#include <linux/uio.h>
#include <linux/magic.h>
#include <linux/iversion.h>
+#include <linux/swap.h>
#include <asm/unaligned.h>
#include "ctree.h"
#include "disk-io.h"
* extent_clear_unlock_delalloc() to clear both the bits EXTENT_DO_ACCOUNTING
* and EXTENT_DELALLOC simultaneously, because that causes the reserved metadata
* to be released, which we want to happen only when finishing the ordered
- * extent (btrfs_finish_ordered_io()). Also note that the caller of the
- * fill_delalloc() callback already does proper cleanup for the first page of
+ * extent (btrfs_finish_ordered_io()). Also note that the caller of
+ * btrfs_run_delalloc_range already does proper cleanup for the first page of
* the range, that is, it invokes the callback writepage_end_io_hook() for the
* range of the first page.
*/
ins.offset, async_extent->pages,
async_extent->nr_pages,
async_cow->write_flags)) {
- struct extent_io_tree *tree = &BTRFS_I(inode)->io_tree;
struct page *p = async_extent->pages[0];
const u64 start = async_extent->start;
const u64 end = start + async_extent->ram_size - 1;
p->mapping = inode->i_mapping;
- tree->ops->writepage_end_io_hook(p, start, end,
- NULL, 0);
+ btrfs_writepage_endio_finish_ordered(p, start, end, 0);
+
p->mapping = NULL;
extent_clear_unlock_delalloc(inode, start, end, end,
NULL, 0,
}
/*
- * extent_io.c call back to do delayed allocation processing
+ * Function to process delayed allocation (create CoW) for ranges which are
+ * being touched for the first time.
*/
-static int run_delalloc_range(void *private_data, struct page *locked_page,
- u64 start, u64 end, int *page_started,
- unsigned long *nr_written,
- struct writeback_control *wbc)
+int btrfs_run_delalloc_range(void *private_data, struct page *locked_page,
+ u64 start, u64 end, int *page_started, unsigned long *nr_written,
+ struct writeback_control *wbc)
{
struct inode *inode = private_data;
int ret;
return ret;
}
-static void btrfs_split_extent_hook(void *private_data,
- struct extent_state *orig, u64 split)
+void btrfs_split_delalloc_extent(struct inode *inode,
+ struct extent_state *orig, u64 split)
{
- struct inode *inode = private_data;
u64 size;
/* not delalloc, ignore it */
u64 new_size;
/*
- * See the explanation in btrfs_merge_extent_hook, the same
+ * See the explanation in btrfs_merge_delalloc_extent, the same
* applies here, just in reverse.
*/
new_size = orig->end - split + 1;
}
/*
- * extent_io.c merge_extent_hook, used to track merged delayed allocation
- * extents so we can keep track of new extents that are just merged onto old
- * extents, such as when we are doing sequential writes, so we can properly
- * account for the metadata space we'll need.
+ * Handle merged delayed allocation extents so we can keep track of new extents
+ * that are just merged onto old extents, such as when we are doing sequential
+ * writes, so we can properly account for the metadata space we'll need.
*/
-static void btrfs_merge_extent_hook(void *private_data,
- struct extent_state *new,
- struct extent_state *other)
+void btrfs_merge_delalloc_extent(struct inode *inode, struct extent_state *new,
+ struct extent_state *other)
{
- struct inode *inode = private_data;
u64 new_size, old_size;
u32 num_extents;
}
/*
- * extent_io.c set_bit_hook, used to track delayed allocation
- * bytes in this file, and to maintain the list of inodes that
- * have pending delalloc work to be done.
+ * Properly track delayed allocation bytes in the inode and to maintain the
+ * list of inodes that have pending delalloc work to be done.
*/
-static void btrfs_set_bit_hook(void *private_data,
- struct extent_state *state, unsigned *bits)
+void btrfs_set_delalloc_extent(struct inode *inode, struct extent_state *state,
+ unsigned *bits)
{
- struct inode *inode = private_data;
-
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
if ((*bits & EXTENT_DEFRAG) && !(*bits & EXTENT_DELALLOC))
}
/*
- * extent_io.c clear_bit_hook, see set_bit_hook for why
+ * Once a range is no longer delalloc this function ensures that proper
+ * accounting happens.
