NOVA leverages the kernel's DAX mechanisms for mmap and file data access. Nova
maintains a red-black tree in DRAM (nova_inode_info_header.vma_tree) to track
which portions of a file have been mapped.
Signed-off-by: Steven Swanson <swan...@cs.ucsd.edu>
---
fs/nova/dax.c | 1346 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 1346 insertions(+)
create mode 100644 fs/nova/dax.c
diff --git a/fs/nova/dax.c b/fs/nova/dax.c
new file mode 100644
index 000000000000..871b10f1889c
--- /dev/null
+++ b/fs/nova/dax.c
@@ -0,0 +1,1346 @@
+/*
+ * BRIEF DESCRIPTION
+ *
+ * DAX file operations.
+ *
+ * Copyright 2015-2016 Regents of the University of California,
+ * UCSD Non-Volatile Systems Lab, Andiry Xu <jix...@cs.ucsd.edu>
+ * Copyright 2012-2013 Intel Corporation
+ * Copyright 2009-2011 Marco Stornelli <marco.storne...@gmail.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/module.h>
+#include <linux/buffer_head.h>
+#include <linux/cpufeature.h>
+#include <asm/pgtable.h>
+#include <linux/version.h>
+#include "nova.h"
+#include "inode.h"
+
+
+
+static inline int nova_copy_partial_block(struct super_block *sb,
+ struct nova_inode_info_header *sih,
+ struct nova_file_write_entry *entry, unsigned long index,
+ size_t offset, size_t length, void *kmem)
+{
+ void *ptr;
+ int rc = 0;
+ unsigned long nvmm;
+
+ nvmm = get_nvmm(sb, sih, entry, index);
+ ptr = nova_get_block(sb, (nvmm << PAGE_SHIFT));
+
+ if (ptr != NULL) {
+ if (support_clwb)
+ rc = memcpy_mcsafe(kmem + offset, ptr + offset,
+ length);
+ else
+ memcpy_to_pmem_nocache(kmem + offset, ptr + offset,
+ length);
+ }
+
+ /* TODO: If rc < 0, go to MCE data recovery. */
+ return rc;
+}
+
+static inline int nova_handle_partial_block(struct super_block *sb,
+ struct nova_inode_info_header *sih,
+ struct nova_file_write_entry *entry, unsigned long index,
+ size_t offset, size_t length, void *kmem)
+{
+ struct nova_sb_info *sbi = NOVA_SB(sb);
+ struct nova_file_write_entry *entryc, entry_copy;
+
+ nova_memunlock_block(sb, kmem);
+ if (entry == NULL) {
+ /* Fill zero */
+ if (support_clwb)
+ memset(kmem + offset, 0, length);
+ else
+ memcpy_to_pmem_nocache(kmem + offset,
+ sbi->zeroed_page, length);
+ } else {
+ /* Copy from original block */
+ if (metadata_csum == 0)
+ entryc = entry;
+ else {
+ entryc = &entry_copy;
+ if (!nova_verify_entry_csum(sb, entry, entryc))
+ return -EIO;
+ }
+
+ nova_copy_partial_block(sb, sih, entryc, index,
+ offset, length, kmem);
+
+ }
+ nova_memlock_block(sb, kmem);
+ if (support_clwb)
+ nova_flush_buffer(kmem + offset, length, 0);
+ return 0;
+}
+
+/*
+ * Fill the new start/end block from original blocks.
+ * Do nothing if fully covered; copy if original blocks present;
+ * Fill zero otherwise.
+ */
+int nova_handle_head_tail_blocks(struct super_block *sb,
+ struct inode *inode, loff_t pos, size_t count, void *kmem)
+{
+ struct nova_inode_info *si = NOVA_I(inode);
+ struct nova_inode_info_header *sih = &si->header;
+ size_t offset, eblk_offset;
+ unsigned long start_blk, end_blk, num_blocks;
+ struct nova_file_write_entry *entry;
+ timing_t partial_time;
+ int ret = 0;
+
+ NOVA_START_TIMING(partial_block_t, partial_time);
+ offset = pos & (sb->s_blocksize - 1);
+ num_blocks = ((count + offset - 1) >> sb->s_blocksize_bits) + 1;
+ /* offset in the actual block size block */
+ offset = pos & (nova_inode_blk_size(sih) - 1);
+ start_blk = pos >> sb->s_blocksize_bits;
+ end_blk = start_blk + num_blocks - 1;
+
+ nova_dbg_verbose("%s: %lu blocks\n", __func__, num_blocks);
+ /* We avoid zeroing the alloc'd range, which is going to be overwritten
+ * by this system call anyway
+ */
+ nova_dbg_verbose("%s: start offset %lu start blk %lu %p\n", __func__,
+ offset, start_blk, kmem);
+ if (offset != 0) {
+ entry = nova_get_write_entry(sb, sih, start_blk);
+ ret = nova_handle_partial_block(sb, sih, entry,
+ start_blk, 0, offset, kmem);
+ if (ret < 0)
+ return ret;
+ }
+
+ kmem = (void *)((char *)kmem +
+ ((num_blocks - 1) << sb->s_blocksize_bits));
+ eblk_offset = (pos + count) & (nova_inode_blk_size(sih) - 1);
+ nova_dbg_verbose("%s: end offset %lu, end blk %lu %p\n", __func__,
+ eblk_offset, end_blk, kmem);
+ if (eblk_offset != 0) {
+ entry = nova_get_write_entry(sb, sih, end_blk);
+
+ ret = nova_handle_partial_block(sb, sih, entry, end_blk,
+ eblk_offset,
+ sb->s_blocksize - eblk_offset,
+ kmem);
+ if (ret < 0)
+ return ret;
+ }
+ NOVA_END_TIMING(partial_block_t, partial_time);
+
+ return ret;
+}
+
+int nova_reassign_file_tree(struct super_block *sb,
+ struct nova_inode_info_header *sih, u64 begin_tail)
+{
+ void *addr;
+ struct nova_file_write_entry *entry;
+ struct nova_file_write_entry *entryc, entry_copy;
+ u64 curr_p = begin_tail;
+ size_t entry_size = sizeof(struct nova_file_write_entry);
+
+ entryc = (metadata_csum == 0) ? entry : &entry_copy;
+
+ while (curr_p && curr_p != sih->log_tail) {
+ if (is_last_entry(curr_p, entry_size))
+ curr_p = next_log_page(sb, curr_p);
+
+ if (curr_p == 0) {
+ nova_err(sb, "%s: File inode %lu log is NULL!\n",
+ __func__, sih->ino);
+ return -EINVAL;
+ }
+
+ addr = (void *) nova_get_block(sb, curr_p);
