iomap: pass an iomap_iter to various buffered I/O helpers

Pass the iomap_iter structure instead of individual parameters to
various internal helpers for buffered I/O.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <djwong@kernel.org>
Signed-off-by: Darrick J. Wong <djwong@kernel.org>

diff --git a/fs/iomap/buffered-io.c b/fs/iomap/buffered-io.c
index 59db1e3..d6d1fd0 100644 (file)
--- a/fs/iomap/buffered-io.c
+++ b/fs/iomap/buffered-io.c
@@ -205,10 +205,11 @@ struct iomap_readpage_ctx {
        struct readahead_control *rac;
 };
 
-static loff_t iomap_read_inline_data(struct inode *inode, struct page *page,
-               const struct iomap *iomap)
+static loff_t iomap_read_inline_data(struct iomap_iter *iter,
+               struct page *page)
 {
-       size_t size = i_size_read(inode) - iomap->offset;
+       struct iomap *iomap = iomap_iter_srcmap(iter);
+       size_t size = i_size_read(iter->inode) - iomap->offset;
        size_t poff = offset_in_page(iomap->offset);
        void *addr;
 
@@ -223,7 +224,7 @@ static loff_t iomap_read_inline_data(struct inode *inode, struct page *page,
        if (WARN_ON_ONCE(size > iomap->length))
                return -EIO;
        if (poff > 0)
-               iomap_page_create(inode, page);
+               iomap_page_create(iter->inode, page);
 
        addr = kmap_local_page(page) + poff;
        memcpy(addr, iomap->inline_data, size);
@@ -233,12 +234,14 @@ static loff_t iomap_read_inline_data(struct inode *inode, struct page *page,
        return PAGE_SIZE - poff;
 }
 
-static inline bool iomap_block_needs_zeroing(struct inode *inode,
-               struct iomap *iomap, loff_t pos)
+static inline bool iomap_block_needs_zeroing(struct iomap_iter *iter,
+               loff_t pos)
 {
-       return iomap->type != IOMAP_MAPPED ||
-               (iomap->flags & IOMAP_F_NEW) ||
-               pos >= i_size_read(inode);
+       struct iomap *srcmap = iomap_iter_srcmap(iter);
+
+       return srcmap->type != IOMAP_MAPPED ||
+               (srcmap->flags & IOMAP_F_NEW) ||
+               pos >= i_size_read(iter->inode);
 }
 
 static loff_t iomap_readpage_iter(struct iomap_iter *iter,
@@ -254,8 +257,7 @@ static loff_t iomap_readpage_iter(struct iomap_iter *iter,
        sector_t sector;
 
        if (iomap->type == IOMAP_INLINE)
-               return min(iomap_read_inline_data(iter->inode, page, iomap),
-                                                 length);
+               return min(iomap_read_inline_data(iter, page), length);
 
        /* zero post-eof blocks as the page may be mapped */
        iop = iomap_page_create(iter->inode, page);
@@ -263,7 +265,7 @@ static loff_t iomap_readpage_iter(struct iomap_iter *iter,
        if (plen == 0)
                goto done;
 
-       if (iomap_block_needs_zeroing(iter->inode, iomap, pos)) {
+       if (iomap_block_needs_zeroing(iter, pos)) {
                zero_user(page, poff, plen);
                iomap_set_range_uptodate(page, poff, plen);
                goto done;
@@ -538,12 +540,12 @@ iomap_read_page_sync(loff_t block_start, struct page *page, unsigned poff,
        return submit_bio_wait(&bio);
 }
 
