/* * Copyright (C) Sistina Software, Inc. 1997-2003 All rights reserved. * Copyright (C) 2004-2006 Red Hat, Inc. All rights reserved. * * This copyrighted material is made available to anyone wishing to use, * modify, copy, or redistribute it subject to the terms and conditions * of the GNU General Public License version 2. */ #include <linux/slab.h> #include <linux/spinlock.h> #include <linux/completion.h> #include <linux/buffer_head.h> #include <linux/pagemap.h> #include <linux/uio.h> #include <linux/blkdev.h> #include <linux/mm.h> #include <linux/mount.h> #include <linux/fs.h> #include <linux/gfs2_ondisk.h> #include <linux/ext2_fs.h> #include <linux/crc32.h> #include <linux/writeback.h> #include <asm/uaccess.h> #include <linux/dlm.h> #include <linux/dlm_plock.h> #include "gfs2.h" #include "incore.h" #include "bmap.h" #include "dir.h" #include "glock.h" #include "glops.h" #include "inode.h" #include "log.h" #include "meta_io.h" #include "quota.h" #include "rgrp.h" #include "trans.h" #include "util.h" /** * gfs2_llseek - seek to a location in a file * @file: the file * @offset: the offset * @origin: Where to seek from (SEEK_SET, SEEK_CUR, or SEEK_END) * * SEEK_END requires the glock for the file because it references the * file's size. * * Returns: The new offset, or errno */ static loff_t gfs2_llseek(struct file *file, loff_t offset, int origin) { struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); struct gfs2_holder i_gh; loff_t error; if (origin == 2) { error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh); if (!error) { error = generic_file_llseek_unlocked(file, offset, origin); gfs2_glock_dq_uninit(&i_gh); } } else error = generic_file_llseek_unlocked(file, offset, origin); return error; } /** * gfs2_readdir - Read directory entries from a directory * @file: The directory to read from * @dirent: Buffer for dirents * @filldir: Function used to do the copying * * Returns: errno */ static int gfs2_readdir(struct file *file, void *dirent, filldir_t filldir) { struct inode *dir = file->f_mapping->host; struct gfs2_inode *dip = GFS2_I(dir); struct gfs2_holder d_gh; u64 offset = file->f_pos; int error; gfs2_holder_init(dip->i_gl, LM_ST_SHARED, 0, &d_gh); error = gfs2_glock_nq(&d_gh); if (error) { gfs2_holder_uninit(&d_gh); return error; } error = gfs2_dir_read(dir, &offset, dirent, filldir); gfs2_glock_dq_uninit(&d_gh); file->f_pos = offset; return error; } /** * fsflags_cvt * @table: A table of 32 u32 flags * @val: a 32 bit value to convert * * This function can be used to convert between fsflags values and * GFS2's own flags values. * * Returns: the converted flags */ static u32 fsflags_cvt(const u32 *table, u32 val) { u32 res = 0; while(val) { if (val & 1) res |= *table; table++; val >>= 1; } return res; } static const u32 fsflags_to_gfs2[32] = { [3] = GFS2_DIF_SYNC, [4] = GFS2_DIF_IMMUTABLE, [5] = GFS2_DIF_APPENDONLY, [7] = GFS2_DIF_NOATIME, [12] = GFS2_DIF_EXHASH, [14] = GFS2_DIF_INHERIT_JDATA, }; static const u32 gfs2_to_fsflags[32] = { [gfs2fl_Sync] = FS_SYNC_FL, [gfs2fl_Immutable] = FS_IMMUTABLE_FL, [gfs2fl_AppendOnly] = FS_APPEND_FL, [gfs2fl_NoAtime] = FS_NOATIME_FL, [gfs2fl_ExHash] = FS_INDEX_FL, [gfs2fl_InheritJdata] = FS_JOURNAL_DATA_FL, }; static int gfs2_get_flags(struct file *filp, u32 __user *ptr) { struct inode *inode = filp->f_path.dentry->d_inode; struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_holder gh; int error; u32 fsflags; gfs2_holder_init(ip->i_gl, LM_ST_SHARED, 0, &gh); error = gfs2_glock_nq(&gh); if (error) return error; fsflags = fsflags_cvt(gfs2_to_fsflags, ip->i_diskflags); if (!S_ISDIR(inode->i_mode) && ip->i_diskflags & GFS2_DIF_JDATA) fsflags |= FS_JOURNAL_DATA_FL; if (put_user(fsflags, ptr)) error = -EFAULT; gfs2_glock_dq(&gh); gfs2_holder_uninit(&gh); return error; } void gfs2_set_inode_flags(struct inode *inode) { struct gfs2_inode *ip = GFS2_I(inode); unsigned int flags = inode->i_flags; flags &= ~(S_SYNC|S_APPEND|S_IMMUTABLE|S_NOATIME|S_DIRSYNC); if (ip->i_diskflags & GFS2_DIF_IMMUTABLE) flags |= S_IMMUTABLE; if (ip->i_diskflags & GFS2_DIF_APPENDONLY) flags |= S_APPEND; if (ip->i_diskflags & GFS2_DIF_NOATIME) flags |= S_NOATIME; if (ip->i_diskflags & GFS2_DIF_SYNC) flags |= S_SYNC; inode->i_flags = flags; } /* Flags that can be set by user space */ #define GFS2_FLAGS_USER_SET (GFS2_DIF_JDATA| \ GFS2_DIF_IMMUTABLE| \ GFS2_DIF_APPENDONLY| \ GFS2_DIF_NOATIME| \ GFS2_DIF_SYNC| \ GFS2_DIF_SYSTEM| \ GFS2_DIF_INHERIT_JDATA) /** * gfs2_set_flags - set flags on an inode * @inode: The inode * @flags: The flags to set * @mask: Indicates which flags are valid * */ static int do_gfs2_set_flags(struct file *filp, u32 reqflags, u32 mask) { struct inode *inode = filp->f_path.dentry->d_inode; struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_sbd *sdp = GFS2_SB(inode); struct buffer_head *bh; struct gfs2_holder gh; int error; u32 new_flags, flags; error = mnt_want_write(filp->f_path.mnt); if (error) return error; error = gfs2_glock_nq_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); if (error) goto out_drop_write; flags = ip->i_diskflags; new_flags = (flags & ~mask) | (reqflags & mask); if ((new_flags ^ flags) == 0) goto out; error = -EINVAL; if ((new_flags ^ flags) & ~GFS2_FLAGS_USER_SET) goto out; error = -EPERM; if (IS_IMMUTABLE(inode) && (new_flags & GFS2_DIF_IMMUTABLE)) goto out; if (IS_APPEND(inode) && (new_flags & GFS2_DIF_APPENDONLY)) goto out; if (((new_flags ^ flags) & GFS2_DIF_IMMUTABLE) && !capable(CAP_LINUX_IMMUTABLE)) goto out; if (!IS_IMMUTABLE(inode)) { error = gfs2_permission(inode, MAY_WRITE); if (error) goto out; } if ((flags ^ new_flags) & GFS2_DIF_JDATA) { if (flags & GFS2_DIF_JDATA) gfs2_log_flush(sdp, ip->i_gl); error = filemap_fdatawrite(inode->i_mapping); if (error) goto out; error = filemap_fdatawait(inode->i_mapping); if (error) goto out; } error = gfs2_trans_begin(sdp, RES_DINODE, 0); if (error) goto out; error = gfs2_meta_inode_buffer(ip, &bh); if (error) goto out_trans_end; gfs2_trans_add_bh(ip->i_gl, bh, 1); ip->i_diskflags = new_flags; gfs2_dinode_out(ip, bh->b_data); brelse(bh); gfs2_set_inode_flags(inode); gfs2_set_aops(inode); out_trans_end: gfs2_trans_end(sdp); out: gfs2_glock_dq_uninit(&gh); out_drop_write: mnt_drop_write(filp->f_path.mnt); return error; } static int gfs2_set_flags(struct file *filp, u32 __user *ptr) { struct inode *inode = filp->f_path.dentry->d_inode; u32 fsflags, gfsflags; if (get_user(fsflags, ptr)) return -EFAULT; gfsflags = fsflags_cvt(fsflags_to_gfs2, fsflags); if (!S_ISDIR(inode->i_mode)) { if (gfsflags & GFS2_DIF_INHERIT_JDATA) gfsflags ^= (GFS2_DIF_JDATA | GFS2_DIF_INHERIT_JDATA); return do_gfs2_set_flags(filp, gfsflags, ~0); } return do_gfs2_set_flags(filp, gfsflags, ~GFS2_DIF_JDATA); } static long gfs2_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) { switch(cmd) { case FS_IOC_GETFLAGS: return gfs2_get_flags(filp, (u32 __user *)arg); case FS_IOC_SETFLAGS: return gfs2_set_flags(filp, (u32 __user *)arg); } return -ENOTTY; } /** * gfs2_allocate_page_backing - Use bmap to allocate blocks * @page: The (locked) page to allocate backing for * * We try to allocate all the blocks required for the page in * one go. This