#include <linux/ceph/ceph_debug.h> #include <linux/module.h> #include <linux/sched.h> #include <linux/slab.h> #include <linux/file.h> #include <linux/namei.h> #include <linux/writeback.h> #include "super.h" #include "mds_client.h" /* * Ceph file operations * * Implement basic open/close functionality, and implement * read/write. * * We implement three modes of file I/O: * - buffered uses the generic_file_aio_{read,write} helpers * * - synchronous is used when there is multi-client read/write * sharing, avoids the page cache, and synchronously waits for an * ack from the OSD. * * - direct io takes the variant of the sync path that references * user pages directly. * * fsync() flushes and waits on dirty pages, but just queues metadata * for writeback: since the MDS can recover size and mtime there is no * need to wait for MDS acknowledgement. */ /* * Prepare an open request. Preallocate ceph_cap to avoid an * inopportune ENOMEM later. */ static struct ceph_mds_request * prepare_open_request(struct super_block *sb, int flags, int create_mode) { struct ceph_fs_client *fsc = ceph_sb_to_client(sb); struct ceph_mds_client *mdsc = fsc->mdsc; struct ceph_mds_request *req; int want_auth = USE_ANY_MDS; int op = (flags & O_CREAT) ? CEPH_MDS_OP_CREATE : CEPH_MDS_OP_OPEN; if (flags & (O_WRONLY|O_RDWR|O_CREAT|O_TRUNC)) want_auth = USE_AUTH_MDS; req = ceph_mdsc_create_request(mdsc, op, want_auth); if (IS_ERR(req)) goto out; req->r_fmode = ceph_flags_to_mode(flags); req->r_args.open.flags = cpu_to_le32(flags); req->r_args.open.mode = cpu_to_le32(create_mode); req->r_args.open.preferred = cpu_to_le32(-1); out: return req; } /* * initialize private struct file data. * if we fail, clean up by dropping fmode reference on the ceph_inode */ static int ceph_init_file(struct inode *inode, struct file *file, int fmode) { struct ceph_file_info *cf; int ret = 0; switch (inode->i_mode & S_IFMT) { case S_IFREG: case S_IFDIR: dout("init_file %p %p 0%o (regular)\n", inode, file, inode->i_mode); cf = kmem_cache_alloc(ceph_file_cachep, GFP_NOFS | __GFP_ZERO); if (cf == NULL) { ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */ return -ENOMEM; } cf->fmode = fmode; cf->next_offset = 2; file->private_data = cf; BUG_ON(inode->i_fop->release != ceph_release); break; case S_IFLNK: dout("init_file %p %p 0%o (symlink)\n", inode, file, inode->i_mode); ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */ break; default: dout("init_file %p %p 0%o (special)\n", inode, file, inode->i_mode); /* * we need to drop the open ref now, since we don't * have .release set to ceph_release. */ ceph_put_fmode(ceph_inode(inode), fmode); /* clean up */ BUG_ON(inode->i_fop->release == ceph_release); /* call the proper open fop */ ret = inode->i_fop->open(inode, file); } return ret; } /* * If the filp already has private_data, that means the file was * already opened by intent during lookup, and we do nothing. * * If we already have the requisite capabilities, we can satisfy * the open request locally (no need to request new caps from the * MDS). We do, however, need to inform the MDS (asynchronously) * if our wanted caps set expands. */ int ceph_open(struct inode *inode, struct file *file) { struct ceph_inode_info *ci = ceph_inode(inode); struct