-static int
-__iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, int flags,
-               struct page *page, struct iomap *srcmap)
+static int __iomap_write_begin(struct iomap_iter *iter, loff_t pos,
+               unsigned len, int flags, struct page *page)
 {
-       struct iomap_page *iop = iomap_page_create(inode, page);
-       loff_t block_size = i_blocksize(inode);
+       struct iomap *srcmap = iomap_iter_srcmap(iter);
+       struct iomap_page *iop = iomap_page_create(iter->inode, page);
+       loff_t block_size = i_blocksize(iter->inode);
        loff_t block_start = round_down(pos, block_size);
        loff_t block_end = round_up(pos + len, block_size);
        unsigned from = offset_in_page(pos), to = from + len, poff, plen;
@@ -553,7 +555,7 @@ __iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, int flags,
        ClearPageError(page);
 
        do {
-               iomap_adjust_read_range(inode, iop, &block_start,
+               iomap_adjust_read_range(iter->inode, iop, &block_start,
                                block_end - block_start, &poff, &plen);
                if (plen == 0)
                        break;
@@ -563,7 +565,7 @@ __iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, int flags,
                    (to <= poff || to >= poff + plen))
                        continue;
 
-               if (iomap_block_needs_zeroing(inode, srcmap, block_start)) {
+               if (iomap_block_needs_zeroing(iter, block_start)) {
                        if (WARN_ON_ONCE(flags & IOMAP_WRITE_F_UNSHARE))
                                return -EIO;
                        zero_user_segments(page, poff, from, to, poff + plen);
@@ -579,55 +581,54 @@ __iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, int flags,
        return 0;
 }
 
-static int iomap_write_begin_inline(struct inode *inode,
-               struct page *page, struct iomap *srcmap)
+static int iomap_write_begin_inline(struct iomap_iter *iter,
+               struct page *page)
 {
        int ret;
 
        /* needs more work for the tailpacking case; disable for now */
-       if (WARN_ON_ONCE(srcmap->offset != 0))
+       if (WARN_ON_ONCE(iomap_iter_srcmap(iter)->offset != 0))
                return -EIO;
-       ret = iomap_read_inline_data(inode, page, srcmap);
+       ret = iomap_read_inline_data(iter, page);
        if (ret < 0)
                return ret;
        return 0;
 }
 
-static int
-iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, unsigned flags,
-               struct page **pagep, struct iomap *iomap, struct iomap *srcmap)
+static int iomap_write_begin(struct iomap_iter *iter, loff_t pos, unsigned len,
+               unsigned flags, struct page **pagep)
 {
-       const struct iomap_page_ops *page_ops = iomap->page_ops;
+       const struct iomap_page_ops *page_ops = iter->iomap.page_ops;
+       struct iomap *srcmap = iomap_iter_srcmap(iter);
        struct page *page;
        int status = 0;
 
-       BUG_ON(pos + len > iomap->offset + iomap->length);
-       if (srcmap != iomap)
+       BUG_ON(pos + len > iter->iomap.offset + iter->iomap.length);
+       if (srcmap != &iter->iomap)
                BUG_ON(pos + len > srcmap->offset + srcmap->length);
 
        if (fatal_signal_pending(current))
                return -EINTR;
 
        if (page_ops && page_ops->page_prepare) {
-               status = page_ops->page_prepare(inode, pos, len);
+               status = page_ops->page_prepare(iter->inode, pos, len);
                if (status)
                        return status;
        }
 
-       page = grab_cache_page_write_begin(inode->i_mapping, pos >> PAGE_SHIFT,
-                       AOP_FLAG_NOFS);
+       page = grab_cache_page_write_begin(iter->inode->i_mapping,
+                               pos >> PAGE_SHIFT, AOP_FLAG_NOFS);
        if (!page) {
                status = -ENOMEM;
                goto out_no_page;
        }
 
        if (srcmap->type == IOMAP_INLINE)
-               status = iomap_write_begin_inline(inode, page, srcmap);
-       else if (iomap->flags & IOMAP_F_BUFFER_HEAD)
+               status = iomap_write_begin_inline(iter, page);
+       else if (srcmap->flags & IOMAP_F_BUFFER_HEAD)
                status = __block_write_begin_int(page, pos, len, NULL, srcmap);
        else
-               status = __iomap_write_begin(inode, pos, len, flags, page,
-                               srcmap);
+               status = __iomap_write_begin(iter, pos, len, flags, page);
 