+ entry = (struct nova_file_write_entry *) addr;
+
+ if (metadata_csum == 0)
+ entryc = entry;
+ else if (!nova_verify_entry_csum(sb, entry, entryc))
+ return -EIO;
+
+ if (nova_get_entry_type(entryc) != FILE_WRITE) {
+ nova_dbg("%s: entry type is not write? %d\n",
+ __func__, nova_get_entry_type(entry));
+ curr_p += entry_size;
+ continue;
+ }
+
+ nova_assign_write_entry(sb, sih, entry, entryc, true);
+ curr_p += entry_size;
+ }
+
+ return 0;
+}
+
+int nova_cleanup_incomplete_write(struct super_block *sb,
+ struct nova_inode_info_header *sih, unsigned long blocknr,
+ int allocated, u64 begin_tail, u64 end_tail)
+{
+ void *addr;
+ struct nova_file_write_entry *entry;
+ struct nova_file_write_entry *entryc, entry_copy;
+ u64 curr_p = begin_tail;
+ size_t entry_size = sizeof(struct nova_file_write_entry);
+
+ if (blocknr > 0 && allocated > 0)
+ nova_free_data_blocks(sb, sih, blocknr, allocated);
+
+ if (begin_tail == 0 || end_tail == 0)
+ return 0;
+
+ entryc = (metadata_csum == 0) ? entry : &entry_copy;
+
+ while (curr_p != end_tail) {
+ if (is_last_entry(curr_p, entry_size))
+ curr_p = next_log_page(sb, curr_p);
+
+ if (curr_p == 0) {
+ nova_err(sb, "%s: File inode %lu log is NULL!\n",
+ __func__, sih->ino);
+ return -EINVAL;
+ }
+
+ addr = (void *) nova_get_block(sb, curr_p);
+ entry = (struct nova_file_write_entry *) addr;
+
+ if (metadata_csum == 0)
+ entryc = entry;
+ else {
+ /* skip entry check here as the entry checksum may not
+ * be updated when this is called
+ */
+ if (memcpy_mcsafe(entryc, entry,
+ sizeof(struct nova_file_write_entry)))
+ return -EIO;
+ }
+
+ if (nova_get_entry_type(entryc) != FILE_WRITE) {
+ nova_dbg("%s: entry type is not write? %d\n",
+ __func__, nova_get_entry_type(entry));
+ curr_p += entry_size;
+ continue;
+ }
+
+ blocknr = entryc->block >> PAGE_SHIFT;
+ nova_free_data_blocks(sb, sih, blocknr, entryc->num_pages);
+ curr_p += entry_size;
+ }
+
+ return 0;
+}
+
+void nova_init_file_write_entry(struct super_block *sb,
+ struct nova_inode_info_header *sih, struct nova_file_write_entry *entry,
+ u64 epoch_id, u64 pgoff, int num_pages, u64 blocknr, u32 time,
+ u64 file_size)
+{
+ memset(entry, 0, sizeof(struct nova_file_write_entry));
+ entry->entry_type = FILE_WRITE;
+ entry->reassigned = 0;
+ entry->updating = 0;
+ entry->epoch_id = epoch_id;
+ entry->trans_id = sih->trans_id;
+ entry->pgoff = cpu_to_le64(pgoff);
+ entry->num_pages = cpu_to_le32(num_pages);
+ entry->invalid_pages = 0;
+ entry->block = cpu_to_le64(nova_get_block_off(sb, blocknr,
+ sih->i_blk_type));
+ entry->mtime = cpu_to_le32(time);
+
+ entry->size = file_size;
+}
+
+int nova_protect_file_data(struct super_block *sb, struct inode *inode,
+ loff_t pos, size_t count, const char __user *buf, unsigned long blocknr,
+ bool inplace)
+{
+ struct nova_inode_info *si = NOVA_I(inode);
+ struct nova_inode_info_header *sih = &si->header;
+ size_t offset, eblk_offset, bytes, left;
+ unsigned long start_blk, end_blk, num_blocks, nvmm, nvmmoff;
+ unsigned long blocksize = sb->s_blocksize;
+ unsigned int blocksize_bits = sb->s_blocksize_bits;
+ u8 *blockbuf, *blockptr;
+ struct nova_file_write_entry *entry;
+ struct nova_file_write_entry *entryc, entry_copy;
+ bool mapped, nvmm_ok;
+ int ret = 0;
+ timing_t protect_file_data_time, memcpy_time;
+
+ NOVA_START_TIMING(protect_file_data_t, protect_file_data_time);
+
+ offset = pos & (blocksize - 1);
+ num_blocks = ((offset + count - 1) >> blocksize_bits) + 1;
+ start_blk = pos >> blocksize_bits;
+ end_blk = start_blk + num_blocks - 1;
+
+ NOVA_START_TIMING(protect_memcpy_t, memcpy_time);
+ blockbuf = kmalloc(blocksize, GFP_KERNEL);
+ if (blockbuf == NULL) {
+ nova_err(sb, "%s: block buffer allocation error\n", __func__);
+ return -ENOMEM;
+ }
+
+ bytes = blocksize - offset;
+ if (bytes > count)
+ bytes = count;
+
+ left = copy_from_user(blockbuf + offset, buf, bytes);
+ NOVA_END_TIMING(protect_memcpy_t, memcpy_time);
+ if (unlikely(left != 0)) {
+ nova_err(sb, "%s: not all data is copied from user! expect to
copy %zu bytes, actually copied %zu bytes\n",
+ __func__, bytes, bytes - left);
+ ret = -EFAULT;
+ goto out;
+ }
+
+ entryc = (metadata_csum == 0) ? entry : &entry_copy;
+
+ if (offset != 0) {
+ NOVA_STATS_ADD(protect_head, 1);
+ entry = nova_get_write_entry(sb, sih, start_blk);
+ if (entry != NULL) {
+ if (metadata_csum == 0)
+ entryc = entry;
+ else if (!nova_verify_entry_csum(sb, entry, entryc))
+ return -EIO;
+
+ /* make sure data in the partial block head is good */
+ nvmm = get_nvmm(sb, sih, entryc, start_blk);
+ nvmmoff = nova_get_block_off(sb, nvmm, sih->i_blk_type);
+ blockptr = (u8 *) nova_get_block(sb, nvmmoff);
+
+ mapped = nova_find_pgoff_in_vma(inode, start_blk);
+ if (data_csum > 0 && !mapped && !inplace) {
+ nvmm_ok = nova_verify_data_csum(sb, sih, nvmm,
+ 0, offset);
+ if (!nvmm_ok) {
+ ret = -EIO;
+ goto out;
+ }
+ }
+
+ ret = memcpy_mcsafe(blockbuf, blockptr, offset);
+ if (ret < 0)
+ goto out;
+ } else {
+ memset(blockbuf, 0, offset);
+ }
+
+ /* copying existing checksums from nvmm can be even slower than
+ * re-computing checksums of a whole block.
