@@ -2007,10 +2007,10 @@ iomap_writepages(struct address_space *mapping, struct writeback_control *wbc,
}
EXPORT_SYMBOL_GPL(iomap_writepages);
-static int __init iomap_init(void)
+static int __init iomap_pagecache_init(void)
{
return bioset_init(&iomap_ioend_bioset, 4 * (PAGE_SIZE / SECTOR_SIZE),
offsetof(struct iomap_ioend, io_bio),
BIOSET_NEED_BVECS);
}
-fs_initcall(iomap_init);
+fs_initcall(iomap_pagecache_init);
@@ -11,6 +11,7 @@
#include <linux/iomap.h>
#include <linux/backing-dev.h>
#include <linux/uio.h>
+#include <linux/set_memory.h>
#include <linux/task_io_accounting_ops.h>
#include "trace.h"
@@ -27,6 +28,13 @@
#define IOMAP_DIO_WRITE (1U << 30)
#define IOMAP_DIO_DIRTY (1U << 31)
+/*
+ * Used for sub block zeroing in iomap_dio_zero()
+ */
+#define ZERO_PAGE_64K_SIZE (65536)
+#define ZERO_PAGE_64K_ORDER (get_order(ZERO_PAGE_64K_SIZE))
+static struct page *zero_page_64k;
+
struct iomap_dio {
struct kiocb *iocb;
const struct iomap_dio_ops *dops;
@@ -236,9 +244,13 @@ static void iomap_dio_zero(const struct iomap_iter *iter, struct iomap_dio *dio,
loff_t pos, unsigned len)
{
struct inode *inode = file_inode(dio->iocb->ki_filp);
- struct page *page = ZERO_PAGE(0);
struct bio *bio;
+ /*
+ * Max block size supported is 64k
+ */
+ WARN_ON_ONCE(len > ZERO_PAGE_64K_SIZE);
+
bio = iomap_dio_alloc_bio(iter, dio, 1, REQ_OP_WRITE | REQ_SYNC | REQ_IDLE);
fscrypt_set_bio_crypt_ctx(bio, inode, pos >> inode->i_blkbits,
GFP_KERNEL);
@@ -246,7 +258,7 @@ static void iomap_dio_zero(const struct iomap_iter *iter, struct iomap_dio *dio,
bio->bi_private = dio;
bio->bi_end_io = iomap_dio_bio_end_io;
- __bio_add_page(bio, page, len, 0);
+ __bio_add_page(bio, zero_page_64k, len, 0);
iomap_dio_submit_bio(iter, dio, bio, pos);
}
@@ -753,3 +765,17 @@ iomap_dio_rw(struct kiocb *iocb, struct iov_iter *iter,
return iomap_dio_complete(dio);
}
EXPORT_SYMBOL_GPL(iomap_dio_rw);
+
+static int __init iomap_dio_init(void)
+{
+ zero_page_64k = alloc_pages(GFP_KERNEL | __GFP_ZERO,
+ ZERO_PAGE_64K_ORDER);
+
+ if (!zero_page_64k)
+ return -ENOMEM;
+
+ set_memory_ro((unsigned long)page_address(zero_page_64k),
+ 1U << ZERO_PAGE_64K_ORDER);
+ return 0;
+}
+fs_initcall(iomap_dio_init);