diff options
Diffstat (limited to 'fs/gfs2/file.c')
| -rw-r--r-- | fs/gfs2/file.c | 162 |
1 files changed, 153 insertions, 9 deletions
diff --git a/fs/gfs2/file.c b/fs/gfs2/file.c index 8cb278ee9a0e..f3c6d78659b1 100644 --- a/fs/gfs2/file.c +++ b/fs/gfs2/file.c @@ -26,10 +26,12 @@ #include <linux/dlm.h> #include <linux/dlm_plock.h> #include <linux/delay.h> +#include <linux/backing-dev.h> #include "gfs2.h" #include "incore.h" #include "bmap.h" +#include "aops.h" #include "dir.h" #include "glock.h" #include "glops.h" @@ -688,12 +690,89 @@ static int gfs2_fsync(struct file *file, loff_t start, loff_t end, return ret ? ret : ret1; } +static ssize_t gfs2_file_direct_read(struct kiocb *iocb, struct iov_iter *to) +{ + struct file *file = iocb->ki_filp; + struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); + size_t count = iov_iter_count(to); + struct gfs2_holder gh; + ssize_t ret; + + if (!count) + return 0; /* skip atime */ + + gfs2_holder_init(ip->i_gl, LM_ST_DEFERRED, 0, &gh); + ret = gfs2_glock_nq(&gh); + if (ret) + goto out_uninit; + + /* fall back to buffered I/O for stuffed files */ + ret = -ENOTBLK; + if (gfs2_is_stuffed(ip)) + goto out; + + ret = iomap_dio_rw(iocb, to, &gfs2_iomap_ops, NULL); + +out: + gfs2_glock_dq(&gh); +out_uninit: + gfs2_holder_uninit(&gh); + return ret; +} + +static ssize_t gfs2_file_direct_write(struct kiocb *iocb, struct iov_iter *from) +{ + struct file *file = iocb->ki_filp; + struct inode *inode = file->f_mapping->host; + struct gfs2_inode *ip = GFS2_I(inode); + size_t len = iov_iter_count(from); + loff_t offset = iocb->ki_pos; + struct gfs2_holder gh; + ssize_t ret; + + /* + * Deferred lock, even if its a write, since we do no allocation on + * this path. All we need to change is the atime, and this lock mode + * ensures that other nodes have flushed their buffered read caches + * (i.e. their page cache entries for this inode). We do not, + * unfortunately, have the option of only flushing a range like the + * VFS does. + */ + gfs2_holder_init(ip->i_gl, LM_ST_DEFERRED, 0, &gh); + ret = gfs2_glock_nq(&gh); + if (ret) + goto out_uninit; + + /* Silently fall back to buffered I/O when writing beyond EOF */ + if (offset + len > i_size_read(&ip->i_inode)) + goto out; + + ret = iomap_dio_rw(iocb, from, &gfs2_iomap_ops, NULL); + +out: + gfs2_glock_dq(&gh); +out_uninit: + gfs2_holder_uninit(&gh); + return ret; +} + +static ssize_t gfs2_file_read_iter(struct kiocb *iocb, struct iov_iter *to) +{ + ssize_t ret; + + if (iocb->ki_flags & IOCB_DIRECT) { + ret = gfs2_file_direct_read(iocb, to); + if (likely(ret != -ENOTBLK)) + return ret; + iocb->ki_flags &= ~IOCB_DIRECT; + } + return generic_file_read_iter(iocb, to); +} + /** * gfs2_file_write_iter - Perform a write to a file * @iocb: The io context - * @iov: The data to write - * @nr_segs: Number of @iov segments - * @pos: The file position + * @from: The data to write * * We have to do a lock/unlock here to refresh the inode size for * O_APPEND writes, otherwise we can land up writing at the wrong @@ -705,8 +784,9 @@ static int gfs2_fsync(struct file *file, loff_t start, loff_t end, static ssize_t gfs2_file_write_iter(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; - struct gfs2_inode *ip = GFS2_I(file_inode(file)); - int ret; + struct inode *inode = file_inode(file); + struct gfs2_inode *ip = GFS2_I(inode); + ssize_t written = 0, ret; ret = gfs2_rsqa_alloc(ip); if (ret) @@ -723,7 +803,71 @@ static ssize_t gfs2_file_write_iter(struct kiocb *iocb, struct iov_iter *from) gfs2_glock_dq_uninit(&gh); } - return generic_file_write_iter(iocb, from); + inode_lock(inode); + ret = generic_write_checks(iocb, from); + if (ret <= 0) + goto out; + + /* We can write back this queue in page reclaim */ + current->backing_dev_info = inode_to_bdi(inode); + + ret = file_remove_privs(file); + if (ret) + goto out2; + + ret = file_update_time(file); + if (ret) + goto out2; + + if (iocb->ki_flags & IOCB_DIRECT) { + struct address_space *mapping = file->f_mapping; + loff_t pos, endbyte; + ssize_t buffered; + + written = gfs2_file_direct_write(iocb, from); + if (written < 0 || !iov_iter_count(from)) + goto out2; + + ret = iomap_file_buffered_write(iocb, from, &gfs2_iomap_ops); + if (unlikely(ret < 0)) + goto out2; + buffered = ret; + + /* + * We need to ensure that the page cache pages are written to + * disk and invalidated to preserve the expected O_DIRECT + * semantics. + */ + pos = iocb->ki_pos; + endbyte = pos + buffered - 1; + ret = filemap_write_and_wait_range(mapping, pos, endbyte); + if (!ret) { + iocb->ki_pos += buffered; + written += buffered; + invalidate_mapping_pages(mapping, + pos >> PAGE_SHIFT, + endbyte >> PAGE_SHIFT); + } else { + /* + * We don't know how much we wrote, so just return + * the number of bytes which were direct-written + */ + } + } else { + ret = iomap_file_buffered_write(iocb, from, &gfs2_iomap_ops); + if (likely(ret > 0)) + iocb->ki_pos += ret; + } + +out2: + current->backing_dev_info = NULL; +out: + inode_unlock(inode); + if (likely(ret > 0)) { + /* Handle various SYNC-type writes */ + ret = generic_write_sync(iocb, ret); + } + return written ? written : ret; } static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len, @@ -754,7 +898,7 @@ static int fallocate_chunk(struct inode *inode, loff_t offset, loff_t len, if (error) goto out; offset = iomap.offset + iomap.length; - if (iomap.type != IOMAP_HOLE) + if (!(iomap.flags & IOMAP_F_NEW)) continue; error = sb_issue_zeroout(sb, iomap.addr >> inode->i_blkbits, iomap.length >> inode->i_blkbits, @@ -1125,7 +1269,7 @@ static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl) const struct file_operations gfs2_file_fops = { .llseek = gfs2_llseek, - .read_iter = generic_file_read_iter, + .read_iter = gfs2_file_read_iter, .write_iter = gfs2_file_write_iter, .unlocked_ioctl = gfs2_ioctl, .mmap = gfs2_mmap, @@ -1155,7 +1299,7 @@ const struct file_operations gfs2_dir_fops = { const struct file_operations gfs2_file_fops_nolock = { .llseek = gfs2_llseek, - .read_iter = generic_file_read_iter, + .read_iter = gfs2_file_read_iter, .write_iter = gfs2_file_write_iter, .unlocked_ioctl = gfs2_ioctl, .mmap = gfs2_mmap, |