Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
[sfrench/cifs-2.6.git] / fs / ocfs2 / aops.c
index 34d10452c56d305f13edeb8cab0228bac50304f4..bc7b4cbbe8eca6f418761b64d0ff8f24141242b0 100644 (file)
@@ -26,6 +26,7 @@
 #include <asm/byteorder.h>
 #include <linux/swap.h>
 #include <linux/pipe_fs_i.h>
+#include <linux/mpage.h>
 
 #define MLOG_MASK_PREFIX ML_FILE_IO
 #include <cluster/masklog.h>
@@ -139,7 +140,8 @@ static int ocfs2_get_block(struct inode *inode, sector_t iblock,
 {
        int err = 0;
        unsigned int ext_flags;
-       u64 p_blkno, past_eof;
+       u64 max_blocks = bh_result->b_size >> inode->i_blkbits;
+       u64 p_blkno, count, past_eof;
        struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
 
        mlog_entry("(0x%p, %llu, 0x%p, %d)\n", inode,
@@ -155,7 +157,7 @@ static int ocfs2_get_block(struct inode *inode, sector_t iblock,
                goto bail;
        }
 
-       err = ocfs2_extent_map_get_blocks(inode, iblock, &p_blkno, NULL,
+       err = ocfs2_extent_map_get_blocks(inode, iblock, &p_blkno, &count,
                                          &ext_flags);
        if (err) {
                mlog(ML_ERROR, "Error %d from get_blocks(0x%p, %llu, 1, "
@@ -164,6 +166,9 @@ static int ocfs2_get_block(struct inode *inode, sector_t iblock,
                goto bail;
        }
 
+       if (max_blocks < count)
+               count = max_blocks;
+
        /*
         * ocfs2 never allocates in this function - the only time we
         * need to use BH_New is when we're extending i_size on a file
@@ -178,6 +183,8 @@ static int ocfs2_get_block(struct inode *inode, sector_t iblock,
        if (p_blkno && !(ext_flags & OCFS2_EXT_UNWRITTEN))
                map_bh(bh_result, inode->i_sb, p_blkno);
 
+       bh_result->b_size = count << inode->i_blkbits;
+
        if (!ocfs2_sparse_alloc(osb)) {
                if (p_blkno == 0) {
                        err = -EIO;
@@ -210,7 +217,7 @@ int ocfs2_read_inline_data(struct inode *inode, struct page *page,
                           struct buffer_head *di_bh)
 {
        void *kaddr;
-       unsigned int size;
+       loff_t size;
        struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
 
        if (!(le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_DATA_FL)) {
@@ -224,8 +231,9 @@ int ocfs2_read_inline_data(struct inode *inode, struct page *page,
        if (size > PAGE_CACHE_SIZE ||
            size > ocfs2_max_inline_data(inode->i_sb)) {
                ocfs2_error(inode->i_sb,
-                           "Inode %llu has with inline data has bad size: %u",
-                           (unsigned long long)OCFS2_I(inode)->ip_blkno, size);
+                           "Inode %llu has with inline data has bad size: %Lu",
+                           (unsigned long long)OCFS2_I(inode)->ip_blkno,
+                           (unsigned long long)size);
                return -EROFS;
        }
 
@@ -275,7 +283,7 @@ static int ocfs2_readpage(struct file *file, struct page *page)
 
        mlog_entry("(0x%p, %lu)\n", file, (page ? page->index : 0));
 
-       ret = ocfs2_meta_lock_with_page(inode, NULL, 0, page);
+       ret = ocfs2_inode_lock_with_page(inode, NULL, 0, page);
        if (ret != 0) {
                if (ret == AOP_TRUNCATED_PAGE)
                        unlock = 0;
@@ -285,7 +293,7 @@ static int ocfs2_readpage(struct file *file, struct page *page)
 
        if (down_read_trylock(&oi->ip_alloc_sem) == 0) {
                ret = AOP_TRUNCATED_PAGE;
-               goto out_meta_unlock;
+               goto out_inode_unlock;
        }
 
        /*
@@ -305,25 +313,16 @@ static int ocfs2_readpage(struct file *file, struct page *page)
                goto out_alloc;
        }
 
-       ret = ocfs2_data_lock_with_page(inode, 0, page);
-       if (ret != 0) {
-               if (ret == AOP_TRUNCATED_PAGE)
-                       unlock = 0;
-               mlog_errno(ret);
-               goto out_alloc;
-       }
-
        if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL)
                ret = ocfs2_readpage_inline(inode, page);
        else
                ret = block_read_full_page(page, ocfs2_get_block);
        unlock = 0;
 
-       ocfs2_data_unlock(inode, 0);
 out_alloc:
        up_read(&OCFS2_I(inode)->ip_alloc_sem);
-out_meta_unlock:
-       ocfs2_meta_unlock(inode, 0);
+out_inode_unlock:
+       ocfs2_inode_unlock(inode, 0);
 out:
        if (unlock)
                unlock_page(page);
@@ -331,6 +330,62 @@ out:
        return ret;
 }
 
