2 files changed, 57 insertions, 191 deletions

diff --git a/mm/filemap.h b/mm/filemap.h
index c2d0546a57eb..13793ba0ce17 100644
--- a/mm/filemap.h
+++ b/mm/filemap.h
@@ -15,7 +15,7 @@
 #include <linux/config.h>
 #include <asm/uaccess.h>
 
-extern size_t
+size_t
 __filemap_copy_from_user_iovec(char *vaddr,
                                const struct iovec *iov,
                                size_t base,
diff --git a/mm/filemap_xip.c b/mm/filemap_xip.c
index 7d63acd48817..3b6e384b98a6 100644
--- a/mm/filemap_xip.c
+++ b/mm/filemap_xip.c
@@ -114,83 +114,28 @@ out:
                 file_accessed(filp);
 }
 
-/*
- * This is the "read()" routine for all filesystems
- * that uses the get_xip_page address space operation.
- */
-static ssize_t
-__xip_file_aio_read(struct kiocb *iocb, const struct iovec *iov,
-                unsigned long nr_segs, loff_t *ppos)
-{
-        struct file *filp = iocb->ki_filp;
-        ssize_t retval;
-        unsigned long seg;
-        size_t count;
-
-        count = 0;
-        for (seg = 0; seg < nr_segs; seg++) {
-                const struct iovec *iv = &iov[seg];
-
-                /*
-                 * If any segment has a negative length, or the cumulative
-                 * length ever wraps negative then return -EINVAL.
-                 */
-                count += iv->iov_len;
-                if (unlikely((ssize_t)(count|iv->iov_len) < 0))
-                        return -EINVAL;
-                if (access_ok(VERIFY_WRITE, iv->iov_base, iv->iov_len))
-                        continue;
-                if (seg == 0)
-                        return -EFAULT;
-                nr_segs = seg;
-                count -= iv->iov_len;   /* This segment is no good */
-                break;
-        }
-
-        retval = 0;
-        if (count) {
-                for (seg = 0; seg < nr_segs; seg++) {
-                        read_descriptor_t desc;
-
-                        desc.written = 0;
-                        desc.arg.buf = iov[seg].iov_base;
-                        desc.count = iov[seg].iov_len;
-                        if (desc.count == 0)
-                                continue;
-                        desc.error = 0;
-                        do_xip_mapping_read(filp->f_mapping, &filp->f_ra, filp,
-                                            ppos, &desc, file_read_actor);
-                        retval += desc.written;
-                        if (!retval) {
-                                retval = desc.error;
-                                break;
-                        }
-                }
-        }
-        return retval;
-}
-
 ssize_t
-xip_file_aio_read(struct kiocb *iocb, char __user *buf, size_t count,
-                  loff_t pos)
+xip_file_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos)
 {
-        struct iovec local_iov = { .iov_base = buf, .iov_len = count };
+        read_descriptor_t desc;
 
-        BUG_ON(iocb->ki_pos != pos);
-        return __xip_file_aio_read(iocb, &local_iov, 1, &iocb->ki_pos);
-}
-EXPORT_SYMBOL_GPL(xip_file_aio_read);
+        if (!access_ok(VERIFY_WRITE, buf, len))
+                return -EFAULT;
 
-ssize_t
-xip_file_readv(struct file *filp, const struct iovec *iov,
-               unsigned long nr_segs, loff_t *ppos)
-{
-        struct kiocb kiocb;
+        desc.written = 0;
+        desc.arg.buf = buf;
+        desc.count = len;
+        desc.error = 0;
 
-        init_sync_kiocb(&kiocb, filp);
-        return __xip_file_aio_read(&kiocb, iov, nr_segs, ppos);
+        do_xip_mapping_read(filp->f_mapping, &filp->f_ra, filp,
+                            ppos, &desc, file_read_actor);
+
+        if (desc.written)
+                return desc.written;
+        else
+                return desc.error;
 }
-EXPORT_SYMBOL_GPL(xip_file_readv);
+EXPORT_SYMBOL_GPL(xip_file_read);
 
 ssize_t
 xip_file_sendfile(struct file *in_file, loff_t *ppos,
@@ -326,25 +271,19 @@ int xip_file_mmap(struct file * file, struct vm_area_struct * vma)
 EXPORT_SYMBOL_GPL(xip_file_mmap);
 
