Darrick J. Wong
2016-Nov-09 22:51 UTC
[Ocfs2-devel] [PATCH 6/6] ocfs2: implement the VFS clone_range, copy_range, and dedupe_range features
Connect the new VFS clone_range, copy_range, and dedupe_range features
to the existing reflink capability of ocfs2. Compared to the existing
ocfs2 reflink ioctl We have to do things a little differently to support
the VFS semantics (we can clone subranges of a file but we don't clone
xattrs), but the VFS ioctls are more broadly supported.
Signed-off-by: Darrick J. Wong <darrick.wong at oracle.com>
---
fs/ocfs2/file.c | 62 ++++-
fs/ocfs2/file.h | 3
fs/ocfs2/refcounttree.c | 619 +++++++++++++++++++++++++++++++++++++++++++++++
fs/ocfs2/refcounttree.h | 7 +
4 files changed, 688 insertions(+), 3 deletions(-)
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index 000c234..d5a022d 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1667,9 +1667,9 @@ static void ocfs2_calc_trunc_pos(struct inode *inode,
*done = ret;
}
-static int ocfs2_remove_inode_range(struct inode *inode,
- struct buffer_head *di_bh, u64 byte_start,
- u64 byte_len)
+int ocfs2_remove_inode_range(struct inode *inode,
+ struct buffer_head *di_bh, u64 byte_start,
+ u64 byte_len)
{
int ret = 0, flags = 0, done = 0, i;
u32 trunc_start, trunc_len, trunc_end, trunc_cpos, phys_cpos;
@@ -2440,6 +2440,56 @@ static loff_t ocfs2_file_llseek(struct file *file, loff_t
offset, int whence)
return offset;
}
+static ssize_t ocfs2_file_copy_range(struct file *file_in,
+ loff_t pos_in,
+ struct file *file_out,
+ loff_t pos_out,
+ size_t len,
+ unsigned int flags)
+{
+ int error;
+
+ error = ocfs2_reflink_remap_range(file_in, pos_in, file_out, pos_out,
+ len, false);
+ if (error)
+ return error;
+ return len;
+}
+
+static int ocfs2_file_clone_range(struct file *file_in,
+ loff_t pos_in,
+ struct file *file_out,
+ loff_t pos_out,
+ u64 len)
+{
+ return ocfs2_reflink_remap_range(file_in, pos_in, file_out, pos_out,
+ len, false);
+}
+
+#define OCFS2_MAX_DEDUPE_LEN (16 * 1024 * 1024)
+static ssize_t ocfs2_file_dedupe_range(struct file *src_file,
+ u64 loff,
+ u64 len,
+ struct file *dst_file,
+ u64 dst_loff)
+{
+ int error;
+
+ /*
+ * Limit the total length we will dedupe for each operation.
+ * This is intended to bound the total time spent in this
+ * ioctl to something sane.
+ */
+ if (len > OCFS2_MAX_DEDUPE_LEN)
+ len = OCFS2_MAX_DEDUPE_LEN;
+
+ error = ocfs2_reflink_remap_range(src_file, loff, dst_file, dst_loff,
+ len, true);
+ if (error)
+ return error;
+ return len;
+}
+
const struct inode_operations ocfs2_file_iops = {
.setattr = ocfs2_setattr,
.getattr = ocfs2_getattr,
@@ -2479,6 +2529,9 @@ const struct file_operations ocfs2_fops = {
.splice_read = generic_file_splice_read,
.splice_write = iter_file_splice_write,
.fallocate = ocfs2_fallocate,
+ .copy_file_range = ocfs2_file_copy_range,
+ .clone_file_range = ocfs2_file_clone_range,
+ .dedupe_file_range = ocfs2_file_dedupe_range,
};
const struct file_operations ocfs2_dops = {
@@ -2524,6 +2577,9 @@ const struct file_operations ocfs2_fops_no_plocks = {
.splice_read = generic_file_splice_read,
.splice_write = iter_file_splice_write,
.fallocate = ocfs2_fallocate,
+ .copy_file_range = ocfs2_file_copy_range,
+ .clone_file_range = ocfs2_file_clone_range,
+ .dedupe_file_range = ocfs2_file_dedupe_range,
};
const struct file_operations ocfs2_dops_no_plocks = {
diff --git a/fs/ocfs2/file.h b/fs/ocfs2/file.h
index e8c62f2..897fd9a 100644
--- a/fs/ocfs2/file.h
+++ b/fs/ocfs2/file.h
@@ -82,4 +82,7 @@ int ocfs2_change_file_space(struct file *file, unsigned int
cmd,
int ocfs2_check_range_for_refcount(struct inode *inode, loff_t pos,
size_t count);
+int ocfs2_remove_inode_range(struct inode *inode,
+ struct buffer_head *di_bh, u64 byte_start,
+ u64 byte_len);
#endif /* OCFS2_FILE_H */
diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
index d92b6c6..3e2198c 100644
--- a/fs/ocfs2/refcounttree.c
+++ b/fs/ocfs2/refcounttree.c
@@ -34,6 +34,7 @@
#include "xattr.h"
#include "namei.h"
#include "ocfs2_trace.h"
+#include "file.h"
#include <linux/bio.h>
#include <linux/blkdev.h>
@@ -4447,3 +4448,621 @@ int ocfs2_reflink_ioctl(struct inode *inode,
return error;
}
+
+/* Update destination inode size, if necessary. */
+static int ocfs2_reflink_update_dest(struct inode *dest,
+ struct buffer_head *d_bh,
+ loff_t newlen)
+{
+ handle_t *handle;
+ struct ocfs2_dinode *di = (struct ocfs2_dinode *)d_bh->b_data;
+ int ret;
+
+ if (newlen <= i_size_read(dest))
+ return 0;
+
+ handle = ocfs2_start_trans(OCFS2_SB(dest->i_sb),
+ OCFS2_INODE_UPDATE_CREDITS);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ return ret;
+ }
+
+ ret = ocfs2_journal_access_di(handle, INODE_CACHE(dest), d_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+ spin_lock(&OCFS2_I(dest)->ip_lock);
+ if (newlen > i_size_read(dest)) {
+ i_size_write(dest, newlen);
+ di->i_size = newlen;
+ }
+ spin_unlock(&OCFS2_I(dest)->ip_lock);
+
+ ocfs2_journal_dirty(handle, d_bh);
+
+out_commit:
+ ocfs2_commit_trans(OCFS2_SB(dest->i_sb), handle);
+ return ret;
+}
+
+/* Remap the range pos_in:len in s_inode to pos_out:len in t_inode. */
+static int ocfs2_reflink_remap_extent(struct inode *s_inode,
+ struct buffer_head *s_bh,
+ loff_t pos_in,
+ struct inode *t_inode,
+ struct buffer_head *t_bh,
+ loff_t pos_out,
+ loff_t len,
+ struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+ struct ocfs2_extent_tree s_et;
+ struct ocfs2_extent_tree t_et;
+ struct ocfs2_dinode *dis;
+ struct buffer_head *ref_root_bh = NULL;
+ struct ocfs2_refcount_tree *ref_tree;
+ struct ocfs2_super *osb;
+ loff_t pstart, plen;
+ u32 p_cluster, num_clusters, slast, spos, tpos;
+ unsigned int ext_flags;
+ int ret = 0;
+
+ osb = OCFS2_SB(s_inode->i_sb);
+ dis = (struct ocfs2_dinode *)s_bh->b_data;
+ ocfs2_init_dinode_extent_tree(&s_et, INODE_CACHE(s_inode), s_bh);
+ ocfs2_init_dinode_extent_tree(&t_et, INODE_CACHE(t_inode), t_bh);
+
+ spos = ocfs2_bytes_to_clusters(s_inode->i_sb, pos_in);
+ tpos = ocfs2_bytes_to_clusters(t_inode->i_sb, pos_out);
+ slast = ocfs2_clusters_for_bytes(s_inode->i_sb, pos_in + len);
+
+ while (spos < slast) {
+ if (fatal_signal_pending(current)) {
+ ret = -EINTR;
+ goto out;
+ }
+
+ /* Look up the extent. */
+ ret = ocfs2_get_clusters(s_inode, spos, &p_cluster,
+ &num_clusters, &ext_flags);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ num_clusters = min_t(u32, num_clusters, slast - spos);
+
+ /* Punch out the dest range. */
+ pstart = ocfs2_clusters_to_bytes(t_inode->i_sb, tpos);
+ plen = ocfs2_clusters_to_bytes(t_inode->i_sb, num_clusters);
+ ret = ocfs2_remove_inode_range(t_inode, t_bh, pstart, plen);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (p_cluster == 0)
+ goto next_loop;
+
+ /* Lock the refcount btree... */
+ ret = ocfs2_lock_refcount_tree(osb,
+ le64_to_cpu(dis->i_refcount_loc),
+ 1, &ref_tree, &ref_root_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /* Mark s_inode's extent as refcounted. */
+ if (!(ext_flags & OCFS2_EXT_REFCOUNTED)) {
+ ret = ocfs2_add_refcount_flag(s_inode, &s_et,
+ &ref_tree->rf_ci,
+ ref_root_bh, spos,
+ p_cluster, num_clusters,
+ dealloc, NULL);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_unlock_refcount;
+ }
+ }
+
+ /* Map in the new extent. */
+ ext_flags |= OCFS2_EXT_REFCOUNTED;
+ ret = ocfs2_add_refcounted_extent(t_inode, &t_et,
+ &ref_tree->rf_ci,
+ ref_root_bh,
+ tpos, p_cluster,
+ num_clusters,
+ ext_flags,
+ dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_unlock_refcount;
+ }
+
+ ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
+ brelse(ref_root_bh);
+next_loop:
+ spos += num_clusters;
+ tpos += num_clusters;
+ }
+
+out:
+ return ret;
+out_unlock_refcount:
+ ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
+ brelse(ref_root_bh);
+ return ret;
+}
+
+/* Set up refcount tree and remap s_inode to t_inode. */
+static int ocfs2_reflink_remap_blocks(struct inode *s_inode,
+ struct buffer_head *s_bh,
+ loff_t pos_in,
+ struct inode *t_inode,
+ struct buffer_head *t_bh,
+ loff_t pos_out,
+ loff_t len)
+{
+ struct ocfs2_cached_dealloc_ctxt dealloc;
+ struct ocfs2_super *osb;
+ struct ocfs2_dinode *dis;
+ struct ocfs2_dinode *dit;
+ int ret;
+
+ osb = OCFS2_SB(s_inode->i_sb);
+ dis = (struct ocfs2_dinode *)s_bh->b_data;
+ dit = (struct ocfs2_dinode *)t_bh->b_data;
+ ocfs2_init_dealloc_ctxt(&dealloc);
+
+ /*
+ * If both inodes belong to two different refcount groups then
+ * forget it because we don't know how (or want) to go merging
+ * refcount trees.