+ if (data_csum > 0)
+ nova_copy_partial_block_csum(sb, sih, entry, start_blk,
+ offset, blocknr, false);
+ */
+ }
+
+ if (num_blocks == 1)
+ goto eblk;
+
+ do {
+ if (inplace)
+ nova_update_block_csum_parity(sb, sih, blockbuf,
+ blocknr, offset, bytes);
+ else
+ nova_update_block_csum_parity(sb, sih, blockbuf,
+ blocknr, 0, blocksize);
+
+ blocknr++;
+ pos += bytes;
+ buf += bytes;
+ count -= bytes;
+ offset = pos & (blocksize - 1);
+
+ bytes = count < blocksize ? count : blocksize;
+ left = copy_from_user(blockbuf, buf, bytes);
+ if (unlikely(left != 0)) {
+ nova_err(sb, "%s: not all data is copied from user!
expect to copy %zu bytes, actually copied %zu bytes\n",
+ __func__, bytes, bytes - left);
+ ret = -EFAULT;
+ goto out;
+ }
+ } while (count > blocksize);
+
+eblk:
+ eblk_offset = (pos + count) & (blocksize - 1);
+
+ if (eblk_offset != 0) {
+ NOVA_STATS_ADD(protect_tail, 1);
+ entry = nova_get_write_entry(sb, sih, end_blk);
+ if (entry != NULL) {
+ if (metadata_csum == 0)
+ entryc = entry;
+ else if (!nova_verify_entry_csum(sb, entry, entryc))
+ return -EIO;
+
+ /* make sure data in the partial block tail is good */
+ nvmm = get_nvmm(sb, sih, entryc, end_blk);
+ nvmmoff = nova_get_block_off(sb, nvmm, sih->i_blk_type);
+ blockptr = (u8 *) nova_get_block(sb, nvmmoff);
+
+ mapped = nova_find_pgoff_in_vma(inode, end_blk);
+ if (data_csum > 0 && !mapped && !inplace) {
+ nvmm_ok = nova_verify_data_csum(sb, sih, nvmm,
+ eblk_offset, blocksize - eblk_offset);
+ if (!nvmm_ok) {
+ ret = -EIO;
+ goto out;
+ }
+ }
+
+ ret = memcpy_mcsafe(blockbuf + eblk_offset,
+ blockptr + eblk_offset,
+ blocksize - eblk_offset);
+ if (ret < 0)
+ goto out;
+ } else {
+ memset(blockbuf + eblk_offset, 0,
+ blocksize - eblk_offset);
+ }
+
+ /* copying existing checksums from nvmm can be even slower than
+ * re-computing checksums of a whole block.
+ if (data_csum > 0)
+ nova_copy_partial_block_csum(sb, sih, entry, end_blk,
+ eblk_offset, blocknr, true);
+ */
+ }
+
+ if (inplace)
+ nova_update_block_csum_parity(sb, sih, blockbuf, blocknr,
+ offset, bytes);
+ else
+ nova_update_block_csum_parity(sb, sih, blockbuf, blocknr,
+ 0, blocksize);
+
+out:
+ if (blockbuf != NULL)
+ kfree(blockbuf);
+
+ NOVA_END_TIMING(protect_file_data_t, protect_file_data_time);
+
+ return ret;
+}
+
+static bool nova_get_verify_entry(struct super_block *sb,
+ struct nova_file_write_entry *entry,
+ struct nova_file_write_entry *entryc,
+ int locked)
+{
+ int ret = 0;
+
+ if (metadata_csum == 0)
+ return true;
+
+ if (locked == 0) {
+ /* Someone else may be updating the entry. Skip check */
+ ret = memcpy_mcsafe(entryc, entry,
+ sizeof(struct nova_file_write_entry));
+ if (ret < 0)
+ return false;
+
+ return true;
+ }
+
+ return nova_verify_entry_csum(sb, entry, entryc);
+}
+
+/*
+ * Check if there is an existing entry for target page offset.
+ * Used for inplace write, direct IO, DAX-mmap and fallocate.
