[RFC PATCH 3/3] ocfs2: switch dio write path from buffer_head to iomap
Heming Zhao <[email protected]> Fri, 24 Jul 2026 13:25:57 +0800
| Newsgroups | dev.linux.lists.ocfs2-devel,org.kernel.vger.linux-kernel |
|---|---|
| Message-ID | <[email protected]> |
This patch converts OCFS2's DIO write path from the legacy
buffer_head infrastructure to the modern iomap framework.
Key modifications and designs are as follows:
1. Dynamic Context Allocation:
Refactor 'struct ocfs2_write_ctxt' to use a flexible array 'w_desc[]'
instead of a fixed-size array. Dynamically allocate the context based on
the write length ('w_clen') in 'ocfs2_alloc_write_ctxt()'. This prevents
static limits overflow and optimizes kernel heap memory utilization.
2. Robust Mapping and Limits:
Introduce 'ocfs2_dio_wr_map_blocks()' to allocate and map direct write
blocks. Implement a 1 MiB cap ('OCFS2_DIO_WR_MAX_MAX_BYTES') per mapping
call to restrict allocation granularity, preventing JBD2 transaction
credit exhaustion during huge asynchronous sequential writes.
3. Reliable Completion Work and Fallback:
- Implement 'ocfs2_iomap_dio_end_io_write()' to handle metadata completion.
It converts UNWRITTEN extents, updates inode size (EOF), and deletes the
inode from the orphan directory if it was appended.
- Implement 'ocfs2_dio_write_end_io()' to finalize the dio lifecycle and
release cluster locks safely.
- Intercept '-ENOTBLK' errors from 'iomap_dio_rw()' caused by page cache
invalidation failures (due to mmap/buffered collisions). Gracefully clear
the error, strip the IOCB_DIRECT flag, and fall back to buffered write
4. Moved ocfs2_add_inode_to_orphan():
- moved ocfs2_add_inode_to_orphan() from ocfs2_dio_wr_map_blocks() to
ocfs2_file_write_iter().
5. Uncertain logic in code
For the following code block in ocfs2_dio_wr_map_blocks():
```
if (extend) {
if (ocfs2_sparse_alloc(osb))
ret = ocfs2_zero_tail(inode, di_bh, pos);
else
ret = ocfs2_expand_nonsparse_inode(inode, di_bh, pos,
map_len, NULL);
if (ret < 0) {
mlog_errno(ret);
goto unlock;
}
}
```
I am not completely certain whether it is called only once per
ocfs2_file_write_iter(), but I believe calling it multiple times will
not introduce any side effects. Furthermore, testing across various
scenarios showed no instances of multiple calls.
Assisted-by: Gemini:gemini-3.5-flash
Assisted-by: Claude:claude-sonnet-4-5
Signed-off-by: Heming Zhao <[email protected]>
---
fs/ocfs2/aops.c | 387 +++++++++++++++++++++++++++++++++++++-
fs/ocfs2/buffer_head_io.c | 7 +-
fs/ocfs2/file.c | 55 +++++-
fs/ocfs2/ocfs2.h | 1 +
4 files changed, 435 insertions(+), 15 deletions(-)
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c
index 59d445dd61f6..60bf0973f38d 100644
--- a/fs/ocfs2/aops.c
+++ b/fs/ocfs2/aops.c
@@ -764,6 +764,8 @@ int ocfs2_map_folio_blocks(struct folio *folio, u64 *p_blkno,
#define OCFS2_MAX_CTXT_PAGES (OCFS2_MAX_CLUSTERSIZE / PAGE_SIZE)
#endif
+#define OCFS2_DIO_WR_MAX_MAP_BYTES (1U << 20) /* 1 MiB */
+
#define OCFS2_MAX_CLUSTERS_PER_PAGE (PAGE_SIZE / OCFS2_MIN_CLUSTERSIZE)
struct ocfs2_unwritten_extent {
@@ -799,8 +801,6 @@ struct ocfs2_write_ctxt {
/* Type of caller. Must be one of buffer, mmap, direct. */
ocfs2_write_type_t w_type;
- struct ocfs2_write_cluster_desc w_desc[OCFS2_MAX_CLUSTERS_PER_PAGE];
-
/*
* This is true if page_size > cluster_size.