+ */
+ ret = -EOPNOTSUPP;
+ if (ocfs2_is_refcount_inode(s_inode) &&
+ ocfs2_is_refcount_inode(t_inode) &&
+ le64_to_cpu(dis->i_refcount_loc) !+
le64_to_cpu(dit->i_refcount_loc))
+ goto out;
+
+ /* Neither inode has a refcount tree. Add one to s_inode. */
+ if (!ocfs2_is_refcount_inode(s_inode) &&
+ !ocfs2_is_refcount_inode(t_inode)) {
+ ret = ocfs2_create_refcount_tree(s_inode, s_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ /* Ensure that both inodes end up with the same refcount tree. */
+ if (!ocfs2_is_refcount_inode(s_inode)) {
+ ret = ocfs2_set_refcount_tree(s_inode, s_bh,
+ le64_to_cpu(dit->i_refcount_loc));
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+ if (!ocfs2_is_refcount_inode(t_inode)) {
+ ret = ocfs2_set_refcount_tree(t_inode, t_bh,
+ le64_to_cpu(dis->i_refcount_loc));
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ /*
+ * If we're reflinking the entire file and the source is inline
+ * data, just copy the contents.
+ */
+ if (pos_in == pos_out && pos_in == 0 && len ==
i_size_read(s_inode) &&
+ i_size_read(t_inode) <= len &&
+ (OCFS2_I(s_inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)) {
+ ret = ocfs2_duplicate_inline_data(s_inode, s_bh, t_inode, t_bh);
+ if (ret)
+ mlog_errno(ret);
+ goto out;
+ }
+
+ ret = ocfs2_reflink_remap_extent(s_inode, s_bh, pos_in, t_inode, t_bh,
+ pos_out, len, &dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+out:
+ if (ocfs2_dealloc_has_cluster(&dealloc)) {
+ ocfs2_schedule_truncate_log_flush(osb, 1);
+ ocfs2_run_deallocs(osb, &dealloc);
+ }
+
+ return ret;
+}
+
+/* Lock an inode and grab a bh pointing to the inode. */
+static int ocfs2_reflink_inodes_lock(struct inode *s_inode,
+ struct buffer_head **bh1,
+ struct inode *t_inode,
+ struct buffer_head **bh2)
+{
+ struct inode *inode1;
+ struct inode *inode2;
+ struct ocfs2_inode_info *oi1;
+ struct ocfs2_inode_info *oi2;
+ bool same_inode = (s_inode == t_inode);
+ int status;
+
+ /* First grab the VFS and rw locks. */
+ inode1 = s_inode;
+ inode2 = t_inode;
+ if (inode1->i_ino > inode2->i_ino)
+ swap(inode1, inode2);
+
+ inode_lock(inode1);
+ status = ocfs2_rw_lock(inode1, 1);
+ if (status) {
+ mlog_errno(status);
+ goto out_i1;
+ }
+ if (!same_inode) {
+ inode_lock_nested(inode2, I_MUTEX_CHILD);
+ status = ocfs2_rw_lock(inode2, 1);
+ if (status) {
+ mlog_errno(status);
+ goto out_i2;
+ }
+ }
+
+ /* Now go for the cluster locks */
+ oi1 = OCFS2_I(inode1);
+ oi2 = OCFS2_I(inode2);
+
+ trace_ocfs2_double_lock((unsigned long long)oi1->ip_blkno,
+ (unsigned long long)oi2->ip_blkno);
+
+ if (*bh1)
+ *bh1 = NULL;
+ if (*bh2)
+ *bh2 = NULL;
+
+ /* We always want to lock the one with the lower lockid first. */
+ if (oi1->ip_blkno > oi2->ip_blkno)
+ mlog_errno(-ENOLCK);
+
+ /* lock id1 */
+ status = ocfs2_inode_lock_nested(inode1, bh1, 1, OI_LS_REFLINK_TARGET);
+ if (status < 0) {
+ if (status != -ENOENT)
+ mlog_errno(status);
+ goto out_rw2;
+ }
+
+ /* lock id2 */
+ if (!same_inode) {
+ status = ocfs2_inode_lock_nested(inode2, bh2, 1,
+ OI_LS_REFLINK_TARGET);
+ if (status < 0) {
+ if (status != -ENOENT)
+ mlog_errno(status);
+ goto out_cl1;
+ }
+ } else
+ *bh2 = *bh1;
+
+ trace_ocfs2_double_lock_end(
+ (unsigned long long)OCFS2_I(inode1)->ip_blkno,
+ (unsigned long long)OCFS2_I(inode2)->ip_blkno);
+
+ return 0;
+
+out_cl1:
+ ocfs2_inode_unlock(inode1, 1);
+ brelse(*bh1);
+ *bh1 = NULL;
+out_rw2:
+ ocfs2_rw_unlock(inode2, 1);
+out_i2:
+ inode_unlock(inode2);
+ ocfs2_rw_unlock(inode1, 1);
+out_i1:
+ inode_unlock(inode1);
+ return status;
+}
+
+/* Unlock both inodes and release buffers. */
+static void ocfs2_reflink_inodes_unlock(struct inode *s_inode,
+ struct buffer_head *s_bh,
+ struct inode *t_inode,
+ struct buffer_head *t_bh)
+{
+ ocfs2_inode_unlock(s_inode, 1);
+ ocfs2_rw_unlock(s_inode, 1);
+ inode_unlock(s_inode);
+ brelse(s_bh);
+
+ if (s_inode == t_inode)
+ return;
+
+ ocfs2_inode_unlock(t_inode, 1);
+ ocfs2_rw_unlock(t_inode, 1);
+ inode_unlock(t_inode);
+ brelse(t_bh);
+}
+
+/*
+ * Read a page's worth of file data into the page cache. Return the page
+ * locked.
+ */
+static struct page *ocfs2_reflink_get_page(struct inode *inode,
+ loff_t offset)
+{
+ struct address_space *mapping;
+ struct page *page;
+ pgoff_t n;
+
+ n = offset >> PAGE_SHIFT;
+ mapping = inode->i_mapping;
+ page = read_mapping_page(mapping, n, NULL);
+ if (IS_ERR(page))
+ return page;
+ if (!PageUptodate(page)) {
+ put_page(page);
+ return ERR_PTR(-EIO);
+ }
+ lock_page(page);
+ return page;
+}
+
+/*
+ * Compare extents of two files to see if they are the same.