+ */
+unsigned long nova_check_existing_entry(struct super_block *sb,
+ struct inode *inode, unsigned long num_blocks, unsigned long start_blk,
+ struct nova_file_write_entry **ret_entry,
+ struct nova_file_write_entry *ret_entryc, int check_next, u64 epoch_id,
+ int *inplace, int locked)
+{
+ struct nova_inode_info *si = NOVA_I(inode);
+ struct nova_inode_info_header *sih = &si->header;
+ struct nova_file_write_entry *entry;
+ struct nova_file_write_entry *entryc;
+ unsigned long next_pgoff;
+ unsigned long ent_blks = 0;
+ timing_t check_time;
+
+ NOVA_START_TIMING(check_entry_t, check_time);
+
+ *ret_entry = NULL;
+ *inplace = 0;
+ entry = nova_get_write_entry(sb, sih, start_blk);
+
+ entryc = (metadata_csum == 0) ? entry : ret_entryc;
+
+ if (entry) {
+ if (metadata_csum == 0)
+ entryc = entry;
+ else if (!nova_get_verify_entry(sb, entry, entryc, locked))
+ goto out;
+
+ *ret_entry = entry;
+
+ /* We can do inplace write. Find contiguous blocks */
+ if (entryc->reassigned == 0)
+ ent_blks = entryc->num_pages -
+ (start_blk - entryc->pgoff);
+ else
+ ent_blks = 1;
+
+ if (ent_blks > num_blocks)
+ ent_blks = num_blocks;
+
+ if (entryc->epoch_id == epoch_id)
+ *inplace = 1;
+
+ } else if (check_next) {
+ /* Possible Hole */
+ entry = nova_find_next_entry(sb, sih, start_blk);
+ if (entry) {
+ if (metadata_csum == 0)
+ entryc = entry;
+ else if (!nova_get_verify_entry(sb, entry, entryc,
+ locked))
+ goto out;
+
+ next_pgoff = entryc->pgoff;
+ if (next_pgoff <= start_blk) {
+ nova_err(sb, "iblock %lu, entry pgoff %lu, num
pages %lu\n",
+ start_blk, next_pgoff, entry->num_pages);
+ nova_print_inode_log(sb, inode);
+ BUG();
+ ent_blks = num_blocks;
+ goto out;
+ }
+ ent_blks = next_pgoff - start_blk;
+ if (ent_blks > num_blocks)
+ ent_blks = num_blocks;
+ } else {
+ /* File grow */
+ ent_blks = num_blocks;
+ }
+ }
+
+ if (entry && ent_blks == 0) {
+ nova_dbg("%s: %d\n", __func__, check_next);
+ dump_stack();
+ }
+
+out:
+ NOVA_END_TIMING(check_entry_t, check_time);
+ return ent_blks;
+}
+
+ssize_t nova_inplace_file_write(struct file *filp,
+ const char __user *buf, size_t len, loff_t *ppos)
+{
+ struct address_space *mapping = filp->f_mapping;
+ struct inode *inode = mapping->host;
+ struct nova_inode_info *si = NOVA_I(inode);
+ struct nova_inode_info_header *sih = &si->header;
+ struct super_block *sb = inode->i_sb;
+ struct nova_inode *pi, inode_copy;
+ struct nova_file_write_entry *entry;
+ struct nova_file_write_entry *entryc, entry_copy;
+ struct nova_file_write_entry entry_data;
+ struct nova_inode_update update;
+ ssize_t written = 0;
+ loff_t pos;
+ size_t count, offset, copied;
+ unsigned long start_blk, num_blocks, ent_blks = 0;
+ unsigned long total_blocks;
+ unsigned long blocknr = 0;
+ unsigned int data_bits;
+ int allocated = 0;
+ int inplace = 0;
+ bool hole_fill = false;
+ bool update_log = false;
+ void *kmem;
+ u64 blk_off;
+ size_t bytes;
+ long status = 0;
+ timing_t inplace_write_time, memcpy_time;
+ unsigned long step = 0;
+ u64 begin_tail = 0;
+ u64 epoch_id;
+ u64 file_size;
+ u32 time;
+ ssize_t ret;
+
+
+ if (len == 0)
+ return 0;
+
+
+ NOVA_START_TIMING(inplace_write_t, inplace_write_time);
+
+ sb_start_write(inode->i_sb);
+ inode_lock(inode);
+
+ if (!access_ok(VERIFY_READ, buf, len)) {
+ ret = -EFAULT;
+ goto out;
+ }
+ pos = *ppos;
+
+ if (filp->f_flags & O_APPEND)
+ pos = i_size_read(inode);
+
+ count = len;
+
+ pi = nova_get_block(sb, sih->pi_addr);
+
+ /* nova_inode tail pointer will be updated and we make sure all other
+ * inode fields are good before checksumming the whole structure
+ */
+ if (nova_check_inode_integrity(sb, sih->ino, sih->pi_addr,
+ sih->alter_pi_addr, &inode_copy, 0) < 0) {
+ ret = -EIO;
+ goto out;
+ }
+
+ offset = pos & (sb->s_blocksize - 1);
+ num_blocks = ((count + offset - 1) >> sb->s_blocksize_bits) + 1;
+ total_blocks = num_blocks;
+
+ /* offset in the actual block size block */
+
+ ret = file_remove_privs(filp);
+ if (ret)
+ goto out;
+
+ inode->i_ctime = inode->i_mtime = current_time(inode);
+ time = current_time(inode).tv_sec;
+
+ epoch_id = nova_get_epoch_id(sb);
+
+ nova_dbgv("%s: epoch_id %llu, inode %lu, offset %lld, count %lu\n",
+ __func__, epoch_id, inode->i_ino, pos, count);
+ update.tail = sih->log_tail;
+ update.alter_tail = sih->alter_log_tail;
+ while (num_blocks > 0) {
+ hole_fill = false;
+ offset = pos & (nova_inode_blk_size(sih) - 1);
+ start_blk = pos >> sb->s_blocksize_bits;
+
+ ent_blks = nova_check_existing_entry(sb, inode, num_blocks,
+ start_blk, &entry, &entry_copy,
+ 1, epoch_id, &inplace, 1);
+
+ entryc = (metadata_csum == 0) ? entry : &entry_copy;
+
+ if (entry && inplace) {