        if (unlikely(status))
                goto out_unlock;
@@ -638,11 +639,11 @@ iomap_write_begin(struct inode *inode, loff_t pos, unsigned len, unsigned flags,
 out_unlock:
        unlock_page(page);
        put_page(page);
-       iomap_write_failed(inode, pos, len);
+       iomap_write_failed(iter->inode, pos, len);
 
 out_no_page:
        if (page_ops && page_ops->page_done)
-               page_ops->page_done(inode, pos, 0, NULL);
+               page_ops->page_done(iter->inode, pos, 0, NULL);
        return status;
 }
 
@@ -669,9 +670,10 @@ static size_t __iomap_write_end(struct inode *inode, loff_t pos, size_t len,
        return copied;
 }
 
-static size_t iomap_write_end_inline(struct inode *inode, struct page *page,
-               struct iomap *iomap, loff_t pos, size_t copied)
+static size_t iomap_write_end_inline(struct iomap_iter *iter, struct page *page,
+               loff_t pos, size_t copied)
 {
+       struct iomap *iomap = &iter->iomap;
        void *addr;
 
        WARN_ON_ONCE(!PageUptodate(page));
@@ -682,26 +684,26 @@ static size_t iomap_write_end_inline(struct inode *inode, struct page *page,
        memcpy(iomap_inline_data(iomap, pos), addr, copied);
        kunmap_local(addr);
 
-       mark_inode_dirty(inode);
+       mark_inode_dirty(iter->inode);
        return copied;
 }
 
 /* Returns the number of bytes copied.  May be 0.  Cannot be an errno. */
-static size_t iomap_write_end(struct inode *inode, loff_t pos, size_t len,
-               size_t copied, struct page *page, struct iomap *iomap,
-               struct iomap *srcmap)
+static size_t iomap_write_end(struct iomap_iter *iter, loff_t pos, size_t len,
+               size_t copied, struct page *page)
 {
-       const struct iomap_page_ops *page_ops = iomap->page_ops;
-       loff_t old_size = inode->i_size;
+       const struct iomap_page_ops *page_ops = iter->iomap.page_ops;
+       struct iomap *srcmap = iomap_iter_srcmap(iter);
+       loff_t old_size = iter->inode->i_size;
        size_t ret;
 
        if (srcmap->type == IOMAP_INLINE) {
-               ret = iomap_write_end_inline(inode, page, iomap, pos, copied);
+               ret = iomap_write_end_inline(iter, page, pos, copied);
        } else if (srcmap->flags & IOMAP_F_BUFFER_HEAD) {
-               ret = block_write_end(NULL, inode->i_mapping, pos, len, copied,
-                               page, NULL);
+               ret = block_write_end(NULL, iter->inode->i_mapping, pos, len,
+                               copied, page, NULL);
        } else {
-               ret = __iomap_write_end(inode, pos, len, copied, page);
+               ret = __iomap_write_end(iter->inode, pos, len, copied, page);
        }
 
        /*
@@ -710,26 +712,24 @@ static size_t iomap_write_end(struct inode *inode, loff_t pos, size_t len,
         * preferably after I/O completion so that no stale data is exposed.
         */
        if (pos + ret > old_size) {
-               i_size_write(inode, pos + ret);
-               iomap->flags |= IOMAP_F_SIZE_CHANGED;
+               i_size_write(iter->inode, pos + ret);
+               iter->iomap.flags |= IOMAP_F_SIZE_CHANGED;
        }
        unlock_page(page);
 