*/
-static void btrfs_clear_bit_hook(void *private_data,
- struct extent_state *state,
- unsigned *bits)
+void btrfs_clear_delalloc_extent(struct inode *vfs_inode,
+ struct extent_state *state, unsigned *bits)
{
- struct btrfs_inode *inode = BTRFS_I((struct inode *)private_data);
- struct btrfs_fs_info *fs_info = btrfs_sb(inode->vfs_inode.i_sb);
+ struct btrfs_inode *inode = BTRFS_I(vfs_inode);
+ struct btrfs_fs_info *fs_info = btrfs_sb(vfs_inode->i_sb);
u64 len = state->end + 1 - state->start;
u32 num_extents = count_max_extents(len);
return 0;
}
-/*
- * in order to insert checksums into the metadata in large chunks,
- * we wait until bio submission time. All the pages in the bio are
- * checksummed and sums are attached onto the ordered extent record.
- *
- * At IO completion time the cums attached on the ordered extent record
- * are inserted into the btree
- */
-blk_status_t btrfs_submit_bio_done(void *private_data, struct bio *bio,
- int mirror_num)
-{
- struct inode *inode = private_data;
- struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
- blk_status_t ret;
-
- ret = btrfs_map_bio(fs_info, bio, mirror_num, 1);
- if (ret) {
- bio->bi_status = ret;
- bio_endio(bio);
- }
- return ret;
-}
-
/*
* extent_io.c submission hook. This does the right thing for csum calculation
* on write, or reading the csums from the tree before a read.
* to fix it up. The async helper will wait for ordered extents, set
* the delalloc bit and make it safe to write the page.
*/
-static int btrfs_writepage_start_hook(struct page *page, u64 start, u64 end)
+int btrfs_writepage_cow_fixup(struct page *page, u64 start, u64 end)
{
struct inode *inode = page->mapping->host;
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
btrfs_finish_ordered_io(ordered_extent);
}
-static void btrfs_writepage_end_io_hook(struct page *page, u64 start, u64 end,
- struct extent_state *state, int uptodate)
+void btrfs_writepage_endio_finish_ordered(struct page *page, u64 start,
+ u64 end, int uptodate)
{
struct inode *inode = page->mapping->host;
struct btrfs_fs_info *fs_info = btrfs_sb(inode->i_sb);
struct btrfs_trans_handle *trans;
struct btrfs_root *root = BTRFS_I(dir)->root;
int err = 0;
- int drop_on_err = 0;
u64 objectid = 0;
u64 index = 0;
goto out_fail;
}
- drop_on_err = 1;
/* these must be set before we unlock the inode */
inode->i_op = &btrfs_dir_inode_operations;
inode->i_fop = &btrfs_dir_file_operations;
goto out_fail;
d_instantiate_new(dentry, inode);
- drop_on_err = 0;
out_fail:
btrfs_end_transaction(trans);
* some fairly slow code that needs optimization. This walks the list
* of all the inodes with pending delalloc and forces them to disk.
*/
-static int start_delalloc_inodes(struct btrfs_root *root, int nr)
+static int start_delalloc_inodes(struct btrfs_root *root, int nr, bool snapshot)
{
struct btrfs_inode *binode;
struct inode *inode;
}
spin_unlock(&root->delalloc_lock);
+ if (snapshot)
+ set_bit(BTRFS_INODE_SNAPSHOT_FLUSH,
+ &binode->runtime_flags);
work = btrfs_alloc_delalloc_work(inode);
if (!work) {
iput(inode);
return ret;
}
-int btrfs_start_delalloc_inodes(struct btrfs_root *root)
+int btrfs_start_delalloc_snapshot(struct btrfs_root *root)
{
struct btrfs_fs_info *fs_info = root->fs_info;
int ret;
if (test_bit(BTRFS_FS_STATE_ERROR, &fs_info->fs_state))
return -EROFS;
- ret = start_delalloc_inodes(root, -1);
+ ret = start_delalloc_inodes(root, -1, true);
if (ret > 0)
ret = 0;
return ret;
&fs_info->delalloc_roots);
spin_unlock(&fs_info->delalloc_root_lock);
- ret = start_delalloc_inodes(root, nr);
+ ret = start_delalloc_inodes(root, nr, false);
btrfs_put_fs_root(root);
if (ret < 0)
goto out;
return -EAGAIN;
}
-static void btrfs_check_extent_io_range(void *private_data, const char *caller,
- u64 start, u64 end)
-{
- struct inode *inode = private_data;
- u64 isize;
-
- isize = i_size_read(inode);
- if (end >= PAGE_SIZE && (end % 2) == 0 && end != isize - 1) {
- btrfs_debug_rl(BTRFS_I(inode)->root->fs_info,
- "%s: ino %llu isize %llu odd range [%llu,%llu]",
- caller, btrfs_ino(BTRFS_I(inode)), isize, start, end);
- }
-}
-
void btrfs_set_range_writeback(struct extent_io_tree *tree, u64 start, u64 end)
{
struct inode *inode = tree->private_data;
}
}
+#ifdef CONFIG_SWAP
+/*
+ * Add an entry indicating a block group or device which is pinned by a
+ * swapfile. Returns 0 on success, 1 if there is already an entry for it, or a
+ * negative errno on failure.
