/*
* Build the most complicated map of extents the earth has ever seen. We want
* this so we can test all of the corner cases of btrfs_get_extent. Here is a
* diagram of how the extents will look though this may not be possible we still
* want to make sure everything acts normally (the last number is not inclusive)
*
* [0 - 5][5 - 6][ 6 - 4096 ][ 4096 - 4100][4100 - 8195][8195 - 12291]
* [hole ][inline][hole but no extent][ hole ][ regular ][regular1 split]
*
* [12291 - 16387][16387 - 24579][24579 - 28675][ 28675 - 32771][32771 - 36867 ]
* [ hole ][regular1 split][ prealloc ][ prealloc1 ][prealloc1 written]
*
* [36867 - 45059][45059 - 53251][53251 - 57347][57347 - 61443][61443- 69635]
* [ prealloc1 ][ compressed ][ compressed1 ][ regular ][ compressed1]
*
* [69635-73731][ 73731 - 86019 ][86019-90115]
* [ regular ][ hole but no extent][ regular ]
*/
static void setup_file_extents(struct btrfs_root *root, u32 sectorsize)
{
int slot = 0;
u64 disk_bytenr = SZ_1M;
u64 offset = 0;
/* First we want a hole */
insert_extent(root, offset, 5, 5, 0, 0, 0, BTRFS_FILE_EXTENT_REG, 0,
slot);
slot++;
offset += 5;
/*
* Now we want an inline extent, I don't think this is possible but hey
* why not? Also keep in mind if we have an inline extent it counts as
* the whole first page. If we were to expand it we would have to cow
* and we wouldn't have an inline extent anymore.
*/
insert_extent(root, offset, 1, 1, 0, 0, 0, BTRFS_FILE_EXTENT_INLINE, 0,
slot);
slot++;
offset = sectorsize;
/* Now another hole */
insert_extent(root, offset, 4, 4, 0, 0, 0, BTRFS_FILE_EXTENT_REG, 0,
slot);
slot++;
offset += 4;
/* Now for a regular extent */
insert_extent(root, offset, sectorsize - 1, sectorsize - 1, 0,
disk_bytenr, sectorsize, BTRFS_FILE_EXTENT_REG, 0, slot);
slot++;
disk_bytenr += sectorsize;
offset += sectorsize - 1;
/*
* Now for 3 extents that were split from a hole punch so we test
* offsets properly.
*/
insert_extent(root, offset, sectorsize, 4 * sectorsize, 0, disk_bytenr,
4 * sectorsize, BTRFS_FILE_EXTENT_REG, 0, slot);
slot++;
offset += sectorsize;
insert_extent(root, offset, sectorsize, sectorsize, 0, 0, 0,
BTRFS_FILE_EXTENT_REG, 0, slot);
slot++;
offset += sectorsize;
insert_extent(root, offset, 2 * sectorsize, 4 * sectorsize,
2 * sectorsize, disk_bytenr, 4 * sectorsize,
BTRFS_FILE_EXTENT_REG, 0, slot);
slot++;
offset += 2 * sectorsize;
disk_bytenr += 4 * sectorsize;
/* Now for a unwritten prealloc extent */
insert_extent(root, offset, sectorsize, sectorsize, 0, disk_bytenr,
sectorsize, BTRFS_FILE_EXTENT_PREALLOC, 0, slot);
slot++;
offset += sectorsize;
/*
* We want to jack up disk_bytenr a little more so the em stuff doesn't
* merge our records.
*/
disk_bytenr += 2 * sectorsize;
/*
* Now for a partially written prealloc extent, basically the same as
* the hole punch example above. Ram_bytes never changes when you mark
* extents written btw.
