diff options
Diffstat (limited to 'fs/xfs/linux-2.6/xfs_file.c')
| -rw-r--r-- | fs/xfs/linux-2.6/xfs_file.c | 1114 |
1 files changed, 0 insertions, 1114 deletions
diff --git a/fs/xfs/linux-2.6/xfs_file.c b/fs/xfs/linux-2.6/xfs_file.c deleted file mode 100644 index b679198..0000000 --- a/fs/xfs/linux-2.6/xfs_file.c +++ /dev/null @@ -1,1114 +0,0 @@ -/* - * Copyright (c) 2000-2005 Silicon Graphics, Inc. - * All Rights Reserved. - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License as - * published by the Free Software Foundation. - * - * This program is distributed in the hope that it would be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write the Free Software Foundation, - * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA - */ -#include "xfs.h" -#include "xfs_fs.h" -#include "xfs_bit.h" -#include "xfs_log.h" -#include "xfs_inum.h" -#include "xfs_sb.h" -#include "xfs_ag.h" -#include "xfs_trans.h" -#include "xfs_mount.h" -#include "xfs_bmap_btree.h" -#include "xfs_alloc.h" -#include "xfs_dinode.h" -#include "xfs_inode.h" -#include "xfs_inode_item.h" -#include "xfs_bmap.h" -#include "xfs_error.h" -#include "xfs_vnodeops.h" -#include "xfs_da_btree.h" -#include "xfs_ioctl.h" -#include "xfs_trace.h" - -#include <linux/dcache.h> -#include <linux/falloc.h> - -static const struct vm_operations_struct xfs_file_vm_ops; - -/* - * Locking primitives for read and write IO paths to ensure we consistently use - * and order the inode->i_mutex, ip->i_lock and ip->i_iolock. - */ -static inline void -xfs_rw_ilock( - struct xfs_inode *ip, - int type) -{ - if (type & XFS_IOLOCK_EXCL) - mutex_lock(&VFS_I(ip)->i_mutex); - xfs_ilock(ip, type); -} - -static inline void -xfs_rw_iunlock( - struct xfs_inode *ip, - int type) -{ - xfs_iunlock(ip, type); - if (type & XFS_IOLOCK_EXCL) - mutex_unlock(&VFS_I(ip)->i_mutex); -} - -static inline void -xfs_rw_ilock_demote( - struct xfs_inode *ip, - int type) -{ - xfs_ilock_demote(ip, type); - if (type & XFS_IOLOCK_EXCL) - mutex_unlock(&VFS_I(ip)->i_mutex); -} - -/* - * xfs_iozero - * - * xfs_iozero clears the specified range of buffer supplied, - * and marks all the affected blocks as valid and modified. If - * an affected block is not allocated, it will be allocated. If - * an affected block is not completely overwritten, and is not - * valid before the operation, it will be read from disk before - * being partially zeroed. - */ -STATIC int -xfs_iozero( - struct xfs_inode *ip, /* inode */ - loff_t pos, /* offset in file */ - size_t count) /* size of data to zero */ -{ - struct page *page; - struct address_space *mapping; - int status; - - mapping = VFS_I(ip)->i_mapping; - do { - unsigned offset, bytes; - void *fsdata; - - offset = (pos & (PAGE_CACHE_SIZE -1)); /* Within page */ - bytes = PAGE_CACHE_SIZE - offset; - if (bytes > count) - bytes = count; - - status = pagecache_write_begin(NULL, mapping, pos, bytes, - AOP_FLAG_UNINTERRUPTIBLE, - &page, &fsdata); - if (status) - break; - - zero_user(page, offset, bytes); - - status = pagecache_write_end(NULL, mapping, pos, bytes, bytes, - page, fsdata); - WARN_ON(status <= 0); /* can't return less than zero! */ - pos += bytes; - count -= bytes; - status = 0; - } while (count); - - return (-status); -} - -STATIC int -xfs_file_fsync( - struct file *file, - int datasync) -{ - struct inode *inode = file->f_mapping->host; - struct xfs_inode *ip = XFS_I(inode); - struct xfs_mount *mp = ip->i_mount; - struct xfs_trans *tp; - int error = 0; - int log_flushed = 0; - - trace_xfs_file_fsync(ip); - - if (XFS_FORCED_SHUTDOWN(mp)) - return -XFS_ERROR(EIO); - - xfs_iflags_clear(ip, XFS_ITRUNCATED); - - xfs_ioend_wait(ip); - - if (mp->m_flags & XFS_MOUNT_BARRIER) { - /* - * If we have an RT and/or log subvolume we need to make sure - * to flush the write cache the device used for file data - * first. This is to ensure newly written file data make - * it to disk before logging the new inode size in case of - * an extending write. - */ - if (XFS_IS_REALTIME_INODE(ip)) - xfs_blkdev_issue_flush(mp->m_rtdev_targp); - else if (mp->m_logdev_targp != mp->m_ddev_targp) - xfs_blkdev_issue_flush(mp->m_ddev_targp); - } - - /* - * We always need to make sure that the required inode state is safe on - * disk. The inode might be clean but we still might need to force the - * log because of committed transactions that haven't hit the disk yet. - * Likewise, there could be unflushed non-transactional changes to the - * inode core that have to go to disk and this requires us to issue - * a synchronous transaction to capture these changes correctly. - * - * This code relies on the assumption that if the i_update_core field - * of the inode is clear and the inode is unpinned then it is clean - * and no action is required. - */ - xfs_ilock(ip, XFS_ILOCK_SHARED); - - /* - * First check if the VFS inode is marked dirty. All the dirtying - * of non-transactional updates no goes through mark_inode_dirty*, - * which allows us to distinguish beteeen pure timestamp updates - * and i_size updates which need to be caught for fdatasync. - * After that also theck for the dirty state in the XFS inode, which - * might gets cleared when the inode gets written out via the AIL - * or xfs_iflush_cluster. - */ - if (((inode->i_state & I_DIRTY_DATASYNC) || - ((inode->i_state & I_DIRTY_SYNC) && !datasync)) && - ip->i_update_core) { - /* - * Kick off a transaction to log the inode core to get the - * updates. The sync transaction will also force the log. - */ - xfs_iunlock(ip, XFS_ILOCK_SHARED); - tp = xfs_trans_alloc(mp, XFS_TRANS_FSYNC_TS); - error = xfs_trans_reserve(tp, 0, - XFS_FSYNC_TS_LOG_RES(mp), 0, 0, 0); - if (error) { - xfs_trans_cancel(tp, 0); - return -error; - } - xfs_ilock(ip, XFS_ILOCK_EXCL); - - /* - * Note - it's possible that we might have pushed ourselves out - * of the way during trans_reserve which would flush the inode. - * But there's no guarantee that the inode buffer has actually - * gone out yet (it's delwri). Plus the buffer could be pinned - * anyway if it's part of an inode in another recent - * transaction. So we play it safe and fire off the - * transaction anyway. - */ - xfs_trans_ijoin(tp, ip); - xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE); - xfs_trans_set_sync(tp); - error = _xfs_trans_commit(tp, 0, &log_flushed); - - xfs_iunlock(ip, XFS_ILOCK_EXCL); - } else { - /* - * Timestamps/size haven't changed since last inode flush or - * inode transaction commit. That means either nothing got - * written or a transaction committed which caught the updates. - * If the latter happened and the transaction hasn't hit the - * disk yet, the inode will be still be pinned. If it is, - * force the log. - */ - if (xfs_ipincount(ip)) { - error = _xfs_log_force_lsn(mp, - ip->i_itemp->ili_last_lsn, - XFS_LOG_SYNC, &log_flushed); - } - xfs_iunlock(ip, XFS_ILOCK_SHARED); - } - - /* - * If we only have a single device, and the log force about was - * a no-op we might have to flush the data device cache here. - * This can only happen for fdatasync/O_DSYNC if we were overwriting - * an already allocated file and thus do not have any metadata to - * commit. - */ - if ((mp->m_flags & XFS_MOUNT_BARRIER) && - mp->m_logdev_targp == mp->m_ddev_targp && - !XFS_IS_REALTIME_INODE(ip) && - !log_flushed) - xfs_blkdev_issue_flush(mp->m_ddev_targp); - - return -error; -} - -STATIC ssize_t -xfs_file_aio_read( - struct kiocb *iocb, - const struct iovec *iovp, - unsigned long nr_segs, - loff_t pos) -{ - struct file *file = iocb->ki_filp; - struct inode *inode = file->f_mapping->host; - struct xfs_inode *ip = XFS_I(inode); - struct xfs_mount *mp = ip->i_mount; - size_t size = 0; - ssize_t ret = 0; - int ioflags = 0; - xfs_fsize_t n; - unsigned long seg; - - XFS_STATS_INC(xs_read_calls); - - BUG_ON(iocb->ki_pos != pos); - - if (unlikely(file->f_flags & O_DIRECT)) - ioflags |= IO_ISDIRECT; - if (file->f_mode & FMODE_NOCMTIME) - ioflags |= IO_INVIS; - - /* START copy & waste from filemap.c */ - for (seg = 0; seg < nr_segs; seg++) { - const struct iovec *iv = &iovp[seg]; - - /* - * If any segment has a negative length, or the cumulative - * length ever wraps negative then return -EINVAL. - */ - size += iv->iov_len; - if (unlikely((ssize_t)(size|iv->iov_len) < 0)) - return XFS_ERROR(-EINVAL); - } - /* END copy & waste from filemap.c */ - - if (unlikely(ioflags & IO_ISDIRECT)) { - xfs_buftarg_t *target = - XFS_IS_REALTIME_INODE(ip) ? - mp->m_rtdev_targp : mp->m_ddev_targp; - if ((iocb->ki_pos & target->bt_smask) || - (size & target->bt_smask)) { - if (iocb->ki_pos == ip->i_size) - return 0; - return -XFS_ERROR(EINVAL); - } - } - - n = XFS_MAXIOFFSET(mp) - iocb->ki_pos; - if (n <= 0 || size == 0) - return 0; - - if (n < size) - size = n; - - if (XFS_FORCED_SHUTDOWN(mp)) - return -EIO; - - /* - * Locking is a bit tricky here. If we take an exclusive lock - * for direct IO, we effectively serialise all new concurrent - * read IO to this file and block it behind IO that is currently in - * progress because IO in progress holds the IO lock shared. We only - * need to hold the lock exclusive to blow away the page cache, so - * only take lock exclusively if the page cache needs invalidation. - * This allows the normal direct IO case of no page cache pages to - * proceeed concurrently without serialisation. - */ - xfs_rw_ilock(ip, XFS_IOLOCK_SHARED); - if ((ioflags & IO_ISDIRECT) && inode->i_mapping->nrpages) { - xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED); - xfs_rw_ilock(ip, XFS_IOLOCK_EXCL); - - if (inode->i_mapping->nrpages) { - ret = -xfs_flushinval_pages(ip, - (iocb->ki_pos & PAGE_CACHE_MASK), - -1, FI_REMAPF_LOCKED); - if (ret) { - xfs_rw_iunlock(ip, XFS_IOLOCK_EXCL); - return ret; - } - } - xfs_rw_ilock_demote(ip, XFS_IOLOCK_EXCL); - } - - trace_xfs_file_read(ip, size, iocb->ki_pos, ioflags); - - ret = generic_file_aio_read(iocb, iovp, nr_segs, iocb->ki_pos); - if (ret > 0) - XFS_STATS_ADD(xs_read_bytes, ret); - - xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED); - return ret; -} - -STATIC ssize_t -xfs_file_splice_read( - struct file *infilp, - loff_t *ppos, - struct pipe_inode_info *pipe, - size_t count, - unsigned int flags) -{ - struct xfs_inode *ip = XFS_I(infilp->f_mapping->host); - int ioflags = 0; - ssize_t ret; - - XFS_STATS_INC(xs_read_calls); - - if (infilp->f_mode & FMODE_NOCMTIME) - ioflags |= IO_INVIS; - - if (XFS_FORCED_SHUTDOWN(ip->i_mount)) - return -EIO; - - xfs_rw_ilock(ip, XFS_IOLOCK_SHARED); - - trace_xfs_file_splice_read(ip, count, *ppos, ioflags); - - ret = generic_file_splice_read(infilp, ppos, pipe, count, flags); - if (ret > 0) - XFS_STATS_ADD(xs_read_bytes, ret); - - xfs_rw_iunlock(ip, XFS_IOLOCK_SHARED); - return ret; -} - -STATIC void -xfs_aio_write_isize_update( - struct inode *inode, - loff_t *ppos, - ssize_t bytes_written) -{ - struct xfs_inode *ip = XFS_I(inode); - xfs_fsize_t isize = i_size_read(inode); - - if (bytes_written > 0) - XFS_STATS_ADD(xs_write_bytes, bytes_written); - - if (unlikely(bytes_written < 0 && bytes_written != -EFAULT && - *ppos > isize)) - *ppos = isize; - - if (*ppos > ip->i_size) { - xfs_rw_ilock(ip, XFS_ILOCK_EXCL); - if (*ppos > ip->i_size) - ip->i_size = *ppos; - xfs_rw_iunlock(ip, XFS_ILOCK_EXCL); - } -} - -/* - * If this was a direct or synchronous I/O that failed (such as