ceph_fs_client *fsc = ceph_sb_to_client(inode->i_sb); struct ceph_mds_client *mdsc = fsc->mdsc; struct ceph_mds_request *req; struct ceph_file_info *cf = file->private_data; struct inode *parent_inode = NULL; int err; int flags, fmode, wanted; if (cf) { dout("open file %p is already opened\n", file); return 0; } /* filter out O_CREAT|O_EXCL; vfs did that already. yuck. */ flags = file->f_flags & ~(O_CREAT|O_EXCL); if (S_ISDIR(inode->i_mode)) flags = O_DIRECTORY; /* mds likes to know */ dout("open inode %p ino %llx.%llx file %p flags %d (%d)\n", inode, ceph_vinop(inode), file, flags, file->f_flags); fmode = ceph_flags_to_mode(flags); wanted = ceph_caps_for_mode(fmode); /* snapped files are read-only */ if (ceph_snap(inode) != CEPH_NOSNAP && (file->f_mode & FMODE_WRITE)) return -EROFS; /* trivially open snapdir */ if (ceph_snap(inode) == CEPH_SNAPDIR) { spin_lock(&ci->i_ceph_lock); __ceph_get_fmode(ci, fmode); spin_unlock(&ci->i_ceph_lock); return ceph_init_file(inode, file, fmode); } /* * No need to block if we have caps on the auth MDS (for * write) or any MDS (for read). Update wanted set * asynchronously. */ spin_lock(&ci->i_ceph_lock); if (__ceph_is_any_real_caps(ci) && (((fmode & CEPH_FILE_MODE_WR) == 0) || ci->i_auth_cap)) { int mds_wanted = __ceph_caps_mds_wanted(ci); int issued = __ceph_caps_issued(ci, NULL); dout("open %p fmode %d want %s issued %s using existing\n", inode, fmode, ceph_cap_string(wanted), ceph_cap_string(issued)); __ceph_get_fmode(ci, fmode); spin_unlock(&ci->i_ceph_lock); /* adjust wanted? */ if ((issued & wanted) != wanted && (mds_wanted & wanted) != wanted && ceph_snap(inode) != CEPH_SNAPDIR) ceph_check_caps(ci, 0, NULL); return ceph_init_file(inode, file, fmode); } else if (ceph_snap(inode) != CEPH_NOSNAP && (ci->i_snap_caps & wanted) == wanted) { __ceph_get_fmode(ci, fmode); spin_unlock(&ci->i_ceph_lock); return ceph_init_file(inode, file, fmode); } spin_unlock(&ci->i_ceph_lock); dout("open fmode %d wants %s\n", fmode, ceph_cap_string(wanted)); req = prepare_open_request(inode->i_sb, flags, 0); if (IS_ERR(req)) { err = PTR_ERR(req); goto out; } req->r_inode = inode; ihold(inode); req->r_num_caps = 1; if (flags & (O_CREAT|O_TRUNC)) parent_inode = ceph_get_dentry_parent_inode(file->f_dentry); err = ceph_mdsc_do_request(mdsc, parent_inode, req); iput(parent_inode); if (!err) err = ceph_init_file(inode, file, req->r_fmode); ceph_mdsc_put_request(req); dout("open result=%d on %llx.%llx\n", err, ceph_vinop(inode)); out: return err; } /* * Do a lookup + open with a single request. * * If this succeeds, but some subsequent check in the vfs * may_open() fails, the struct *file gets cleaned up (i.e. * ceph_release gets called). So fear not! */ /* * flags * path_lookup_open -> LOOKUP_OPEN * path_lookup_create -> LOOKUP_OPEN|LOOKUP_CREATE */ struct dentry *ceph_lookup_open(struct inode *dir, struct dentry *dentry, struct nameidata *nd, int mode, int locked_dir) { struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb); struct ceph_mds_client *mdsc = fsc->mdsc; struct file *file; struct ceph_mds_request *req; struct dentry *ret; int err; int flags = nd->intent.open.flags; dout("ceph_lookup_open dentry %p '%.