 static ssize_t
-do_xip_file_write(struct kiocb *iocb, const struct iovec *iov,
-                  unsigned long nr_segs, loff_t pos, loff_t *ppos,
-                  size_t count)
+__xip_file_write(struct file *filp, const char __user *buf,
+                  size_t count, loff_t pos, loff_t *ppos)
 {
-        struct file *file = iocb->ki_filp;
-        struct address_space * mapping = file->f_mapping;
+        struct address_space * mapping = filp->f_mapping;
         struct address_space_operations *a_ops = mapping->a_ops;
         struct inode    *inode = mapping->host;
         long            status = 0;
         struct page     *page;
         size_t          bytes;
-        const struct iovec *cur_iov = iov; /* current iovec */
-        size_t          iov_base = 0;      /* offset in the current iovec */
-        char __user     *buf;
         ssize_t         written = 0;
 
         BUG_ON(!mapping->a_ops->get_xip_page);
 
-        buf = iov->iov_base;
         do {
                 unsigned long index;
                 unsigned long offset;
@@ -365,15 +304,14 @@ do_xip_file_write(struct kiocb *iocb, const struct iovec *iov,
                 fault_in_pages_readable(buf, bytes);
 
                 page = a_ops->get_xip_page(mapping,
-                                                    index*(PAGE_SIZE/512), 0);
+                                           index*(PAGE_SIZE/512), 0);
                 if (IS_ERR(page) && (PTR_ERR(page) == -ENODATA)) {
                         /* we allocate a new page unmap it */
                         page = a_ops->get_xip_page(mapping,
-                                index*(PAGE_SIZE/512), 1);
+                                                   index*(PAGE_SIZE/512), 1);
                         if (!IS_ERR(page))
-                        /* unmap page at pgoff from all other vmas */
-                        __xip_unmap(mapping, index);
-
+                                /* unmap page at pgoff from all other vmas */
+                                __xip_unmap(mapping, index);
                 }
 
                 if (IS_ERR(page)) {
@@ -383,12 +321,7 @@ do_xip_file_write(struct kiocb *iocb, const struct iovec *iov,
 
                 BUG_ON(!PageUptodate(page));
 
-                if (likely(nr_segs == 1))
-                        copied = filemap_copy_from_user(page, offset,
-                                                        buf, bytes);
-                else
-                        copied = filemap_copy_from_user_iovec(page, offset,
-                                                cur_iov, iov_base, bytes);
+                copied = filemap_copy_from_user(page, offset, buf, bytes);
                 flush_dcache_page(page);
                 if (likely(copied > 0)) {
                         status = copied;
@@ -398,9 +331,6 @@ do_xip_file_write(struct kiocb *iocb, const struct iovec *iov,
                                 count -= status;
                                 pos += status;
                                 buf += status;
-                                if (unlikely(nr_segs > 1))
-                                        filemap_set_next_iovec(&cur_iov,
-                                                        &iov_base, status);
                         }
                 }
                 if (unlikely(copied != bytes))
@@ -422,110 +352,52 @@ do_xip_file_write(struct kiocb *iocb, const struct iovec *iov,
         return written ? written : status;
 }
 
-static ssize_t
-xip_file_aio_write_nolock(struct kiocb *iocb, const struct iovec *iov,
-                                unsigned long nr_segs, loff_t *ppos)
+ssize_t
+xip_file_write(struct file *filp, const char __user *buf, size_t len,
+               loff_t *ppos)
 {
-        struct file *file = iocb->ki_filp;
-        struct address_space * mapping = file->f_mapping;
-        size_t ocount;          /* original count */
-        size_t count;           /* after file limit checks */
-        struct inode    *inode = mapping->host;
-        unsigned long   seg;
-        loff_t          pos;
-        ssize_t         written;
-        ssize_t         err;
+        struct address_space *mapping = filp->f_mapping;
+        struct inode *inode = mapping->host;
+        size_t count;
+        loff_t pos;
+        ssize_t ret;
 
-        ocount = 0;
-        for (seg = 0; seg < nr_segs; seg++) {
-                const struct iovec *iv = &iov[seg];
+        down(&inode->i_sem);
 
-                /*
-                 * If any segment has a negative length, or the cumulative
-                 * length ever wraps negative then return -EINVAL.
-                 */
-                ocount += iv->iov_len;
-                if (unlikely((ssize_t)(ocount|iv->iov_len) < 0))
-                        return -EINVAL;
-                if (access_ok(VERIFY_READ, iv->iov_base, iv->iov_len))
-                        continue;
-                if (seg == 0)
-                        return -EFAULT;
-                nr_segs = seg;
-                ocount -= iv->iov_len;  /* This segment is no good */
-                break;
+        if (!access_ok(VERIFY_READ, buf, len)) {
+                ret=-EFAULT;
+                goto out_up;
         }
 