+ */
+static int ocfs2_reflink_compare_extents(struct inode *src,
+ loff_t srcoff,
+ struct inode *dest,
+ loff_t destoff,
+ loff_t len,
+ bool *is_same)
+{
+ loff_t src_poff;
+ loff_t dest_poff;
+ void *src_addr;
+ void *dest_addr;
+ struct page *src_page;
+ struct page *dest_page;
+ loff_t cmp_len;
+ bool same;
+ int error;
+
+ error = -EINVAL;
+ same = true;
+ while (len) {
+ src_poff = srcoff & (PAGE_SIZE - 1);
+ dest_poff = destoff & (PAGE_SIZE - 1);
+ cmp_len = min(PAGE_SIZE - src_poff,
+ PAGE_SIZE - dest_poff);
+ cmp_len = min(cmp_len, len);
+ if (cmp_len <= 0) {
+ mlog_errno(-EUCLEAN);
+ goto out_error;
+ }
+
+ src_page = ocfs2_reflink_get_page(src, srcoff);
+ if (IS_ERR(src_page)) {
+ error = PTR_ERR(src_page);
+ goto out_error;
+ }
+ dest_page = ocfs2_reflink_get_page(dest, destoff);
+ if (IS_ERR(dest_page)) {
+ error = PTR_ERR(dest_page);
+ unlock_page(src_page);
+ put_page(src_page);
+ goto out_error;
+ }
+ src_addr = kmap_atomic(src_page);
+ dest_addr = kmap_atomic(dest_page);
+
+ flush_dcache_page(src_page);
+ flush_dcache_page(dest_page);
+
+ if (memcmp(src_addr + src_poff, dest_addr + dest_poff, cmp_len))
+ same = false;
+
+ kunmap_atomic(dest_addr);
+ kunmap_atomic(src_addr);
+ unlock_page(dest_page);
+ unlock_page(src_page);
+ put_page(dest_page);
+ put_page(src_page);
+
+ if (!same)
+ break;
+
+ srcoff += cmp_len;
+ destoff += cmp_len;
+ len -= cmp_len;
+ }
+
+ *is_same = same;
+ return 0;
+
+out_error:
+ return error;
+}
+
+/* Link a range of blocks from one file to another. */
+int ocfs2_reflink_remap_range(struct file *file_in,
+ loff_t pos_in,
+ struct file *file_out,
+ loff_t pos_out,
+ u64 len,
+ bool is_dedupe)
+{
+ struct inode *inode_in = file_inode(file_in);
+ struct inode *inode_out = file_inode(file_out);
+ struct ocfs2_super *osb = OCFS2_SB(inode_in->i_sb);
+ struct buffer_head *in_bh = NULL, *out_bh = NULL;
+ loff_t bs = 1 << OCFS2_SB(inode_in->i_sb)->s_clustersize_bits;
+ bool same_inode = (inode_in == inode_out);
+ bool is_same = false;
+ loff_t isize;
+ ssize_t ret;
+ loff_t blen;
+
+ if (!ocfs2_refcount_tree(osb))
+ return -EOPNOTSUPP;
+ if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
+ return -EROFS;
+
+ /* Lock both files against IO */
+ ret = ocfs2_reflink_inodes_lock(inode_in, &in_bh, inode_out, &out_bh);
+ if (ret)
+ return ret;
+
+ ret = -EINVAL;
+ if ((OCFS2_I(inode_in)->ip_flags & OCFS2_INODE_SYSTEM_FILE) ||
+ (OCFS2_I(inode_out)->ip_flags & OCFS2_INODE_SYSTEM_FILE))
+ goto out_unlock;
+
+ /* Don't touch certain kinds of inodes */
+ ret = -EPERM;
+ if (IS_IMMUTABLE(inode_out))
+ goto out_unlock;
+
+ ret = -ETXTBSY;
+ if (IS_SWAPFILE(inode_in) || IS_SWAPFILE(inode_out))
+ goto out_unlock;
+
+ /* Don't reflink dirs, pipes, sockets... */
+ ret = -EISDIR;
+ if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode))
+ goto out_unlock;
+ ret = -EINVAL;
+ if (S_ISFIFO(inode_in->i_mode) || S_ISFIFO(inode_out->i_mode))
+ goto out_unlock;
+ if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode))
+ goto out_unlock;
+
+ /* Are we going all the way to the end? */
+ isize = i_size_read(inode_in);
+ if (isize == 0) {
+ ret = 0;
+ goto out_unlock;
+ }
+
+ if (len == 0)
+ len = isize - pos_in;
+
+ /* Ensure offsets don't wrap and the input is inside i_size */
+ if (pos_in + len < pos_in || pos_out + len < pos_out ||
+ pos_in + len > isize)
+ goto out_unlock;
+
+ /* Don't allow dedupe past EOF in the dest file */
+ if (is_dedupe) {
+ loff_t disize;
+
+ disize = i_size_read(inode_out);
+ if (pos_out >= disize || pos_out + len > disize)
+ goto out_unlock;
+ }
+
+ /* If we're linking to EOF, continue to the block boundary. */
+ if (pos_in + len == isize)
+ blen = ALIGN(isize, bs) - pos_in;
+ else
+ blen = len;
+
+ /* Only reflink if we're aligned to block boundaries */
+ if (!IS_ALIGNED(pos_in, bs) || !IS_ALIGNED(pos_in + blen, bs) ||
+ !IS_ALIGNED(pos_out, bs) || !IS_ALIGNED(pos_out + blen, bs))
+ goto out_unlock;
+
+ /* Don't allow overlapped reflink within the same file */
+ if (same_inode) {
+ if (pos_out + blen > pos_in && pos_out < pos_in + blen)
+ goto out_unlock;
+ }
+
+ /* Wait for the completion of any pending IOs on both files */
+ inode_dio_wait(inode_in);
+ if (!same_inode)
+ inode_dio_wait(inode_out);
+
+ ret = filemap_write_and_wait_range(inode_in->i_mapping,
+ pos_in, pos_in + len - 1);
+ if (ret)
+ goto out_unlock;
+
+ ret = filemap_write_and_wait_range(inode_out->i_mapping,
+ pos_out, pos_out + len - 1);
+ if (ret)
+ goto out_unlock;
+
+ /*
+ * Check that the extents are the same.
+ */
+ if (is_dedupe) {
+ ret = ocfs2_reflink_compare_extents(inode_in, pos_in,
+ inode_out, pos_out,
+ len, &is_same);
+ if (ret)
+ goto out_unlock;
+ if (!is_same) {
+ ret = -EBADE;
+ goto out_unlock;
+ }
+ }
+
+ /* Lock out changes to the allocation maps */
+ down_write(&OCFS2_I(inode_in)->ip_alloc_sem);
+ if (!same_inode)
+ down_write_nested(&OCFS2_I(inode_out)->ip_alloc_sem,
+ SINGLE_DEPTH_NESTING);
+
+ /*
+ * Invalidate the page cache so that we can clear any CoW mappings
+ * in the destination file.
+ */
+ truncate_inode_pages_range(&inode_out->i_data, pos_out,
+ PAGE_ALIGN(pos_out + len) - 1);
+
+ ret = ocfs2_reflink_remap_blocks(inode_in, in_bh, pos_in, inode_out,
+ out_bh, pos_out, len);
+
+ up_write(&OCFS2_I(inode_in)->ip_alloc_sem);
+ if (!same_inode)
+ up_write(&OCFS2_I(inode_out)->ip_alloc_sem);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_unlock;
+ }
+
+ /*
+ * Empty the extent map so that we may get the right extent
+ * record from the disk.
+ */
+ ocfs2_extent_map_trunc(inode_in, 0);
+ ocfs2_extent_map_trunc(inode_out, 0);
+
+ ret = ocfs2_reflink_update_dest(inode_out, out_bh, pos_out + len);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_unlock;
+ }
+
+ ocfs2_reflink_inodes_unlock(inode_in, in_bh, inode_out, out_bh);
+ return 0;
+
+out_unlock:
+ ocfs2_reflink_inodes_unlock(inode_in, in_bh, inode_out, out_bh);
+ return ret;
+}
diff --git a/fs/ocfs2/refcounttree.h b/fs/ocfs2/refcounttree.h
index 553edfb..c023e88 100644
--- a/fs/ocfs2/refcounttree.h
+++ b/fs/ocfs2/refcounttree.h
@@ -117,4 +117,11 @@ int ocfs2_reflink_ioctl(struct inode *inode,
const char __user *oldname,
const char __user *newname,
bool preserve);
+int ocfs2_reflink_remap_range(struct file *file_in,
+ loff_t pos_in,
+ struct file *file_out,
+ loff_t pos_out,
+ u64 len,
+ bool is_dedupe);
+
#endif /* OCFS2_REFCOUNTTREE_H */
Eric Ren
2016-Nov-11 05:49 UTC
[Ocfs2-devel] [PATCH 6/6] ocfs2: implement the VFS clone_range, copy_range, and dedupe_range features
Hi, A few issues obvious to me: On 11/10/2016 06:51 AM, Darrick J. Wong wrote:> Connect the new VFS clone_range, copy_range, and dedupe_range features > to the existing reflink capability of ocfs2. Compared to the existing > ocfs2 reflink ioctl We have to do things a little differently to support > the VFS semantics (we can clone subranges of a file but we don't clone > xattrs), but the VFS ioctls are more broadly supported.How can I test the new ocfs2 reflink (with this patch) manually? What commands should I use to do xxx_range things?