/* * Copyright (C) 2007 Oracle. 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 v2 as published by the Free Software Foundation. * * This program is distributed in the hope that it will 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 to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 021110-1307, USA. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "ctree.h" #include "disk-io.h" #include "transaction.h" #include "btrfs_inode.h" #include "print-tree.h" #include "tree-log.h" #include "locking.h" #include "volumes.h" #include "qgroup.h" static struct kmem_cache *btrfs_inode_defrag_cachep; /* * when auto defrag is enabled we * queue up these defrag structs to remember which * inodes need defragging passes */ struct inode_defrag { struct rb_node rb_node; /* objectid */ u64 ino; /* * transid where the defrag was added, we search for * extents newer than this */ u64 transid; /* root objectid */ u64 root; /* last offset we were able to defrag */ u64 last_offset; /* if we've wrapped around back to zero once already */ int cycled; }; static int __compare_inode_defrag(struct inode_defrag *defrag1, struct inode_defrag *defrag2) { if (defrag1->root > defrag2->root) return 1; else if (defrag1->root < defrag2->root) return -1; else if (defrag1->ino > defrag2->ino) return 1; else if (defrag1->ino < defrag2->ino) return -1; else return 0; } /* pop a record for an inode into the defrag tree. The lock * must be held already * * If you're inserting a record for an older transid than an * existing record, the transid already in the tree is lowered * * If an existing record is found the defrag item you * pass in is freed */ static int __btrfs_add_inode_defrag(struct inode *inode, struct inode_defrag *defrag) { struct btrfs_root *root = BTRFS_I(inode)->root; struct inode_defrag *entry; struct rb_node **p; struct rb_node *parent = NULL; int ret; p = &root->fs_info->defrag_inodes.rb_node; while (*p) { parent = *p; entry = rb_entry(parent, struct inode_defrag, rb_node); ret = __compare_inode_defrag(defrag, entry); if (ret < 0) p = &parent->rb_left; else if (ret > 0) p = &parent->rb_right; else { /* if we're reinserting an entry for * an old defrag run, make sure to * lower the transid of our existing record */ if (defrag->transid < entry->transid) entry->transid = defrag->transid; if (defrag->last_offset > entry->last_offset) entry->last_offset = defrag->last_offset; return -EEXIST; } } set_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags); rb_link_node(&defrag->rb_node, parent, p); rb_insert_color(&defrag->rb_node, &root->fs_info->defrag_inodes); return 0; } static inline int __need_auto_defrag(struct btrfs_root *root) { if (!btrfs_test_opt(root, AUTO_DEFRAG)) return 0; if (btrfs_fs_closing(root->fs_info)) return 0; return 1; } /* * insert a defrag record for this inode if auto defrag is * enabled */ int btrfs_add_inode_defrag(struct btrfs_trans_handle *trans, struct inode *inode) { struct btrfs_root *root = BTRFS_I(inode)->root; struct inode_defrag *defrag; u64 transid; int ret; if (!__need_auto_defrag(root)) return 0; if (test_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags)) return 0; if (trans) transid = trans->transid; else transid = BTRFS_I(inode)->root->last_trans; defrag = kmem_cache_zalloc(btrfs_inode_defrag_cachep, GFP_NOFS); if (!defrag) return -ENOMEM; defrag->ino = btrfs_ino(inode); defrag->transid = transid; defrag->root = root->root_key.objectid; spin_lock(&root->fs_info->defrag_inodes_lock); if (!test_bit(BTRFS_INODE_IN_DEFRAG, &BTRFS_I(inode)->runtime_flags)) { /* * If we set IN_DEFRAG flag and evict the inode from memory, * and then re-read this inode, this new inode doesn't have * IN_DEFRAG flag. At the case, we may find the existed defrag. */ ret = __btrfs_add_inode_defrag(inode, defrag); if (ret) kmem_cache_free(btrfs_inode_defrag_cachep, defrag); } else { kmem_cache_free(btrfs_inode_defrag_cachep, defrag); } spin_unlock(&root->fs_info->defrag_inodes_lock); return 0; } /* * Requeue the defrag object. If there is a defrag object that points to * the same inode in the tree, we will merge them together (by * __btrfs_add_inode_defrag()) and free the one that we want to requeue. */ static void btrfs_requeue_inode_defrag(struct inode *inode, struct inode_defrag *defrag) { struct btrfs_root *root = BTRFS_I(inode)->root; int ret; if (!__need_auto_defrag(root)) goto out; /* * Here we don't check the IN_DEFRAG flag, because we need merge * them together. */ spin_lock(&root->fs_info->defrag_inodes_lock); ret = __btrfs_add_inode_defrag(inode, defrag); spin_unlock(&root->fs_info->defrag_inodes_lock); if (ret) goto out; return; out: kmem_cache_free(btrfs_inode_defrag_cachep, defrag); } /* * pick the defragable inode that we want, if it doesn't exist, we will get * the next one. */ static struct inode_defrag * btrfs_pick_defrag_inode(struct btrfs_fs_info *fs_info, u64 root, u64 ino) { struct inode_defrag *entry = NULL; struct inode_defrag tmp; struct rb_node *p; struct rb_node *parent = NULL; int ret; tmp.ino = ino; tmp.root = root; spin_lock(&fs_info->defrag_inodes_lock); p = fs_info->defrag_inodes.rb_node; while (p) { parent = p; entry = rb_entry(parent, struct inode_defrag, rb_node); ret = __compare_inode_defrag(&tmp, entry); if (ret < 0) p = parent->rb_left; else if (ret > 0) p = parent->rb_right; else goto out; } if (parent && __compare_inode_defrag(&tmp, entry) > 0) { parent = rb_next(parent); if (parent) entry = rb_entry(parent, struct inode_defrag, rb_node); else entry = NULL; } out: if (entry) rb_erase(parent, &fs_info->defrag_inodes); spin_unlock(&fs_info->defrag_inodes_lock); return entry; } void btrfs_cleanup_defrag_inodes(struct btrfs_fs_info *fs_info) { struct inode_defrag *defrag; struct rb_node *node; spin_lock(&fs_info->defrag_inodes_lock); node = rb_first(&fs_info->defrag_inodes); while (node) { rb_erase(node, &fs_info->defrag_inodes); defrag = rb_entry(node, struct inode_defrag, rb_node); kmem_cache_free(btrfs_inode_defrag_cachep, defrag); if (need_resched()) { spin_unlock(&fs_info->defrag_inodes_lock); cond_resched(); spin_lock(&fs_info->defrag_inodes_lock); } node = rb_first(&fs_info->defrag_inodes); } spin_unlock(&fs_info->defrag_inodes_lock); } #define BTRFS_DEFRAG_BATCH 1024 static int __btrfs_run_defrag_inode(struct btrfs_fs_info *fs_info, struct inode_defrag *defrag) { struct btrfs_root *inode_root; struct inode *inode; struct btrfs_key key; struct btrfs_ioctl_defrag_range_args range; int num_defrag; int index; int ret; /* get the inode */ key.objectid = defrag->root; btrfs_set_key_type(&key, BTRFS_ROOT_ITEM_KEY); key.offset = (u64)-1; index = srcu_read_lock(&fs_info->subvol_srcu); inode_root = btrfs_read_fs_root_no_name(fs_info, &key); if (IS_ERR(inode_root)) { ret = PTR_ERR(inode_root); goto cleanup; } key.objectid = defrag->ino; btrfs_set_key_type(&key, BTRFS_INODE_ITEM_KEY); key.offset = 0; inode = btrfs_iget(fs_info->sb, &key, inode_root, NULL); if (IS_ERR(inode)) { ret = PTR_ERR(inode)
#ifndef _ASM_X86_SIGNAL_H
#define _ASM_X86_SIGNAL_H