*/
insert_extent(root, offset, sectorsize, 4 * sectorsize, 0, disk_bytenr,
4 * sectorsize, BTRFS_FILE_EXTENT_PREALLOC, 0, slot);
slot++;
offset += sectorsize;
insert_extent(root, offset, sectorsize, 4 * sectorsize, sectorsize,
disk_bytenr, 4 * sectorsize, BTRFS_FILE_EXTENT_REG, 0,
slot);
slot++;
offset += sectorsize;
insert_extent(root, offset, 2 * sectorsize, 4 * sectorsize,
2 * sectorsize, disk_bytenr, 4 * sectorsize,
BTRFS_FILE_EXTENT_PREALLOC, 0, slot);
slot++;
offset += 2 * sectorsize;
disk_bytenr += 4 * sectorsize;
/* Now a normal compressed extent */
insert_extent(root, offset, 2 * sectorsize, 2 * sectorsize, 0,
disk_bytenr, sectorsize, BTRFS_FILE_EXTENT_REG,
BTRFS_COMPRESS_ZLIB, slot);
slot++;
offset += 2 * sectorsize;
/* No merges */
disk_bytenr += 2 * sectorsize;
/* Now a split compressed extent */
insert_extent(root, offset, sectorsize, 4 * sectorsize, 0, disk_bytenr,
sectorsize, BTRFS_FILE_EXTENT_REG,
BTRFS_COMPRESS_ZLIB, slot);
slot++;
offset += sectorsize;
insert_extent(root, offset, sectorsize, sectorsize, 0,
disk_bytenr + sectorsize, sectorsize,
BTRFS_FILE_EXTENT_REG, 0, slot);
slot++;
offset += sectorsize;
insert_extent(root, offset, 2 * sectorsize, 4 * sectorsize,
2 * sectorsize, disk_bytenr, sectorsize,
BTRFS_FILE_EXTENT_REG, BTRFS_COMPRESS_ZLIB, slot);
slot++;
offset += 2 * sectorsize;
disk_bytenr += 2 * sectorsize;
/* Now extents that have a hole but no hole extent */
insert_extent(root, offset, sectorsize, sectorsize, 0, disk_bytenr,
sectorsize, BTRFS_FILE_EXTENT_REG, 0, slot);
slot++;
offset += 4 * sectorsize;
disk_bytenr += sectorsize;
insert_extent(root, offset, sectorsize, sectorsize, 0, disk_bytenr,
sectorsize, BTRFS_FILE_EXTENT_REG, 0, slot);
}
static int test_hole_first(u32 sectorsize, u32 nodesize)
{
struct btrfs_fs_info *fs_info = NULL;
struct inode *inode = NULL;
struct btrfs_root *root = NULL;
struct extent_map *em = NULL;
int ret = -ENOMEM;
inode = btrfs_new_test_inode();
if (!inode) {
test_msg("Couldn't allocate inode\n");
return ret;
}
BTRFS_I(inode)->location.type = BTRFS_INODE_ITEM_KEY;
BTRFS_I(inode)->location.objectid = BTRFS_FIRST_FREE_OBJECTID;
BTRFS_I(inode)->location.offset = 0;
fs_info = btrfs_alloc_dummy_fs_info();
if (!fs_info) {
test_msg("Couldn't allocate dummy fs info\n");
goto out;
}
root = btrfs_alloc_dummy_root(fs_info, sectorsize, nodesize);
if (IS_ERR(root)) {
test_msg("Couldn't allocate root\n");
goto out;
}
root->node = alloc_dummy_extent_buffer(NULL, nodesize, nodesize);
if (!root->node) {
test_msg("Couldn't allocate dummy buffer\n");
goto out;
}
extent_buffer_get(root->node);
btrfs_set_header_nritems(root->node, 0);
btrfs_set_header_level(root->node, 0);
BTRFS_I(inode)->root = root;
ret = -EINVAL;
/*
* Need a blank inode item here just so we don't confuse
* btrfs_get_extent.