+ /* We can do inplace write. Find contiguous blocks */
+ blocknr = get_nvmm(sb, sih, entryc, start_blk);
+ blk_off = blocknr << PAGE_SHIFT;
+ allocated = ent_blks;
+ if (data_csum || data_parity)
+ nova_set_write_entry_updating(sb, entry, 1);
+ } else {
+ /* Allocate blocks to fill hole */
+ allocated = nova_new_data_blocks(sb, sih, &blocknr,
+ start_blk, ent_blks, ALLOC_NO_INIT,
+ ANY_CPU, ALLOC_FROM_HEAD);
+
+ nova_dbg_verbose("%s: alloc %d blocks @ %lu\n",
+ __func__, allocated, blocknr);
+
+ if (allocated <= 0) {
+ nova_dbg("%s alloc blocks failed!, %d\n",
+ __func__, allocated);
+ ret = allocated;
+ goto out;
+ }
+
+ hole_fill = true;
+ blk_off = nova_get_block_off(sb, blocknr,
+ sih->i_blk_type);
+ }
+
+ step++;
+ bytes = sb->s_blocksize * allocated - offset;
+ if (bytes > count)
+ bytes = count;
+
+ kmem = nova_get_block(inode->i_sb, blk_off);
+
+ if (hole_fill &&
+ (offset || ((offset + bytes) & (PAGE_SIZE - 1)) != 0)) {
+ ret = nova_handle_head_tail_blocks(sb, inode,
+ pos, bytes, kmem);
+ if (ret)
+ goto out;
+
+ }
+
+ /* Now copy from user buf */
+// nova_dbg("Write: %p\n", kmem);
+ NOVA_START_TIMING(memcpy_w_nvmm_t, memcpy_time);
+ nova_memunlock_range(sb, kmem + offset, bytes);
+ copied = bytes - memcpy_to_pmem_nocache(kmem + offset,
+ buf, bytes);
+ nova_memlock_range(sb, kmem + offset, bytes);
+ NOVA_END_TIMING(memcpy_w_nvmm_t, memcpy_time);
+
+ if (data_csum > 0 || data_parity > 0) {
+ ret = nova_protect_file_data(sb, inode, pos, bytes,
+ buf, blocknr, !hole_fill);
+ if (ret)
+ goto out;
+ }
+
+ if (pos + copied > inode->i_size)
+ file_size = cpu_to_le64(pos + copied);
+ else
+ file_size = cpu_to_le64(inode->i_size);
+
+ /* Handle hole fill write */
+ if (hole_fill) {
+ nova_init_file_write_entry(sb, sih, &entry_data,
+ epoch_id, start_blk, allocated,
+ blocknr, time, file_size);
+
+ ret = nova_append_file_write_entry(sb, pi, inode,
+ &entry_data, &update);
+ if (ret) {
+ nova_dbg("%s: append inode entry failed\n",
+ __func__);
+ ret = -ENOSPC;
+ goto out;
+ }
+ } else {
+ /* Update existing entry */
+ struct nova_log_entry_info entry_info;
+
+ entry_info.type = FILE_WRITE;
+ entry_info.epoch_id = epoch_id;
+ entry_info.trans_id = sih->trans_id;
+ entry_info.time = time;
+ entry_info.file_size = file_size;
+ entry_info.inplace = 1;
+
+ nova_inplace_update_write_entry(sb, inode, entry,
+ &entry_info);
+ }
+
+ nova_dbgv("Write: %p, %lu\n", kmem, copied);
+ if (copied > 0) {
+ status = copied;
+ written += copied;
+ pos += copied;
+ buf += copied;
+ count -= copied;
+ num_blocks -= allocated;
+ }
+ if (unlikely(copied != bytes)) {
+ nova_dbg("%s ERROR!: %p, bytes %lu, copied %lu\n",
+ __func__, kmem, bytes, copied);
+ if (status >= 0)
+ status = -EFAULT;
+ }
+ if (status < 0)
+ break;
+
+ if (hole_fill) {
+ update_log = true;
+ if (begin_tail == 0)
+ begin_tail = update.curr_entry;
+ }
+ }
+
+ data_bits = blk_type_to_shift[sih->i_blk_type];
+ sih->i_blocks += (total_blocks << (data_bits - sb->s_blocksize_bits));
+
+ inode->i_blocks = sih->i_blocks;
+
+ if (update_log) {
+ nova_memunlock_inode(sb, pi);
+ nova_update_inode(sb, inode, pi, &update, 1);
+ nova_memlock_inode(sb, pi);
+ NOVA_STATS_ADD(inplace_new_blocks, 1);
+
+ /* Update file tree */
+ ret = nova_reassign_file_tree(sb, sih, begin_tail);
+ if (ret)
+ goto out;
+ }
+
+ ret = written;
+ NOVA_STATS_ADD(inplace_write_breaks, step);
+ nova_dbgv("blocks: %lu, %lu\n", inode->i_blocks, sih->i_blocks);
+
+ *ppos = pos;
+ if (pos > inode->i_size) {
+ i_size_write(inode, pos);
+ sih->i_size = pos;
+ }
+
+ sih->trans_id++;
+out:
+ if (ret < 0)
+ nova_cleanup_incomplete_write(sb, sih, blocknr, allocated,
+ begin_tail, update.tail);
+
+ inode_unlock(inode);
+ sb_end_write(inode->i_sb);
+ NOVA_END_TIMING(inplace_write_t, inplace_write_time);
+ NOVA_STATS_ADD(inplace_write_bytes, written);
+ return ret;
+}
+
+/* Check if existing entry overlap with vma regions */
+int nova_check_overlap_vmas(struct super_block *sb,
+ struct nova_inode_info_header *sih,
+ unsigned long pgoff, unsigned long num_pages)
+{
+ unsigned long start_pgoff = 0;
+ unsigned long num = 0;
+ unsigned long i;
+ struct vma_item *item;
+ struct rb_node *temp;
+ int ret = 0;
+
+ if (sih->num_vmas == 0)
+ return 0;
+
+ temp = rb_first(&sih->vma_tree);
+ while (temp) {
+ item = container_of(temp, struct vma_item, node);
+ temp = rb_next(temp);
+ ret = nova_get_vma_overlap_range(sb, sih, item->vma, pgoff,
+ num_pages, &start_pgoff, &num);
+ if (ret) {
+ for (i = 0; i < num; i++) {
+ if (nova_get_write_entry(sb, sih,
+ start_pgoff + i))
+ return 1;
+ }
+ }
+ }
+
+ return 0;
+}
+
+
+/*
+ * return > 0, # of blocks mapped or allocated.
