From 5eec54fcde7e065eb3d8a6e70e61d90673ca706b Mon Sep 17 00:00:00 2001 From: Ian Abbott Date: Wed, 5 Sep 2012 17:44:31 +0100 Subject: UDF: Add support for O_DIRECT Add support for the O_DIRECT flag. There are two cases to deal with: 1. Small files stored in the ICB (inode control block?): just return 0 from the new udf_adinicb_direct_IO() handler to fall back to buffered I/O. 2. Larger files, not stored in the ICB: nothing special here. Just call blockdev_direct_IO() from our new udf_direct_IO() handler and tidy up any blocks instantiated outside i_size on error. This is pretty standard. Factor error handling code out of udf_write_begin() into new function udf_write_failed() so it can also be called by udf_direct_IO(). Also change the whitespace in udf_aops to make it a bit neater. Signed-off-by: Ian Abbott Signed-off-by: Jan Kara --- arch/um/os-Linux/time.c | 2 +- fs/udf/file.c | 9 +++++++++ fs/udf/inode.c | 52 ++++++++++++++++++++++++++++++++++--------------- 3 files changed, 46 insertions(+), 17 deletions(-) diff --git a/arch/um/os-Linux/time.c b/arch/um/os-Linux/time.c index f60238559af3..0748fe0c8a73 100644 --- a/arch/um/os-Linux/time.c +++ b/arch/um/os-Linux/time.c @@ -114,7 +114,7 @@ static void deliver_alarm(void) skew += this_tick - last_tick; while (skew >= one_tick) { - alarm_handler(SIGVTALRM, NULL); + alarm_handler(SIGVTALRM, NULL, NULL); skew -= one_tick; } diff --git a/fs/udf/file.c b/fs/udf/file.c index d1c6093fd3d3..77b5953eaac8 100644 --- a/fs/udf/file.c +++ b/fs/udf/file.c @@ -118,11 +118,20 @@ static int udf_adinicb_write_end(struct file *file, return simple_write_end(file, mapping, pos, len, copied, page, fsdata); } +static ssize_t udf_adinicb_direct_IO(int rw, struct kiocb *iocb, + const struct iovec *iov, + loff_t offset, unsigned long nr_segs) +{ + /* Fallback to buffered I/O. */ + return 0; +} + const struct address_space_operations udf_adinicb_aops = { .readpage = udf_adinicb_readpage, .writepage = udf_adinicb_writepage, .write_begin = udf_adinicb_write_begin, .write_end = udf_adinicb_write_end, + .direct_IO = udf_adinicb_direct_IO, }; static ssize_t udf_file_aio_write(struct kiocb *iocb, const struct iovec *iov, diff --git a/fs/udf/inode.c b/fs/udf/inode.c index 1a0588e77a2f..41d58309d6a8 100644 --- a/fs/udf/inode.c +++ b/fs/udf/inode.c @@ -95,6 +95,22 @@ void udf_evict_inode(struct inode *inode) } } +static void udf_write_failed(struct address_space *mapping, loff_t to) +{ + struct inode *inode = mapping->host; + struct udf_inode_info *iinfo = UDF_I(inode); + loff_t isize = inode->i_size; + + if (to > isize) { + truncate_pagecache(inode, to, isize); + if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) { + down_write(&iinfo->i_data_sem); + udf_truncate_extents(inode); + up_write(&iinfo->i_data_sem); + } + } +} + static int udf_writepage(struct page *page, struct writeback_control *wbc) { return block_write_full_page(page, udf_get_block, wbc); @@ -124,21 +140,24 @@ static int udf_write_begin(struct file *file, struct address_space *mapping, int ret; ret = block_write_begin(mapping, pos, len, flags, pagep, udf_get_block); - if (unlikely(ret)) { - struct inode *inode = mapping->host; - struct udf_inode_info *iinfo = UDF_I(inode); - loff_t isize = inode->i_size; - - if (pos + len > isize) { - truncate_pagecache(inode, pos + len, isize); - if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) { - down_write(&iinfo->i_data_sem); - udf_truncate_extents(inode); - up_write(&iinfo->i_data_sem); - } - } - } + if (unlikely(ret)) + udf_write_failed(mapping, pos + len); + return ret; +} +static ssize_t udf_direct_IO(int rw, struct kiocb *iocb, + const struct iovec *iov, + loff_t offset, unsigned long nr_segs) +{ + struct file *file = iocb->ki_filp; + struct address_space *mapping = file->f_mapping; + struct inode *inode = mapping->host; + ssize_t ret; + + ret = blockdev_direct_IO(rw, iocb, inode, iov, offset, nr_segs, + udf_get_block); + if (unlikely(ret < 0 && (rw & WRITE))) + udf_write_failed(mapping, offset + iov_length(iov, nr_segs)); return ret; } @@ -152,8 +171,9 @@ const struct address_space_operations udf_aops = { .readpages = udf_readpages, .writepage = udf_writepage, .writepages = udf_writepages, - .write_begin = udf_write_begin, - .write_end = generic_write_end, + .write_begin = udf_write_begin, + .write_end = generic_write_end, + .direct_IO = udf_direct_IO, .bmap = udf_bmap, }; -- cgit v1.2.3