#ifndef __ASSEMBLY__
#include <linux/linkage.h>

/* Most things should be clean enough to redefine this at will, if care
   is taken to make libc match.  */

#define _NSIG		64

#ifdef __i386__
# define _NSIG_BPW	32
#else
# define _NSIG_BPW	64
#endif

#define _NSIG_WORDS	(_NSIG / _NSIG_BPW)

typedef unsigned long old_sigset_t;		/* at least 32 bits */

typedef struct {
	unsigned long sig[_NSIG_WORDS];
} sigset_t;

/*
 * Because some traps use the IST stack, we must keep preemption
 * disabled while calling do_trap(), but do_trap() may call
 * force_sig_info() which will grab the signal spin_locks for the
 * task, which in PREEMPT_RT_FULL are mutexes.  By defining
 * ARCH_RT_DELAYS_SIGNAL_SEND the force_sig_info() will set
 * TIF_NOTIFY_RESUME and set up the signal to be sent on exit of the
 * trap.
 */
#if defined(CONFIG_PREEMPT_RT_FULL)
#define ARCH_RT_DELAYS_SIGNAL_SEND
#endif

#ifndef CONFIG_COMPAT
typedef sigset_t compat_sigset_t;
#endif

#endif /* __ASSEMBLY__ */
#include <uapi/asm/signal.h>
#ifndef __ASSEMBLY__
extern void do_signal(struct pt_regs *regs);

#define __ARCH_HAS_SA_RESTORER

#include <uapi/asm/sigcontext.h>

#ifdef __i386__

#define __HAVE_ARCH_SIG_BITOPS

#define sigaddset(set,sig)		    \
	(__builtin_constant_p(sig)	    \
	 ? __const_sigaddset((set), (sig))  \
	 : __gen_sigaddset((set), (sig)))

static inline void __gen_sigaddset(sigset_t *set, int _sig)
{
	asm("btsl %1,%0" : "+m"(*set) : "Ir"(_sig - 1) : "cc");
}

static inline void __const_sigaddset(sigset_t *set, int _sig)
{
	unsigned long sig = _sig - 1;
	set->sig[sig / _NSIG_BPW] |= 1 << (sig % _NSIG_BPW);
}

#define sigdelset(set, sig)		    \
	(__builtin_constant_p(sig)	    \
	 ? __const_sigdelset((set), (sig))  \
	 : __gen_sigdelset((set), (sig)))


static inline void __gen_sigdelset(sigset_t *set, int _sig)
{
	asm("btrl %1,%0" : "+m"(*set) : "Ir"(_sig - 1) : "cc");
}

static inline void __const_sigdelset(sigset_t *set, int _sig)
{
	unsigned long sig = _sig - 1;
	set->sig[sig / _NSIG_BPW] &= ~(1 << (sig % _NSIG_BPW));
}

static inline int __const_sigismember(sigset_t *set, int _sig)
{
	unsigned long sig = _sig - 1;
	return 1 & (set->sig[sig / _NSIG_BPW] >> (sig % _NSIG_BPW));
}

static inline int __gen_sigismember(sigset_t *set, int _sig)
{
	unsigned char ret;
	asm("btl %2,%1\n\tsetc %0"
	    : "=qm"(ret) : "m"(*set), "Ir"(_sig-1) : "cc");
	return ret;
}

#define sigismember(set, sig)			\
	(__builtin_constant_p(sig)		\
	 ? __const_sigismember((set), (sig))	\
	 : __gen_sigismember((set), (sig)))

struct pt_regs;