*s' flags %d mode 0%o\n", dentry, dentry->d_name.len, dentry->d_name.name, flags, mode); /* do the open */ req = prepare_open_request(dir->i_sb, flags, mode); if (IS_ERR(req)) return ERR_CAST(req); req->r_dentry = dget(dentry); req->r_num_caps = 2; if (flags & O_CREAT) { req->r_dentry_drop = CEPH_CAP_FILE_SHARED; req->r_dentry_unless = CEPH_CAP_FILE_EXCL; } req->r_locked_dir = dir; /* caller holds dir->i_mutex */ err = ceph_mdsc_do_request(mdsc, (flags & (O_CREAT|O_TRUNC)) ? dir : NULL, req); err = ceph_handle_snapdir(req, dentry, err); if (err) goto out; if ((flags & O_CREAT) && !req->r_reply_info.head->is_dentry) err = ceph_handle_notrace_create(dir, dentry); if (err) goto out; file = lookup_instantiate_filp(nd, req->r_dentry, ceph_open); if (IS_ERR(file)) err = PTR_ERR(file); out: ret = ceph_finish_lookup(req, dentry, err); ceph_mdsc_put_request(req); dout("ceph_lookup_open result=%p\n", ret); return ret; } int ceph_release(struct inode *inode, struct file *file) { struct ceph_inode_info *ci = ceph_inode(inode); struct ceph_file_info *cf = file->private_data; dout("release inode %p file %p\n", inode, file); ceph_put_fmode(ci, cf->fmode); if (cf->last_readdir) ceph_mdsc_put_request(cf->last_readdir); kfree(cf->last_name); kfree(cf->dir_info); dput(cf->dentry); kmem_cache_free(ceph_file_cachep, cf); /* wake up anyone waiting for caps on this inode */ wake_up_all(&ci->i_cap_wq); return 0; } /* * Read a range of bytes striped over one or more objects. Iterate over * objects we stripe over. (That's not atomic, but good enough for now.) * * If we get a short result from the OSD, check against i_size; we need to * only return a short read to the caller if we hit EOF. */ static int striped_read(struct inode *inode, u64 off, u64 len, struct page **pages, int num_pages, int *checkeof, bool o_direct, unsigned long buf_align) { struct ceph_fs_client *fsc = ceph_inode_to_client(inode); struct ceph_inode_info *ci = ceph_inode(inode); u64 pos, this_len; int io_align, page_align; int left, pages_left; int read; struct page **page_pos; int ret; bool hit_stripe, was_short; /* * we may need to do multiple reads. not atomic, unfortunately. */ pos = off; left = len; page_pos = pages; pages_left = num_pages; read = 0; io_align = off & ~PAGE_MASK; more: if (o_direct) page_align = (pos - io_align + buf_align) & ~PAGE_MASK; else page_align = pos & ~PAGE_MASK; this_len = left; ret = ceph_osdc_readpages(&fsc->client->osdc, ceph_vino(inode), &ci->i_layout, pos, &this_len, ci->i_truncate_seq, ci->i_truncate_size, page_pos, pages_left, page_align); if (ret == -ENOENT) ret = 0; hit_stripe = this_len < left; was_short = ret >= 0 && ret < this_len; dout("striped_read %llu~%u (read %u) got %d%s%s\n", pos, left, read, ret, hit_stripe ? " HITSTRIPE" : "", was_short ? " SHORT" : ""); if (ret > 0) { int didpages = (page_align + ret) >> PAGE_CACHE_SHIFT; if (read < pos - off) { dout(" zero gap %llu to %llu\n", off + read, pos); ceph_zero_page_vector_range(page_align + read, pos - off - read, pages); } pos += ret; read = pos - off; left -= ret; page_pos += didpages; pages_left -= didpages; /* hit stripe? */ if (left && hit_stripe) goto more; } if (was_short) { /* did we bounce off eof? */ if (pos + left > inode->i_size) *checkeof = 1; /* zero trailing bytes (inside i_size) */ if (left > 0 && pos < inode->i_size) { if (pos + left > inode->i_size) left = inode->i_size - pos; dout("zero tail %d\n", left); ceph_zero_page_vector_range(page_align + read, left, pages); read += left; } } if (ret >= 0) ret = read; dout("striped_read returns %d\n", ret); return ret; } /* * Completely synchronous read and write methods. Direct from __user * buffer to osd, or directly to user pages (if O_DIRECT). * * If the read spans object boundary, just do multiple reads. */ static ssize_t ceph_sync_read(struct file *file, char __user *data, unsigned len, loff_t *poff, int *checkeof) { struct inode *inode = file->f_dentry->d_inode; struct page **pages; u64 off = *poff; int num_pages, ret; dout("sync_read on file %p %llu~%u %s\n", file, off, len, (file->f_flags & O_DIRECT) ? "O_DIRECT" : ""); if (file->f_flags & O_DIRECT) { num_pages = calc_pages_for((unsigned long)data, len); pages = ceph_get_direct_page_vector(data, num_pages, true); } else { num_pages = calc_pages_for(off, len); pages = ceph_alloc_page_vector(num_pages, GFP_NOFS); } if (IS_ERR(pages)) return PTR_ERR(pages); /* * flush any page cache pages in this range. this * will make concurrent normal and sync io slow, * but it will at least behave sensibly when they are * in sequence. */ ret = filemap_write_and_wait(inode->i_mapping); if (ret < 0) goto done; ret = striped_read(inode, off, len, pages, num_pages, checkeof, file->f_flags & O_DIRECT, (unsigned long)data & ~PAGE_MASK); if (ret >= 0 && (file->f_flags & O_DIRECT) == 0) ret = ceph_copy_page_vector_to_user(pages, data, off, ret); if (ret >= 0) *poff = off + ret; done: if (file->f_flags & O_DIRECT) ceph_put_page_vector(pages, num_pages, true); else ceph_release_page_vector(pages, num_pages); dout("sync_read result %d\n", ret); return ret; } /* * Write commit callback, called if we requested both an ACK and * ONDISK commit reply from the OSD. */ static void sync_write_commit(struct ceph_osd_request *req, struct ceph_msg *msg) { struct ceph_inode_info *ci = ceph_inode(req->r_inode); dout("sync_write_commit %p tid %llu\n", req, req->r_tid); spin_lock(&ci->i_unsafe_lock); list_del_init(&req->r_unsafe_item); spin_unlock(&ci->i_unsafe_lock); ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR); } /* * Synchronous write, straight from __user pointer or user pages (if * O_DIRECT). * * If write spans object boundary, just do multiple writes. (For a * correct atomic write, we should e.g. take write locks on all * objects, rollback on failure, etc.) */ static ssize_t ceph_sync_write(struct file *file, const char __user *data, size_t left, loff_t *offset) { struct inode *inode = file->f_dentry->d_inode; struct ceph_inode_info *ci = ceph_inode(inode); struct ceph_fs_client *fsc = ceph_inode_to_client(inode); struct ceph_osd_request *req; struct page **pages; int num_pages; long long unsigned pos; u64 len; int written = 0; int flags; int do_sync = 0; int check_caps = 0; int page_align, io_align; unsigned long buf_align; int ret; struct timespec mtime = CURRENT_TIME; if (ceph_snap(file->f_dentry->d_inode) != CEPH_NOSNAP) return -EROFS; dout("sync_write on file %p %lld~%u %s\n", file, *offset, (unsigned)left, (file->f_flags & O_DIRECT) ? "O_DIRECT" : ""); if (file->f_flags & O_APPEND) pos = i_size_read(inode); else pos = *offset; ret = filemap_write_and_wait_range(inode->i_mapping, pos, pos + left); if (ret < 0) return ret; ret = invalidate_inode_pages2_range(inode->i_mapping, pos >> PAGE_CACHE_SHIFT, (pos + left) >> PAGE_CACHE_SHIFT); if (ret < 0) dout("invalidate_inode_pages2_range returned %d\n", ret); flags = CEPH_OSD_FLAG_ORDERSNAP | CEPH_OSD_FLAG_ONDISK | CEPH_OSD_FLAG_WRITE; if ((file->f_flags & (O_SYNC|O_DIRECT)) == 0) flags |= CEPH_OSD_FLAG_ACK; else do_sync = 1; /* * we may need to do multiple writes here if we span an object * boundary. this isn't atomic, unfortunately. :( */ more: io_align = pos & ~PAGE_MASK; buf_align = (unsigned long)data & ~PAGE_MASK; len = left; if (file->f_flags & O_DIRECT) { /* write from beginning of first page, regardless of io alignment */ page_align = (pos - io_align + buf_align) & ~PAGE_MASK; num_pages = calc_pages_for((unsigned long)data, len); } else { page_align = pos & ~PAGE_MASK; num_pages = calc_pages_for(pos, len); } req = ceph_osdc_new_request(&fsc->client->osdc, &ci->i_layout, ceph_vino(inode), pos, &len, CEPH_OSD_OP_WRITE, flags, ci->i_snap_realm->cached_context, do_sync, ci->i_truncate_seq, ci->i_truncate_size, &mtime, false, 2, page_align); if (!req) return -ENOMEM; if (file->f_flags & O_DIRECT) { pages = ceph_get_direct_page_vector(data, num_pages, false); if (IS_ERR(pages)) { ret = PTR_ERR(pages); goto out; } /* * throw out any page cache pages in this range. this * may block. */ truncate_inode_pages_range(inode->i_mapping, pos, (pos+len) | (PAGE_CACHE_SIZE-1)); } else { pages = ceph_alloc_page_vector(num_pages, GFP_NOFS); if (IS_ERR(pages)) { ret = PTR_ERR(pages); goto out; } ret = ceph_copy_user_to_page_vector(pages, data, pos, len); if (ret < 0) { ceph_release_page_vector(pages, num_pages); goto out; } if ((file->f_flags & O_SYNC) == 0) { /* get a second commit callback */ req->r_safe_callback = sync_write_commit; req->r_own_pages = 1; } } req->r_pages = pages; req->r_num_pages = num_pages; req->r_inode = inode; ret = ceph_osdc_start_request(&fsc->client->osdc, req, false); if (!ret) { if (req->r_safe_callback) { /* * Add to inode unsafe list only after we * start_request so that a tid has been assigned. */ spin_lock(&ci->i_unsafe_lock); list_add_tail(&req->r_unsafe_item, &ci->i_unsafe_writes); spin_unlock(&ci->i_unsafe_lock); ceph_get_cap_refs(ci, CEPH_CAP_FILE_WR); } ret = ceph_osdc_wait_request(&fsc->client->osdc, req); if (ret < 0 && req->r_safe_callback) { spin_lock(&ci->i_unsafe_lock); list_del_init(&req->r_unsafe_item); spin_unlock(&ci->i_unsafe_lock); ceph_put_cap_refs(ci, CEPH_CAP_FILE_WR); } } if (file->f_flags & O_DIRECT) ceph_put_page_vector(pages, num_pages, false); else if (file->f_flags & O_SYNC) ceph_release_page_vector(pages, num_pages); out: ceph_osdc_put_request(req); if (ret == 0) { pos += len; written += len; left -= len; data += written; if (left) goto more; ret = written; *offset = pos; if (pos > i_size_read(inode)) check_caps = ceph_inode_set_size(inode, pos); if (check_caps) ceph_check_caps(ceph_inode(inode), CHECK_CAPS_AUTHONLY, NULL); } return ret; } /* * Wrap generic_file_aio_read with checks for cap bits on the inode. * Atomically grab references, so