diff options
| -rw-r--r-- | fs/ocfs2/aops.c | 68 |
1 files changed, 66 insertions, 2 deletions
diff --git a/fs/ocfs2/aops.c b/fs/ocfs2/aops.c index ac8c390..286af3a 100644 --- a/fs/ocfs2/aops.c +++ b/fs/ocfs2/aops.c @@ -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; @@ -322,6 +329,62 @@ 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 @@ -1877,6 +1940,7 @@ static int ocfs2_write_end(struct file *file, struct address_space *mapping, 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, |