#else /* __i386__ */

#undef __HAVE_ARCH_SIG_BITOPS

#endif /* !__i386__ */

#endif /* __ASSEMBLY__ */
#endif /* _ASM_X86_SIGNAL_H */
generated by cgit 1.2.3-korg (git 2.39.0) at 2024-05-17 01:43:03 +0000
s marked as written, the extent will be split into * two or three. */ int btrfs_mark_extent_written(struct btrfs_trans_handle *trans, struct inode *inode, u64 start, u64 end) { struct btrfs_root *root = BTRFS_I(inode)->root; struct extent_buffer *leaf; struct btrfs_path *path; struct btrfs_file_extent_item *fi; struct btrfs_key key; struct btrfs_key new_key; u64 bytenr; u64 num_bytes; u64 extent_end; u64 orig_offset; u64 other_start; u64 other_end; u64 split; int del_nr = 0; int del_slot = 0; int recow; int ret; u64 ino = btrfs_ino(inode); path = btrfs_alloc_path(); if (!path) return -ENOMEM; again: recow = 0; split = start; key.objectid = ino; key.type = BTRFS_EXTENT_DATA_KEY; key.offset = split; ret = btrfs_search_slot(trans, root, &key, path, -1, 1); if (ret < 0) goto out; if (ret > 0 && path->slots[0] > 0) path->slots[0]--; leaf = path->nodes[0]; btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); BUG_ON(key.objectid != ino || key.type != BTRFS_EXTENT_DATA_KEY); fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); BUG_ON(btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_PREALLOC); extent_end = key.offset + btrfs_file_extent_num_bytes(leaf, fi); BUG_ON(key.offset > start || extent_end < end); bytenr = btrfs_file_extent_disk_bytenr(leaf, fi); num_bytes = btrfs_file_extent_disk_num_bytes(leaf, fi); orig_offset = key.offset - btrfs_file_extent_offset(leaf, fi); memcpy(&new_key, &key, sizeof(new_key)); if (start == key.offset && end < extent_end) { other_start = 0; other_end = start; if (extent_mergeable(leaf, path->slots[0] - 1, ino, bytenr, orig_offset, &other_start, &other_end)) { new_key.offset = end; btrfs_set_item_key_safe(root, path, &new_key); fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); btrfs_set_file_extent_generation(leaf, fi, trans->transid); btrfs_set_file_extent_num_bytes(leaf, fi, extent_end - end); btrfs_set_file_extent_offset(leaf, fi, end - orig_offset); fi = btrfs_item_ptr(leaf, path->slots[0] - 1, struct btrfs_file_extent_item); btrfs_set_file_extent_generation(leaf, fi, trans->transid); btrfs_set_file_extent_num_bytes(leaf, fi, end - other_start); btrfs_mark_buffer_dirty(leaf); goto out; } } if (start > key.offset && end == extent_end) { other_start = end; other_end = 0; if (extent_mergeable(leaf, path->slots[0] + 1, ino, bytenr, orig_offset, &other_start, &other_end)) { fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); btrfs_set_file_extent_num_bytes(leaf, fi, start - key.offset); btrfs_set_file_extent_generation(leaf, fi, trans->transid); path->slots[0]++; new_key.offset = start; btrfs_set_item_key_safe(root, path, &new_key); fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); btrfs_set_file_extent_generation(leaf, fi, trans->transid); btrfs_set_file_extent_num_bytes(leaf, fi, other_end - start); btrfs_set_file_extent_offset(leaf, fi, start - orig_offset); btrfs_mark_buffer_dirty(leaf); goto out; } } while (start > key.offset || end < extent_end) { if (key.offset == start) split = end; new_key.offset = split; ret = btrfs_duplicate_item(trans, root, path, &new_key); if (ret == -EAGAIN) { btrfs_release_path(path); goto again; } if (ret < 0) { btrfs_abort_transaction(trans, root, ret); goto out; } leaf = path->nodes[0]; fi = btrfs_item_ptr(leaf, path->slots[0] - 1, struct btrfs_file_extent_item); btrfs_set_file_extent_generation(leaf, fi, trans->transid); btrfs_set_file_extent_num_bytes(leaf, fi, split - key.offset); fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); btrfs_set_file_extent_generation(leaf, fi, trans->transid); btrfs_set_file_extent_offset(leaf, fi, split - orig_offset); btrfs_set_file_extent_num_bytes(leaf, fi, extent_end - split); btrfs_mark_buffer_dirty(leaf); ret = btrfs_inc_extent_ref(trans, root, bytenr, num_bytes, 0, root->root_key.objectid, ino, orig_offset, 1); BUG_ON(ret); /* -ENOMEM */ if (split == start) { key.offset = start; } else { BUG_ON(start != key.offset); path->slots[0]--; extent_end = end; } recow = 1; } other_start = end; other_end = 0; if (extent_mergeable(leaf, path->slots[0] + 1, ino, bytenr, orig_offset, &other_start, &other_end)) { if (recow) { btrfs_release_path(path); goto again; } extent_end = other_end; del_slot = path->slots[0] + 1; del_nr++; ret = btrfs_free_extent(trans, root, bytenr, num_bytes, 0, root->root_key.objectid, ino, orig_offset, 0); BUG_ON(ret); /* -ENOMEM */ } other_start = 0; other_end = start; if (extent_mergeable(leaf, path->slots[0] - 1, ino, bytenr, orig_offset, &other_start, &other_end)) { if (recow) { btrfs_release_path(path); goto again; } key.offset = other_start; del_slot = path->slots[0]; del_nr++; ret = btrfs_free_extent(trans, root, bytenr, num_bytes, 0, root->root_key.objectid, ino, orig_offset, 0); BUG_ON(ret); /* -ENOMEM */ } if (del_nr == 0) { fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); btrfs_set_file_extent_type(leaf, fi, BTRFS_FILE_EXTENT_REG); btrfs_set_file_extent_generation(leaf, fi, trans->transid); btrfs_mark_buffer_dirty(leaf); } else { fi = btrfs_item_ptr(leaf, del_slot - 1, struct btrfs_file_extent_item); btrfs_set_file_extent_type(leaf, fi, BTRFS_FILE_EXTENT_REG); btrfs_set_file_extent_generation(leaf, fi, trans->transid); btrfs_set_file_extent_num_bytes(leaf, fi, extent_end - key.offset); btrfs_mark_buffer_dirty(leaf); ret = btrfs_del_items(trans, root, path, del_slot, del_nr); if (ret < 0) { btrfs_abort_transaction(trans, root, ret); goto out; } } out: btrfs_free_path(path); return 0; } /* * on error we return an unlocked page and the error value * on success we return a locked page and 0 */ static int prepare_uptodate_page(struct page *page, u64 pos, bool force_uptodate) { int ret = 0; if (((pos & (PAGE_CACHE_SIZE - 1)) || force_uptodate) && !PageUptodate(page)) { ret = btrfs_readpage(NULL, page); if (ret) return ret; lock_page(page); if (!PageUptodate(page)) { unlock_page(page); return -EIO; } } return 0; } /* * this just gets pages into the page cache and locks them down. */ static noinline int prepare_pages(struct inode *inode, struct page **pages, size_t num_pages, loff_t pos, size_t write_bytes, bool force_uptodate) { int i; unsigned long index = pos >> PAGE_CACHE_SHIFT; gfp_t mask = btrfs_alloc_write_mask(inode->i_mapping); int err = 0; int faili; for (i = 0; i < num_pages; i++) { pages[i] = find_or_create_page(inode->i_mapping, index + i, mask | __GFP_WRITE); if (!pages[i]) { faili = i - 1; err = -ENOMEM; goto fail; } if (i == 0) err = prepare_uptodate_page(pages[i], pos, force_uptodate); if (i == num_pages - 1) err = prepare_uptodate_page(pages[i], pos + write_bytes, false); if (err) { page_cache_release(pages[i]); faili = i - 1; goto fail; } wait_on_page_writeback(pages[i]); } return 0; fail: while (faili >= 0) { unlock_page(pages[faili]); page_cache_release(pages[faili]); faili--; } return err; } /* * This function locks the extent and properly waits for data=ordered extents * to finish before allowing the pages to be modified if need. * * The return value: * 1 - the extent is locked * 0 - the extent is not locked, and everything is OK * -EAGAIN - need re-prepare the pages * the other < 0 number - Something wrong happens */ static noinline int lock_and_cleanup_extent_if_need(struct inode *inode, struct page **pages, size_t num_pages, loff_t pos, u64 *lockstart, u64 *lockend, struct extent_state **cached_state) { u64 start_pos; u64 last_pos; int i; int ret = 0; start_pos = pos & ~((u64)PAGE_CACHE_SIZE - 1); last_pos = start_pos + ((u64)num_pages << PAGE_CACHE_SHIFT) - 1; if (start_pos < inode->i_size) { struct btrfs_ordered_extent *ordered; lock_extent_bits(&BTRFS_I(inode)->io_tree, start_pos, last_pos, 0, cached_state); ordered = btrfs_lookup_ordered_range(inode, start_pos, last_pos - start_pos + 1); if (ordered && ordered->file_offset + ordered->len > start_pos && ordered->file_offset <= last_pos) { unlock_extent_cached(&BTRFS_I(inode)->io_tree, start_pos, last_pos, cached_state, GFP_NOFS); for (i = 0; i < num_pages; i++) { unlock_page(pages[i]); page_cache_release(pages[i]); } btrfs_start_ordered_extent(inode, ordered, 1); btrfs_put_ordered_extent(ordered); return -EAGAIN; } if (ordered) btrfs_put_ordered_extent(ordered); clear_extent_bit(&BTRFS_I(inode)->io_tree, start_pos, last_pos, EXTENT_DIRTY | EXTENT_DELALLOC | EXTENT_DO_ACCOUNTING | EXTENT_DEFRAG, 0, 0, cached_state, GFP_NOFS); *lockstart = start_pos; *lockend = last_pos; ret = 1; } for (i = 0; i < num_pages; i++) { if (clear_page_dirty_for_io(pages[i])) account_page_redirty(pages[i]); set_page_extent_mapped(pages[i]); WARN_ON(!PageLocked(pages[i])); } return ret; } static noinline int check_can_nocow(struct inode *inode, loff_t pos, size_t *write_bytes) { struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_ordered_extent *ordered; u64 lockstart, lockend; u64 num_bytes; int ret; ret = btrfs_start_nocow_write(root); if (!ret) return -ENOSPC; lockstart = round_down(pos, root->sectorsize); lockend = round_up(pos + *write_bytes, root->sectorsize) - 1; while (1) { lock_extent(&BTRFS_I(inode)->io_tree, lockstart, lockend); ordered = btrfs_lookup_ordered_range(inode, lockstart, lockend - lockstart + 1); if (!ordered) { break; } unlock_extent(&BTRFS_I(inode)->io_tree, lockstart, lockend); btrfs_start_ordered_extent(inode, ordered, 1); btrfs_put_ordered_extent(ordered); } num_bytes = lockend - lockstart + 1; ret = can_nocow_extent(inode, lockstart, &num_bytes, NULL, NULL, NULL); if (ret <= 0) { ret = 0; btrfs_end_nocow_write(root); } else { *write_bytes = min_t(size_t, *write_bytes , num_bytes - pos + lockstart); } unlock_extent(&BTRFS_I(inode)->io_tree, lockstart, lockend); return ret; } static noinline ssize_t __btrfs_buffered_write(struct file *file, struct iov_iter *i, loff_t pos) { struct inode *inode = file_inode(file); struct btrfs_root *root = BTRFS_I(inode)->root; struct page **pages = NULL; struct extent_state *cached_state = NULL; u64 release_bytes = 0; u64 lockstart; u64 lockend; unsigned long first_index; size_t num_written = 0; int nrptrs; int ret = 0; bool only_release_metadata = false; bool force_page_uptodate = false; bool need_unlock; nrptrs = min((iov_iter_count(i) + PAGE_CACHE_SIZE - 1) / PAGE_CACHE_SIZE, PAGE_CACHE_SIZE / (sizeof(struct page *))); nrptrs = min(nrptrs, current->nr_dirtied_pause - current->nr_dirtied); nrptrs = max(nrptrs, 8); pages = kmalloc(nrptrs * sizeof(struct page *), GFP_KERNEL); if (!pages) return -ENOMEM; first_index = pos >> PAGE_CACHE_SHIFT; while (iov_iter_count(i) > 0) { size_t offset = pos & (PAGE_CACHE_SIZE - 1); size_t write_bytes = min(iov_iter_count(i), nrptrs * (size_t)PAGE_CACHE_SIZE - offset); size_t num_pages = (write_bytes + offset + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; size_t reserve_bytes; size_t dirty_pages; size_t copied; WARN_ON(num_pages > nrptrs); /* * Fault pages before locking them in prepare_pages * to avoid recursive lock */ if (unlikely(iov_iter_fault_in_readable(i, write_bytes))) { ret = -EFAULT; break; } reserve_bytes = num_pages << PAGE_CACHE_SHIFT; ret = btrfs_check_data_free_space(inode, reserve_bytes); if (ret == -ENOSPC && (BTRFS_I(inode)->flags & (BTRFS_INODE_NODATACOW | BTRFS_INODE_PREALLOC))) { ret = check_can_nocow(inode, pos, &write_bytes); if (ret > 0) { only_release_metadata = true; /* * our prealloc extent may be smaller than * write_bytes, so scale down. */ num_pages = (write_bytes + offset + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; reserve_bytes = num_pages << PAGE_CACHE_SHIFT; ret = 0; } else { ret = -ENOSPC; } } if (ret) break; ret = btrfs_delalloc_reserve_metadata(inode, reserve_bytes); if (ret) { if (!only_release_metadata) btrfs_free_reserved_data_space(inode, reserve_bytes); else btrfs_end_nocow_write(root); break; } release_bytes = reserve_bytes; need_unlock = false; again: /* * This is going to setup the pages array with the number of * pages we want, so we don't really need to worry about the * contents of pages from loop to loop */ ret = prepare_pages(inode, pages, num_pages, pos, write_bytes, force_page_uptodate); if (ret) break; ret = lock_and_cleanup_extent_if_need(inode, pages, num_pages, pos, &lockstart, &lockend, &cached_state); if (ret < 0) { if (ret == -EAGAIN) goto again; break; } else if (ret > 0) { need_unlock = true; ret = 0; } copied = btrfs_copy_from_user(pos, num_pages, write_bytes, pages, i); /* * if we have trouble faulting in the pages, fall * back to one page at a time */ if (copied < write_bytes) nrptrs = 1; if (copied == 0) { force_page_uptodate = true; dirty_pages = 0; } else { force_page_uptodate = false; dirty_pages = (copied + offset + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT; } /* * If we had a short copy we need to release the excess delaloc * bytes we reserved. We need to increment outstanding_extents * because btrfs_delalloc_release_space will decrement it, but * we still have an outstanding extent for the chunk we actually * managed to copy. */ if (num_pages > dirty_pages) { release_bytes = (num_pages - dirty_pages) << PAGE_CACHE_SHIFT; if (copied > 0) { spin_lock(&BTRFS_I(inode)->lock); BTRFS_I(inode)->outstanding_extents++; spin_unlock(&BTRFS_I(inode)->lock); } if (only_release_metadata) btrfs_delalloc_release_metadata(inode, release_bytes); else btrfs_delalloc_release_space(inode, release_bytes); } release_bytes = dirty_pages << PAGE_CACHE_SHIFT; if (copied > 0) ret = btrfs_dirty_pages(root, inode, pages, dirty_pages, pos, copied, NULL); if (need_unlock) unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend, &cached_state, GFP_NOFS); if (ret) { btrfs_drop_pages(pages, num_pages); break; } release_bytes = 0; if (only_release_metadata) btrfs_end_nocow_write(root); if (only_release_metadata && copied > 0) { u64 lockstart = round_down(pos, root->sectorsize); u64 lockend = lockstart + (dirty_pages << PAGE_CACHE_SHIFT) - 1; set_extent_bit(&BTRFS_I(inode)->io_tree, lockstart, lockend, EXTENT_NORESERVE, NULL, NULL, GFP_NOFS); only_release_metadata = false; } btrfs_drop_pages(pages, num_pages); cond_resched(); balance_dirty_pages_ratelimited(inode->i_mapping); if (dirty_pages < (root->leafsize >> PAGE_CACHE_SHIFT) + 1) btrfs_btree_balance_dirty(root); pos += copied; num_written += copied; } kfree(pages); if (release_bytes) { if (only_release_metadata) { btrfs_end_nocow_write(root); btrfs_delalloc_release_metadata(inode, release_bytes); } else { btrfs_delalloc_release_space(inode, release_bytes); } } return num_written ? num_written : ret; } static ssize_t __btrfs_direct_write(struct kiocb *iocb, struct iov_iter *from, loff_t pos) { struct file *file = iocb->ki_filp; ssize_t written; ssize_t written_buffered; loff_t endbyte; int err; written = generic_file_direct_write(iocb, from, pos); if (written < 0 || !iov_iter_count(from)) return written; pos += written; written_buffered = __btrfs_buffered_write(file, from, pos); if (written_buffered < 0) { err = written_buffered; goto out; } endbyte = pos + written_buffered - 1; err = filemap_write_and_wait_range(file->f_mapping, pos, endbyte); if (err) goto out; written += written_buffered; iocb->ki_pos = pos + written_buffered; invalidate_mapping_pages(file->f_mapping, pos >> PAGE_CACHE_SHIFT, endbyte >> PAGE_CACHE_SHIFT); out: return written ? written : err; } static void update_time_for_write(struct inode *inode) { struct timespec now; if (IS_NOCMTIME(inode)) return; now = current_fs_time(inode->i_sb); if (!timespec_equal(&inode->i_mtime, &now)) inode->i_mtime = now; if (!timespec_equal(&inode->i_ctime, &now)) inode->i_ctime = now; if (IS_I_VERSION(inode)) inode_inc_iversion(inode); } static ssize_t btrfs_file_write_iter(struct kiocb *iocb, struct iov_iter *from) { struct file *file = iocb->ki_filp; struct inode *inode = file_inode(file); struct btrfs_root *root = BTRFS_I(inode)->root; u64 start_pos; u64 end_pos; ssize_t num_written = 0; ssize_t err = 0; size_t count = iov_iter_count(from); bool sync = (file->f_flags & O_DSYNC) || IS_SYNC(file->f_mapping->host); loff_t pos = iocb->ki_pos; mutex_lock(&inode->i_mutex); current->backing_dev_info = inode->i_mapping->backing_dev_info; err = generic_write_checks(file, &pos, &count, S_ISBLK(inode->i_mode)); if (err) { mutex_unlock(&inode->i_mutex); goto out; } if (count == 0) { mutex_unlock(&inode->i_mutex); goto out; } iov_iter_truncate(from, count); err = file_remove_suid(file); if (err) { mutex_unlock(&inode->i_mutex); goto out; } /* * If BTRFS flips readonly due to some impossible error * (fs_info->fs_state now has BTRFS_SUPER_FLAG_ERROR), * although we have opened a file as writable, we have * to stop this write operation to ensure FS consistency. */ if (test_bit(BTRFS_FS_STATE_ERROR, &root->fs_info->fs_state)) { mutex_unlock(&inode->i_mutex); err = -EROFS; goto out; } /* * We reserve space for updating the inode when we reserve space for the * extent we are going to write, so we will enospc out there. We don't * need to start yet another transaction to update the inode as we will * update the inode when we finish writing whatever data we write. */ update_time_for_write(inode); start_pos = round_down(pos, root->sectorsize); if (start_pos > i_size_read(inode)) { /* Expand hole size to cover write data, preventing empty gap */ end_pos = round_up(pos + count, root->sectorsize); err = btrfs_cont_expand(inode, i_size_read(inode), end_pos); if (err) { mutex_unlock(&inode->i_mutex); goto out; } } if (sync) atomic_inc(&BTRFS_I(inode)->sync_writers); if (unlikely(file->f_flags & O_DIRECT)) { num_written = __btrfs_direct_write(iocb, from, pos); } else { num_written = __btrfs_buffered_write(file, from, pos); if (num_written > 0) iocb->ki_pos = pos + num_written; } mutex_unlock(&inode->i_mutex); /* * we want to make sure fsync finds this change * but we