might fail for various reasons, so we keep * trying until all the blocks to back this page are allocated. * If some of the blocks are already allocated, thats ok too. */ static int gfs2_allocate_page_backing(struct page *page) { struct inode *inode = page->mapping->host; struct buffer_head bh; unsigned long size = PAGE_CACHE_SIZE; u64 lblock = page->index << (PAGE_CACHE_SHIFT - inode->i_blkbits); do { bh.b_state = 0; bh.b_size = size; gfs2_block_map(inode, lblock, &bh, 1); if (!buffer_mapped(&bh)) return -EIO; size -= bh.b_size; lblock += (bh.b_size >> inode->i_blkbits); } while(size > 0); return 0; } /** * gfs2_page_mkwrite - Make a shared, mmap()ed, page writable * @vma: The virtual memory area * @page: The page which is about to become writable * * When the page becomes writable, we need to ensure that we have * blocks allocated on disk to back that page. */ static int gfs2_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) { struct page *page = vmf->page; struct inode *inode = vma->vm_file->f_path.dentry->d_inode; struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_sbd *sdp = GFS2_SB(inode); unsigned long last_index; u64 pos = page->index << PAGE_CACHE_SHIFT; unsigned int data_blocks, ind_blocks, rblocks; int alloc_required = 0; struct gfs2_holder gh; struct gfs2_alloc *al; int ret; gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &gh); ret = gfs2_glock_nq(&gh); if (ret) goto out; set_bit(GLF_DIRTY, &ip->i_gl->gl_flags); set_bit(GIF_SW_PAGED, &ip->i_flags); ret = gfs2_write_alloc_required(ip, pos, PAGE_CACHE_SIZE, &alloc_required); if (ret || !alloc_required) goto out_unlock; ret = -ENOMEM; al = gfs2_alloc_get(ip); if (al == NULL) goto out_unlock; ret = gfs2_quota_lock_check(ip); if (ret) goto out_alloc_put; gfs2_write_calc_reserv(ip, PAGE_CACHE_SIZE, &data_blocks, &ind_blocks); al->al_requested = data_blocks + ind_blocks; ret = gfs2_inplace_reserve(ip); if (ret) goto out_quota_unlock; rblocks = RES_DINODE + ind_blocks; if (gfs2_is_jdata(ip)) rblocks += data_blocks ? data_blocks : 1; if (ind_blocks || data_blocks) rblocks += RES_STATFS + RES_QUOTA; ret = gfs2_trans_begin(sdp, rblocks, 0); if (ret) goto out_trans_fail; lock_page(page); ret = -EINVAL; last_index = ip->i_inode.i_size >> PAGE_CACHE_SHIFT; if (page->index > last_index) goto out_unlock_page; ret = 0; if (!PageUptodate(page) || page->mapping != ip->i_inode.i_mapping) goto out_unlock_page; if (gfs2_is_stuffed(ip)) { ret = gfs2_unstuff_dinode(ip, page); if (ret) goto out_unlock_page; } ret = gfs2_allocate_page_backing(page); out_unlock_page: unlock_page(page); gfs2_trans_end(sdp); out_trans_fail: gfs2_inplace_release(ip); out_quota_unlock: gfs2_quota_unlock(ip); out_alloc_put: gfs2_alloc_put(ip); out_unlock: gfs2_glock_dq(&gh); out: gfs2_holder_uninit(&gh); if (ret == -ENOMEM) ret = VM_FAULT_OOM; else if (ret) ret = VM_FAULT_SIGBUS; return ret; } static struct vm_operations_struct gfs2_vm_ops = { .fault = filemap_fault, .page_mkwrite = gfs2_page_mkwrite, }; /** * gfs2_mmap - * @file: The file to map * @vma: The VMA which described the mapping * * There is no need to get a lock here unless we should be updating * atime. We ignore any locking errors since the only consequence is * a missed atime update (which will just be deferred until later). * * Returns: 0 */ static int gfs2_mmap(struct file *file, struct vm_area_struct *vma) { struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); if (!