that those bits are not released * back to the MDS mid-read. * * Hmm, the sync read case isn't actually async... should it be? */ static ssize_t ceph_aio_read(struct kiocb *iocb, const struct iovec *iov, unsigned long nr_segs, loff_t pos) { struct file *filp = iocb->ki_filp; struct ceph_file_info *fi = filp->private_data; loff_t *ppos = &iocb->ki_pos; size_t len = iov->iov_len; struct inode *inode = filp->f_dentry->d_inode; struct ceph_inode_info *ci = ceph_inode(inode); void __user *base = iov->iov_base; ssize_t ret; int want, got = 0; int checkeof = 0, read = 0; dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n", inode, ceph_vinop(inode), pos, (unsigned)len, inode); again: __ceph_do_pending_vmtruncate(inode); if (fi->fmode & CEPH_FILE_MODE_LAZY) want = CEPH_CAP_FILE_CACHE | CEPH_CAP_FILE_LAZYIO; else want = CEPH_CAP_FILE_CACHE; ret = ceph_get_caps(ci, CEPH_CAP_FILE_RD, want, &got, -1); if (ret < 0) goto out; dout("aio_read %p %llx.%llx %llu~%u got cap refs on %s\n", inode, ceph_vinop(inode), pos, (unsigned)len, ceph_cap_string(got)); if ((got & (CEPH_CAP_FILE_CACHE|CEPH_CAP_FILE_LAZYIO)) == 0 || (iocb->ki_filp->f_flags & O_DIRECT) || (inode->i_sb->s_flags & MS_SYNCHRONOUS) || (fi->flags & CEPH_F_SYNC)) /* hmm, this isn't really async... */ ret = ceph_sync_read(filp, base, len, ppos, &checkeof); else ret = generic_file_aio_read(iocb, iov, nr_segs, pos); out: dout("aio_read %p %llx.%llx dropping cap refs on %s = %d\n", inode, ceph_vinop(inode), ceph_cap_string(got), (int)ret); ceph_put_cap_refs(ci, got); if (checkeof && ret >= 0) { int statret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE); /* hit EOF or hole? */ if (statret == 0 && *ppos < inode->i_size) { dout("aio_read sync_read hit hole, ppos %lld < size %lld, reading more\n", *ppos, inode->i_size); read += ret; base += ret; len -= ret; checkeof = 0; goto again; } } if (ret >= 0) ret += read; return ret; } /* * Take cap references to avoid releasing caps to MDS mid-write. * * If we are synchronous, and write with an old snap context, the OSD * may return EOLDSNAPC. In that case, retry the write.. _after_ * dropping our cap refs and allowing the pending snap to logically * complete _before_ this write occurs. * * If we are near ENOSPC, write synchronously. */ static ssize_t ceph_aio_write(struct kiocb *iocb, const struct iovec *iov, unsigned long nr_segs, loff_t pos) { struct file *file = iocb->ki_filp; struct ceph_file_info *fi = file->private_data; struct inode *inode = file->f_dentry->d_inode; struct ceph_inode_info *ci = ceph_inode(inode); struct ceph_osd_client *osdc = &ceph_sb_to_client(inode->i_sb)->client->osdc; loff_t endoff = pos + iov->iov_len; int want, got = 0; int ret, err; if (ceph_snap(inode) != CEPH_NOSNAP) return -EROFS; retry_snap: if (ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_FULL)) return -ENOSPC; __ceph_do_pending_vmtruncate(inode); dout("aio_write %p %llx.%llx %llu~%u getting caps. i_size %llu\n", inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len, inode->i_size); if (fi->fmode & CEPH_FILE_MODE_LAZY) want = CEPH_CAP_FILE_BUFFER | CEPH_CAP_FILE_LAZYIO; else want = CEPH_CAP_FILE_BUFFER; ret = ceph_get_caps(ci, CEPH_CAP_FILE_WR, want, &got, endoff); if (ret < 0) goto out_put; dout("aio_write %p %llx.