*
@@ -850,6 +850,8 @@ struct ocfs2_write_ctxt {
struct list_head w_unwritten_list;
unsigned int w_unwritten_count;
+
+ struct ocfs2_write_cluster_desc w_desc[];
};
void ocfs2_unlock_and_free_folios(struct folio **folios, int num_folios)
@@ -917,17 +919,24 @@ static int ocfs2_alloc_write_ctxt(struct ocfs2_write_ctxt **wcp,
unsigned len, ocfs2_write_type_t type,
struct buffer_head *di_bh)
{
- u32 cend;
+ u32 w_cpos, cend, w_clen;
struct ocfs2_write_ctxt *wc;
+ size_t alloc_size;
+
+ w_cpos = pos >> osb->s_clustersize_bits;
+ cend = (pos + len - 1) >> osb->s_clustersize_bits;
+ w_clen = cend - w_cpos + 1;
- wc = kzalloc_obj(struct ocfs2_write_ctxt, GFP_NOFS);
+ alloc_size = sizeof(struct ocfs2_write_ctxt) +
+ w_clen * sizeof(struct ocfs2_write_cluster_desc);
+
+ wc = kzalloc(alloc_size, GFP_NOFS);
if (!wc)
return -ENOMEM;
- wc->w_cpos = pos >> osb->s_clustersize_bits;
+ wc->w_cpos = w_cpos;
wc->w_first_new_cpos = UINT_MAX;
- cend = (pos + len - 1) >> osb->s_clustersize_bits;
- wc->w_clen = cend - wc->w_cpos + 1;
+ wc->w_clen = w_clen;
get_bh(di_bh);
wc->w_di_bh = di_bh;
wc->w_type = type;
@@ -2218,7 +2227,7 @@ static int ocfs2_dio_wr_get_block(struct inode *inode, sector_t iblock,
struct ocfs2_write_cluster_desc *desc = NULL;
struct ocfs2_dio_write_ctxt *dwc = NULL;
struct buffer_head *di_bh = NULL;
- u64 p_blkno;
+ u64 p_blkno = 0;
unsigned int i_blkbits = inode->i_sb->s_blocksize_bits;
loff_t pos = iblock << i_blkbits;
sector_t endblk = (i_size_read(inode) - 1) >> i_blkbits;
@@ -2358,6 +2367,148 @@ static int ocfs2_dio_wr_get_block(struct inode *inode, sector_t iblock,
return ret;
}
+/* copy from ocfs2_dio_wr_get_block */
+static int ocfs2_dio_wr_map_blocks(struct inode *inode,
+ struct ocfs2_map_block *map, int create)
+{
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct ocfs2_inode_info *oi = OCFS2_I(inode);
+ struct ocfs2_write_ctxt *wc;
+ struct ocfs2_write_cluster_desc *desc = NULL;
+ struct buffer_head *di_bh = NULL;
+ u64 p_blkno;
+ sector_t iblock = map->lblk;
+ unsigned int i_blkbits = inode->i_sb->s_blocksize_bits;
+ loff_t pos = iblock << i_blkbits;
+ sector_t endblk = (i_size_read(inode) - 1) >> i_blkbits;
+ unsigned int total_len = map->len << i_blkbits;
+ unsigned int map_len;
+ unsigned int cont_clusters = 1;
+ int ret = 0, extend = 0, idx;
+
+ /*
+ * map->len is count in ocfs2_iomap_begin according to write
+ * "pos" and "end", we need map twice to return different buffer state:
+ * 1. area in file size, not set NEW;
+ * 2. area out file size, set NEW.
+ *
+ * iblock endblk
+ * |--------|---------|---------|---------
+ * |<-------area in file------->|
+ */
+ if ((iblock <= endblk) &&
+ ((iblock + ((total_len - 1) >> i_blkbits)) > endblk))
+ total_len = (endblk - iblock + 1) << i_blkbits;
+
+ /*
+ * Bound how much we allocate/prepare (and journal) per call. map->len
+ * below still reports only the physically-contiguous prefix to iomap;
+ * iomap calls us again for the remainder.