> > Signed-off-by: Darrick J. Wong <darrick.wong at oracle.com> > --- > fs/ocfs2/file.c | 62 ++++- > fs/ocfs2/file.h | 3 > fs/ocfs2/refcounttree.c | 619 +++++++++++++++++++++++++++++++++++++++++++++++ > fs/ocfs2/refcounttree.h | 7 + > 4 files changed, 688 insertions(+), 3 deletions(-) > > > diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c > index 000c234..d5a022d 100644 > --- a/fs/ocfs2/file.c > +++ b/fs/ocfs2/file.c > @@ -1667,9 +1667,9 @@ static void ocfs2_calc_trunc_pos(struct inode *inode, > *done = ret; > } > > -static int ocfs2_remove_inode_range(struct inode *inode, > - struct buffer_head *di_bh, u64 byte_start, > - u64 byte_len) > +int ocfs2_remove_inode_range(struct inode *inode, > + struct buffer_head *di_bh, u64 byte_start, > + u64 byte_len) > { > int ret = 0, flags = 0, done = 0, i; > u32 trunc_start, trunc_len, trunc_end, trunc_cpos, phys_cpos; > @@ -2440,6 +2440,56 @@ static loff_t ocfs2_file_llseek(struct file *file, loff_t offset, int whence) > return offset; > } > > +static ssize_t ocfs2_file_copy_range(struct file *file_in, > + loff_t pos_in, > + struct file *file_out, > + loff_t pos_out, > + size_t len, > + unsigned int flags) > +{ > + int error; > + > + error = ocfs2_reflink_remap_range(file_in, pos_in, file_out, pos_out, > + len, false); > + if (error) > + return error; > + return len; > +} > + > +static int ocfs2_file_clone_range(struct file *file_in, > + loff_t pos_in, > + struct file *file_out, > + loff_t pos_out, > + u64 len) > +{ > + return ocfs2_reflink_remap_range(file_in, pos_in, file_out, pos_out, > + len, false); > +} > + > +#define OCFS2_MAX_DEDUPE_LEN (16 * 1024 * 1024) > +static ssize_t ocfs2_file_dedupe_range(struct file *src_file, > + u64 loff, > + u64 len, > + struct file *dst_file, > + u64 dst_loff) > +{ > + int error; > + > + /* > + * Limit the total length we will dedupe for each operation. > + * This is intended to bound the total time spent in this > + * ioctl to something sane. > + */ > + if (len > OCFS2_MAX_DEDUPE_LEN) > + len = OCFS2_MAX_DEDUPE_LEN; > + > + error = ocfs2_reflink_remap_range(src_file, loff, dst_file, dst_loff, > + len, true); > + if (error) > + return error; > + return len; > +} > + > const struct inode_operations ocfs2_file_iops = { > .setattr = ocfs2_setattr, > .getattr = ocfs2_getattr, > @@ -2479,6 +2529,9 @@ const struct file_operations ocfs2_fops = { > .splice_read = generic_file_splice_read, > .splice_write = iter_file_splice_write, > .fallocate = ocfs2_fallocate, > + .copy_file_range = ocfs2_file_copy_range, > + .clone_file_range = ocfs2_file_clone_range, > + .dedupe_file_range = ocfs2_file_dedupe_range, > }; > > const struct file_operations ocfs2_dops = { > @@ -2524,6 +2577,9 @@ const struct file_operations ocfs2_fops_no_plocks = { > .splice_read = generic_file_splice_read, > .splice_write = iter_file_splice_write, > .fallocate = ocfs2_fallocate, > + .copy_file_range = ocfs2_file_copy_range, > + .clone_file_range = ocfs2_file_clone_range, > + .dedupe_file_range = ocfs2_file_dedupe_range, > }; > > const struct file_operations ocfs2_dops_no_plocks = { > diff --git a/fs/ocfs2/file.h b/fs/ocfs2/file.h > index e8c62f2..897fd9a 100644 > --- a/fs/ocfs2/file.h > +++ b/fs/ocfs2/file.h > @@ -82,4 +82,7 @@ int ocfs2_change_file_space(struct file *file, unsigned int cmd, > > int ocfs2_check_range_for_refcount(struct inode *inode, loff_t pos, > size_t count); > +int ocfs2_remove_inode_range(struct inode *inode, > + struct buffer_head *di_bh, u64 byte_start, > + u64 byte_len); > #endif /* OCFS2_FILE_H */ > diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c > index d92b6c6..3e2198c 100644 > --- a/fs/ocfs2/refcounttree.c > +++ b/fs/ocfs2/refcounttree.c > @@ -34,6 +34,7 @@ > #include "xattr.h" > #include "namei.h" > #include "ocfs2_trace.h" > +#include "file.h" > > #include <linux/bio.h> > #include <linux/blkdev.h> > @@ -4447,3 +4448,621 @@ int ocfs2_reflink_ioctl(struct inode *inode, > > return error; > } > + > +/* Update destination inode size, if necessary. */ > +static int ocfs2_reflink_update_dest(struct inode *dest, > + struct buffer_head *d_bh, > + loff_t newlen) > +{ > + handle_t *handle; > + struct ocfs2_dinode *di = (struct ocfs2_dinode *)d_bh->b_data; > + int ret; > + > + if (newlen <= i_size_read(dest)) > + return 0; > + > + handle = ocfs2_start_trans(OCFS2_SB(dest->i_sb), > + OCFS2_INODE_UPDATE_CREDITS); > + if (IS_ERR(handle)) { > + ret = PTR_ERR(handle); > + mlog_errno(ret); > + return ret; > + } > + > + ret = ocfs2_journal_access_di(handle, INODE_CACHE(dest), d_bh, > + OCFS2_JOURNAL_ACCESS_WRITE); > + if (ret) { > + mlog_errno(ret); > + goto out_commit; > + } > + > + spin_lock(&OCFS2_I(dest)->ip_lock); > + if (newlen > i_size_read(dest)) { > + i_size_write(dest, newlen); > + di->i_size = newlen;di->i_size = cpu_to_le64(newlen);> + } > + spin_unlock(&OCFS2_I(dest)->ip_lock); > +Add ocfs2_update_inode_fsync_trans() here? Looks this function was introduced by you to improve efficiency. Just want to awake your memory about this, though I don't know about the details why it should be. Eric> + ocfs2_journal_dirty(handle, d_bh); > + > +out_commit: > + ocfs2_commit_trans(OCFS2_SB(dest->i_sb), handle); > + return ret; > +} > + > +/* Remap the range pos_in:len in s_inode to pos_out:len in t_inode. */ > +static int ocfs2_reflink_remap_extent(struct inode *s_inode, > + struct buffer_head *s_bh, > + loff_t pos_in, > + struct inode *t_inode, > + struct buffer_head *t_bh, > + loff_t pos_out, > + loff_t len, > + struct ocfs2_cached_dealloc_ctxt *dealloc) > +{ > + struct ocfs2_extent_tree s_et; > + struct ocfs2_extent_tree t_et; > + struct ocfs2_dinode *dis; > + struct buffer_head *ref_root_bh = NULL; > + struct ocfs2_refcount_tree *ref_tree; > + struct ocfs2_super *osb; > + loff_t pstart, plen; > + u32 p_cluster, num_clusters, slast, spos, tpos; > + unsigned int ext_flags; > + int ret = 0; > + > + osb = OCFS2_SB(s_inode->i_sb); > + dis = (struct ocfs2_dinode *)s_bh->b_data; > + ocfs2_init_dinode_extent_tree(&s_et, INODE_CACHE(s_inode), s_bh); > + ocfs2_init_dinode_extent_tree(&t_et, INODE_CACHE(t_inode), t_bh); > + > + spos = ocfs2_bytes_to_clusters(s_inode->i_sb, pos_in); > + tpos = ocfs2_bytes_to_clusters(t_inode->i_sb, pos_out); > + slast = ocfs2_clusters_for_bytes(s_inode->i_sb, pos_in + len); > + > + while (spos < slast) { > + if (fatal_signal_pending(current)) { > + ret = -EINTR; > + goto out; > + } > + > + /* Look up the extent. */ > + ret = ocfs2_get_clusters(s_inode, spos, &p_cluster, > + &num_clusters, &ext_flags); > + if (ret) { > + mlog_errno(ret); > + goto out; > + } > + > + num_clusters = min_t(u32, num_clusters, slast - spos); > + > + /* Punch out the dest range. */ > + pstart = ocfs2_clusters_to_bytes(t_inode->i_sb, tpos); > + plen = ocfs2_clusters_to_bytes(t_inode->i_sb, num_clusters); > + ret = ocfs2_remove_inode_range(t_inode, t_bh, pstart, plen); > + if (ret) { > + mlog_errno(ret); > + goto out; > + } > + > + if (p_cluster == 0) > + goto next_loop; > + > + /* Lock the refcount btree... */ > + ret = ocfs2_lock_refcount_tree(osb, > + le64_to_cpu(dis->i_refcount_loc), > + 1, &ref_tree, &ref_root_bh); > + if (ret) { > + mlog_errno(ret); > + goto out; > + } > + > + /* Mark s_inode's extent as refcounted. */ > + if (!(ext_flags & OCFS2_EXT_REFCOUNTED)) { > + ret = ocfs2_add_refcount_flag(s_inode, &s_et, > + &ref_tree->rf_ci, > + ref_root_bh, spos, > + p_cluster, num_clusters, > + dealloc, NULL); > + if (ret) { > + mlog_errno(ret); > + goto out_unlock_refcount; > + } > + } > + > + /* Map in the new extent. */ > + ext_flags |= OCFS2_EXT_REFCOUNTED; > + ret = ocfs2_add_refcounted_extent(t_inode, &t_et, > + &ref_tree->rf_ci, > + ref_root_bh, > + tpos, p_cluster, > + num_clusters, > + ext_flags, > + dealloc); > + if (ret) { > + mlog_errno(ret); > + goto out_unlock_refcount; > + } > + > + ocfs2_unlock_refcount_tree(osb, ref_tree, 1); > + brelse(ref_root_bh); > +next_loop: > + spos += num_clusters; > + tpos += num_clusters; > + } > + > +out: > + return ret; > +out_unlock_refcount: > + ocfs2_unlock_refcount_tree(osb, ref_tree, 1); > + brelse(ref_root_bh); > + return ret; > +} > + > +/* Set up refcount tree and remap s_inode to t_inode. */ > +static int ocfs2_reflink_remap_blocks(struct inode *s_inode, > + struct buffer_head *s_bh, > + loff_t pos_in, > + struct inode *t_inode, > + struct buffer_head *t_bh, > + loff_t pos_out, > + loff_t len) > +{ > + struct ocfs2_cached_dealloc_ctxt dealloc; > + struct ocfs2_super *osb; > + struct ocfs2_dinode *dis; > + struct ocfs2_dinode *dit; > + int ret; > + > + osb = OCFS2_SB(s_inode->i_sb); > + dis = (struct ocfs2_dinode *)s_bh->b_data; > + dit = (struct ocfs2_dinode *)t_bh->b_data; > + ocfs2_init_dealloc_ctxt(&dealloc); > + > + /* > + * If both inodes belong to two different refcount groups then > + * forget it because we don't know how (or want) to go merging > + * refcount trees. > + */ > + ret = -EOPNOTSUPP; > + if (ocfs2_is_refcount_inode(s_inode) && > + ocfs2_is_refcount_inode(t_inode) && > + le64_to_cpu(dis->i_refcount_loc) !