+/*
+ * This is used only for read-ahead. Failures or difficult to handle
+ * situations are safe to ignore.
+ *
+ * Right now, we don't bother with BH_Boundary - in-inode extent lists
+ * are quite large (243 extents on 4k blocks), so most inodes don't
+ * grow out to a tree. If need be, detecting boundary extents could
+ * trivially be added in a future version of ocfs2_get_block().
+ */
+static int ocfs2_readpages(struct file *filp, struct address_space *mapping,
+                          struct list_head *pages, unsigned nr_pages)
+{
+       int ret, err = -EIO;
+       struct inode *inode = mapping->host;
+       struct ocfs2_inode_info *oi = OCFS2_I(inode);
+       loff_t start;
+       struct page *last;
+
+       /*
+        * Use the nonblocking flag for the dlm code to avoid page
+        * lock inversion, but don't bother with retrying.
+        */
+       ret = ocfs2_inode_lock_full(inode, NULL, 0, OCFS2_LOCK_NONBLOCK);
+       if (ret)
+               return err;
+
+       if (down_read_trylock(&oi->ip_alloc_sem) == 0) {
+               ocfs2_inode_unlock(inode, 0);
+               return err;
+       }
+
+       /*
+        * Don't bother with inline-data. There isn't anything
+        * to read-ahead in that case anyway...
+        */
+       if (oi->ip_dyn_features & OCFS2_INLINE_DATA_FL)
+               goto out_unlock;
+
+       /*
+        * Check whether a remote node truncated this file - we just
+        * drop out in that case as it's not worth handling here.
+        */
+       last = list_entry(pages->prev, struct page, lru);
+       start = (loff_t)last->index << PAGE_CACHE_SHIFT;
+       if (start >= i_size_read(inode))
+               goto out_unlock;
+
+       err = mpage_readpages(mapping, pages, nr_pages, ocfs2_get_block);
+
+out_unlock:
+       up_read(&oi->ip_alloc_sem);
+       ocfs2_inode_unlock(inode, 0);
+
+       return err;
+}
+
 /* Note: Because we don't support holes, our allocation has
  * already happened (allocation writes zeros to the file data)
  * so we don't have to worry about ordered writes in
@@ -452,7 +507,7 @@ static sector_t ocfs2_bmap(struct address_space *mapping, sector_t block)
         * accessed concurrently from multiple nodes.
         */
        if (!INODE_JOURNAL(inode)) {
-               err = ocfs2_meta_lock(inode, NULL, 0);
+               err = ocfs2_inode_lock(inode, NULL, 0);
                if (err) {
                        if (err != -ENOENT)
                                mlog_errno(err);
@@ -467,7 +522,7 @@ static sector_t ocfs2_bmap(struct address_space *mapping, sector_t block)
 
        if (!INODE_JOURNAL(inode)) {
                up_read(&OCFS2_I(inode)->ip_alloc_sem);
-               ocfs2_meta_unlock(inode, 0);
+               ocfs2_inode_unlock(inode, 0);
        }
 
        if (err) {
@@ -638,34 +693,12 @@ static ssize_t ocfs2_direct_IO(int rw,
        if (OCFS2_I(inode)->ip_dyn_features & OCFS2_INLINE_DATA_FL)
                return 0;
 
-       if (!ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb))) {
-               /*
-                * We get PR data locks even for O_DIRECT.  This
-                * allows concurrent O_DIRECT I/O but doesn't let
-                * O_DIRECT with extending and buffered zeroing writes
-                * race.  If they did race then the buffered zeroing
-                * could be written back after the O_DIRECT I/O.  It's
-                * one thing to tell people not to mix buffered and
-                * O_DIRECT writes, but expecting them to understand
-                * that file extension is also an implicit buffered
-                * write is too much.  By getting the PR we force
-                * writeback of the buffered zeroing before
-                * proceeding.
-                */
-               ret = ocfs2_data_lock(inode, 0);
-               if (ret < 0) {
-                       mlog_errno(ret);
-                       goto out;
-               }
-               ocfs2_data_unlock(inode, 0);
-       }
-
        ret = blockdev_direct_IO_no_locking(rw, iocb, inode,
                                            inode->i_sb->s_bdev, iov, offset,
                                            nr_segs, 
                                            ocfs2_direct_IO_get_blocks,
                                            ocfs2_dio_end_io);
-out:
+
        mlog_exit(ret);
        return ret;
 }
@@ -728,6 +761,27 @@ static void ocfs2_clear_page_regions(struct page *page,
        kunmap_atomic(kaddr, KM_USER0);
 }
 