+ */
+ map_len = min(total_len, OCFS2_DIO_WR_MAX_MAP_BYTES);
+
+ mlog(0, "get block of %llu at %llu:%u req %u\n",
+ inode->i_ino, pos, map_len, total_len);
+
+ /*
+ * Because we need to change file size in ocfs2_iomap_dio_end_io_write(),
+ * or we may need to add it to orphan dir. So can not fall to fast path
+ * while file size will be changed.
+ */
+ if (pos + total_len <= i_size_read(inode)) {
+ /* This is the fast path for re-write. */
+ ret = ocfs2_map_blocks(inode, map, OCFS2_GET_BLOCKS_CREATE);
+ if ((map->flags & OCFS2_MAP_MAPPED) &&
+ !(map->flags & OCFS2_MAP_NEW) && ret == 0)
+ goto out;
+
+ /* Clear state set by ocfs2_map_blocks. */
+ map->flags = 0;
+ } else {
+ extend = 1;
+ }
+
+ ret = ocfs2_inode_lock(inode, &di_bh, 1);
+ if (ret) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ down_write(&oi->ip_alloc_sem);
+
+ if (extend) {
+ if (ocfs2_sparse_alloc(osb))
+ ret = ocfs2_zero_tail(inode, di_bh, pos);
+ else
+ ret = ocfs2_expand_nonsparse_inode(inode, di_bh, pos,
+ map_len, NULL);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto unlock;
+ }
+ }
+
+ ret = ocfs2_write_begin_nolock(inode->i_mapping, pos, map_len,
+ OCFS2_WRITE_DIRECT, NULL,
+ (void **)&wc, di_bh, NULL);
+ if (ret) {
+ mlog_errno(ret);
+ goto unlock;
+ }
+
+ desc = &wc->w_desc[0];
+
+ p_blkno = ocfs2_clusters_to_blocks(inode->i_sb, desc->c_phys);
+ BUG_ON(p_blkno == 0);
+ p_blkno += iblock & (u64)(ocfs2_clusters_to_blocks(inode->i_sb, 1) - 1);
+
+ /*
+ * Calculate physically contiguous clusters by checking descriptor arrays.
+ * This strictly prevents map->len from expanding past non-contiguous physical bounds.
+ */
+ for (idx = 1; idx < wc->w_clen; idx++) {
+ if (wc->w_desc[idx].c_phys == wc->w_desc[idx - 1].c_phys + 1 &&
+ wc->w_desc[idx].c_needs_zero == wc->w_desc[idx - 1].c_needs_zero) {
+ cont_clusters++;
+ } else {
+ break;
+ }
+ }
+ map->pblk = p_blkno;
+ /*
+ * Only report the mapping as UNWRITTEN when the cluster is newly
+ * allocated or was already unwritten (desc->c_needs_zero). Reporting
+ * an already-written cluster as UNWRITTEN makes the iomap direct-io
+ * core zero the sub-block head/tail padding, which destroys existing
+ * data when a sub-block write lands inside a written cluster.