> + le64_to_cpu(dit->i_refcount_loc)) > + goto out; > + > + /* Neither inode has a refcount tree. Add one to s_inode. */ > + if (!ocfs2_is_refcount_inode(s_inode) && > + !ocfs2_is_refcount_inode(t_inode)) { > + ret = ocfs2_create_refcount_tree(s_inode, s_bh); > + if (ret) { > + mlog_errno(ret); > + goto out; > + } > + } > + > + /* Ensure that both inodes end up with the same refcount tree. */ > + if (!ocfs2_is_refcount_inode(s_inode)) { > + ret = ocfs2_set_refcount_tree(s_inode, s_bh, > + le64_to_cpu(dit->i_refcount_loc)); > + if (ret) { > + mlog_errno(ret); > + goto out; > + } > + } > + if (!ocfs2_is_refcount_inode(t_inode)) { > + ret = ocfs2_set_refcount_tree(t_inode, t_bh, > + le64_to_cpu(dis->i_refcount_loc)); > + if (ret) { > + mlog_errno(ret); > + goto out; > + } > + } > + > + /* > + * If we're reflinking the entire file and the source is inline > + * data, just copy the contents. > + */ > + if (pos_in == pos_out && pos_in == 0 && len == i_size_read(s_inode) && > + i_size_read(t_inode) <= len && > + (OCFS2_I(s_inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)) { > + ret = ocfs2_duplicate_inline_data(s_inode, s_bh, t_inode, t_bh); > + if (ret) > + mlog_errno(ret); > + goto out; > + } > + > + ret = ocfs2_reflink_remap_extent(s_inode, s_bh, pos_in, t_inode, t_bh, > + pos_out, len, &dealloc); > + if (ret) { > + mlog_errno(ret); > + goto out; > + } > + > +out: > + if (ocfs2_dealloc_has_cluster(&dealloc)) { > + ocfs2_schedule_truncate_log_flush(osb, 1); > + ocfs2_run_deallocs(osb, &dealloc); > + } > + > + return ret; > +} > + > +/* Lock an inode and grab a bh pointing to the inode. */ > +static int ocfs2_reflink_inodes_lock(struct inode *s_inode, > + struct buffer_head **bh1, > + struct inode *t_inode, > + struct buffer_head **bh2) > +{ > + struct inode *inode1; > + struct inode *inode2; > + struct ocfs2_inode_info *oi1; > + struct ocfs2_inode_info *oi2; > + bool same_inode = (s_inode == t_inode); > + int status; > + > + /* First grab the VFS and rw locks. */ > + inode1 = s_inode; > + inode2 = t_inode; > + if (inode1->i_ino > inode2->i_ino) > + swap(inode1, inode2); > + > + inode_lock(inode1); > + status = ocfs2_rw_lock(inode1, 1); > + if (status) { > + mlog_errno(status); > + goto out_i1; > + } > + if (!same_inode) { > + inode_lock_nested(inode2, I_MUTEX_CHILD); > + status = ocfs2_rw_lock(inode2, 1); > + if (status) { > + mlog_errno(status); > + goto out_i2; > + } > + } > + > + /* Now go for the cluster locks */ > + oi1 = OCFS2_I(inode1); > + oi2 = OCFS2_I(inode2); > + > + trace_ocfs2_double_lock((unsigned long long)oi1->ip_blkno, > + (unsigned long long)oi2->ip_blkno); > + > + if (*bh1) > + *bh1 = NULL; > + if (*bh2) > + *bh2 = NULL; > + > + /* We always want to lock the one with the lower lockid first. */ > + if (oi1->ip_blkno > oi2->ip_blkno) > + mlog_errno(-ENOLCK); > + > + /* lock id1 */ > + status = ocfs2_inode_lock_nested(inode1, bh1, 1, OI_LS_REFLINK_TARGET); > + if (status < 0) { > + if (status != -ENOENT) > + mlog_errno(status); > + goto out_rw2; > + } > + > + /* lock id2 */ > + if (!same_inode) { > + status = ocfs2_inode_lock_nested(inode2, bh2, 1, > + OI_LS_REFLINK_TARGET); > + if (status < 0) { > + if (status != -ENOENT) > + mlog_errno(status); > + goto out_cl1; > + } > + } else > + *bh2 = *bh1; > + > + trace_ocfs2_double_lock_end( > + (unsigned long long)OCFS2_I(inode1)->ip_blkno, > + (unsigned long long)OCFS2_I(inode2)->ip_blkno); > + > + return 0; > + > +out_cl1: > + ocfs2_inode_unlock(inode1, 1); > + brelse(*bh1); > + *bh1 = NULL; > +out_rw2: > + ocfs2_rw_unlock(inode2, 1); > +out_i2: > + inode_unlock(inode2); > + ocfs2_rw_unlock(inode1, 1); > +out_i1: > + inode_unlock(inode1); > + return status; > +} > + > +/* Unlock both inodes and release buffers. */ > +static void ocfs2_reflink_inodes_unlock(struct inode *s_inode, > + struct buffer_head *s_bh, > + struct inode *t_inode, > + struct buffer_head *t_bh) > +{ > + ocfs2_inode_unlock(s_inode, 1); > + ocfs2_rw_unlock(s_inode, 1); > + inode_unlock(s_inode); > + brelse(s_bh); > + > + if (s_inode == t_inode) > + return; > + > + ocfs2_inode_unlock(t_inode, 1); > + ocfs2_rw_unlock(t_inode, 1); > + inode_unlock(t_inode); > + brelse(t_bh); > +} > + > +/* > + * Read a page's worth of file data into the page cache. Return the page > + * locked. > + */ > +static struct page *ocfs2_reflink_get_page(struct inode *inode, > + loff_t offset) > +{ > + struct address_space *mapping; > + struct page *page; > + pgoff_t n; > + > + n = offset >> PAGE_SHIFT; > + mapping = inode->i_mapping; > + page = read_mapping_page(mapping, n, NULL); > + if (IS_ERR(page)) > + return page; > + if (!PageUptodate(page)) { > + put_page(page); > + return ERR_PTR(-EIO); > + } > + lock_page(page); > + return page; > +} > + > +/* > + * Compare extents of two files to see if they are the same. > + */ > +static int ocfs2_reflink_compare_extents(struct inode *src, > + loff_t srcoff, > + struct inode *dest, > + loff_t destoff, > + loff_t len, > + bool *is_same) > +{ > + loff_t src_poff; > + loff_t dest_poff; > + void *src_addr; > + void *dest_addr; > + struct page *src_page; > + struct page *dest_page; > + loff_t cmp_len; > + bool same; > + int error; > + > + error = -EINVAL; > + same = true; > + while (len) { > + src_poff = srcoff & (PAGE_SIZE - 1); > + dest_poff = destoff & (PAGE_SIZE - 1); > + cmp_len = min(PAGE_SIZE - src_poff, > + PAGE_SIZE - dest_poff); > + cmp_len = min(cmp_len, len); > + if (cmp_len <= 0) { > + mlog_errno(-EUCLEAN); > + goto out_error; > + } > + > + src_page = ocfs2_reflink_get_page(src, srcoff); > + if (IS_ERR(src_page)) { > + error = PTR_ERR(src_page); > + goto out_error; > + } > + dest_page = ocfs2_reflink_get_page(dest, destoff); > + if (IS_ERR(dest_page)) { > + error = PTR_ERR(dest_page); > + unlock_page(src_page); > + put_page(src_page); > + goto out_error; > + } > + src_addr = kmap_atomic(src_page); > + dest_addr = kmap_atomic(dest_page); > + > + flush_dcache_page(src_page); > + flush_dcache_page(dest_page); > + > + if (memcmp(src_addr + src_poff, dest_addr + dest_poff, cmp_len)) > + same = false; > + > + kunmap_atomic(dest_addr); > + kunmap_atomic(src_addr); > + unlock_page(dest_page); > + unlock_page(src_page); > + put_page(dest_page); > + put_page(src_page); > + > + if (!same) > + break; > + > + srcoff += cmp_len; > + destoff += cmp_len; > + len -= cmp_len; > + } > + > + *is_same = same; > + return 0; > + > +out_error: > + return error; > +} > + > +/* Link a range of blocks from one file to another. */ > +int ocfs2_reflink_remap_range(struct file *file_in, > + loff_t pos_in, > + struct file *file_out, > + loff_t pos_out, > + u64 len, > + bool is_dedupe) > +{ > + struct inode *inode_in = file_inode(file_in); > + struct inode *inode_out = file_inode(file_out); > + struct ocfs2_super *osb = OCFS2_SB(inode_in->i_sb); > + struct buffer_head *in_bh = NULL, *out_bh = NULL; > + loff_t bs = 1 << OCFS2_SB(inode_in->i_sb)->s_clustersize_bits; > + bool same_inode = (inode_in == inode_out); > + bool is_same = false; > + loff_t isize; > + ssize_t ret; > + loff_t blen; > + > + if (!ocfs2_refcount_tree(osb)) > + return -EOPNOTSUPP; > + if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb)) > + return -EROFS; > + > + /* Lock both files against IO */ > + ret = ocfs2_reflink_inodes_lock(inode_in, &in_bh, inode_out, &out_bh); > + if (ret) > + return ret; > + > + ret = -EINVAL; > + if ((OCFS2_I(inode_in)->ip_flags & OCFS2_INODE_SYSTEM_FILE) || > + (OCFS2_I(inode_out)->ip_flags & OCFS2_INODE_SYSTEM_FILE)) > + goto out_unlock; > + > + /* Don't touch certain kinds of inodes */ > + ret = -EPERM; > + if (IS_IMMUTABLE(inode_out)) > + goto out_unlock; > + > + ret = -ETXTBSY; > + if (IS_SWAPFILE(inode_in) || IS_SWAPFILE(inode_out)) > + goto out_unlock; > + > + /* Don't reflink dirs, pipes, sockets... */ > + ret = -EISDIR; > + if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode)) > + goto out_unlock; > + ret = -EINVAL; > + if (S_ISFIFO(inode_in->i_mode) || S_ISFIFO(inode_out->i_mode)) > + goto out_unlock; > + if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode)) > + goto out_unlock; > + > + /* Are we going all the way to the end? */ > + isize = i_size_read(inode_in); > + if (isize == 0) { > + ret = 0; > + goto out_unlock; > + } > + > + if (len == 0) > + len = isize - pos_in; > + > + /* Ensure offsets don't wrap and the input is inside i_size */ > + if (pos_in + len < pos_in || pos_out + len < pos_out || > + pos_in + len > isize) > + goto