+ * return = 0, if plain lookup failed.
+ * return < 0, error case.
+ */
+int nova_dax_get_blocks(struct inode *inode, sector_t iblock,
+ unsigned long max_blocks, u32 *bno, bool *new, bool *boundary,
+ int create, bool taking_lock)
+{
+ struct super_block *sb = inode->i_sb;
+ struct nova_inode *pi;
+ struct nova_inode_info *si = NOVA_I(inode);
+ struct nova_inode_info_header *sih = &si->header;
+ struct nova_file_write_entry *entry = NULL;
+ struct nova_file_write_entry *entryc, entry_copy;
+ struct nova_file_write_entry entry_data;
+ struct nova_inode_update update;
+ u32 time;
+ unsigned int data_bits;
+ unsigned long nvmm = 0;
+ unsigned long blocknr = 0;
+ u64 epoch_id;
+ int num_blocks = 0;
+ int inplace = 0;
+ int allocated = 0;
+ int locked = 0;
+ int check_next = 1;
+ int ret = 0;
+ timing_t get_block_time;
+
+
+ if (max_blocks == 0)
+ return 0;
+
+ NOVA_START_TIMING(dax_get_block_t, get_block_time);
+
+ nova_dbgv("%s: pgoff %lu, num %lu, create %d\n",
+ __func__, iblock, max_blocks, create);
+
+ epoch_id = nova_get_epoch_id(sb);
+
+ if (taking_lock)
+ check_next = 0;
+
+again:
+ num_blocks = nova_check_existing_entry(sb, inode, max_blocks,
+ iblock, &entry, &entry_copy, check_next,
+ epoch_id, &inplace, locked);
+
+ entryc = (metadata_csum == 0) ? entry : &entry_copy;
+
+ if (entry) {
+ if (create == 0 || inplace) {
+ nvmm = get_nvmm(sb, sih, entryc, iblock);
+ nova_dbgv("%s: found pgoff %lu, block %lu\n",
+ __func__, iblock, nvmm);
+ goto out;
+ }
+ }
+
+ if (create == 0) {
+ num_blocks = 0;
+ goto out1;
+ }
+
+ if (taking_lock && locked == 0) {
+ inode_lock(inode);
+ locked = 1;
+ /* Check again incase someone has done it for us */
+ check_next = 1;
+ goto again;
+ }
+
+ pi = nova_get_inode(sb, inode);
+ inode->i_ctime = inode->i_mtime = current_time(inode);
+ time = current_time(inode).tv_sec;
+ update.tail = sih->log_tail;
+ update.alter_tail = sih->alter_log_tail;
+
+ /* Return initialized blocks to the user */
+ allocated = nova_new_data_blocks(sb, sih, &blocknr, iblock,
+ num_blocks, ALLOC_INIT_ZERO, ANY_CPU,
+ ALLOC_FROM_HEAD);
+ if (allocated <= 0) {
+ nova_dbgv("%s alloc blocks failed %d\n", __func__,
+ allocated);
+ ret = allocated;
+ goto out;
+ }
+
+ num_blocks = allocated;
+ /* Do not extend file size */
+ nova_init_file_write_entry(sb, sih, &entry_data,
+ epoch_id, iblock, num_blocks,
+ blocknr, time, inode->i_size);
+
+ ret = nova_append_file_write_entry(sb, pi, inode,
+ &entry_data, &update);
+ if (ret) {
+ nova_dbgv("%s: append inode entry failed\n", __func__);
+ ret = -ENOSPC;
+ goto out;
+ }
+
+ nvmm = blocknr;
+ data_bits = blk_type_to_shift[sih->i_blk_type];
+ sih->i_blocks += (num_blocks << (data_bits - sb->s_blocksize_bits));
+
+ nova_memunlock_inode(sb, pi);
+ nova_update_inode(sb, inode, pi, &update, 1);
+ nova_memlock_inode(sb, pi);
+
+ ret = nova_reassign_file_tree(sb, sih, update.curr_entry);
+ if (ret) {
+ nova_dbgv("%s: nova_reassign_file_tree failed: %d\n",
+ __func__, ret);
+ goto out;
+ }
+ inode->i_blocks = sih->i_blocks;
+ sih->trans_id++;
+ NOVA_STATS_ADD(dax_new_blocks, 1);
+
+// set_buffer_new(bh);
+out:
+ if (ret < 0) {
+ nova_cleanup_incomplete_write(sb, sih, blocknr, allocated,
+ 0, update.tail);
+ num_blocks = ret;
+ goto out1;
+ }
+
+ *bno = nvmm;
+// if (num_blocks > 1)
+// bh->b_size = sb->s_blocksize * num_blocks;
+
+out1:
+ if (taking_lock && locked)
+ inode_unlock(inode);
+
+ NOVA_END_TIMING(dax_get_block_t, get_block_time);
+ return num_blocks;
+}
+
+int nova_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
+ unsigned int flags, struct iomap *iomap, bool taking_lock)
+{
+ struct nova_sb_info *sbi = NOVA_SB(inode->i_sb);
+ unsigned int blkbits = inode->i_blkbits;
+ unsigned long first_block = offset >> blkbits;
+ unsigned long max_blocks = (length + (1 << blkbits) - 1) >> blkbits;
+ bool new = false, boundary = false;
+ u32 bno;
+ int ret;
+
+ ret = nova_dax_get_blocks(inode, first_block, max_blocks, &bno, &new,
+ &boundary, flags & IOMAP_WRITE, taking_lock);
+ if (ret < 0) {
+ nova_dbgv("%s: nova_dax_get_blocks failed %d", __func__, ret);
+ return ret;
+ }
+
+ iomap->flags = 0;
+ iomap->bdev = inode->i_sb->s_bdev;
+ iomap->dax_dev = sbi->s_dax_dev;
+ iomap->offset = (u64)first_block << blkbits;
+