-        count = ocount;
         pos = *ppos;
+        count = len;
 
         vfs_check_frozen(inode->i_sb, SB_FREEZE_WRITE);
 
-        written = 0;
-
-        err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode));
-        if (err)
-                goto out;
+        /* We can write back this queue in page reclaim */
+        current->backing_dev_info = mapping->backing_dev_info;
 
+        ret = generic_write_checks(filp, &pos, &count, S_ISBLK(inode->i_mode));
+        if (ret)
+                goto out_backing;
         if (count == 0)
-                goto out;
+                goto out_backing;
 
-        err = remove_suid(file->f_dentry);
-        if (err)
-                goto out;
+        ret = remove_suid(filp->f_dentry);
+        if (ret)
+                goto out_backing;
 
         inode_update_time(inode, 1);
 
-        /* use execute in place to copy directly to disk */
-        written = do_xip_file_write (iocb, iov,
-                                  nr_segs, pos, ppos, count);
- out:
-        return written ? written : err;
-}
-
-static ssize_t
-__xip_file_write_nolock(struct file *file, const struct iovec *iov,
-                        unsigned long nr_segs, loff_t *ppos)
-{
-        struct kiocb kiocb;
-
-        init_sync_kiocb(&kiocb, file);
-        return xip_file_aio_write_nolock(&kiocb, iov, nr_segs, ppos);
-}
-
-ssize_t
-xip_file_aio_write(struct kiocb *iocb, const char __user *buf,
-                       size_t count, loff_t pos)
-{
-        struct file *file = iocb->ki_filp;
-        struct address_space *mapping = file->f_mapping;
-        struct inode *inode = mapping->host;
-        ssize_t ret;
-        struct iovec local_iov = { .iov_base = (void __user *)buf,
-                                   .iov_len = count };
+        ret = __xip_file_write (filp, buf, count, pos, ppos);
 
-        BUG_ON(iocb->ki_pos != pos);
-
-        down(&inode->i_sem);
-        ret = xip_file_aio_write_nolock(iocb, &local_iov, 1, &iocb->ki_pos);
+ out_backing:
+        current->backing_dev_info = NULL;
+ out_up:
         up(&inode->i_sem);
         return ret;
 }
-EXPORT_SYMBOL_GPL(xip_file_aio_write);
-
-ssize_t xip_file_writev(struct file *file, const struct iovec *iov,
-                        unsigned long nr_segs, loff_t *ppos)
-{
-        struct address_space *mapping = file->f_mapping;
-        struct inode *inode = mapping->host;
-        ssize_t ret;
-
-        down(&inode->i_sem);
-        ret = __xip_file_write_nolock(file, iov, nr_segs, ppos);
-        up(&inode->i_sem);
-        return ret;
-}
-EXPORT_SYMBOL_GPL(xip_file_writev);
+EXPORT_SYMBOL_GPL(xip_file_write);
 
 /*
  * truncate a page used for execute in place
@@ -541,7 +413,6 @@ xip_truncate_page(struct address_space *mapping, loff_t from)
         unsigned length;
         struct page *page;
         void *kaddr;
-        int err;
 
         BUG_ON(!mapping->a_ops->get_xip_page);
 
@@ -556,17 +427,14 @@ xip_truncate_page(struct address_space *mapping, loff_t from)
 
         page = mapping->a_ops->get_xip_page(mapping,
                                             index*(PAGE_SIZE/512), 0);
-        err = -ENOMEM;
         if (!page)
-                goto out;
+                return -ENOMEM;
         if (unlikely(IS_ERR(page))) {
-                if (PTR_ERR(page) == -ENODATA) {
+                if (PTR_ERR(page) == -ENODATA)
                         /* Hole? No need to truncate */
                         return 0;
-                } else {
-                        err = PTR_ERR(page);
-                        goto out;
-                }
+                else
+                        return PTR_ERR(page);
         } else
                 BUG_ON(!PageUptodate(page));
         kaddr = kmap_atomic(page, KM_USER0);
@@ -574,8 +442,6 @@ xip_truncate_page(struct address_space *mapping, loff_t from)
         kunmap_atomic(kaddr, KM_USER0);
 
         flush_dcache_page(page);
-        err = 0;
-out:
-        return err;
+        return 0;
 }
 EXPORT_SYMBOL_GPL(xip_truncate_page);