out_unlock; > + > + /* Don't allow dedupe past EOF in the dest file */ > + if (is_dedupe) { > + loff_t disize; > + > + disize = i_size_read(inode_out); > + if (pos_out >= disize || pos_out + len > disize) > + goto out_unlock; > + } > + > + /* If we're linking to EOF, continue to the block boundary. */ > + if (pos_in + len == isize) > + blen = ALIGN(isize, bs) - pos_in; > + else > + blen = len; > + > + /* Only reflink if we're aligned to block boundaries */ > + if (!IS_ALIGNED(pos_in, bs) || !IS_ALIGNED(pos_in + blen, bs) || > + !IS_ALIGNED(pos_out, bs) || !IS_ALIGNED(pos_out + blen, bs)) > + goto out_unlock; > + > + /* Don't allow overlapped reflink within the same file */ > + if (same_inode) { > + if (pos_out + blen > pos_in && pos_out < pos_in + blen) > + goto out_unlock; > + } > + > + /* Wait for the completion of any pending IOs on both files */ > + inode_dio_wait(inode_in); > + if (!same_inode) > + inode_dio_wait(inode_out); > + > + ret = filemap_write_and_wait_range(inode_in->i_mapping, > + pos_in, pos_in + len - 1); > + if (ret) > + goto out_unlock; > + > + ret = filemap_write_and_wait_range(inode_out->i_mapping, > + pos_out, pos_out + len - 1); > + if (ret) > + goto out_unlock; > + > + /* > + * Check that the extents are the same. > + */ > + if (is_dedupe) { > + ret = ocfs2_reflink_compare_extents(inode_in, pos_in, > + inode_out, pos_out, > + len, &is_same); > + if (ret) > + goto out_unlock; > + if (!is_same) { > + ret = -EBADE; > + goto out_unlock; > + } > + } > + > + /* Lock out changes to the allocation maps */ > + down_write(&OCFS2_I(inode_in)->ip_alloc_sem); > + if (!same_inode) > + down_write_nested(&OCFS2_I(inode_out)->ip_alloc_sem, > + SINGLE_DEPTH_NESTING); > + > + /* > + * Invalidate the page cache so that we can clear any CoW mappings > + * in the destination file. > + */ > + truncate_inode_pages_range(&inode_out->i_data, pos_out, > + PAGE_ALIGN(pos_out + len) - 1); > + > + ret = ocfs2_reflink_remap_blocks(inode_in, in_bh, pos_in, inode_out, > + out_bh, pos_out, len); > + > + up_write(&OCFS2_I(inode_in)->ip_alloc_sem); > + if (!same_inode) > + up_write(&OCFS2_I(inode_out)->ip_alloc_sem); > + if (ret) { > + mlog_errno(ret); > + goto out_unlock; > + } > + > + /* > + * Empty the extent map so that we may get the right extent > + * record from the disk. > + */ > + ocfs2_extent_map_trunc(inode_in, 0); > + ocfs2_extent_map_trunc(inode_out, 0); > + > + ret = ocfs2_reflink_update_dest(inode_out, out_bh, pos_out + len); > + if (ret) { > + mlog_errno(ret); > + goto out_unlock; > + } > + > + ocfs2_reflink_inodes_unlock(inode_in, in_bh, inode_out, out_bh); > + return 0; > + > +out_unlock: > + ocfs2_reflink_inodes_unlock(inode_in, in_bh, inode_out, out_bh); > + return ret; > +} > diff --git a/fs/ocfs2/refcounttree.h b/fs/ocfs2/refcounttree.h > index 553edfb..c023e88 100644 > --- a/fs/ocfs2/refcounttree.h > +++ b/fs/ocfs2/refcounttree.h > @@ -117,4 +117,11 @@ int ocfs2_reflink_ioctl(struct inode *inode, > const char __user *oldname, > const char __user *newname, > bool preserve); > +int ocfs2_reflink_remap_range(struct file *file_in, > + loff_t pos_in, > + struct file *file_out, > + loff_t pos_out, > + u64 len, > + bool is_dedupe); > + > #endif /* OCFS2_REFCOUNTTREE_H */ > > > _______________________________________________ > Ocfs2-devel mailing list > Ocfs2-devel at oss.oracle.com > https://oss.oracle.com/mailman/listinfo/ocfs2-devel >
Darrick J. Wong
2016-Nov-11 14:54 UTC
[Ocfs2-devel] [PATCH v2 6/6] ocfs2: implement the VFS clone_range, copy_range, and dedupe_range features
Connect the new VFS clone_range, copy_range, and dedupe_range features
to the existing reflink capability of ocfs2. Compared to the existing
ocfs2 reflink ioctl We have to do things a little differently to support
the VFS semantics (we can clone subranges of a file but we don't clone
xattrs), but the VFS ioctls are more broadly supported.
Signed-off-by: Darrick J. Wong <darrick.wong at oracle.com>
---
v2: Convert inline data files to extents files before reflinking,
and fix i_blocks so that stat(2) output is correct. fsync the inoe
correctly.
---
fs/ocfs2/file.c | 62 ++++-
fs/ocfs2/file.h | 3
fs/ocfs2/refcounttree.c | 627 +++++++++++++++++++++++++++++++++++++++++++++++
fs/ocfs2/refcounttree.h | 7 +
4 files changed, 696 insertions(+), 3 deletions(-)
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index d261f3a..71aad0e 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -1667,9 +1667,9 @@ static void ocfs2_calc_trunc_pos(struct inode *inode,
*done = ret;
}
-static int ocfs2_remove_inode_range(struct inode *inode,
- struct buffer_head *di_bh, u64 byte_start,
- u64 byte_len)
+int ocfs2_remove_inode_range(struct inode *inode,
+ struct buffer_head *di_bh, u64 byte_start,
+ u64 byte_len)
{
int ret = 0, flags = 0, done = 0, i;
u32 trunc_start, trunc_len, trunc_end, trunc_cpos, phys_cpos;
@@ -2439,6 +2439,56 @@ static loff_t ocfs2_file_llseek(struct file *file, loff_t
offset, int whence)
return offset;
}
+static ssize_t ocfs2_file_copy_range(struct file *file_in,
+ loff_t pos_in,
+ struct file *file_out,
+ loff_t pos_out,
+ size_t len,
+ unsigned int flags)
+{
+ int error;
+
+ error = ocfs2_reflink_remap_range(file_in, pos_in, file_out, pos_out,
+ len, false);
+ if (error)
+ return error;
+ return len;
+}
+
+static int ocfs2_file_clone_range(struct file *file_in,
+ loff_t pos_in,
+ struct file *file_out,
+ loff_t pos_out,
+ u64 len)
+{
+ return ocfs2_reflink_remap_range(file_in, pos_in, file_out, pos_out,
+ len, false);
+}
+
+#define OCFS2_MAX_DEDUPE_LEN (16 * 1024 * 1024)
+static ssize_t ocfs2_file_dedupe_range(struct file *src_file,
+ u64 loff,
+ u64 len,
+ struct file *dst_file,
+ u64 dst_loff)
+{
+ int error;
+
+ /*
+ * Limit the total length we will dedupe for each operation.
+ * This is intended to bound the total time spent in this
+ * ioctl to something sane.
+ */
+ if (len > OCFS2_MAX_DEDUPE_LEN)
+ len = OCFS2_MAX_DEDUPE_LEN;
+
+ error = ocfs2_reflink_remap_range(src_file, loff, dst_file, dst_loff,
+ len, true);
+ if (error)
+ return error;
+ return len;
+}
+
const struct inode_operations ocfs2_file_iops = {
.setattr = ocfs2_setattr,
.getattr = ocfs2_getattr,
@@ -2478,6 +2528,9 @@ const struct file_operations ocfs2_fops = {
.splice_read = generic_file_splice_read,
.splice_write = iter_file_splice_write,
.fallocate = ocfs2_fallocate,
+ .copy_file_range = ocfs2_file_copy_range,
+ .clone_file_range = ocfs2_file_clone_range,
+ .dedupe_file_range = ocfs2_file_dedupe_range,
};
const struct file_operations ocfs2_dops = {
@@ -2523,6 +2576,9 @@ const struct file_operations ocfs2_fops_no_plocks = {
.splice_read = generic_file_splice_read,
.splice_write = iter_file_splice_write,
.fallocate = ocfs2_fallocate,
+ .copy_file_range = ocfs2_file_copy_range,
+ .clone_file_range = ocfs2_file_clone_range,
+ .dedupe_file_range = ocfs2_file_dedupe_range,
};
const struct file_operations ocfs2_dops_no_plocks = {
diff --git a/fs/ocfs2/file.h b/fs/ocfs2/file.h
index e8c62f2..897fd9a 100644
--- a/fs/ocfs2/file.h
+++ b/fs/ocfs2/file.h
@@ -82,4 +82,7 @@ int ocfs2_change_file_space(struct file *file, unsigned int
cmd,
int ocfs2_check_range_for_refcount(struct inode *inode, loff_t pos,
size_t count);
+int ocfs2_remove_inode_range(struct inode *inode,
+ struct buffer_head *di_bh, u64 byte_start,
+ u64 byte_len);
#endif /* OCFS2_FILE_H */
diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
index 6c98d56..be51540 100644
--- a/fs/ocfs2/refcounttree.c
+++ b/fs/ocfs2/refcounttree.c
@@ -34,6 +34,7 @@
#include "xattr.h"
#include "namei.h"
#include "ocfs2_trace.h"
+#include "file.h"
#include <linux/bio.h>
#include <linux/blkdev.h>
@@ -4441,3 +4442,629 @@ int ocfs2_reflink_ioctl(struct inode *inode,
return error;
}
+
+/* Update destination inode size, if necessary. */
+static int ocfs2_reflink_update_dest(struct inode *dest,
+ struct buffer_head *d_bh,
+ loff_t newlen)
+{
+ handle_t *handle;
+ int ret;
+
+ dest->i_blocks = ocfs2_inode_sector_count(dest);
+
+ if (newlen <= i_size_read(dest))
+ return 0;
+
+ handle = ocfs2_start_trans(OCFS2_SB(dest->i_sb),
+ OCFS2_INODE_UPDATE_CREDITS);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ return ret;
+ }
+
+ /* Extend i_size if needed. */