        if (old_size < pos)
-               pagecache_isize_extended(inode, old_size, pos);
+               pagecache_isize_extended(iter->inode, old_size, pos);
        if (page_ops && page_ops->page_done)
-               page_ops->page_done(inode, pos, ret, page);
+               page_ops->page_done(iter->inode, pos, ret, page);
        put_page(page);
 
        if (ret < len)
-               iomap_write_failed(inode, pos, len);
+               iomap_write_failed(iter->inode, pos, len);
        return ret;
 }
 
 static loff_t iomap_write_iter(struct iomap_iter *iter, struct iov_iter *i)
 {
-       struct iomap *srcmap = iomap_iter_srcmap(iter);
-       struct iomap *iomap = &iter->iomap;
        loff_t length = iomap_length(iter);
        loff_t pos = iter->pos;
        ssize_t written = 0;
@@ -759,8 +759,7 @@ again:
                        break;
                }
 
-               status = iomap_write_begin(iter->inode, pos, bytes, 0, &page,
-                                          iomap, srcmap);
+               status = iomap_write_begin(iter, pos, bytes, 0, &page);
                if (unlikely(status))
                        break;
 
@@ -769,8 +768,7 @@ again:
 
                copied = copy_page_from_iter_atomic(page, offset, bytes, i);
 
-               status = iomap_write_end(iter->inode, pos, bytes, copied, page,
-                                        iomap, srcmap);
+               status = iomap_write_end(iter, pos, bytes, copied, page);
 
                if (unlikely(copied != status))
                        iov_iter_revert(i, copied - status);
@@ -838,13 +836,12 @@ static loff_t iomap_unshare_iter(struct iomap_iter *iter)
                unsigned long bytes = min_t(loff_t, PAGE_SIZE - offset, length);
                struct page *page;
 
-               status = iomap_write_begin(iter->inode, pos, bytes,
-                               IOMAP_WRITE_F_UNSHARE, &page, iomap, srcmap);
+               status = iomap_write_begin(iter, pos, bytes,
+                               IOMAP_WRITE_F_UNSHARE, &page);
                if (unlikely(status))
                        return status;
 
-               status = iomap_write_end(iter->inode, pos, bytes, bytes, page, iomap,
-                               srcmap);
+               status = iomap_write_end(iter, pos, bytes, bytes, page);
                if (WARN_ON_ONCE(status == 0))
                        return -EIO;
 
@@ -878,22 +875,21 @@ iomap_file_unshare(struct inode *inode, loff_t pos, loff_t len,
 }
 EXPORT_SYMBOL_GPL(iomap_file_unshare);
 
-static s64 iomap_zero(struct inode *inode, loff_t pos, u64 length,
-               struct iomap *iomap, struct iomap *srcmap)
+static s64 __iomap_zero_iter(struct iomap_iter *iter, loff_t pos, u64 length)
 {
        struct page *page;
        int status;
        unsigned offset = offset_in_page(pos);
        unsigned bytes = min_t(u64, PAGE_SIZE - offset, length);
 
-       status = iomap_write_begin(inode, pos, bytes, 0, &page, iomap, srcmap);
+       status = iomap_write_begin(iter, pos, bytes, 0, &page);
        if (status)
                return status;
 
        zero_user(page, offset, bytes);
        mark_page_accessed(page);
 
-       return iomap_write_end(inode, pos, bytes, bytes, page, iomap, srcmap);
+       return iomap_write_end(iter, pos, bytes, bytes, page);
 }
 
 static loff_t iomap_zero_iter(struct iomap_iter *iter, bool *did_zero)
@@ -914,8 +910,7 @@ static loff_t iomap_zero_iter(struct iomap_iter *iter, bool *did_zero)
                if (IS_DAX(iter->inode))
                        bytes = dax_iomap_zero(pos, length, iomap);
                else
-                       bytes = iomap_zero(iter->inode, pos, length, iomap,
-                                          srcmap);
+                       bytes = __iomap_zero_iter(iter, pos, length);
                if (bytes < 0)
                        return bytes;