(file->f_flags & O_NOATIME)) { struct gfs2_holder i_gh; int error; gfs2_holder_init(ip->i_gl, LM_ST_EXCLUSIVE, 0, &i_gh); error = gfs2_glock_nq(&i_gh); file_accessed(file); if (error == 0) gfs2_glock_dq_uninit(&i_gh); } vma->vm_ops = &gfs2_vm_ops; vma->vm_flags |= VM_CAN_NONLINEAR; return 0; } /** * gfs2_open - open a file * @inode: the inode to open * @file: the struct file for this opening * * Returns: errno */ static int gfs2_open(struct inode *inode, struct file *file) { struct gfs2_inode *ip = GFS2_I(inode); struct gfs2_holder i_gh; struct gfs2_file *fp; int error; fp = kzalloc(sizeof(struct gfs2_file), GFP_KERNEL); if (!fp) return -ENOMEM; mutex_init(&fp->f_fl_mutex); gfs2_assert_warn(GFS2_SB(inode), !file->private_data); file->private_data = fp; if (S_ISREG(ip->i_inode.i_mode)) { error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY, &i_gh); if (error) goto fail; if (!(file->f_flags & O_LARGEFILE) && ip->i_disksize > MAX_NON_LFS) { error = -EOVERFLOW; goto fail_gunlock; } gfs2_glock_dq_uninit(&i_gh); } return 0; fail_gunlock: gfs2_glock_dq_uninit(&i_gh); fail: file->private_data = NULL; kfree(fp); return error; } /** * gfs2_close - called to close a struct file * @inode: the inode the struct file belongs to * @file: the struct file being closed * * Returns: errno */ static int gfs2_close(struct inode *inode, struct file *file) { struct gfs2_sbd *sdp = inode->i_sb->s_fs_info; struct gfs2_file *fp; fp = file->private_data; file->private_data = NULL; if (gfs2_assert_warn(sdp, fp)) return -EIO; kfree(fp); return 0; } /** * gfs2_fsync - sync the dirty data for a file (across the cluster) * @file: the file that points to the dentry (we ignore this) * @dentry: the dentry that points to the inode to sync * * The VFS will flush "normal" data for us. We only need to worry * about metadata here. For journaled data, we just do a log flush * as we can't avoid it. Otherwise we can just bale out if datasync * is set. For stuffed inodes we must flush the log in order to * ensure that all data is on disk. * * The call to write_inode_now() is there to write back metadata and * the inode itself. It does also try and write the data, but thats * (hopefully) a no-op due to the VFS having already called filemap_fdatawrite() * for us. * * Returns: errno */ static int gfs2_fsync(struct file *file, struct dentry *dentry, int datasync) { struct inode *inode = dentry->d_inode; int sync_state = inode->i_state & (I_DIRTY_SYNC|I_DIRTY_DATASYNC); int ret = 0; if (gfs2_is_jdata(GFS2_I(inode))) { gfs2_log_flush(GFS2_SB(inode), GFS2_I(inode)->i_gl); return 0; } if (sync_state != 0) { if (!datasync) ret = write_inode_now(inode, 0); if (gfs2_is_stuffed(GFS2_I(inode))) gfs2_log_flush(GFS2_SB(inode), GFS2_I(inode)->i_gl); } return ret; } #ifdef CONFIG_GFS2_FS_LOCKING_DLM /** * gfs2_setlease - acquire/release a file lease * @file: the file pointer * @arg: lease type * @fl: file lock * * We don't currently have a way to enforce a lease across the whole * cluster; until we do, disable leases (by just returning -EINVAL), * unless the administrator has requested purely local locking. * * Returns: errno */ static int gfs2_setlease(struct file *file, long arg, struct file_lock **fl) { return -EINVAL; } /** * gfs2_lock - acquire/release a posix lock on a file * @file: the file pointer * @cmd: either modify or retrieve lock state, possibly wait * @fl: type and range of lock * * Returns: errno */ static int gfs2_lock(struct file *file, int cmd, struct file_lock *fl) { struct gfs2_inode *ip = GFS2_I(file->f_mapping->host); struct gfs2_sbd *sdp = GFS2_SB(file->f_mapping->host); struct lm_lockstruct *ls = &sdp->sd_lockstruct; if (!