X-Git-Url: https://git.openpandora.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=mm%2Ffilemap.c;h=849293c4f4187fd9da77554edd98e11785d9298d;hb=148f948ba877f4d3cdef036b1ff6d9f68986706a;hp=ccea3b665c12571ac32d6d936b3862e103f7b995;hpb=a9d90c81b536cc0567bdf22a8aaefe180a5b0f7a;p=pandora-kernel.git diff --git a/mm/filemap.c b/mm/filemap.c index ccea3b665c12..849293c4f418 100644 --- a/mm/filemap.c +++ b/mm/filemap.c @@ -39,11 +39,10 @@ /* * FIXME: remove all knowledge of the buffer layer from the core VM */ -#include /* for generic_osync_inode */ +#include /* for try_to_free_buffers */ #include - /* * Shared mappings implemented 30.11.1994. It's not fully working yet, * though. @@ -306,6 +305,26 @@ int wait_on_page_writeback_range(struct address_space *mapping, return ret; } +/** + * filemap_fdatawait_range - wait for all under-writeback pages to complete in a given range + * @mapping: address space structure to wait for + * @start: offset in bytes where the range starts + * @end: offset in bytes where the range ends (inclusive) + * + * Walk the list of under-writeback pages of the given address space + * in the given range and wait for all of them. + * + * This is just a simple wrapper so that callers don't have to convert offsets + * to page indexes themselves + */ +int filemap_fdatawait_range(struct address_space *mapping, loff_t start, + loff_t end) +{ + return wait_on_page_writeback_range(mapping, start >> PAGE_CACHE_SHIFT, + end >> PAGE_CACHE_SHIFT); +} +EXPORT_SYMBOL(filemap_fdatawait_range); + /** * sync_page_range - write and wait on all pages in the passed range * @inode: target inode @@ -2167,20 +2186,7 @@ generic_file_direct_write(struct kiocb *iocb, const struct iovec *iov, } *ppos = end; } - - /* - * Sync the fs metadata but not the minor inode changes and - * of course not the data as we did direct DMA for the IO. - * i_mutex is held, which protects generic_osync_inode() from - * livelocking. AIO O_DIRECT ops attempt to sync metadata here. - */ out: - if ((written >= 0 || written == -EIOCBQUEUED) && - ((file->f_flags & O_SYNC) || IS_SYNC(inode))) { - int err = generic_osync_inode(inode, mapping, OSYNC_METADATA); - if (err < 0) - written = err; - } return written; } EXPORT_SYMBOL(generic_file_direct_write); @@ -2312,8 +2318,6 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov, { struct file *file = iocb->ki_filp; struct address_space *mapping = file->f_mapping; - const struct address_space_operations *a_ops = mapping->a_ops; - struct inode *inode = mapping->host; ssize_t status; struct iov_iter i; @@ -2323,16 +2327,6 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov, if (likely(status >= 0)) { written += status; *ppos = pos + status; - - /* - * For now, when the user asks for O_SYNC, we'll actually give - * O_DSYNC - */ - if (unlikely((file->f_flags & O_SYNC) || IS_SYNC(inode))) { - if (!a_ops->writepage || !is_sync_kiocb(iocb)) - status = generic_osync_inode(inode, mapping, - OSYNC_METADATA|OSYNC_DATA); - } } /* @@ -2348,9 +2342,27 @@ generic_file_buffered_write(struct kiocb *iocb, const struct iovec *iov, } EXPORT_SYMBOL(generic_file_buffered_write); -static ssize_t -__generic_file_aio_write_nolock(struct kiocb *iocb, const struct iovec *iov, - unsigned long nr_segs, loff_t *ppos) +/** + * __generic_file_aio_write - write data to a file + * @iocb: IO state structure (file, offset, etc.) + * @iov: vector with data to write + * @nr_segs: number of segments in the vector + * @ppos: position where to write + * + * This function does all the work needed for actually writing data to a + * file. It does all basic checks, removes SUID from the file, updates + * modification times and calls proper subroutines depending on whether we + * do direct IO or a standard buffered write. + * + * It expects i_mutex to be grabbed unless we work on a block device or similar + * object which does not need locking at all. + * + * This function does *not* take care of syncing data in case of O_SYNC write. + * A caller has to handle it. This is mainly due to the fact that we want to + * avoid syncing under i_mutex. + */ +ssize_t __generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov, + unsigned long nr_segs, loff_t *ppos) { struct file *file = iocb->ki_filp; struct address_space * mapping = file->f_mapping; @@ -2447,51 +2459,37 @@ out: current->backing_dev_info = NULL; return written ? written : err; } +EXPORT_SYMBOL(__generic_file_aio_write); -ssize_t generic_file_aio_write_nolock(struct kiocb *iocb, - const struct iovec *iov, unsigned long nr_segs, loff_t pos) -{ - struct file *file = iocb->ki_filp; - struct address_space *mapping = file->f_mapping; - struct inode *inode = mapping->host; - ssize_t ret; - - BUG_ON(iocb->ki_pos != pos); - - ret = __generic_file_aio_write_nolock(iocb, iov, nr_segs, - &iocb->ki_pos); - - if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) { - ssize_t err; - - err = sync_page_range_nolock(inode, mapping, pos, ret); - if (err < 0) - ret = err; - } - return ret; -} -EXPORT_SYMBOL(generic_file_aio_write_nolock); - +/** + * generic_file_aio_write - write data to a file + * @iocb: IO state structure + * @iov: vector with data to write + * @nr_segs: number of segments in the vector + * @pos: position in file where to write + * + * This is a wrapper around __generic_file_aio_write() to be used by most + * filesystems. It takes care of syncing the file in case of O_SYNC file + * and acquires i_mutex as needed. + */ ssize_t generic_file_aio_write(struct kiocb *iocb, const struct iovec *iov, unsigned long nr_segs, loff_t pos) { struct file *file = iocb->ki_filp; - struct address_space *mapping = file->f_mapping; - struct inode *inode = mapping->host; + struct inode *inode = file->f_mapping->host; ssize_t ret; BUG_ON(iocb->ki_pos != pos); mutex_lock(&inode->i_mutex); - ret = __generic_file_aio_write_nolock(iocb, iov, nr_segs, - &iocb->ki_pos); + ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos); mutex_unlock(&inode->i_mutex); - if (ret > 0 && ((file->f_flags & O_SYNC) || IS_SYNC(inode))) { + if (ret > 0 || ret == -EIOCBQUEUED) { ssize_t err; - err = sync_page_range(inode, mapping, pos, ret); - if (err < 0) + err = generic_write_sync(file, pos, ret); + if (err < 0 && ret > 0) ret = err; } return ret;