haven't joined a transaction running right now. * * Later on, someone is sure to update the inode and get the * real transid recorded. * * We set last_trans now to the fs_info generation + 1, * this will either be one more than the running transaction * or the generation used for the next transaction if there isn't * one running right now. * * We also have to set last_sub_trans to the current log transid, * otherwise subsequent syncs to a file that's been synced in this * transaction will appear to have already occured. */ BTRFS_I(inode)->last_trans = root->fs_info->generation + 1; BTRFS_I(inode)->last_sub_trans = root->log_transid; if (num_written > 0) { err = generic_write_sync(file, pos, num_written); if (err < 0) num_written = err; } if (sync) atomic_dec(&BTRFS_I(inode)->sync_writers); out: current->backing_dev_info = NULL; return num_written ? num_written : err; } int btrfs_release_file(struct inode *inode, struct file *filp) { if (filp->private_data) btrfs_ioctl_trans_end(filp); /* * ordered_data_close is set by settattr when we are about to truncate * a file from a non-zero size to a zero size. This tries to * flush down new bytes that may have been written if the * application were using truncate to replace a file in place. */ if (test_and_clear_bit(BTRFS_INODE_ORDERED_DATA_CLOSE, &BTRFS_I(inode)->runtime_flags)) filemap_flush(inode->i_mapping); return 0; } /* * fsync call for both files and directories. This logs the inode into * the tree log instead of forcing full commits whenever possible. * * It needs to call filemap_fdatawait so that all ordered extent updates are * in the metadata btree are up to date for copying to the log. * * It drops the inode mutex before doing the tree log commit. This is an * important optimization for directories because holding the mutex prevents * new operations on the dir while we write to disk. */ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync) { struct dentry *dentry = file->f_path.dentry; struct inode *inode = dentry->d_inode; struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; struct btrfs_log_ctx ctx; int ret = 0; bool full_sync = 0; trace_btrfs_sync_file(file, datasync); /* * We write the dirty pages in the range and wait until they complete * out of the ->i_mutex. If so, we can flush the dirty pages by * multi-task, and make the performance up. See * btrfs_wait_ordered_range for an explanation of the ASYNC check. */ atomic_inc(&BTRFS_I(inode)->sync_writers); ret = filemap_fdatawrite_range(inode->i_mapping, start, end); if (!ret && test_bit(BTRFS_INODE_HAS_ASYNC_EXTENT, &BTRFS_I(inode)->runtime_flags)) ret = filemap_fdatawrite_range(inode->i_mapping, start, end); atomic_dec(&BTRFS_I(inode)->sync_writers); if (ret) return ret; mutex_lock(&inode->i_mutex); /* * We flush the dirty pages again to avoid some dirty pages in the * range being left. */ atomic_inc(&root->log_batch); full_sync = test_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); if (full_sync) { ret = btrfs_wait_ordered_range(inode, start, end - start + 1); if (ret) { mutex_unlock(&inode->i_mutex); goto out; } } atomic_inc(&root->log_batch); /* * check the transaction that last modified this inode * and see if its already been committed */ if (!BTRFS_I(inode)->last_trans) { mutex_unlock(&inode->i_mutex); goto out; } /* * if the last transaction that changed this file was before * the current transaction, we can bail out now without any * syncing */ smp_mb(); if (btrfs_inode_in_log(inode, root->fs_info->generation) || BTRFS_I(inode)->last_trans <= root->fs_info->last_trans_committed) { BTRFS_I(inode)->last_trans = 0; /* * We'v had everything committed since the last time we were * modified so clear this flag in case it was set for whatever * reason, it's no longer relevant. */ clear_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); mutex_unlock(&inode->i_mutex); goto out; } /* * ok we haven't committed the transaction yet, lets do a commit */ if (file->private_data) btrfs_ioctl_trans_end(file); /* * We use start here because we will need to wait on the IO to complete * in btrfs_sync_log, which could require joining a transaction (for * example checking cross references in the nocow path). If we use join * here we could get into a situation where we're waiting on IO to * happen that is blocked on a transaction trying to commit. With start * we inc the extwriter counter, so we wait for all extwriters to exit * before we start blocking join'ers. This comment is to keep somebody * from thinking they are super smart and changing this to * btrfs_join_transaction *cough*Josef*cough*. */ trans = btrfs_start_transaction(root, 0); if (IS_ERR(trans)) { ret = PTR_ERR(trans); mutex_unlock(&inode->i_mutex); goto out; } trans->sync = true; btrfs_init_log_ctx(&ctx); ret = btrfs_log_dentry_safe(trans, root, dentry, start, end, &ctx); if (ret < 0) { /* Fallthrough and commit/free transaction. */ ret = 1; } /* we've logged all the items and now have a consistent * version of the file in the log. It is possible that * someone will come in and modify the file, but that's * fine because the log is consistent on disk, and we * have references to all of the file's extents * * It is possible that someone will come in and log the * file again, but that will end up using the synchronization * inside btrfs_sync_log to keep things safe. */ mutex_unlock(&inode->i_mutex); if (ret != BTRFS_NO_LOG_SYNC) { if (!ret) { ret = btrfs_sync_log(trans, root, &ctx); if (!ret) { ret = btrfs_end_transaction(trans, root); goto out; } } if (!full_sync) { ret = btrfs_wait_ordered_range(inode, start, end - start + 1); if (ret) { btrfs_end_transaction(trans, root); goto out; } } ret = btrfs_commit_transaction(trans, root); } else { ret = btrfs_end_transaction(trans, root); } out: return ret > 0 ? -EIO : ret; } static const struct vm_operations_struct btrfs_file_vm_ops = { .fault = filemap_fault, .map_pages = filemap_map_pages, .page_mkwrite = btrfs_page_mkwrite, .remap_pages = generic_file_remap_pages, }; static int btrfs_file_mmap(struct file *filp, struct vm_area_struct *vma) { struct address_space *mapping = filp->f_mapping; if (!mapping->a_ops->readpage) return -ENOEXEC; file_accessed(filp); vma->vm_ops = &btrfs_file_vm_ops; return 0; } static int hole_mergeable(struct inode *inode, struct extent_buffer *leaf, int slot, u64 start, u64 end) { struct btrfs_file_extent_item *fi; struct btrfs_key key; if (slot < 0 || slot >= btrfs_header_nritems(leaf)) return 0; btrfs_item_key_to_cpu(leaf, &key, slot); if (key.objectid != btrfs_ino(inode) || key.type != BTRFS_EXTENT_DATA_KEY) return 0; fi = btrfs_item_ptr(leaf, slot, struct btrfs_file_extent_item); if (btrfs_file_extent_type(leaf, fi) != BTRFS_FILE_EXTENT_REG) return 0; if (btrfs_file_extent_disk_bytenr(leaf, fi)) return 0; if (key.offset == end) return 1; if (key.offset + btrfs_file_extent_num_bytes(leaf, fi) == start) return 1; return 0; } static int fill_holes(struct btrfs_trans_handle *trans, struct inode *inode, struct btrfs_path *path, u64 offset, u64 end) { struct btrfs_root *root = BTRFS_I(inode)->root; struct extent_buffer *leaf; struct btrfs_file_extent_item *fi; struct extent_map *hole_em; struct extent_map_tree *em_tree = &BTRFS_I(inode)->extent_tree; struct btrfs_key key; int ret; if (btrfs_fs_incompat(root->fs_info, NO_HOLES)) goto out; key.objectid = btrfs_ino(inode); key.type = BTRFS_EXTENT_DATA_KEY; key.offset = offset; ret = btrfs_search_slot(trans, root, &key, path, 0, 1); if (ret < 0) return ret; BUG_ON(!ret); leaf = path->nodes[0]; if (hole_mergeable(inode, leaf, path->slots[0]-1, offset, end)) { u64 num_bytes; path->slots[0]--; fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); num_bytes = btrfs_file_extent_num_bytes(leaf, fi) + end - offset; btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes); btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes); btrfs_set_file_extent_offset(leaf, fi, 0); btrfs_mark_buffer_dirty(leaf); goto out; } if (hole_mergeable(inode, leaf, path->slots[0], offset, end)) { u64 num_bytes; key.offset = offset; btrfs_set_item_key_safe(root, path, &key); fi = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_file_extent_item); num_bytes = btrfs_file_extent_num_bytes(leaf, fi) + end - offset; btrfs_set_file_extent_num_bytes(leaf, fi, num_bytes); btrfs_set_file_extent_ram_bytes(leaf, fi, num_bytes); btrfs_set_file_extent_offset(leaf, fi, 0); btrfs_mark_buffer_dirty(leaf); goto out; } btrfs_release_path(path); ret = btrfs_insert_file_extent(trans, root, btrfs_ino(inode), offset, 0, 0, end - offset, 0, end - offset, 0, 0, 0); if (ret) return ret; out: btrfs_release_path(path); hole_em = alloc_extent_map(); if (!hole_em) { btrfs_drop_extent_cache(inode, offset, end - 1, 0); set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); } else { hole_em->start = offset; hole_em->len = end - offset; hole_em->ram_bytes = hole_em->len; hole_em->orig_start = offset; hole_em->block_start = EXTENT_MAP_HOLE; hole_em->block_len = 0; hole_em->orig_block_len = 0; hole_em->bdev = root->fs_info->fs_devices->latest_bdev; hole_em->compress_type = BTRFS_COMPRESS_NONE; hole_em->generation = trans->transid; do { btrfs_drop_extent_cache(inode, offset, end - 1, 0); write_lock(&em_tree->lock); ret = add_extent_mapping(em_tree, hole_em, 1); write_unlock(&em_tree->lock); } while (ret == -EEXIST); free_extent_map(hole_em); if (ret) set_bit(BTRFS_INODE_NEEDS_FULL_SYNC, &BTRFS_I(inode)->runtime_flags); } return 0; } /* * Find a hole extent on given inode and change start/len to the end of hole * extent.(hole/vacuum extent whose em->start <= start && * em->start + em->len > start) * When a hole extent is found, return 1 and modify start/len. */ static int find_first_non_hole(struct inode *inode, u64 *start, u64 *len) { struct extent_map *em; int ret = 0; em = btrfs_get_extent(inode, NULL, 0, *start, *len, 0); if (IS_ERR_OR_NULL(em)) { if (!em) ret = -ENOMEM; else ret = PTR_ERR(em); return ret; } /* Hole or vacuum extent(only exists in no-hole mode) */ if (em->block_start == EXTENT_MAP_HOLE) { ret = 1; *len = em->start + em->len > *start + *len ? 0 : *start + *len - em->start - em->len; *start = em->start + em->len; } free_extent_map(em); return ret; } static int btrfs_punch_hole(struct inode *inode, loff_t offset, loff_t len) { struct btrfs_root *root = BTRFS_I(inode)->root; struct extent_state *cached_state = NULL; struct btrfs_path *path; struct btrfs_block_rsv *rsv; struct btrfs_trans_handle *trans; u64 lockstart; u64 lockend; u64 tail_start; u64 tail_len; u64 orig_start = offset; u64 cur_offset; u64 min_size = btrfs_calc_trunc_metadata_size(root, 1); u64 drop_end; int ret = 0; int err = 0; int rsv_count; bool same_page; bool no_holes = btrfs_fs_incompat(root->fs_info, NO_HOLES); u64 ino_size; ret = btrfs_wait_ordered_range(inode, offset, len); if (ret) return ret; mutex_lock(&inode->i_mutex); ino_size = round_up(inode->i_size, PAGE_CACHE_SIZE); ret = find_first_non_hole(inode, &offset, &len); if (ret < 0) goto out_only_mutex; if (ret && !len) { /* Already in a large hole */ ret = 0; goto out_only_mutex; } lockstart = round_up(offset, BTRFS_I(inode)->root->sectorsize); lockend = round_down(offset + len, BTRFS_I(inode)->root->sectorsize) - 1; same_page = ((offset >> PAGE_CACHE_SHIFT) == ((offset + len - 1) >> PAGE_CACHE_SHIFT)); /* * We needn't truncate any page which is beyond the end of the file * because we are sure there is no data there. */ /* * Only do this if we are in the same page and we aren't doing the * entire page. */ if (same_page && len < PAGE_CACHE_SIZE) { if (offset < ino_size) ret = btrfs_truncate_page(inode, offset, len, 0); goto out_only_mutex; } /* zero back part of the first page */ if (offset < ino_size) { ret = btrfs_truncate_page(inode, offset, 0, 0); if (ret) { mutex_unlock(&inode->i_mutex); return ret; } } /* Check the aligned pages after the first unaligned page, * if offset != orig_start, which means the