+ */
+static int btrfs_add_swapfile_pin(struct inode *inode, void *ptr,
+ bool is_block_group)
+{
+ struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
+ struct btrfs_swapfile_pin *sp, *entry;
+ struct rb_node **p;
+ struct rb_node *parent = NULL;
+
+ sp = kmalloc(sizeof(*sp), GFP_NOFS);
+ if (!sp)
+ return -ENOMEM;
+ sp->ptr = ptr;
+ sp->inode = inode;
+ sp->is_block_group = is_block_group;
+
+ spin_lock(&fs_info->swapfile_pins_lock);
+ p = &fs_info->swapfile_pins.rb_node;
+ while (*p) {
+ parent = *p;
+ entry = rb_entry(parent, struct btrfs_swapfile_pin, node);
+ if (sp->ptr < entry->ptr ||
+ (sp->ptr == entry->ptr && sp->inode < entry->inode)) {
+ p = &(*p)->rb_left;
+ } else if (sp->ptr > entry->ptr ||
+ (sp->ptr == entry->ptr && sp->inode > entry->inode)) {
+ p = &(*p)->rb_right;
+ } else {
+ spin_unlock(&fs_info->swapfile_pins_lock);
+ kfree(sp);
+ return 1;
+ }
+ }
+ rb_link_node(&sp->node, parent, p);
+ rb_insert_color(&sp->node, &fs_info->swapfile_pins);
+ spin_unlock(&fs_info->swapfile_pins_lock);
+ return 0;
+}
+
+/* Free all of the entries pinned by this swapfile. */
+static void btrfs_free_swapfile_pins(struct inode *inode)
+{
+ struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
+ struct btrfs_swapfile_pin *sp;
+ struct rb_node *node, *next;
+
+ spin_lock(&fs_info->swapfile_pins_lock);
+ node = rb_first(&fs_info->swapfile_pins);
+ while (node) {
+ next = rb_next(node);
+ sp = rb_entry(node, struct btrfs_swapfile_pin, node);
+ if (sp->inode == inode) {
+ rb_erase(&sp->node, &fs_info->swapfile_pins);
+ if (sp->is_block_group)
+ btrfs_put_block_group(sp->ptr);
+ kfree(sp);
+ }
+ node = next;
+ }
+ spin_unlock(&fs_info->swapfile_pins_lock);
+}
+
+struct btrfs_swap_info {
+ u64 start;
+ u64 block_start;
+ u64 block_len;
+ u64 lowest_ppage;
+ u64 highest_ppage;
+ unsigned long nr_pages;
+ int nr_extents;
+};
+
+static int btrfs_add_swap_extent(struct swap_info_struct *sis,
+ struct btrfs_swap_info *bsi)
+{
+ unsigned long nr_pages;
+ u64 first_ppage, first_ppage_reported, next_ppage;
+ int ret;
+
+ first_ppage = ALIGN(bsi->block_start, PAGE_SIZE) >> PAGE_SHIFT;
+ next_ppage = ALIGN_DOWN(bsi->block_start + bsi->block_len,
+ PAGE_SIZE) >> PAGE_SHIFT;
+
+ if (first_ppage >= next_ppage)
+ return 0;
+ nr_pages = next_ppage - first_ppage;
+
+ first_ppage_reported = first_ppage;
+ if (bsi->start == 0)
+ first_ppage_reported++;
+ if (bsi->lowest_ppage > first_ppage_reported)
+ bsi->lowest_ppage = first_ppage_reported;
+ if (bsi->highest_ppage < (next_ppage - 1))
+ bsi->highest_ppage = next_ppage - 1;
+
+ ret = add_swap_extent(sis, bsi->nr_pages, nr_pages, first_ppage);
+ if (ret < 0)
+ return ret;
+ bsi->nr_extents += ret;
+ bsi->nr_pages += nr_pages;
+ return 0;
+}
+
+static void btrfs_swap_deactivate(struct file *file)
+{
+ struct inode *inode = file_inode(file);
+
+ btrfs_free_swapfile_pins(inode);
+ atomic_dec(&BTRFS_I(inode)->root->nr_swapfiles);
+}
+
+static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file,
+ sector_t *span)
+{
+ struct inode *inode = file_inode(file);
+ struct btrfs_fs_info *fs_info = BTRFS_I(inode)->root->fs_info;
+ struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
+ struct extent_state *cached_state = NULL;
+ struct extent_map *em = NULL;
+ struct btrfs_device *device = NULL;
+ struct btrfs_swap_info bsi = {
+ .lowest_ppage = (sector_t)-1ULL,
+ };
+ int ret = 0;
+ u64 isize;
+ u64 start;
+
+ /*
+ * If the swap file was just created, make sure delalloc is done. If the
+ * file changes again after this, the user is doing something stupid and
+ * we don't really care.
