XXX I know it could be merged with upper-level function;
+ but may be result function would be too complex. */
+static inline int allocate_without_wrapping_disk (reiserfs_blocknr_hint_t * hint,
+ b_blocknr_t * new_blocknrs,
+ b_blocknr_t start, b_blocknr_t finish,
+ int min,
+ int amount_needed, int prealloc_size)
+{
+ int rest = amount_needed;
+ int nr_allocated;
+
+ while (rest > 0 && start <= finish) {
+ nr_allocated = scan_bitmap (hint->th, &start, finish, min,
+ rest + prealloc_size, !hint->formatted_node,
+ hint->block);
+
+ if (nr_allocated == 0) /* no new blocks allocated, return */
+ break;
+
+ /* fill free_blocknrs array first */
+ while (rest > 0 && nr_allocated > 0) {
+ * new_blocknrs ++ = start ++;
+ rest --; nr_allocated --;
+ }
+
+ /* do we have something to fill prealloc. array also ? */
+ if (nr_allocated > 0) {
+ /* it means prealloc_size was greater that 0 and we do preallocation */
+ list_add(&REISERFS_I(hint->inode)->i_prealloc_list,
+ &SB_JOURNAL(hint->th->t_super)->j_prealloc_list);
+ REISERFS_I(hint->inode)->i_prealloc_block = start;
+ REISERFS_I(hint->inode)->i_prealloc_count = nr_allocated;
+ break;
+ }
+ }
+
+ return (amount_needed - rest);
+}
+
+static inline int blocknrs_and_prealloc_arrays_from_search_start
+ (reiserfs_blocknr_hint_t *hint, b_blocknr_t *new_blocknrs, int amount_needed)
+{
+ struct super_block *s = hint->th->t_super;
+ b_blocknr_t start = hint->search_start;
+ b_blocknr_t finish = SB_BLOCK_COUNT(s) - 1;
+ int passno = 0;
+ int nr_allocated = 0;
+ int bigalloc = 0;
+
+ determine_prealloc_size(hint);
+ if (!hint->formatted_node) {
+ int quota_ret;
+#ifdef REISERQUOTA_DEBUG
+ reiserfs_debug (s, REISERFS_DEBUG_CODE, "reiserquota: allocating %d blocks id=%u", amount_needed, hint->inode->i_uid);
+#endif
+ quota_ret = DQUOT_ALLOC_BLOCK_NODIRTY(hint->inode, amount_needed);
+ if (quota_ret) /* Quota exceeded? */
+ return QUOTA_EXCEEDED;
+ if (hint->preallocate && hint->prealloc_size ) {
+#ifdef REISERQUOTA_DEBUG
+ reiserfs_debug (s, REISERFS_DEBUG_CODE, "reiserquota: allocating (prealloc) %d blocks id=%u", hint->prealloc_size, hint->inode->i_uid);
+#endif
+ quota_ret = DQUOT_PREALLOC_BLOCK_NODIRTY(hint->inode, hint->prealloc_size);
+ if (quota_ret)
+ hint->preallocate=hint->prealloc_size=0;
+ }
+ /* for unformatted nodes, force large allocations */
+ bigalloc = amount_needed;
+ }
+
+ do {
+ /* in bigalloc mode, nr_allocated should stay zero until
+ * the entire allocation is filled
+ */
+ if (unlikely(bigalloc && nr_allocated)) {
+ reiserfs_warning(s, "bigalloc is %d, nr_allocated %d\n",
+ bigalloc, nr_allocated);
+ /* reset things to a sane value */
+ bigalloc = amount_needed - nr_allocated;
+ }
+ /*
+ * try pass 0 and pass 1 looking for a nice big
+ * contiguous allocation. Then reset and look
+ * for anything you can find.
+ */
+ if (passno == 2 && bigalloc) {
+ passno = 0;
+ bigalloc = 0;
+ }
+ switch (passno++) {
+ case 0: /* Search from hint->search_start to end of disk */
+ start = hint->search_start;
+ finish = SB_BLOCK_COUNT(s) - 1;
+ break;
+ case 1: /* Search from hint->beg to hint->search_start */
+ start = hint->beg;
+ finish = hint->search_start;
+ break;
+ case 2: /* Last chance: Search from 0 to hint->beg */
+ start = 0;
+ finish = hint->beg;
+ break;
+ default: /* We've tried searching everywhere, not enough space */
+ /* Free the blocks */
+ if (!hint->formatted_node) {
+#ifdef REISERQUOTA_DEBUG
+ reiserfs_debug (s, REISERFS_DEBUG_CODE, "reiserquota: freeing (nospace) %d blocks id=%u", amount_needed + hint->prealloc_size - nr_allocated, hint->inode->i_uid);
+#endif
+ DQUOT_FREE_BLOCK_NODIRTY(hint->inode, amount_needed + hint->prealloc_size - nr_allocated); /* Free not allocated blocks */
+ }
+ while (nr_allocated --)
+ reiserfs_free_block(hint->th, hint->inode, new_blocknrs[nr_allocated], !hint->formatted_node);
+
+ return NO_DISK_SPACE;
+ }
+ } while ((nr_allocated += allocate_without_wrapping_disk (hint,
+ new_blocknrs + nr_allocated, start, finish,
+ bigalloc ? bigalloc : 1,
+ amount_needed - nr_allocated,
+ hint->prealloc_size))
+ < amount_needed);
+ if ( !hint->formatted_node &&
+ amount_needed + hint->prealloc_size >
+ nr_allocated + REISERFS_I(hint->inode)->i_prealloc_count) {
+ /* Some of preallocation blocks were not allocated */
+#ifdef REISERQUOTA_DEBUG
+ reiserfs_debug (s, REISERFS_DEBUG_CODE, "reiserquota: freeing (failed prealloc) %d blocks id=%u", amount_needed + hint->prealloc_size - nr_allocated - REISERFS_I(hint->inode)->i_prealloc_count, hint->inode->i_uid);