+/*
+ * Nonsparse file systems fully allocate before we get to the write
+ * code. This prevents ocfs2_write() from tagging the write as an
+ * allocating one, which means ocfs2_map_page_blocks() might try to
+ * read-in the blocks at the tail of our file. Avoid reading them by
+ * testing i_size against each block offset.
+ */
+static int ocfs2_should_read_blk(struct inode *inode, struct page *page,
+                                unsigned int block_start)
+{
+       u64 offset = page_offset(page) + block_start;
+
+       if (ocfs2_sparse_alloc(OCFS2_SB(inode->i_sb)))
+               return 1;
+
+       if (i_size_read(inode) > offset)
+               return 1;
+
+       return 0;
+}
+
 /*
  * Some of this taken from block_prepare_write(). We already have our
  * mapping by now though, and the entire write will be allocating or
@@ -781,6 +835,7 @@ int ocfs2_map_page_blocks(struct page *page, u64 *p_blkno,
                                set_buffer_uptodate(bh);
                } else if (!buffer_uptodate(bh) && !buffer_delay(bh) &&
                           !buffer_new(bh) &&
+                          ocfs2_should_read_blk(inode, page, block_start) &&
                           (block_start < from || block_end > to)) {
                        ll_rw_block(READ, 1, &bh);
                        *wait_bh++=bh;
@@ -1492,7 +1547,7 @@ int ocfs2_size_fits_inline_data(struct buffer_head *di_bh, u64 new_size)
 {
        struct ocfs2_dinode *di = (struct ocfs2_dinode *)di_bh->b_data;
 
-       if (new_size < le16_to_cpu(di->id2.i_data.id_count))
+       if (new_size <= le16_to_cpu(di->id2.i_data.id_count))
                return 1;
        return 0;
 }
@@ -1724,15 +1779,15 @@ out:
        return ret;
 }
 
-int ocfs2_write_begin(struct file *file, struct address_space *mapping,
-                     loff_t pos, unsigned len, unsigned flags,
-                     struct page **pagep, void **fsdata)
+static int ocfs2_write_begin(struct file *file, struct address_space *mapping,
+                            loff_t pos, unsigned len, unsigned flags,
+                            struct page **pagep, void **fsdata)
 {
        int ret;
        struct buffer_head *di_bh = NULL;
        struct inode *inode = mapping->host;
 
-       ret = ocfs2_meta_lock(inode, &di_bh, 1);
+       ret = ocfs2_inode_lock(inode, &di_bh, 1);
        if (ret) {
                mlog_errno(ret);
                return ret;
@@ -1747,30 +1802,22 @@ int ocfs2_write_begin(struct file *file, struct address_space *mapping,
         */
        down_write(&OCFS2_I(inode)->ip_alloc_sem);
 
-       ret = ocfs2_data_lock(inode, 1);
-       if (ret) {
-               mlog_errno(ret);
-               goto out_fail;
-       }
-
        ret = ocfs2_write_begin_nolock(mapping, pos, len, flags, pagep,
                                       fsdata, di_bh, NULL);
        if (ret) {
                mlog_errno(ret);
-               goto out_fail_data;
+               goto out_fail;
        }
 
        brelse(di_bh);
 
        return 0;
 
-out_fail_data:
-       ocfs2_data_unlock(inode, 1);
 out_fail:
        up_write(&OCFS2_I(inode)->ip_alloc_sem);
 
        brelse(di_bh);
-       ocfs2_meta_unlock(inode, 1);
+       ocfs2_inode_unlock(inode, 1);
 
        return ret;
 }
@@ -1877,25 +1924,27 @@ out_write_size:
        return copied;
 }
 
-int ocfs2_write_end(struct file *file, struct address_space *mapping,
-                   loff_t pos, unsigned len, unsigned copied,
-                   struct page *page, void *fsdata)
+static int ocfs2_write_end(struct file *file, struct address_space *mapping,
+                          loff_t pos, unsigned len, unsigned copied,
+                          struct page *page, void *fsdata)
 {
        int ret;
        struct inode *inode = mapping->host;
 
        ret = ocfs2_write_end_nolock(mapping, pos, len, copied, page, fsdata);
 
-       ocfs2_data_unlock(inode, 1);
        up_write(&OCFS2_I(inode)->ip_alloc_sem);
-       ocfs2_meta_unlock(inode, 1);
+       ocfs2_inode_unlock(inode, 1);
 
        return ret;
 }
 
 const struct address_space_operations ocfs2_aops = {
        .readpage       = ocfs2_readpage,
+       .readpages      = ocfs2_readpages,
        .writepage      = ocfs2_writepage,
+       .write_begin    = ocfs2_write_begin,
+       .write_end      = ocfs2_write_end,
        .bmap           = ocfs2_bmap,
        .sync_page      = block_sync_page,
        .direct_IO      = ocfs2_direct_IO,