+ */
+ map->flags |= OCFS2_MAP_MAPPED;
+ if (desc->c_needs_zero)
+ map->flags |= OCFS2_MAP_UNWRITTEN;
+ map->len = cont_clusters * ocfs2_clusters_to_blocks(inode->i_sb, 1);
+
+ if (desc->c_needs_zero)
+ map->flags |= OCFS2_MAP_NEW;
+
+ if (iblock > endblk)
+ map->flags |= OCFS2_MAP_NEW;
+
+ map->flags |= OCFS2_MAP_DEFER_COMPLETION;
+
+ ocfs2_free_unwritten_list(inode, &wc->w_unwritten_list);
+ ret = ocfs2_write_end_nolock(inode->i_mapping, pos, map_len, map_len, wc);
+ BUG_ON(ret != map_len);
+ ret = 0;
+
+unlock:
+ up_write(&oi->ip_alloc_sem);
+ ocfs2_inode_unlock(inode, 1);
+ brelse(di_bh);
+
+out:
+ return ret;
+}
+
static int ocfs2_dio_end_io_write(struct inode *inode,
struct ocfs2_dio_write_ctxt *dwc,
loff_t offset,
@@ -2525,6 +2676,8 @@ static int ocfs2_dio_end_io(struct kiocb *iocb,
level = ocfs2_iocb_rw_locked_level(iocb);
ocfs2_rw_unlock(inode, level);
+ /* match iomap rw lock action */
+ ocfs2_iomap_iocb_clear_rw_locked(iocb);
return ret;
}
@@ -2557,6 +2710,12 @@ static ssize_t ocfs2_direct_IO(struct kiocb *iocb, struct iov_iter *iter)
ocfs2_dio_end_io, 0);
}
+static int ocfs2_iomap_alloc(struct inode *inode, struct ocfs2_map_block *map,
+ unsigned int flags)
+{
+ return ocfs2_dio_wr_map_blocks(inode, map, 1);
+}
+
static int ocfs2_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
unsigned int flags, struct iomap *iomap, struct iomap *srcmap)
{
@@ -2564,6 +2723,7 @@ static int ocfs2_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
struct ocfs2_map_block map;
struct ocfs2_inode_info *oi = OCFS2_I(inode);
u8 blkbits = inode->i_blkbits;
+ unsigned int orig_mlen;
if ((offset >> blkbits) > OCFS2_MAX_LOGICAL_BLOCK)
return -EINVAL;
@@ -2575,9 +2735,32 @@ static int ocfs2_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
map.len = min_t(loff_t, (offset + length - 1) >> blkbits,
OCFS2_MAX_LOGICAL_BLOCK) - map.lblk + 1;
map.flags = 0;
+ orig_mlen = map.len;
if (flags & IOMAP_WRITE) {
- /* todo */
+ /*
+ * We check here if the blocks are already allocated, then we
+ * don't need to start a journal txn and we can directly return
+ * the mapping information. This could boost performance
+ * especially in multi-threaded overwrite requests.
+ */
+ if (offset + length <= i_size_read(inode)) {
+ down_read(&oi->ip_alloc_sem);
+ ret = ocfs2_map_blocks(inode, &map, 0);
+ up_read(&oi->ip_alloc_sem);
+ /*
+ * For atomic writes the entire requested length should
+ * be mapped.
+ */
+ if (map.flags & OCFS2_MAP_MAPPED) {
+ if ((!(flags & IOMAP_ATOMIC) && ret > 0) ||
+ (flags & IOMAP_ATOMIC && ret >= orig_mlen)) {
+ goto out;
+ }
+ }
+ map.len = orig_mlen;
+ }
+ ret = ocfs2_iomap_alloc(inode, &map, flags);
} else {
down_read(&oi->ip_alloc_sem);
ret = ocfs2_map_blocks(inode, &map, 0);
@@ -2587,6 +2770,7 @@ static int ocfs2_iomap_begin(struct inode *inode, loff_t offset, loff_t length,
if (ret < 0)
return ret;
+out:
/*
* Before returning to iomap, let's ensure the allocated mapping
* covers the entire requested length for atomic writes.
@@ -2657,6 +2841,191 @@ static int ocfs2_dio_read_end_io(struct kiocb *iocb, ssize_t size, int error,
const struct iomap_dio_ops ocfs2_dio_r_ops = {
.end_io = ocfs2_dio_read_end_io,
};
+
+/* copy from ocfs2_dio_end_io_write */
+static int ocfs2_iomap_dio_end_io_write(struct inode *inode,
+ loff_t offset,
+ ssize_t bytes)
+{
+ struct ocfs2_cached_dealloc_ctxt dealloc;
+ struct ocfs2_extent_tree et;
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
+ struct ocfs2_inode_info *oi = OCFS2_I(inode);
+ struct buffer_head *di_bh = NULL;
+ struct ocfs2_dinode *di;
+ struct ocfs2_alloc_context *data_ac = NULL;
+ struct ocfs2_alloc_context *meta_ac = NULL;
+ handle_t *handle = NULL;
+ loff_t end = offset + bytes;
+ int ret = 0, credits = 0;
+ struct ocfs2_map_block map;
+ unsigned int blkbits = inode->i_blkbits;
+ unsigned int max_blocks;
+ unsigned int ue_cpos = 0, ue_phys = 0, ue_len = 0;
+ unsigned int curr_lblk, end_lblk;
+
+ map.lblk = offset >> blkbits;
+ max_blocks = (bytes + offset) >> osb->s_clustersize_bits;
+
+ ocfs2_init_dealloc_ctxt(&dealloc);
+
+ ret = ocfs2_inode_lock(inode, &di_bh, 1);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ }
+
+ down_write(&oi->ip_alloc_sem);
+
+ di = (struct ocfs2_dinode *)di_bh->b_data;
+
+ ocfs2_init_dinode_extent_tree(&et, INODE_CACHE(inode), di_bh);
+
+ /* Attach dealloc with extent tree in case that we may reuse extents
+ * which are already unlinked from current extent tree due to extent
+ * rotation and merging.