+#endif
+ DQUOT_FREE_BLOCK_NODIRTY(hint->inode, amount_needed +
+ hint->prealloc_size - nr_allocated -
+ REISERFS_I(hint->inode)->i_prealloc_count);
+ }
+
+ return CARRY_ON;
+}
+
+/* grab new blocknrs from preallocated list */
+/* return amount still needed after using them */
+static int use_preallocated_list_if_available (reiserfs_blocknr_hint_t *hint,
+ b_blocknr_t *new_blocknrs, int amount_needed)
+{
+ struct inode * inode = hint->inode;
+
+ if (REISERFS_I(inode)->i_prealloc_count > 0) {
+ while (amount_needed) {
+
+ *new_blocknrs ++ = REISERFS_I(inode)->i_prealloc_block ++;
+ REISERFS_I(inode)->i_prealloc_count --;
+
+ amount_needed --;
+
+ if (REISERFS_I(inode)->i_prealloc_count <= 0) {
+ list_del(&REISERFS_I(inode)->i_prealloc_list);
+ break;
+ }
+ }
+ }
+ /* return amount still needed after using preallocated blocks */
+ return amount_needed;
+}
+
+int reiserfs_allocate_blocknrs(reiserfs_blocknr_hint_t *hint,
+ b_blocknr_t * new_blocknrs, int amount_needed,
+ int reserved_by_us /* Amount of blocks we have
+ already reserved */)
+{
+ int initial_amount_needed = amount_needed;
+ int ret;
+ struct super_block *s = hint->th->t_super;
+
+ /* Check if there is enough space, taking into account reserved space */
+ if ( SB_FREE_BLOCKS(s) - REISERFS_SB(s)->reserved_blocks <
+ amount_needed - reserved_by_us)
+ return NO_DISK_SPACE;
+ /* should this be if !hint->inode && hint->preallocate? */
+ /* do you mean hint->formatted_node can be removed ? - Zam */
+ /* hint->formatted_node cannot be removed because we try to access
+ inode information here, and there is often no inode assotiated with
+ metadata allocations - green */
+
+ if (!hint->formatted_node && hint->preallocate) {
+ amount_needed = use_preallocated_list_if_available
+ (hint, new_blocknrs, amount_needed);
+ if (amount_needed == 0) /* all blocknrs we need we got from
+ prealloc. list */
+ return CARRY_ON;
+ new_blocknrs += (initial_amount_needed - amount_needed);
+ }
+
+ /* find search start and save it in hint structure */
+ determine_search_start(hint, amount_needed);
+ if (hint->search_start >= SB_BLOCK_COUNT(s))
+ hint->search_start = SB_BLOCK_COUNT(s) - 1;
+
+ /* allocation itself; fill new_blocknrs and preallocation arrays */
+ ret = blocknrs_and_prealloc_arrays_from_search_start
+ (hint, new_blocknrs, amount_needed);
+
+ /* we used prealloc. list to fill (partially) new_blocknrs array. If final allocation fails we
+ * need to return blocks back to prealloc. list or just free them. -- Zam (I chose second
+ * variant) */
+
+ if (ret != CARRY_ON) {
+ while (amount_needed ++ < initial_amount_needed) {
+ reiserfs_free_block(hint->th, hint->inode, *(--new_blocknrs), 1);
+ }
+ }
+ return ret;
+}
+
+/* These 2 functions are here to provide blocks reservation to the rest of kernel */
+/* Reserve @blocks amount of blocks in fs pointed by @sb. Caller must make sure
+ there are actually this much blocks on the FS available */
+void reiserfs_claim_blocks_to_be_allocated(
+ struct super_block *sb, /* super block of
+ filesystem where
+ blocks should be
+ reserved */
+ int blocks /* How much to reserve */
+ )
+{
+
+ /* Fast case, if reservation is zero - exit immediately. */
+ if ( !blocks )
+ return;
+
+ spin_lock(&REISERFS_SB(sb)->bitmap_lock);
+ REISERFS_SB(sb)->reserved_blocks += blocks;
+ spin_unlock(&REISERFS_SB(sb)->bitmap_lock);
+}
+
+/* Unreserve @blocks amount of blocks in fs pointed by @sb */
+void reiserfs_release_claimed_blocks(
+ struct super_block *sb, /* super block of
+ filesystem where
+ blocks should be
+ reserved */
+ int blocks /* How much to unreserve */
+ )
+{
+
+ /* Fast case, if unreservation is zero - exit immediately. */
+ if ( !blocks )
+ return;
+
+ spin_lock(&REISERFS_SB(sb)->bitmap_lock);
+ REISERFS_SB(sb)->reserved_blocks -= blocks;
+ spin_unlock(&REISERFS_SB(sb)->bitmap_lock);
+ RFALSE( REISERFS_SB(sb)->reserved_blocks < 0, "amount of blocks reserved became zero?");
+}
+
+/* This function estimates how much pages we will be able to write to FS
+ used for reiserfs_file_write() purposes for now. */
+int reiserfs_can_fit_pages ( struct super_block *sb /* superblock of filesystem
+ to estimate space */ )
+{
+ int space;
+
+ spin_lock(&REISERFS_SB(sb)->bitmap_lock);
+ space = (SB_FREE_BLOCKS(sb) - REISERFS_SB(sb)->reserved_blocks) >> ( PAGE_CACHE_SHIFT - sb->s_blocksize_bits);
+ spin_unlock(&REISERFS_SB(sb)->bitmap_lock);
+
+ return space>0?space:0;
+}