+ spin_lock(&OCFS2_I(dest)->ip_lock);
+ if (newlen > i_size_read(dest))
+ i_size_write(dest, newlen);
+ spin_unlock(&OCFS2_I(dest)->ip_lock);
+ dest->i_ctime = dest->i_mtime = current_time(dest);
+
+ ret = ocfs2_mark_inode_dirty(handle, dest, d_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_commit;
+ }
+
+out_commit:
+ ocfs2_commit_trans(OCFS2_SB(dest->i_sb), handle);
+ return ret;
+}
+
+/* Remap the range pos_in:len in s_inode to pos_out:len in t_inode. */
+static int ocfs2_reflink_remap_extent(struct inode *s_inode,
+ struct buffer_head *s_bh,
+ loff_t pos_in,
+ struct inode *t_inode,
+ struct buffer_head *t_bh,
+ loff_t pos_out,
+ loff_t len,
+ struct ocfs2_cached_dealloc_ctxt *dealloc)
+{
+ struct ocfs2_extent_tree s_et;
+ struct ocfs2_extent_tree t_et;
+ struct ocfs2_dinode *dis;
+ struct buffer_head *ref_root_bh = NULL;
+ struct ocfs2_refcount_tree *ref_tree;
+ struct ocfs2_super *osb;
+ loff_t pstart, plen;
+ u32 p_cluster, num_clusters, slast, spos, tpos;
+ unsigned int ext_flags;
+ int ret = 0;
+
+ osb = OCFS2_SB(s_inode->i_sb);
+ dis = (struct ocfs2_dinode *)s_bh->b_data;
+ ocfs2_init_dinode_extent_tree(&s_et, INODE_CACHE(s_inode), s_bh);
+ ocfs2_init_dinode_extent_tree(&t_et, INODE_CACHE(t_inode), t_bh);
+
+ spos = ocfs2_bytes_to_clusters(s_inode->i_sb, pos_in);
+ tpos = ocfs2_bytes_to_clusters(t_inode->i_sb, pos_out);
+ slast = ocfs2_clusters_for_bytes(s_inode->i_sb, pos_in + len);
+
+ while (spos < slast) {
+ if (fatal_signal_pending(current)) {
+ ret = -EINTR;
+ goto out;
+ }
+
+ /* Look up the extent. */
+ ret = ocfs2_get_clusters(s_inode, spos, &p_cluster,
+ &num_clusters, &ext_flags);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ num_clusters = min_t(u32, num_clusters, slast - spos);
+
+ /* Punch out the dest range. */
+ pstart = ocfs2_clusters_to_bytes(t_inode->i_sb, tpos);
+ plen = ocfs2_clusters_to_bytes(t_inode->i_sb, num_clusters);
+ ret = ocfs2_remove_inode_range(t_inode, t_bh, pstart, plen);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ if (p_cluster == 0)
+ goto next_loop;
+
+ /* Lock the refcount btree... */
+ ret = ocfs2_lock_refcount_tree(osb,
+ le64_to_cpu(dis->i_refcount_loc),
+ 1, &ref_tree, &ref_root_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /* Mark s_inode's extent as refcounted. */
+ if (!(ext_flags & OCFS2_EXT_REFCOUNTED)) {
+ ret = ocfs2_add_refcount_flag(s_inode, &s_et,
+ &ref_tree->rf_ci,
+ ref_root_bh, spos,
+ p_cluster, num_clusters,
+ dealloc, NULL);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_unlock_refcount;
+ }
+ }
+
+ /* Map in the new extent. */
+ ext_flags |= OCFS2_EXT_REFCOUNTED;
+ ret = ocfs2_add_refcounted_extent(t_inode, &t_et,
+ &ref_tree->rf_ci,
+ ref_root_bh,
+ tpos, p_cluster,
+ num_clusters,
+ ext_flags,
+ dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_unlock_refcount;
+ }
+
+ ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
+ brelse(ref_root_bh);
+next_loop:
+ spos += num_clusters;
+ tpos += num_clusters;
+ }
+
+out:
+ return ret;
+out_unlock_refcount:
+ ocfs2_unlock_refcount_tree(osb, ref_tree, 1);
+ brelse(ref_root_bh);
+ return ret;
+}
+
+/* Set up refcount tree and remap s_inode to t_inode. */
+static int ocfs2_reflink_remap_blocks(struct inode *s_inode,
+ struct buffer_head *s_bh,
+ loff_t pos_in,
+ struct inode *t_inode,
+ struct buffer_head *t_bh,
+ loff_t pos_out,
+ loff_t len)
+{
+ struct ocfs2_cached_dealloc_ctxt dealloc;
+ struct ocfs2_super *osb;
+ struct ocfs2_dinode *dis;
+ struct ocfs2_dinode *dit;
+ int ret;
+
+ osb = OCFS2_SB(s_inode->i_sb);
+ dis = (struct ocfs2_dinode *)s_bh->b_data;
+ dit = (struct ocfs2_dinode *)t_bh->b_data;
+ ocfs2_init_dealloc_ctxt(&dealloc);
+
+ /*
+ * If we're reflinking the entire file and the source is inline
+ * data, just copy the contents.
+ */
+ if (pos_in == pos_out && pos_in == 0 && len ==
i_size_read(s_inode) &&
+ i_size_read(t_inode) <= len &&
+ (OCFS2_I(s_inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)) {
+ ret = ocfs2_duplicate_inline_data(s_inode, s_bh, t_inode, t_bh);
+ if (ret)
+ mlog_errno(ret);
+ goto out;
+ }
+
+ /*
+ * If both inodes belong to two different refcount groups then
+ * forget it because we don't know how (or want) to go merging
+ * refcount trees.
+ */
+ ret = -EOPNOTSUPP;
+ if (ocfs2_is_refcount_inode(s_inode) &&
+ ocfs2_is_refcount_inode(t_inode) &&
+ le64_to_cpu(dis->i_refcount_loc) !+
le64_to_cpu(dit->i_refcount_loc))
+ goto out;
+
+ /* Neither inode has a refcount tree. Add one to s_inode. */
+ if (!ocfs2_is_refcount_inode(s_inode) &&
+ !ocfs2_is_refcount_inode(t_inode)) {
+ ret = ocfs2_create_refcount_tree(s_inode, s_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ /* Ensure that both inodes end up with the same refcount tree. */
+ if (!ocfs2_is_refcount_inode(s_inode)) {
+ ret = ocfs2_set_refcount_tree(s_inode, s_bh,
+ le64_to_cpu(dit->i_refcount_loc));
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+ if (!ocfs2_is_refcount_inode(t_inode)) {
+ ret = ocfs2_set_refcount_tree(t_inode, t_bh,
+ le64_to_cpu(dis->i_refcount_loc));
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ /* Turn off inline data in the dest file. */
+ if (OCFS2_I(t_inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL) {
+ ret = ocfs2_convert_inline_data_to_extents(t_inode, t_bh);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+ }
+
+ /* Actually remap extents now. */
+ ret = ocfs2_reflink_remap_extent(s_inode, s_bh, pos_in, t_inode, t_bh,
+ pos_out, len, &dealloc);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+out:
+ if (ocfs2_dealloc_has_cluster(&dealloc)) {
+ ocfs2_schedule_truncate_log_flush(osb, 1);
+ ocfs2_run_deallocs(osb, &dealloc);
+ }
+
+ return ret;
+}
+
+/* Lock an inode and grab a bh pointing to the inode. */
+static int ocfs2_reflink_inodes_lock(struct inode *s_inode,
+ struct buffer_head **bh1,
+ struct inode *t_inode,
+ struct buffer_head **bh2)
+{
+ struct inode *inode1;
+ struct inode *inode2;
+ struct ocfs2_inode_info *oi1;
+ struct ocfs2_inode_info *oi2;
+ bool same_inode = (s_inode == t_inode);
+ int status;
+
+ /* First grab the VFS and rw locks. */
+ inode1 = s_inode;
+ inode2 = t_inode;
+ if (inode1->i_ino > inode2->i_ino)
+ swap(inode1, inode2);
+
+ inode_lock(inode1);
+ status = ocfs2_rw_lock(inode1, 1);
+ if (status) {
+ mlog_errno(status);
+ goto out_i1;
+ }
+ if (!same_inode) {
+ inode_lock_nested(inode2, I_MUTEX_CHILD);
+ status = ocfs2_rw_lock(inode2, 1);
+ if (status) {
+ mlog_errno(status);
+ goto out_i2;
+ }
+ }
+
+ /* Now go for the cluster locks */
+ oi1 = OCFS2_I(inode1);
+ oi2 = OCFS2_I(inode2);
+
+ trace_ocfs2_double_lock((unsigned long long)oi1->ip_blkno,
+ (unsigned long long)oi2->ip_blkno);
+
+ if (*bh1)
+ *bh1 = NULL;
+ if (*bh2)
+ *bh2 = NULL;
+
+ /* We always want to lock the one with the lower lockid first. */
+ if (oi1->ip_blkno > oi2->ip_blkno)
+ mlog_errno(-ENOLCK);
+
+ /* lock id1 */
+ status = ocfs2_inode_lock_nested(inode1, bh1, 1, OI_LS_REFLINK_TARGET);
+ if (status < 0) {
+ if (status != -ENOENT)
+ mlog_errno(status);
+ goto out_rw2;
+ }
+
+ /* lock id2 */
+ if (!same_inode) {
+ status = ocfs2_inode_lock_nested(inode2, bh2, 1,
+ OI_LS_REFLINK_TARGET);
+ if (status < 0) {
+ if (status != -ENOENT)
+ mlog_errno(status);
+ goto out_cl1;
+ }
+ } else
+ *bh2 = *bh1;
+
+ trace_ocfs2_double_lock_end(
+ (unsigned long long)OCFS2_I(inode1)->ip_blkno,
+ (unsigned long long)OCFS2_I(inode2)->ip_blkno);
+
+ return 0;
+
+out_cl1:
+ ocfs2_inode_unlock(inode1, 1);
+ brelse(*bh1);
+ *bh1 = NULL;
+out_rw2:
+ ocfs2_rw_unlock(inode2, 1);
+out_i2:
+ inode_unlock(inode2);
+ ocfs2_rw_unlock(inode1, 1);
+out_i1:
+ inode_unlock(inode1);
+ return status;
+}
+
+/* Unlock both inodes and release buffers. */
+static void ocfs2_reflink_inodes_unlock(struct inode *s_inode,
+ struct buffer_head *s_bh,
+ struct inode *t_inode,
+ struct buffer_head *t_bh)
+{
+ ocfs2_inode_unlock(s_inode, 1);
+ ocfs2_rw_unlock(s_inode, 1);
+ inode_unlock(s_inode);
+ brelse(s_bh);
+
+ if (s_inode == t_inode)
+ return;
+
+ ocfs2_inode_unlock(t_inode, 1);
+ ocfs2_rw_unlock(t_inode, 1);
+ inode_unlock(t_inode);
+ brelse(t_bh);
+}
+
+/*
+ * Read a page's worth of file data into the page cache. Return the page
+ * locked.