+ if (ret == 0) {
+ iomap->type = IOMAP_HOLE;
+ iomap->blkno = IOMAP_NULL_BLOCK;
+ iomap->length = 1 << blkbits;
+ } else {
+ iomap->type = IOMAP_MAPPED;
+ iomap->blkno = (sector_t)bno << (blkbits - 9);
+ iomap->length = (u64)ret << blkbits;
+ iomap->flags |= IOMAP_F_MERGED;
+ }
+
+ if (new)
+ iomap->flags |= IOMAP_F_NEW;
+ return 0;
+}
+
+int nova_iomap_end(struct inode *inode, loff_t offset, loff_t length,
+ ssize_t written, unsigned int flags, struct iomap *iomap)
+{
+ if (iomap->type == IOMAP_MAPPED &&
+ written < length &&
+ (flags & IOMAP_WRITE))
+ truncate_pagecache(inode, inode->i_size);
+ return 0;
+}
+
+
+static int nova_iomap_begin_lock(struct inode *inode, loff_t offset,
+ loff_t length, unsigned int flags, struct iomap *iomap)
+{
+ return nova_iomap_begin(inode, offset, length, flags, iomap, true);
+}
+
+static struct iomap_ops nova_iomap_ops_lock = {
+ .iomap_begin = nova_iomap_begin_lock,
+ .iomap_end = nova_iomap_end,
+};
+
+
+static int nova_dax_huge_fault(struct vm_fault *vmf,
+ enum page_entry_size pe_size)
+{
+ int ret = 0;
+ timing_t fault_time;
+ struct address_space *mapping = vmf->vma->vm_file->f_mapping;
+ struct inode *inode = mapping->host;
+
+ NOVA_START_TIMING(pmd_fault_t, fault_time);
+
+ nova_dbgv("%s: inode %lu, pgoff %lu\n",
+ __func__, inode->i_ino, vmf->pgoff);
+
+ ret = dax_iomap_fault(vmf, pe_size, &nova_iomap_ops_lock);
+
+ NOVA_END_TIMING(pmd_fault_t, fault_time);
+ return ret;
+}
+
+static int nova_dax_fault(struct vm_fault *vmf)
+{
+ struct address_space *mapping = vmf->vma->vm_file->f_mapping;
+ struct inode *inode = mapping->host;
+
+ nova_dbgv("%s: inode %lu, pgoff %lu\n",
+ __func__, inode->i_ino, vmf->pgoff);
+
+ return nova_dax_huge_fault(vmf, PE_SIZE_PTE);
+}
+
+static int nova_dax_pfn_mkwrite(struct vm_fault *vmf)
+{
+ struct inode *inode = file_inode(vmf->vma->vm_file);
+ loff_t size;
+ int ret = 0;
+ timing_t fault_time;
+
+ NOVA_START_TIMING(pfn_mkwrite_t, fault_time);
+
+ inode_lock(inode);
+ size = (i_size_read(inode) + PAGE_SIZE - 1) >> PAGE_SHIFT;
+ if (vmf->pgoff >= size)
+ ret = VM_FAULT_SIGBUS;
+ else
+ ret = dax_pfn_mkwrite(vmf);
+ inode_unlock(inode);
+
+ NOVA_END_TIMING(pfn_mkwrite_t, fault_time);
+ return ret;
+}
+
+static inline int nova_rbtree_compare_vma(struct vma_item *curr,
+ struct vm_area_struct *vma)
+{
+ if (vma < curr->vma)
+ return -1;
+ if (vma > curr->vma)
+ return 1;
+
+ return 0;
+}
+
+static int nova_append_write_mmap_to_log(struct super_block *sb,
+ struct inode *inode, struct vma_item *item)
+{
+ struct vm_area_struct *vma = item->vma;
+ struct nova_inode *pi;
+ struct nova_mmap_entry data;
+ struct nova_inode_update update;
+ unsigned long num_pages;
+ u64 epoch_id;
+ int ret;
+
+ /* Only for csum and parity update */
+ if (data_csum == 0 && data_parity == 0)
+ return 0;
+
+ pi = nova_get_inode(sb, inode);
+ epoch_id = nova_get_epoch_id(sb);
+ update.tail = update.alter_tail = 0;
+
+ memset(&data, 0, sizeof(struct nova_mmap_entry));
+ data.entry_type = MMAP_WRITE;
+ data.epoch_id = epoch_id;
+ data.pgoff = cpu_to_le64(vma->vm_pgoff);
+ num_pages = (vma->vm_end - vma->vm_start) >> PAGE_SHIFT;
+ data.num_pages = cpu_to_le64(num_pages);
+ data.invalid = 0;
+
+ nova_dbgv("%s : Appending mmap log entry for inode %lu, pgoff %llu,
%llu pages\n",
+ __func__, inode->i_ino,
+ data.pgoff, data.num_pages);
+
+ ret = nova_append_mmap_entry(sb, pi, inode, &data, &update, item);
+ if (ret) {
+ nova_dbg("%s: append write mmap entry failure\n", __func__);
+ goto out;
+ }
+
+ nova_memunlock_inode(sb, pi);
+ nova_update_inode(sb, inode, pi, &update, 1);
+ nova_memlock_inode(sb, pi);
+out:
+ return ret;
+}
+
+int nova_insert_write_vma(struct vm_area_struct *vma)
+{
+ struct address_space *mapping = vma->vm_file->f_mapping;
+ struct inode *inode = mapping->host;
+ struct nova_inode_info *si = NOVA_I(inode);
+ struct nova_inode_info_header *sih = &si->header;
+ struct super_block *sb = inode->i_sb;
+ struct nova_sb_info *sbi = NOVA_SB(sb);
+ unsigned long flags = VM_SHARED | VM_WRITE;
+ struct vma_item *item, *curr;
+ struct rb_node **temp, *parent;
+ int compVal;
+ int insert = 0;
+ int ret;
+ timing_t insert_vma_time;
+
+
+ if ((vma->vm_flags & flags) != flags)
+ return 0;
+
+ NOVA_START_TIMING(insert_vma_t, insert_vma_time);