+ */
+ et.et_dealloc = &dealloc;
+
+ ret = ocfs2_lock_allocators(inode, &et, 0, (bytes >> osb->s_clustersize_bits)*2,
+ &data_ac, &meta_ac);
+ if (ret) {
+ mlog_errno(ret);
+ goto unlock;
+ }
+
+ credits = ocfs2_calc_extend_credits(inode->i_sb, &di->id2.i_list);
+
+ handle = ocfs2_start_trans(osb, credits);
+ if (IS_ERR(handle)) {
+ ret = PTR_ERR(handle);
+ mlog_errno(ret);
+ goto unlock;
+ }
+ ret = ocfs2_journal_access_di(handle, INODE_CACHE(inode), di_bh,
+ OCFS2_JOURNAL_ACCESS_WRITE);
+ if (ret) {
+ mlog_errno(ret);
+ goto commit;
+ }
+
+ curr_lblk = offset >> blkbits;
+ /*
+ * Round the end up so the final partial block (sub-block direct I/O)
+ * is included; otherwise the last, partially-written cluster is left
+ * unwritten and reads back as zero.
+ */
+ end_lblk = (offset + bytes + (1 << blkbits) - 1) >> blkbits;
+ while (ret >= 0 && curr_lblk < end_lblk) {
+ memset(&map, 0, sizeof(map));
+ map.lblk += curr_lblk;
+ map.len = end_lblk - curr_lblk;
+
+ ret = ocfs2_assure_trans_credits(handle, credits);
+ if (ret < 0) {
+ mlog_errno(ret);
+ break;
+ }
+
+ ret = ocfs2_map_blocks(inode, &map, 0);
+ if (ret < 0) {
+ mlog_errno(ret);
+ break;
+ }
+ if (ret == 0)
+ break;
+
+ if (map.flags & OCFS2_MAP_UNWRITTEN) {
+ ue_cpos = ocfs2_blocks_to_clusters(inode->i_sb, map.lblk);
+ ue_phys = ocfs2_blocks_to_clusters(inode->i_sb, map.pblk);
+ ue_len = ocfs2_clusters_for_blocks(inode->i_sb,
+ map.lblk + map.len) - ue_cpos;
+
+ ret = ocfs2_mark_extent_written(inode, &et, handle,
+ ue_cpos, ue_len,
+ ue_phys,
+ meta_ac, &dealloc);
+ if (ret < 0) {
+ mlog_errno(ret);
+ break;
+ }
+ }
+ curr_lblk += map.len;
+ }
+
+ if (end > i_size_read(inode)) {
+ ret = ocfs2_set_inode_size(handle, inode, di_bh, end);
+ if (ret < 0)
+ mlog_errno(ret);
+ }
+
+commit:
+ ocfs2_commit_trans(osb, handle);
+
+unlock:
+ up_write(&oi->ip_alloc_sem);
+
+ if (data_ac)
+ ocfs2_free_alloc_context(data_ac);
+ if (meta_ac)
+ ocfs2_free_alloc_context(meta_ac);
+
+ down_write(&oi->ip_alloc_sem);
+ if (!ret && (di->i_flags & cpu_to_le32(OCFS2_DIO_ORPHANED_FL))) {
+ ret = ocfs2_del_inode_from_orphan(osb, inode, di_bh, 0, 0);
+ if (ret < 0)
+ mlog_errno(ret);
+ }
+ up_write(&oi->ip_alloc_sem);
+ ocfs2_inode_unlock(inode, 1);
+ brelse(di_bh);
+
+out:
+ ocfs2_run_deallocs(osb, &dealloc);
+ return ret;
+}
+
+static int ocfs2_dio_write_end_io(struct kiocb *iocb, ssize_t size, int error,
+ unsigned int flags)
+{
+ struct inode *inode = file_inode(iocb->ki_filp);
+ loff_t offset = iocb->ki_pos;
+ int level;
+ int ret = 0;
+
+ if (error) {