ENOSPC) then - * part of the I/O may have been written to disk before the error occurred. In - * this case the on-disk file size may have been adjusted beyond the in-memory - * file size and now needs to be truncated back. - */ -STATIC void -xfs_aio_write_newsize_update( - struct xfs_inode *ip) -{ - if (ip->i_new_size) { - xfs_rw_ilock(ip, XFS_ILOCK_EXCL); - ip->i_new_size = 0; - if (ip->i_d.di_size > ip->i_size) - ip->i_d.di_size = ip->i_size; - xfs_rw_iunlock(ip, XFS_ILOCK_EXCL); - } -} - -/* - * xfs_file_splice_write() does not use xfs_rw_ilock() because - * generic_file_splice_write() takes the i_mutex itself. This, in theory, - * couuld cause lock inversions between the aio_write path and the splice path - * if someone is doing concurrent splice(2) based writes and write(2) based - * writes to the same inode. The only real way to fix this is to re-implement - * the generic code here with correct locking orders. - */ -STATIC ssize_t -xfs_file_splice_write( - struct pipe_inode_info *pipe, - struct file *outfilp, - loff_t *ppos, - size_t count, - unsigned int flags) -{ - struct inode *inode = outfilp->f_mapping->host; - struct xfs_inode *ip = XFS_I(inode); - xfs_fsize_t new_size; - int ioflags = 0; - ssize_t ret; - - XFS_STATS_INC(xs_write_calls); - - if (outfilp->f_mode & FMODE_NOCMTIME) - ioflags |= IO_INVIS; - - if (XFS_FORCED_SHUTDOWN(ip->i_mount)) - return -EIO; - - xfs_ilock(ip, XFS_IOLOCK_EXCL); - - new_size = *ppos + count; - - xfs_ilock(ip, XFS_ILOCK_EXCL); - if (new_size > ip->i_size) - ip->i_new_size = new_size; - xfs_iunlock(ip, XFS_ILOCK_EXCL); - - trace_xfs_file_splice_write(ip, count, *ppos, ioflags); - - ret = generic_file_splice_write(pipe, outfilp, ppos, count, flags); - - xfs_aio_write_isize_update(inode, ppos, ret); - xfs_aio_write_newsize_update(ip); - xfs_iunlock(ip, XFS_IOLOCK_EXCL); - return ret; -} - -/* - * This routine is called to handle zeroing any space in the last - * block of the file that is beyond the EOF. We do this since the - * size is being increased without writing anything to that block - * and we don't want anyone to read the garbage on the disk. - */ -STATIC int /* error (positive) */ -xfs_zero_last_block( - xfs_inode_t *ip, - xfs_fsize_t offset, - xfs_fsize_t isize) -{ - xfs_fileoff_t last_fsb; - xfs_mount_t *mp = ip->i_mount; - int nimaps; - int zero_offset; - int zero_len; - int error = 0; - xfs_bmbt_irec_t imap; - - ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL)); - - zero_offset = XFS_B_FSB_OFFSET(mp, isize); - if (zero_offset == 0) { - /* - * There are no extra bytes in the last block on disk to - * zero, so return. - */ - return 0; - } - - last_fsb = XFS_B_TO_FSBT(mp, isize); - nimaps = 1; - error = xfs_bmapi(NULL, ip, last_fsb, 1, 0, NULL, 0, &imap, - &nimaps, NULL); - if (error) { - return error; - } - ASSERT(nimaps > 0); - /* - * If the block underlying isize is just a hole, then there - * is nothing to zero. - */ - if (imap.br_startblock == HOLESTARTBLOCK) { - return 0; - } - /* - * Zero the part of the last block beyond the EOF, and write it - * out sync. We need to drop the ilock while we do this so we - * don't deadlock when the buffer cache calls back to us. - */ - xfs_iunlock(ip, XFS_ILOCK_EXCL); - - zero_len = mp->m_sb.sb_blocksize - zero_offset; - if (isize + zero_len > offset) - zero_len = offset - isize; - error = xfs_iozero(ip, isize, zero_len); - - xfs_ilock(ip, XFS_ILOCK_EXCL); - ASSERT(error >= 0); - return error; -} - -/* - * Zero any on disk space between the current EOF and the new, - * larger EOF. This handles the normal case of zeroing the remainder - * of the last block in the file and the unusual case of zeroing blocks - * out beyond the size of the file. This second case only happens - * with fixed size extents