+ */
+ ret = btrfs_wait_ordered_range(inode, 0, (u64)-1);
+ if (ret)
+ return ret;
+
+ /*
+ * The inode is locked, so these flags won't change after we check them.
+ */
+ if (BTRFS_I(inode)->flags & BTRFS_INODE_COMPRESS) {
+ btrfs_warn(fs_info, "swapfile must not be compressed");
+ return -EINVAL;
+ }
+ if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATACOW)) {
+ btrfs_warn(fs_info, "swapfile must not be copy-on-write");
+ return -EINVAL;
+ }
+ if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
+ btrfs_warn(fs_info, "swapfile must not be checksummed");
+ return -EINVAL;
+ }
+
+ /*
+ * Balance or device remove/replace/resize can move stuff around from
+ * under us. The EXCL_OP flag makes sure they aren't running/won't run
+ * concurrently while we are mapping the swap extents, and
+ * fs_info->swapfile_pins prevents them from running while the swap file
+ * is active and moving the extents. Note that this also prevents a
+ * concurrent device add which isn't actually necessary, but it's not
+ * really worth the trouble to allow it.
+ */
+ if (test_and_set_bit(BTRFS_FS_EXCL_OP, &fs_info->flags)) {
+ btrfs_warn(fs_info,
+ "cannot activate swapfile while exclusive operation is running");
+ return -EBUSY;
+ }
+ /*
+ * Snapshots can create extents which require COW even if NODATACOW is
+ * set. We use this counter to prevent snapshots. We must increment it
+ * before walking the extents because we don't want a concurrent
+ * snapshot to run after we've already checked the extents.
+ */
+ atomic_inc(&BTRFS_I(inode)->root->nr_swapfiles);
+
+ isize = ALIGN_DOWN(inode->i_size, fs_info->sectorsize);
+
+ lock_extent_bits(io_tree, 0, isize - 1, &cached_state);
+ start = 0;
+ while (start < isize) {
+ u64 logical_block_start, physical_block_start;
+ struct btrfs_block_group_cache *bg;
+ u64 len = isize - start;
+
+ em = btrfs_get_extent(BTRFS_I(inode), NULL, 0, start, len, 0);
+ if (IS_ERR(em)) {
+ ret = PTR_ERR(em);
+ goto out;
+ }
+
+ if (em->block_start == EXTENT_MAP_HOLE) {
+ btrfs_warn(fs_info, "swapfile must not have holes");
+ ret = -EINVAL;
+ goto out;
+ }
+ if (em->block_start == EXTENT_MAP_INLINE) {
+ /*
+ * It's unlikely we'll ever actually find ourselves
+ * here, as a file small enough to fit inline won't be
+ * big enough to store more than the swap header, but in
+ * case something changes in the future, let's catch it
+ * here rather than later.