+ mlog_ratelimited(ML_ERROR, "Direct IO failed, bytes = %lld errno:%d",
+ (long long)size, error);
+ goto bail;
+ }
+
+ BUG_ON(!ocfs2_iomap_iocb_is_rw_locked(iocb));
+
+
+ if (size && ((flags & IOMAP_DIO_UNWRITTEN) ||
+ (offset + size > i_size_read(inode)))) {
+ ret = ocfs2_iomap_dio_end_io_write(inode, offset, size);
+ if (ret < 0)
+ mlog_errno(ret);
+ }
+
+ level = ocfs2_iomap_iocb_rw_locked_level(iocb);
+
+ /* sync dio unlock job done in .read_iter or .write_iter */
+ if (ocfs2_iomap_iocb_is_rw_locked(iocb))
+ ocfs2_rw_unlock(inode, level);
+
+ ocfs2_iocb_clear_rw_locked(iocb);
+ ocfs2_iomap_iocb_clear_rw_locked(iocb);
+
+bail:
+ return error;
+}
+
+const struct iomap_dio_ops ocfs2_dio_w_ops = {
+ .end_io = ocfs2_dio_write_end_io,
+};
+
const struct address_space_operations ocfs2_aops = {
.dirty_folio = block_dirty_folio,
.read_folio = ocfs2_read_folio,
diff --git a/fs/ocfs2/buffer_head_io.c b/fs/ocfs2/buffer_head_io.c
index 493f2209cca5..03906ab737ec 100644
--- a/fs/ocfs2/buffer_head_io.c
+++ b/fs/ocfs2/buffer_head_io.c
@@ -332,6 +332,8 @@ int ocfs2_read_blocks(struct ocfs2_caching_info *ci, u64 block, int nr,
wait_on_buffer(bh);
put_bh(bh);
bhs[i] = NULL;
+ } else if (bh && buffer_uptodate(bh)) {
+ clear_buffer_uptodate(bh);
}
continue;
}
@@ -360,11 +362,8 @@ int ocfs2_read_blocks(struct ocfs2_caching_info *ci, u64 block, int nr,
BUG_ON(buffer_jbd(bh));
clear_buffer_needs_validate(bh);
status = validate(sb, bh);
- if (status) {
- if (buffer_uptodate(bh))
- clear_buffer_uptodate(bh);
+ if (status)
goto read_failure;
- }
}
}
diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index e879312ff86b..f84e5e3ed391 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -48,6 +48,7 @@
#include "quota.h"
#include "refcounttree.h"
#include "ocfs2_trace.h"
+#include "namei.h"
#include "buffer_head_io.h"
@@ -2378,6 +2379,7 @@ static int ocfs2_prepare_inode_for_write(struct file *file,
static bool ocfs2_should_use_dio(struct kiocb *iocb, struct iov_iter *iter,
struct inode *inode)
{
+ struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
unsigned int dio_align = bdev_logical_block_size(inode->i_sb->s_bdev);
/*
@@ -2387,6 +2389,11 @@ static bool ocfs2_should_use_dio(struct kiocb *iocb, struct iov_iter *iter,
if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
return false;
+ /* Fallback to buffered I/O if we do not support append dio. */
+ if (iocb->ki_pos + iter->count > i_size_read(inode) &&
+ !ocfs2_supports_append_dio(osb))
+ return false;
+
/*
* Allow Direct I/O for any write requests aligned to the underlying
* logical sector size (e.g., 512 bytes).