and when the system crashes before the inode - * size was updated but after blocks were allocated. If fill is set, - * then any holes in the range are filled and zeroed. If not, the holes - * are left alone as holes. - */ - -int /* error (positive) */ -xfs_zero_eof( - xfs_inode_t *ip, - xfs_off_t offset, /* starting I/O offset */ - xfs_fsize_t isize) /* current inode size */ -{ - xfs_mount_t *mp = ip->i_mount; - xfs_fileoff_t start_zero_fsb; - xfs_fileoff_t end_zero_fsb; - xfs_fileoff_t zero_count_fsb; - xfs_fileoff_t last_fsb; - xfs_fileoff_t zero_off; - xfs_fsize_t zero_len; - int nimaps; - int error = 0; - xfs_bmbt_irec_t imap; - - ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_IOLOCK_EXCL)); - ASSERT(offset > isize); - - /* - * First handle zeroing the block on which isize resides. - * We only zero a part of that block so it is handled specially. - */ - error = xfs_zero_last_block(ip, offset, isize); - if (error) { - ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_IOLOCK_EXCL)); - return error; - } - - /* - * Calculate the range between the new size and the old - * where blocks needing to be zeroed may exist. To get the - * block where the last byte in the file currently resides, - * we need to subtract one from the size and truncate back - * to a block boundary. We subtract 1 in case the size is - * exactly on a block boundary. - */ - last_fsb = isize ? XFS_B_TO_FSBT(mp, isize - 1) : (xfs_fileoff_t)-1; - start_zero_fsb = XFS_B_TO_FSB(mp, (xfs_ufsize_t)isize); - end_zero_fsb = XFS_B_TO_FSBT(mp, offset - 1); - ASSERT((xfs_sfiloff_t)last_fsb < (xfs_sfiloff_t)start_zero_fsb); - if (last_fsb == end_zero_fsb) { - /* - * The size was only incremented on its last block. - * We took care of that above, so just return. - */ - return 0; - } - - ASSERT(start_zero_fsb <= end_zero_fsb); - while (start_zero_fsb <= end_zero_fsb) { - nimaps = 1; - zero_count_fsb = end_zero_fsb - start_zero_fsb + 1; - error = xfs_bmapi(NULL, ip, start_zero_fsb, zero_count_fsb, - 0, NULL, 0, &imap, &nimaps, NULL); - if (error) { - ASSERT(xfs_isilocked(ip, XFS_ILOCK_EXCL|XFS_IOLOCK_EXCL)); - return error; - } - ASSERT(nimaps > 0); - - if (imap.br_state == XFS_EXT_UNWRITTEN || - imap.br_startblock == HOLESTARTBLOCK) { - /* - * This loop handles initializing pages that were - * partially initialized by the code below this - * loop. It basically zeroes the part of the page - * that sits on a hole and sets the page as P_HOLE - * and calls remapf if it is a mapped file. - */ - start_zero_fsb = imap.br_startoff + imap.br_blockcount; - ASSERT(start_zero_fsb <= (end_zero_fsb + 1)); - continue; - } - - /* - * There are blocks we need to zero. - * Drop the inode lock while we're doing the I/O. - * We'll still have the iolock to protect us. - */ - xfs_iunlock(ip, XFS_ILOCK_EXCL); - - zero_off = XFS_FSB_TO_B(mp, start_zero_fsb); - zero_len = XFS_FSB_TO_B(mp, imap.br_blockcount); - - if ((zero_off + zero_len) > offset) - zero_len = offset - zero_off; - - error = xfs_iozero(ip, zero_off, zero_len); - if (error) { - goto out_lock; - } - - start_zero_fsb = imap.br_startoff + imap.br_blockcount; - ASSERT(start_zero_fsb <= (end_zero_fsb + 1)); - - xfs_ilock(ip, XFS_ILOCK_EXCL); - } - - return 0; - -out_lock: - xfs_ilock(ip, XFS_ILOCK_EXCL); - ASSERT(error >= 0); - return error; -} - -/* - * Common pre-write limit and setup checks. - * - * Returns with iolock held according to @iolock. - */ -STATIC ssize_t -xfs_file_aio_write_checks( - struct file *file, - loff_t *pos, - size_t *count, - int *iolock) -{ - struct inode *inode = file->f_mapping->host; - struct xfs_inode *ip = XFS_I(inode); - xfs_fsize_t new_size; - int error = 0; - - xfs_rw_ilock(ip, XFS_ILOCK_EXCL); - error = generic_write_checks(file, pos, count, S_ISBLK(inode->i_mode)); - if (error) { - xfs_rw_iunlock(ip, XFS_ILOCK_EXCL | *iolock); - *iolock = 0; - return error; - } - - new_size = *pos + *count; - if (new_size > ip->i_size) - ip->i_new_size = new_size; - - if (likely(!