%llx %llu~%u got cap refs on %s\n", inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len, ceph_cap_string(got)); if ((got & (CEPH_CAP_FILE_BUFFER|CEPH_CAP_FILE_LAZYIO)) == 0 || (iocb->ki_filp->f_flags & O_DIRECT) || (inode->i_sb->s_flags & MS_SYNCHRONOUS) || (fi->flags & CEPH_F_SYNC)) { ret = ceph_sync_write(file, iov->iov_base, iov->iov_len, &iocb->ki_pos); } else { /* * buffered write; drop Fw early to avoid slow * revocation if we get stuck on balance_dirty_pages */ int dirty; spin_lock(&ci->i_ceph_lock); dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR); spin_unlock(&ci->i_ceph_lock); ceph_put_cap_refs(ci, got); ret = generic_file_aio_write(iocb, iov, nr_segs, pos); if ((ret >= 0 || ret == -EIOCBQUEUED) && ((file->f_flags & O_SYNC) || IS_SYNC(file->f_mapping->host) || ceph_osdmap_flag(osdc->osdmap, CEPH_OSDMAP_NEARFULL))) { err = vfs_fsync_range(file, pos, pos + ret - 1, 1); if (err < 0) ret = err; } if (dirty) __mark_inode_dirty(inode, dirty); goto out; } if (ret >= 0) { int dirty; spin_lock(&ci->i_ceph_lock); dirty = __ceph_mark_dirty_caps(ci, CEPH_CAP_FILE_WR); spin_unlock(&ci->i_ceph_lock); if (dirty) __mark_inode_dirty(inode, dirty); } out_put: dout("aio_write %p %llx.%llx %llu~%u dropping cap refs on %s\n", inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len, ceph_cap_string(got)); ceph_put_cap_refs(ci, got); out: if (ret == -EOLDSNAPC) { dout("aio_write %p %llx.%llx %llu~%u got EOLDSNAPC, retrying\n", inode, ceph_vinop(inode), pos, (unsigned)iov->iov_len); goto retry_snap; } return ret; } /* * llseek. be sure to verify file size on SEEK_END. */ static loff_t ceph_llseek(struct file *file, loff_t offset, int origin) { struct inode *inode = file->f_mapping->host; int ret; mutex_lock(&inode->i_mutex); __ceph_do_pending_vmtruncate(inode); if (origin == SEEK_END || origin == SEEK_DATA || origin == SEEK_HOLE) { ret = ceph_do_getattr(inode, CEPH_STAT_CAP_SIZE); if (ret < 0) { offset = ret; goto out; } } switch (origin) { case SEEK_END: offset += inode->i_size; break; case SEEK_CUR: /* * Here we special-case the lseek(fd, 0, SEEK_CUR) * position-querying operation. Avoid rewriting the "same" * f_pos value back to the file because a concurrent read(), * write() or lseek() might have altered it */ if (offset == 0) { offset = file->f_pos; goto out; } offset += file->f_pos; break; case SEEK_DATA: if (offset >= inode->i_size) { ret = -ENXIO; goto out; } break; case SEEK_HOLE: if (offset >= inode->i_size) { ret = -ENXIO; goto out; } offset = inode->i_size; break; } if (offset < 0 || offset > inode->i_sb->s_maxbytes) { offset = -EINVAL; goto out; } /* Special lock needed here? */ if (offset != file->f_pos) { file->f_pos = offset; file->f_version = 0; } out: mutex_unlock(&inode->i_mutex); return offset; } const struct file_operations ceph_file_fops = { .open = ceph_open, .release = ceph_release, .llseek = ceph_llseek, .read = do_sync_read, .write = do_sync_write, .aio_read = ceph_aio_read, .aio_write = ceph_aio_write, .mmap = ceph_mmap, .fsync = ceph_fsync, .lock = ceph_lock, .flock = ceph_flock, .splice_read = generic_file_splice_read, .splice_write = generic_file_splice_write, .unlocked_ioctl = ceph_ioctl, .compat_ioctl = ceph_ioctl, };