@@ -2415,6 +2422,8 @@ static ssize_t ocfs2_file_write_iter(struct kiocb *iocb,
i_size_read(inode) ? 1 : 0);
int direct_io = iocb->ki_flags & IOCB_DIRECT ? 1 : 0;
int nowait = iocb->ki_flags & IOCB_NOWAIT ? 1 : 0;
+ int dio_flags = 0;
+ ssize_t buffered;
trace_ocfs2_file_write_iter(inode, file, file->f_path.dentry,
(unsigned long long)OCFS2_I(inode)->ip_blkno,
@@ -2434,7 +2443,9 @@ static ssize_t ocfs2_file_write_iter(struct kiocb *iocb,
} else
inode_lock(inode);
+ /* check the comments in ocfs2_file_read_iter() */
ocfs2_iocb_init_rw_locked(iocb);
+ ocfs2_iomap_iocb_init_rw_locked(iocb);
/*
* Concurrent O_DIRECT writes are allowed with
@@ -2501,8 +2512,46 @@ static ssize_t ocfs2_file_write_iter(struct kiocb *iocb,
/* communicate with ocfs2_dio_end_io */
ocfs2_iocb_set_rw_locked(iocb, rw_level);
+ /* communicate with ocfs2_dio_write_end_io */
+ ocfs2_iomap_iocb_set_rw_locked(iocb, rw_level);
+
+ if (direct_io && ocfs2_should_use_dio(iocb, from, inode)) {
+ if (ocfs2_clusters_for_bytes(inode->i_sb, iocb->ki_pos + count) >
+ ocfs2_clusters_for_bytes(inode->i_sb, i_size_read(inode))) {
+ /*
+ * when we are going to alloc extents beyond file size, add the
+ * inode to orphan dir, so we can recall those spaces when
+ * system crashed during write.
+ */
+ ret = ocfs2_add_inode_to_orphan(osb, inode);
+ if (ret < 0) {
+ mlog_errno(ret);
+ goto out;
+ }
+ dio_flags = IOMAP_DIO_FORCE_WAIT;
+ }
+
+ written = iomap_dio_rw(iocb, from, &ocfs2_iomap_ops, &ocfs2_dio_w_ops,
+ dio_flags, NULL, 0);
+ /*
+ * iomap_dio_rw() returns -ENOTBLK when it could not invalidate
+ * the page cache for the DIO range (e.g. racing buffered/mmap
+ * I/O on the same file, as exercised by generic/095). Fall back
+ * to a buffered write for the remaining data, the same way
+ * ext4/xfs do, instead of leaking -ENOTBLK to userspace.
+ */
+ if (written == -ENOTBLK)
+ written = 0;
+ if (written >= 0 && iov_iter_count(from)) {
+ iocb->ki_flags &= ~IOCB_DIRECT;
+ buffered = __generic_file_write_iter(iocb, from);
+ written = direct_write_fallback(iocb, from, written, buffered);
+ }
+ } else {
+ iocb->ki_flags &= ~IOCB_DIRECT;
+ written = __generic_file_write_iter(iocb, from);
+ }
- written = __generic_file_write_iter(iocb, from);
/* buffered aio wouldn't have proper lock coverage today */
BUG_ON(written == -EIOCBQUEUED && !direct_io);
@@ -2546,8 +2595,10 @@ static ssize_t ocfs2_file_write_iter(struct kiocb *iocb,
if (saved_ki_complete)
xchg(&iocb->ki_complete, saved_ki_complete);
- if (rw_level != -1)
+ if (rw_level != -1) {
ocfs2_rw_unlock(inode, rw_level);
+ ocfs2_iomap_iocb_clear_rw_locked(iocb);
+ }
out_mutex:
inode_unlock(inode);
diff --git a/fs/ocfs2/ocfs2.h b/fs/ocfs2/ocfs2.h
index 9397947583fb..7a7a2ecdaeaf 100644
--- a/fs/ocfs2/ocfs2.h
+++ b/fs/ocfs2/ocfs2.h
@@ -551,6 +551,7 @@ struct ocfs2_map_block {
extern const struct iomap_ops ocfs2_iomap_ops;
extern const struct iomap_dio_ops ocfs2_dio_r_ops;
+extern const struct iomap_dio_ops ocfs2_dio_w_ops;
/* Flags used by ocfs2_map_blocks() */
#define OCFS2_GET_BLOCKS_CREATE (0x0001)
--
2.54.0