+ */
+ btrfs_warn(fs_info, "swapfile must not be inline");
+ ret = -EINVAL;
+ goto out;
+ }
+ if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags)) {
+ btrfs_warn(fs_info, "swapfile must not be compressed");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ logical_block_start = em->block_start + (start - em->start);
+ len = min(len, em->len - (start - em->start));
+ free_extent_map(em);
+ em = NULL;
+
+ ret = can_nocow_extent(inode, start, &len, NULL, NULL, NULL);
+ if (ret < 0) {
+ goto out;
+ } else if (ret) {
+ ret = 0;
+ } else {
+ btrfs_warn(fs_info,
+ "swapfile must not be copy-on-write");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ em = btrfs_get_chunk_map(fs_info, logical_block_start, len);
+ if (IS_ERR(em)) {
+ ret = PTR_ERR(em);
+ goto out;
+ }
+
+ if (em->map_lookup->type & BTRFS_BLOCK_GROUP_PROFILE_MASK) {
+ btrfs_warn(fs_info,
+ "swapfile must have single data profile");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ if (device == NULL) {
+ device = em->map_lookup->stripes[0].dev;
+ ret = btrfs_add_swapfile_pin(inode, device, false);
+ if (ret == 1)
+ ret = 0;
+ else if (ret)
+ goto out;
+ } else if (device != em->map_lookup->stripes[0].dev) {
+ btrfs_warn(fs_info, "swapfile must be on one device");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ physical_block_start = (em->map_lookup->stripes[0].physical +
+ (logical_block_start - em->start));
+ len = min(len, em->len - (logical_block_start - em->start));
+ free_extent_map(em);
+ em = NULL;
+
+ bg = btrfs_lookup_block_group(fs_info, logical_block_start);
+ if (!bg) {
+ btrfs_warn(fs_info,
+ "could not find block group containing swapfile");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ ret = btrfs_add_swapfile_pin(inode, bg, true);
+ if (ret) {
+ btrfs_put_block_group(bg);
+ if (ret == 1)
+ ret = 0;
+ else
+ goto out;
+ }
+
+ if (bsi.block_len &&
+ bsi.block_start + bsi.block_len == physical_block_start) {
+ bsi.block_len += len;
+ } else {
+ if (bsi.block_len) {
+ ret = btrfs_add_swap_extent(sis, &bsi);
+ if (ret)
+ goto out;
+ }
+ bsi.start = start;
+ bsi.block_start = physical_block_start;
+ bsi.block_len = len;
+ }
+
+ start += len;
+ }
+
+ if (bsi.block_len)
+ ret = btrfs_add_swap_extent(sis, &bsi);
+
+out:
+ if (!IS_ERR_OR_NULL(em))
+ free_extent_map(em);
+
+ unlock_extent_cached(io_tree, 0, isize - 1, &cached_state);
+
+ if (ret)
+ btrfs_swap_deactivate(file);
+
+ clear_bit(BTRFS_FS_EXCL_OP, &fs_info->flags);
+
+ if (ret)
+ return ret;
+
+ if (device)
+ sis->bdev = device->bdev;
+ *span = bsi.highest_ppage - bsi.lowest_ppage + 1;
+ sis->max = bsi.nr_pages;
+ sis->pages = bsi.nr_pages - 1;
+ sis->highest_bit = bsi.nr_pages - 1;
+ return bsi.nr_extents;
+}
+#else
+static void btrfs_swap_deactivate(struct file *file)
+{
+}
+
+static int btrfs_swap_activate(struct swap_info_struct *sis, struct file *file,
+ sector_t *span)
+{
+ return -EOPNOTSUPP;
+}
+#endif
+
static const struct inode_operations btrfs_dir_inode_operations = {
.getattr = btrfs_getattr,
.lookup = btrfs_lookup,
.submit_bio_hook = btrfs_submit_bio_hook,
.readpage_end_io_hook = btrfs_readpage_end_io_hook,
.readpage_io_failed_hook = btrfs_readpage_io_failed_hook,
-
- /* optional callbacks */
- .fill_delalloc = run_delalloc_range,
- .writepage_end_io_hook = btrfs_writepage_end_io_hook,
- .writepage_start_hook = btrfs_writepage_start_hook,
- .set_bit_hook = btrfs_set_bit_hook,
- .clear_bit_hook = btrfs_clear_bit_hook,
- .merge_extent_hook = btrfs_merge_extent_hook,
- .split_extent_hook = btrfs_split_extent_hook,
- .check_extent_io_range = btrfs_check_extent_io_range,
};
/*
.releasepage = btrfs_releasepage,
.set_page_dirty = btrfs_set_page_dirty,
.error_remove_page = generic_error_remove_page,
+ .swap_activate = btrfs_swap_activate,
+ .swap_deactivate = btrfs_swap_deactivate,
};
static const struct inode_operations btrfs_file_inode_operations = {
git.samba.org / sfrench / cifs-2.6.git / blobdiff