(file->f_mode & FMODE_NOCMTIME))) - file_update_time(file); - - /* - * If the offset is beyond the size of the file, we need to zero any - * blocks that fall between the existing EOF and the start of this - * write. - */ - if (*pos > ip->i_size) - error = -xfs_zero_eof(ip, *pos, ip->i_size); - - xfs_rw_iunlock(ip, XFS_ILOCK_EXCL); - if (error) - return error; - - /* - * If we're writing the file then make sure to clear the setuid and - * setgid bits if the process is not being run by root. This keeps - * people from modifying setuid and setgid binaries. - */ - return file_remove_suid(file); - -} - -/* - * xfs_file_dio_aio_write - handle direct IO writes - * - * Lock the inode appropriately to prepare for and issue a direct IO write. - * By separating it from the buffered write path we remove all the tricky to - * follow locking changes and looping. - * - * If there are cached pages or we're extending the file, we need IOLOCK_EXCL - * until we're sure the bytes at the new EOF have been zeroed and/or the cached - * pages are flushed out. - * - * In most cases the direct IO writes will be done holding IOLOCK_SHARED - * allowing them to be done in parallel with reads and other direct IO writes. - * However, if the IO is not aligned to filesystem blocks, the direct IO layer - * needs to do sub-block zeroing and that requires serialisation against other - * direct IOs to the same block. In this case we need to serialise the - * submission of the unaligned IOs so that we don't get racing block zeroing in - * the dio layer. To avoid the problem with aio, we also need to wait for - * outstanding IOs to complete so that unwritten extent conversion is completed - * before we try to map the overlapping block. This is currently implemented by - * hitting it with a big hammer (i.e. xfs_ioend_wait()). - * - * Returns with locks held indicated by @iolock and errors indicated by - * negative return values. - */ -STATIC ssize_t -xfs_file_dio_aio_write( - struct kiocb *iocb, - const struct iovec *iovp, - unsigned long nr_segs, - loff_t pos, - size_t ocount, - int *iolock) -{ - struct file *file = iocb->ki_filp; - struct address_space *mapping = file->f_mapping; - struct inode *inode = mapping->host; - struct xfs_inode *ip = XFS_I(inode); - struct xfs_mount *mp = ip->i_mount; - ssize_t ret = 0; - size_t count = ocount; - int unaligned_io = 0; - struct xfs_buftarg *target = XFS_IS_REALTIME_INODE(ip) ? - mp->m_rtdev_targp : mp->m_ddev_targp; - - *iolock = 0; - if ((pos & target->bt_smask) || (count & target->bt_smask)) - return -XFS_ERROR(EINVAL); - - if ((pos & mp->m_blockmask) || ((pos + count) & mp->m_blockmask)) - unaligned_io = 1; - - if (unaligned_io || mapping->nrpages || pos > ip->i_size) - *iolock = XFS_IOLOCK_EXCL; - else - *iolock = XFS_IOLOCK_SHARED; - xfs_rw_ilock(ip, *iolock); - - ret = xfs_file_aio_write_checks(file, &pos, &count, iolock); - if (ret) - return ret; - - /* - * Recheck if there are cached pages that need invalidate after we got - * the iolock to protect against other threads adding new pages while - * we were waiting for the iolock. - */ - if (mapping->nrpages && *iolock == XFS_IOLOCK_SHARED) { - xfs_rw_iunlock(ip, *iolock); - *iolock = XFS_IOLOCK_EXCL; - xfs_rw_ilock(ip, *iolock); - } - - if (mapping->nrpages) { - ret = -xfs_flushinval_pages(ip, (pos & PAGE_CACHE_MASK), -1, - FI_REMAPF_LOCKED); - if (ret) - return ret; - } - - /* - * If we are doing unaligned IO, wait for all other IO to drain, - * otherwise demote the lock if we had to flush cached pages - */ - if (unaligned_io) - xfs_ioend_wait(ip); - else if (*iolock == XFS_IOLOCK_EXCL) { - xfs_rw_ilock_demote(ip, XFS_IOLOCK_EXCL); - *iolock = XFS_IOLOCK_SHARED; - } - - trace_xfs_file_direct_write(ip, count, iocb->ki_pos, 0); - ret = generic_file_direct_write(iocb, iovp, - &nr_segs, pos, &iocb->ki_pos, count, ocount); - - /* No fallback to buffered IO on errors for XFS. */ - ASSERT(ret < 0 || ret == count); - return ret; -} - -STATIC ssize_t -xfs_file_buffered_aio_write( - struct kiocb *iocb, - const struct iovec *iovp, - unsigned long nr_segs, - loff_t pos, - size_t ocount, - int *iolock) -{ - struct file *file = iocb->ki_filp; - struct address_space *mapping = file->f_mapping; - struct inode *inode = mapping->host; - struct xfs_inode *ip = XFS_I(inode); - ssize_t ret; - int enospc = 0; - size_t count = ocount; - - *iolock = XFS_IOLOCK_EXCL; - xfs_rw_ilock(ip, *iolock); - - ret = xfs_file_aio_write_checks(file, &pos, &count, iolock); - if (ret) - return ret; - - /* We can write back this queue in page reclaim */ - current->backing_dev_info = mapping->backing_dev_info; - -write_retry: - trace_xfs_file_buffered_write(ip, count, iocb->ki_pos, 0); - ret = generic_file_buffered_write(iocb, iovp, nr_segs, - pos, &iocb->ki_pos, count, ret); - /* - * if we just got an ENOSPC, flush the inode now we aren't holding any - * page locks and retry *once* - */ - if (ret == -ENOSPC && !enospc) { - ret = -xfs_flush_pages(ip, 0, -1, 0, FI_NONE); - if (ret) - return ret; - enospc = 1; - goto write_retry; - } - current->backing_dev_info = NULL; - return ret; -} - -STATIC ssize_t -xfs_file_aio_write( - struct kiocb *iocb, - const struct iovec *iovp, - 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 xfs_inode *ip = XFS_I(inode); - ssize_t ret; - int iolock; - size_t ocount = 0; - - XFS_STATS_INC(xs_write_calls); - - BUG_ON(iocb->ki_pos != pos); - - ret = generic_segment_checks(iovp, &nr_segs, &ocount, VERIFY_READ); - if (ret) - return ret; - - if (ocount == 0) - return 0; - - xfs_wait_for_freeze(ip->i_mount, SB_FREEZE_WRITE); - - if (XFS_FORCED_SHUTDOWN(ip->i_mount)) - return -EIO; - - if (unlikely(file->f_flags & O_DIRECT)) - ret = xfs_file_dio_aio_write(iocb, iovp, nr_segs, pos, - ocount, &iolock); - else - ret = xfs_file_buffered_aio_write(iocb, iovp, nr_segs, pos, - ocount, &iolock); - - xfs_aio_write_isize_update(inode, &iocb->ki_pos, ret); - - if (ret <= 0) - goto out_unlock; - - /* Handle various SYNC-type writes */ - if ((file->f_flags & O_DSYNC) || IS_SYNC(inode)) { - loff_t end = pos + ret - 1; - int error, error2; - - xfs_rw_iunlock(ip, iolock); - error = filemap_write_and_wait_range(mapping, pos, end); - xfs_rw_ilock(ip, iolock); - - error2 = -xfs_file_fsync(file, - (file->f_flags & __O_SYNC) ? 0 : 1); - if (error) - ret = error; - else if (error2) - ret = error2; - } - -out_unlock: - xfs_aio_write_newsize_update(ip); - xfs_rw_iunlock(ip, iolock); - return ret; -} - -STATIC long -xfs_file_fallocate( - struct file *file, - int mode, - loff_t offset, - loff_t len) -{ - struct inode *inode = file->f_path.dentry->d_inode; - long error; - loff_t new_size = 0; - xfs_flock64_t bf; - xfs_inode_t *ip = XFS_I(inode); - int cmd = XFS_IOC_RESVSP; - int attr_flags = XFS_ATTR_NOLOCK; - - if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE)) - return -EOPNOTSUPP; - - bf.l_whence = 0; - bf.l_start = offset; - bf.l_len = len; - - xfs_ilock(ip, XFS_IOLOCK_EXCL); - - if (mode & FALLOC_FL_PUNCH_HOLE) - cmd = XFS_IOC_UNRESVSP; - - /* check the new inode size is valid before allocating */ - if (!