+ */
+static struct page *ocfs2_reflink_get_page(struct inode *inode,
+ loff_t offset)
+{
+ struct address_space *mapping;
+ struct page *page;
+ pgoff_t n;
+
+ n = offset >> PAGE_SHIFT;
+ mapping = inode->i_mapping;
+ page = read_mapping_page(mapping, n, NULL);
+ if (IS_ERR(page))
+ return page;
+ if (!PageUptodate(page)) {
+ put_page(page);
+ return ERR_PTR(-EIO);
+ }
+ lock_page(page);
+ return page;
+}
+
+/*
+ * Compare extents of two files to see if they are the same.
+ */
+static int ocfs2_reflink_compare_extents(struct inode *src,
+ loff_t srcoff,
+ struct inode *dest,
+ loff_t destoff,
+ loff_t len,
+ bool *is_same)
+{
+ loff_t src_poff;
+ loff_t dest_poff;
+ void *src_addr;
+ void *dest_addr;
+ struct page *src_page;
+ struct page *dest_page;
+ loff_t cmp_len;
+ bool same;
+ int error;
+
+ error = -EINVAL;
+ same = true;
+ while (len) {
+ src_poff = srcoff & (PAGE_SIZE - 1);
+ dest_poff = destoff & (PAGE_SIZE - 1);
+ cmp_len = min(PAGE_SIZE - src_poff,
+ PAGE_SIZE - dest_poff);
+ cmp_len = min(cmp_len, len);
+ if (cmp_len <= 0) {
+ mlog_errno(-EUCLEAN);
+ goto out_error;
+ }
+
+ src_page = ocfs2_reflink_get_page(src, srcoff);
+ if (IS_ERR(src_page)) {
+ error = PTR_ERR(src_page);
+ goto out_error;
+ }
+ dest_page = ocfs2_reflink_get_page(dest, destoff);
+ if (IS_ERR(dest_page)) {
+ error = PTR_ERR(dest_page);
+ unlock_page(src_page);
+ put_page(src_page);
+ goto out_error;
+ }
+ src_addr = kmap_atomic(src_page);
+ dest_addr = kmap_atomic(dest_page);
+
+ flush_dcache_page(src_page);
+ flush_dcache_page(dest_page);
+
+ if (memcmp(src_addr + src_poff, dest_addr + dest_poff, cmp_len))
+ same = false;
+
+ kunmap_atomic(dest_addr);
+ kunmap_atomic(src_addr);
+ unlock_page(dest_page);
+ unlock_page(src_page);
+ put_page(dest_page);
+ put_page(src_page);
+
+ if (!same)
+ break;
+
+ srcoff += cmp_len;
+ destoff += cmp_len;
+ len -= cmp_len;
+ }
+
+ *is_same = same;
+ return 0;
+
+out_error:
+ return error;
+}
+
+/* Link a range of blocks from one file to another. */
+int ocfs2_reflink_remap_range(struct file *file_in,
+ loff_t pos_in,
+ struct file *file_out,
+ loff_t pos_out,
+ u64 len,
+ bool is_dedupe)
+{
+ struct inode *inode_in = file_inode(file_in);
+ struct inode *inode_out = file_inode(file_out);
+ struct ocfs2_super *osb = OCFS2_SB(inode_in->i_sb);
+ struct buffer_head *in_bh = NULL, *out_bh = NULL;
+ loff_t bs = 1 << OCFS2_SB(inode_in->i_sb)->s_clustersize_bits;
+ bool same_inode = (inode_in == inode_out);
+ bool is_same = false;
+ loff_t isize;
+ ssize_t ret;
+ loff_t blen;
+
+ if (!ocfs2_refcount_tree(osb))
+ return -EOPNOTSUPP;
+ if (ocfs2_is_hard_readonly(osb) || ocfs2_is_soft_readonly(osb))
+ return -EROFS;
+
+ /* Lock both files against IO */
+ ret = ocfs2_reflink_inodes_lock(inode_in, &in_bh, inode_out, &out_bh);
+ if (ret)
+ return ret;
+
+ ret = -EINVAL;
+ if ((OCFS2_I(inode_in)->ip_flags & OCFS2_INODE_SYSTEM_FILE) ||
+ (OCFS2_I(inode_out)->ip_flags & OCFS2_INODE_SYSTEM_FILE))
+ goto out_unlock;
+
+ /* Don't touch certain kinds of inodes */
+ ret = -EPERM;
+ if (IS_IMMUTABLE(inode_out))
+ goto out_unlock;
+
+ ret = -ETXTBSY;
+ if (IS_SWAPFILE(inode_in) || IS_SWAPFILE(inode_out))
+ goto out_unlock;
+
+ /* Don't reflink dirs, pipes, sockets... */
+ ret = -EISDIR;
+ if (S_ISDIR(inode_in->i_mode) || S_ISDIR(inode_out->i_mode))
+ goto out_unlock;
+ ret = -EINVAL;
+ if (S_ISFIFO(inode_in->i_mode) || S_ISFIFO(inode_out->i_mode))
+ goto out_unlock;
+ if (!S_ISREG(inode_in->i_mode) || !S_ISREG(inode_out->i_mode))
+ goto out_unlock;
+
+ /* Are we going all the way to the end? */
+ isize = i_size_read(inode_in);
+ if (isize == 0) {
+ ret = 0;
+ goto out_unlock;
+ }
+
+ if (len == 0)
+ len = isize - pos_in;
+
+ /* Ensure offsets don't wrap and the input is inside i_size */
+ if (pos_in + len < pos_in || pos_out + len < pos_out ||
+ pos_in + len > isize)
+ goto out_unlock;
+
+ /* Don't allow dedupe past EOF in the dest file */
+ if (is_dedupe) {
+ loff_t disize;
+
+ disize = i_size_read(inode_out);
+ if (pos_out >= disize || pos_out + len > disize)
+ goto out_unlock;
+ }
+
+ /* If we're linking to EOF, continue to the block boundary. */
+ if (pos_in + len == isize)
+ blen = ALIGN(isize, bs) - pos_in;
+ else
+ blen = len;
+
+ /* Only reflink if we're aligned to block boundaries */
+ if (!IS_ALIGNED(pos_in, bs) || !IS_ALIGNED(pos_in + blen, bs) ||
+ !IS_ALIGNED(pos_out, bs) || !IS_ALIGNED(pos_out + blen, bs))
+ goto out_unlock;
+
+ /* Don't allow overlapped reflink within the same file */
+ if (same_inode) {
+ if (pos_out + blen > pos_in && pos_out < pos_in + blen)
+ goto out_unlock;
+ }
+
+ /* Wait for the completion of any pending IOs on both files */
+ inode_dio_wait(inode_in);
+ if (!same_inode)
+ inode_dio_wait(inode_out);
+
+ ret = filemap_write_and_wait_range(inode_in->i_mapping,
+ pos_in, pos_in + len - 1);
+ if (ret)
+ goto out_unlock;
+
+ ret = filemap_write_and_wait_range(inode_out->i_mapping,
+ pos_out, pos_out + len - 1);
+ if (ret)
+ goto out_unlock;
+
+ /*
+ * Check that the extents are the same.
+ */
+ if (is_dedupe) {
+ ret = ocfs2_reflink_compare_extents(inode_in, pos_in,
+ inode_out, pos_out,
+ len, &is_same);
+ if (ret)
+ goto out_unlock;
+ if (!is_same) {
+ ret = -EBADE;
+ goto out_unlock;
+ }
+ }
+
+ /* Lock out changes to the allocation maps */
+ down_write(&OCFS2_I(inode_in)->ip_alloc_sem);
+ if (!same_inode)
+ down_write_nested(&OCFS2_I(inode_out)->ip_alloc_sem,
+ SINGLE_DEPTH_NESTING);
+
+ /*
+ * Invalidate the page cache so that we can clear any CoW mappings
+ * in the destination file.
+ */
+ truncate_inode_pages_range(&inode_out->i_data, pos_out,
+ PAGE_ALIGN(pos_out + len) - 1);
+
+ ret = ocfs2_reflink_remap_blocks(inode_in, in_bh, pos_in, inode_out,
+ out_bh, pos_out, len);
+
+ up_write(&OCFS2_I(inode_in)->ip_alloc_sem);
+ if (!same_inode)
+ up_write(&OCFS2_I(inode_out)->ip_alloc_sem);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_unlock;
+ }
+
+ /*
+ * Empty the extent map so that we may get the right extent
+ * record from the disk.
+ */
+ ocfs2_extent_map_trunc(inode_in, 0);
+ ocfs2_extent_map_trunc(inode_out, 0);
+
+ ret = ocfs2_reflink_update_dest(inode_out, out_bh, pos_out + len);
+ if (ret) {
+ mlog_errno(ret);
+ goto out_unlock;
+ }
+
+ ocfs2_reflink_inodes_unlock(inode_in, in_bh, inode_out, out_bh);
+ return 0;
+
+out_unlock:
+ ocfs2_reflink_inodes_unlock(inode_in, in_bh, inode_out, out_bh);
+ return ret;
+}
diff --git a/fs/ocfs2/refcounttree.h b/fs/ocfs2/refcounttree.h
index 6422bbc..4af55bf 100644
--- a/fs/ocfs2/refcounttree.h
+++ b/fs/ocfs2/refcounttree.h
@@ -115,4 +115,11 @@ int ocfs2_reflink_ioctl(struct inode *inode,
const char __user *oldname,
const char __user *newname,
bool preserve);
+int ocfs2_reflink_remap_range(struct file *file_in,
+ loff_t pos_in,
+ struct file *file_out,
+ loff_t pos_out,
+ u64 len,
+ bool is_dedupe);
+
#endif /* OCFS2_REFCOUNTTREE_H */