+
+ item = nova_alloc_vma_item(sb);
+ if (!item) {
+ NOVA_END_TIMING(insert_vma_t, insert_vma_time);
+ return -ENOMEM;
+ }
+
+ item->vma = vma;
+
+ nova_dbgv("Inode %lu insert vma %p, start 0x%lx, end 0x%lx, pgoff
%lu\n",
+ inode->i_ino, vma, vma->vm_start, vma->vm_end,
+ vma->vm_pgoff);
+
+ inode_lock(inode);
+
+ /* Append to log */
+ ret = nova_append_write_mmap_to_log(sb, inode, item);
+ if (ret)
+ goto out;
+
+ temp = &(sih->vma_tree.rb_node);
+ parent = NULL;
+
+ while (*temp) {
+ curr = container_of(*temp, struct vma_item, node);
+ compVal = nova_rbtree_compare_vma(curr, vma);
+ parent = *temp;
+
+ if (compVal == -1) {
+ temp = &((*temp)->rb_left);
+ } else if (compVal == 1) {
+ temp = &((*temp)->rb_right);
+ } else {
+ nova_dbg("%s: vma %p already exists\n",
+ __func__, vma);
+ kfree(item);
+ goto out;
+ }
+ }
+
+ rb_link_node(&item->node, parent, temp);
+ rb_insert_color(&item->node, &sih->vma_tree);
+
+ sih->num_vmas++;
+ if (sih->num_vmas == 1)
+ insert = 1;
+
+ sih->trans_id++;
+out:
+ inode_unlock(inode);
+
+ if (insert) {
+ mutex_lock(&sbi->vma_mutex);
+ list_add_tail(&sih->list, &sbi->mmap_sih_list);
+ mutex_unlock(&sbi->vma_mutex);
+ }
+
+ NOVA_END_TIMING(insert_vma_t, insert_vma_time);
+ return ret;
+}
+
+static int nova_remove_write_vma(struct vm_area_struct *vma)
+{
+ struct address_space *mapping = vma->vm_file->f_mapping;
+ struct inode *inode = mapping->host;
+ struct nova_inode_info *si = NOVA_I(inode);
+ struct nova_inode_info_header *sih = &si->header;
+ struct super_block *sb = inode->i_sb;
+ struct nova_sb_info *sbi = NOVA_SB(sb);
+ struct vma_item *curr = NULL;
+ struct rb_node *temp;
+ int compVal;
+ int found = 0;
+ int remove = 0;
+ timing_t remove_vma_time;
+
+
+ NOVA_START_TIMING(remove_vma_t, remove_vma_time);
+ inode_lock(inode);
+
+ temp = sih->vma_tree.rb_node;
+ while (temp) {
+ curr = container_of(temp, struct vma_item, node);
+ compVal = nova_rbtree_compare_vma(curr, vma);
+
+ if (compVal == -1) {
+ temp = temp->rb_left;
+ } else if (compVal == 1) {
+ temp = temp->rb_right;
+ } else {
+ nova_reset_vma_csum_parity(sb, curr);
+ rb_erase(&curr->node, &sih->vma_tree);
+ found = 1;
+ break;
+ }
+ }
+
+ if (found) {
+ sih->num_vmas--;
+ if (sih->num_vmas == 0)
+ remove = 1;
+ }
+
+ inode_unlock(inode);
+
+ if (found) {
+ nova_dbgv("Inode %lu remove vma %p, start 0x%lx, end 0x%lx,
pgoff %lu\n",
+ inode->i_ino, curr->vma, curr->vma->vm_start,
+ curr->vma->vm_end, curr->vma->vm_pgoff);
+ nova_free_vma_item(sb, curr);
+ }
+
+ if (remove) {
+ mutex_lock(&sbi->vma_mutex);
+ list_del(&sih->list);
+ mutex_unlock(&sbi->vma_mutex);
+ }
+
+ NOVA_END_TIMING(remove_vma_t, remove_vma_time);
+ return 0;
+}
+
+static int nova_restore_page_write(struct vm_area_struct *vma,
+ unsigned long address)
+{
+ struct mm_struct *mm = vma->vm_mm;
+
+
+ down_write(&mm->mmap_sem);
+
+ nova_dbgv("Restore vma %p write, start 0x%lx, end 0x%lx, address
0x%lx\n",
+ vma, vma->vm_start, vma->vm_end, address);
+
+ /* Restore single page write */
+ nova_mmap_to_new_blocks(vma, address);
+
+ up_write(&mm->mmap_sem);
+
+ return 0;
+}
+
+static void nova_vma_open(struct vm_area_struct *vma)
+{
+ struct address_space *mapping = vma->vm_file->f_mapping;
+ struct inode *inode = mapping->host;
+
+ nova_dbg_mmap4k("[%s:%d] inode %lu, MMAP 4KPAGE vm_start(0x%lx),
vm_end(0x%lx), vm pgoff %lu, %lu blocks, vm_flags(0x%lx),
vm_page_prot(0x%lx)\n",
+ __func__, __LINE__,
+ inode->i_ino, vma->vm_start, vma->vm_end,
+ vma->vm_pgoff,
+ (vma->vm_end - vma->vm_start) >> PAGE_SHIFT,
+ vma->vm_flags,
+ pgprot_val(vma->vm_page_prot));
+
+ nova_insert_write_vma(vma);
+}
+
+static void nova_vma_close(struct vm_area_struct *vma)
+{
+ nova_dbgv("[%s:%d] MMAP 4KPAGE vm_start(0x%lx), vm_end(0x%lx),
vm_flags(0x%lx), vm_page_prot(0x%lx)\n",
+ __func__, __LINE__, vma->vm_start, vma->vm_end,
+ vma->vm_flags, pgprot_val(vma->vm_page_prot));
+
+ vma->original_write = 0;
+ nova_remove_write_vma(vma);
+}
+
+const struct vm_operations_struct nova_dax_vm_ops = {
+ .fault = nova_dax_fault,
+ .huge_fault = nova_dax_huge_fault,
+ .page_mkwrite = nova_dax_fault,
+ .pfn_mkwrite = nova_dax_pfn_mkwrite,
+ .open = nova_vma_open,
+ .close = nova_vma_close,
+ .dax_cow = nova_restore_page_write,
+};
+