(mode & FALLOC_FL_KEEP_SIZE) && - offset + len > i_size_read(inode)) { - new_size = offset + len; - error = inode_newsize_ok(inode, new_size); - if (error) - goto out_unlock; - } - - if (file->f_flags & O_DSYNC) - attr_flags |= XFS_ATTR_SYNC; - - error = -xfs_change_file_space(ip, cmd, &bf, 0, attr_flags); - if (error) - goto out_unlock; - - /* Change file size if needed */ - if (new_size) { - struct iattr iattr; - - iattr.ia_valid = ATTR_SIZE; - iattr.ia_size = new_size; - error = -xfs_setattr(ip, &iattr, XFS_ATTR_NOLOCK); - } - -out_unlock: - xfs_iunlock(ip, XFS_IOLOCK_EXCL); - return error; -} - - -STATIC int -xfs_file_open( - struct inode *inode, - struct file *file) -{ - if (!(file->f_flags & O_LARGEFILE) && i_size_read(inode) > MAX_NON_LFS) - return -EFBIG; - if (XFS_FORCED_SHUTDOWN(XFS_M(inode->i_sb))) - return -EIO; - return 0; -} - -STATIC int -xfs_dir_open( - struct inode *inode, - struct file *file) -{ - struct xfs_inode *ip = XFS_I(inode); - int mode; - int error; - - error = xfs_file_open(inode, file); - if (error) - return error; - - /* - * If there are any blocks, read-ahead block 0 as we're almost - * certain to have the next operation be a read there. - */ - mode = xfs_ilock_map_shared(ip); - if (ip->i_d.di_nextents > 0) - xfs_da_reada_buf(NULL, ip, 0, XFS_DATA_FORK); - xfs_iunlock(ip, mode); - return 0; -} - -STATIC int -xfs_file_release( - struct inode *inode, - struct file *filp) -{ - return -xfs_release(XFS_I(inode)); -} - -STATIC int -xfs_file_readdir( - struct file *filp, - void *dirent, - filldir_t filldir) -{ - struct inode *inode = filp->f_path.dentry->d_inode; - xfs_inode_t *ip = XFS_I(inode); - int error; - size_t bufsize; - - /* - * The Linux API doesn't pass down the total size of the buffer - * we read into down to the filesystem. With the filldir concept - * it's not needed for correct information, but the XFS dir2 leaf - * code wants an estimate of the buffer size to calculate it's - * readahead window and size the buffers used for mapping to - * physical blocks. - * - * Try to give it an estimate that's good enough, maybe at some - * point we can change the ->readdir prototype to include the - * buffer size. For now we use the current glibc buffer size. - */ - bufsize = (size_t)min_t(loff_t, 32768, ip->i_d.di_size); - - error = xfs_readdir(ip, dirent, bufsize, - (xfs_off_t *)&filp->f_pos, filldir); - if (error) - return -error; - return 0; -} - -STATIC int -xfs_file_mmap( - struct file *filp, - struct vm_area_struct *vma) -{ - vma->vm_ops = &xfs_file_vm_ops; - vma->vm_flags |= VM_CAN_NONLINEAR; - - file_accessed(filp); - return 0; -} - -/* - * mmap()d file has taken write protection fault and is being made - * writable. We can set the page state up correctly for a writable - * page, which means we can do correct delalloc accounting (ENOSPC - * checking!) and unwritten extent mapping. - */ -STATIC int -xfs_vm_page_mkwrite( - struct vm_area_struct *vma, - struct vm_fault *vmf) -{ - return block_page_mkwrite(vma, vmf, xfs_get_blocks); -} - -const struct file_operations xfs_file_operations = { - .llseek = generic_file_llseek, - .read = do_sync_read, - .write = do_sync_write, - .aio_read = xfs_file_aio_read, - .aio_write = xfs_file_aio_write, - .splice_read = xfs_file_splice_read, - .splice_write = xfs_file_splice_write, - .unlocked_ioctl = xfs_file_ioctl, -#ifdef CONFIG_COMPAT - .compat_ioctl = xfs_file_compat_ioctl, -#endif - .mmap = xfs_file_mmap, - .open = xfs_file_open, - .release = xfs_file_release, - .fsync = xfs_file_fsync, - .fallocate = xfs_file_fallocate, -}; - -const struct file_operations xfs_dir_file_operations = { - .open = xfs_dir_open, - .read = generic_read_dir, - .readdir = xfs_file_readdir, - .llseek = generic_file_llseek, - .unlocked_ioctl = xfs_file_ioctl, -#ifdef CONFIG_COMPAT - .compat_ioctl = xfs_file_compat_ioctl, -#endif - .fsync = xfs_file_fsync, -}; - -static const struct vm_operations_struct xfs_file_vm_ops = { - .fault = filemap_fault, - .page_mkwrite = xfs_vm_page_mkwrite, -}; |