*/
insert_inode_item_key(root);
insert_extent(root, sectorsize, sectorsize, sectorsize, 0, sectorsize,
sectorsize, BTRFS_FILE_EXTENT_REG, 0, 1);
em = btrfs_get_extent(inode, NULL, 0, 0, 2 * sectorsize, 0);
if (IS_ERR(em)) {
test_msg("Got an error when we shouldn't have\n");
goto out;
}
if (em->block_start != EXTENT_MAP_HOLE) {
test_msg("Expected a hole, got %llu\n", em->block_start);
goto out;
}
if (em->start != 0 || em->len != sectorsize) {
test_msg("Unexpected extent wanted start 0 len %u, "
"got start %llu len %llu\n",
sectorsize, em->start, em->len);
goto out;
}
if (em->flags != vacancy_only) {
test_msg("Wrong flags, wanted %lu, have %lu\n", vacancy_only,
em->flags);
goto out;
}
free_extent_map(em);
em = btrfs_get_extent(inode, NULL, 0, sectorsize, 2 * sectorsize, 0);
if (IS_ERR(em)) {
test_msg("Got an error when we shouldn't have\n");
goto out;
}
if (em->block_start != sectorsize) {
test_msg("Expected a real extent, got %llu\n", em->block_start);
goto out;
}
if (em->start != sectorsize || em->len != sectorsize) {
test_msg("Unexpected extent wanted start %u len %u, "
"got start %llu len %llu\n",
sectorsize, sectorsize, em->start, em->len);
goto out;
}
if (em->flags != 0) {
test_msg("Unexpected flags set, wanted 0 got %lu\n",
em->flags);
goto out;
}
ret = 0;
out:
if (!IS_ERR(em))
free_extent_map(em);
iput(inode);
btrfs_free_dummy_root(root);
btrfs_free_dummy_fs_info(fs_info);
return ret;
}
/* Insert extent E into the tree rooted at extent ROOT. The row-positions
in E are assumed to be relative to the row-position of ROOT. */
static void
insert_extent(Lisp_Extent *e, Lisp_Extent *root)
{
Lisp_Extent *x;
top:
x = root->first_child;
while(x != 0)
{
if(PPOS_LESS_EQUAL_P(&e->end, &x->start))
{
/* Insert E before X */
e->parent = root;
e->left_sibling = x->left_sibling;
if(e->left_sibling != 0)
e->left_sibling->right_sibling = e;
x->left_sibling = e;
e->right_sibling = x;
if(root->first_child == x)
root->first_child = e;
assert_invariants (e);
assert_invariants (x);
return;
}
else if(PPOS_LESS_P(&e->start, &x->start))
{
/* X overlaps E. The end of E clashes with the start of X.
Break E into two fragments, insert the first before X,
the second within X. */
Lisp_Extent *frag = alloc_extent(e);
frag->end = x->start;
e->start = x->start;
frag->car |= EXTFF_OPEN_END;
frag->frag_pred = e->frag_pred;
if(e->frag_pred != 0)
e->frag_pred->frag_next = frag;
frag->frag_next = e;
e->frag_pred = frag;
assert_invariants (e);
assert_invariants (x);
assert_invariants (frag);
insert_extent(frag, x->parent);
assert_invariants (e);
assert_invariants (x);
assert_invariants (frag);
continue;
}
else if(PPOS_LESS_P(&e->start, &x->end))
{
/* E starts before X ends. */
if(PPOS_LESS_EQUAL_P(&e->end, &x->end))
{
/* But E ends before X ends. So insert E in X. */
e->start.row -= x->start.row;
e->end.row -= x->start.row;
root = x;
goto top;
}
else
{
/* E ends after X ends. So break E into two frags. */
Lisp_Extent *frag = alloc_extent(e);
frag->start = x->end;
e->end = x->end;
frag->car |= EXTFF_OPEN_START;
frag->frag_next = e->frag_next;
if(e->frag_next != 0)
e->frag_next->frag_pred = frag;
frag->frag_pred = e;
e->frag_next = frag;
e->start.row -= x->start.row;
e->end.row -= x->start.row;
assert_invariants (e);
assert_invariants (x);
assert_invariants (frag);
insert_extent(e, x);
assert_invariants (e);
assert_invariants (x);
assert_invariants (frag);
e = frag;
continue;
}
}
else
{
/* X ends before E starts, keep going.. */
}
x = x->right_sibling;
}
/* Insert e at the end of the root. */
e->parent = root;
e->left_sibling = root->last_child;
if(root->last_child != 0)
root->last_child->right_sibling = e;
root->last_child = e;
if(root->first_child == 0)
root->first_child = e;
assert_invariants (e);
assert_invariants (root);
}