(fl->fl_flags & FL_POSIX)) return -ENOLCK; if (__mandatory_lock(&ip->i_inode)) return -ENOLCK; if (cmd == F_CANCELLK) { /* Hack: */ cmd = F_SETLK; fl->fl_type = F_UNLCK; } if (unlikely(test_bit(SDF_SHUTDOWN, &sdp->sd_flags))) return -EIO; if (IS_GETLK(cmd)) return dlm_posix_get(ls->ls_dlm, ip->i_no_addr, file, fl); else if (fl->fl_type == F_UNLCK) return dlm_posix_unlock(ls->ls_dlm, ip->i_no_addr, file, fl); else return dlm_posix_lock(ls->ls_dlm, ip->i_no_addr, file, cmd, fl); } static int do_flock(struct file *file, int cmd, struct file_lock *fl) { struct gfs2_file *fp = file->private_data; struct gfs2_holder *fl_gh = &fp->f_fl_gh; struct gfs2_inode *ip = GFS2_I(file->f_path.dentry->d_inode); struct gfs2_glock *gl; unsigned int state; int flags; int error = 0; state = (fl->fl_type == F_WRLCK) ? LM_ST_EXCLUSIVE : LM_ST_SHARED; flags = (IS_SETLKW(cmd) ? 0 : LM_FLAG_TRY) | GL_EXACT | GL_NOCACHE; mutex_lock(&fp->f_fl_mutex); gl = fl_gh->gh_gl; if (gl) { if (fl_gh->gh_state == state) goto out; flock_lock_file_wait(file, &(struct file_lock){.fl_type = F_UNLCK}); gfs2_glock_dq_wait(fl_gh); gfs2_holder_reinit(state, flags, fl_gh); } else { error = gfs2_glock_get(GFS2_SB(&ip->i_inode), ip->i_no_addr, &gfs2_flock_glops, CREATE, &gl); if (error) goto out; gfs2_holder_init(gl, state, flags, fl_gh); gfs2_glock_put(gl); } error = gfs2_glock_nq(fl_gh); if (error) { gfs2_holder_uninit(fl_gh); if (error == GLR_TRYFAILED) error = -EAGAIN; } else { error = flock_lock_file_wait(file, fl); gfs2_assert_warn(GFS2_SB(&ip->i_inode), !error); } out: mutex_unlock(&fp->f_fl_mutex); return error; } static void do_unflock(struct file *file, struct file_lock *fl) { struct gfs2_file *fp = file->private_data; struct gfs2_holder *fl_gh = &fp->f_fl_gh; mutex_lock(&fp->f_fl_mutex); flock_lock_file_wait(file, fl); if (fl_gh->gh_gl) gfs2_glock_dq_uninit(fl_gh); mutex_unlock(&fp->f_fl_mutex); } /** * gfs2_flock - acquire/release a flock lock on a file * @file: the file pointer * @cmd: either modify or retrieve lock state, possibly wait * @fl: type and range of lock * * Returns: errno */ static int gfs2_flock(struct file *file, int cmd, struct file_lock *fl) { if (!(fl->fl_flags & FL_FLOCK)) return -ENOLCK; if (fl->fl_type & LOCK_MAND) return -EOPNOTSUPP; if (fl->fl_type == F_UNLCK) { do_unflock(file, fl); return 0; } else { return do_flock(file, cmd, fl); } } const struct file_operations gfs2_file_fops = { .llseek = gfs2_llseek, .read = do_sync_read, .aio_read = generic_file_aio_read, .write = do_sync_write, .aio_write = generic_file_aio_write, .unlocked_ioctl = gfs2_ioctl, .mmap = gfs2_mmap, .open = gfs2_open, .release = gfs2_close, .fsync = gfs2_fsync, .lock = gfs2_lock, .flock = gfs2_flock, .splice_read = generic_file_splice_read, .splice_write = generic_file_splice_write, .setlease = gfs2_setlease, }; const struct file_operations gfs2_dir_fops = { .readdir = gfs2_readdir, .unlocked_ioctl = gfs2_ioctl, .open = gfs2_open, .release = gfs2_close, .fsync = gfs2_fsync, .lock = gfs2_lock, .flock = gfs2_flock, }; #endif /* CONFIG_GFS2_FS_LOCKING_DLM */ const struct file_operations gfs2_file_fops_nolock = { .llseek = gfs2_llseek, .read = do_sync_read, .aio_read = generic_file_aio_read, .write = do_sync_write, .aio_write = generic_file_aio_write, .unlocked_ioctl = gfs2_ioctl, .mmap = gfs2_mmap, .open = gfs2_open, .release = gfs2_close, .fsync = gfs2_fsync, .splice_read = generic_file_splice_read, .splice_write = generic_file_splice_write, .setlease = generic_setlease, }; const struct file_operations gfs2_dir_fops_nolock = { .readdir = gfs2_readdir, .unlocked_ioctl = gfs2_ioctl, .open = gfs2_open, .release = gfs2_close, .fsync = gfs2_fsync, };