first unaligned page * including serveral following pages are already in holes, * the extra check can be skipped */ if (offset == orig_start) { /* after truncate page, check hole again */ len = offset + len - lockstart; offset = lockstart; ret = find_first_non_hole(inode, &offset, &len); if (ret < 0) goto out_only_mutex; if (ret && !len) { ret = 0; goto out_only_mutex; } lockstart = offset; } /* Check the tail unaligned part is in a hole */ tail_start = lockend + 1; tail_len = offset + len - tail_start; if (tail_len) { ret = find_first_non_hole(inode, &tail_start, &tail_len); if (unlikely(ret < 0)) goto out_only_mutex; if (!ret) { /* zero the front end of the last page */ if (tail_start + tail_len < ino_size) { ret = btrfs_truncate_page(inode, tail_start + tail_len, 0, 1); if (ret) goto out_only_mutex; } } } if (lockend < lockstart) { mutex_unlock(&inode->i_mutex); return 0; } while (1) { struct btrfs_ordered_extent *ordered; truncate_pagecache_range(inode, lockstart, lockend); lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend, 0, &cached_state); ordered = btrfs_lookup_first_ordered_extent(inode, lockend); /* * We need to make sure we have no ordered extents in this range * and nobody raced in and read a page in this range, if we did * we need to try again. */ if ((!ordered || (ordered->file_offset + ordered->len <= lockstart || ordered->file_offset > lockend)) && !btrfs_page_exists_in_range(inode, lockstart, lockend)) { if (ordered) btrfs_put_ordered_extent(ordered); break; } if (ordered) btrfs_put_ordered_extent(ordered); unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend, &cached_state, GFP_NOFS); ret = btrfs_wait_ordered_range(inode, lockstart, lockend - lockstart + 1); if (ret) { mutex_unlock(&inode->i_mutex); return ret; } } path = btrfs_alloc_path(); if (!path) { ret = -ENOMEM; goto out; } rsv = btrfs_alloc_block_rsv(root, BTRFS_BLOCK_RSV_TEMP); if (!rsv) { ret = -ENOMEM; goto out_free; } rsv->size = btrfs_calc_trunc_metadata_size(root, 1); rsv->failfast = 1; /* * 1 - update the inode * 1 - removing the extents in the range * 1 - adding the hole extent if no_holes isn't set */ rsv_count = no_holes ? 2 : 3; trans = btrfs_start_transaction(root, rsv_count); if (IS_ERR(trans)) { err = PTR_ERR(trans); goto out_free; } ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, rsv, min_size); BUG_ON(ret); trans->block_rsv = rsv; cur_offset = lockstart; len = lockend - cur_offset; while (cur_offset < lockend) { ret = __btrfs_drop_extents(trans, root, inode, path, cur_offset, lockend + 1, &drop_end, 1, 0, 0, NULL); if (ret != -ENOSPC) break; trans->block_rsv = &root->fs_info->trans_block_rsv; if (cur_offset < ino_size) { ret = fill_holes(trans, inode, path, cur_offset, drop_end); if (ret) { err = ret; break; } } cur_offset = drop_end; ret = btrfs_update_inode(trans, root, inode); if (ret) { err = ret; break; } btrfs_end_transaction(trans, root); btrfs_btree_balance_dirty(root); trans = btrfs_start_transaction(root, rsv_count); if (IS_ERR(trans)) { ret = PTR_ERR(trans); trans = NULL; break; } ret = btrfs_block_rsv_migrate(&root->fs_info->trans_block_rsv, rsv, min_size); BUG_ON(ret); /* shouldn't happen */ trans->block_rsv = rsv; ret = find_first_non_hole(inode, &cur_offset, &len); if (unlikely(ret < 0)) break; if (ret && !len) { ret = 0; break; } } if (ret) { err = ret; goto out_trans; } trans->block_rsv = &root->fs_info->trans_block_rsv; /* * Don't insert file hole extent item if it's for a range beyond eof * (because it's useless) or if it represents a 0 bytes range (when * cur_offset == drop_end). */ if (cur_offset < ino_size && cur_offset < drop_end) { ret = fill_holes(trans, inode, path, cur_offset, drop_end); if (ret) { err = ret; goto out_trans; } } out_trans: if (!trans) goto out_free; inode_inc_iversion(inode); inode->i_mtime = inode->i_ctime = CURRENT_TIME; trans->block_rsv = &root->fs_info->trans_block_rsv; ret = btrfs_update_inode(trans, root, inode); btrfs_end_transaction(trans, root); btrfs_btree_balance_dirty(root); out_free: btrfs_free_path(path); btrfs_free_block_rsv(root, rsv); out: unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend, &cached_state, GFP_NOFS); out_only_mutex: mutex_unlock(&inode->i_mutex); if (ret && !err) err = ret; return err; } static long btrfs_fallocate(struct file *file, int mode, loff_t offset, loff_t len) { struct inode *inode = file_inode(file); struct extent_state *cached_state = NULL; struct btrfs_root *root = BTRFS_I(inode)->root; u64 cur_offset; u64 last_byte; u64 alloc_start; u64 alloc_end; u64 alloc_hint = 0; u64 locked_end; struct extent_map *em; int blocksize = BTRFS_I(inode)->root->sectorsize; int ret; alloc_start = round_down(offset, blocksize); alloc_end = round_up(offset + len, blocksize); /* Make sure we aren't being give some crap mode */ if (mode & ~(FALLOC_FL_KEEP_SIZE | FALLOC_FL_PUNCH_HOLE)) return -EOPNOTSUPP; if (mode & FALLOC_FL_PUNCH_HOLE) return btrfs_punch_hole(inode, offset, len); /* * Make sure we have enough space before we do the * allocation. */ ret = btrfs_check_data_free_space(inode, alloc_end - alloc_start); if (ret) return ret; if (root->fs_info->quota_enabled) { ret = btrfs_qgroup_reserve(root, alloc_end - alloc_start); if (ret) goto out_reserve_fail; } mutex_lock(&inode->i_mutex); ret = inode_newsize_ok(inode, alloc_end); if (ret) goto out; if (alloc_start > inode->i_size) { ret = btrfs_cont_expand(inode, i_size_read(inode), alloc_start); if (ret) goto out; } else { /* * If we are fallocating from the end of the file onward we * need to zero out the end of the page if i_size lands in the * middle of a page. */ ret = btrfs_truncate_page(inode, inode->i_size, 0, 0); if (ret) goto out; } /* * wait for ordered IO before we have any locks. We'll loop again * below with the locks held. */ ret = btrfs_wait_ordered_range(inode, alloc_start, alloc_end - alloc_start); if (ret) goto out; locked_end = alloc_end - 1; while (1) { struct btrfs_ordered_extent *ordered; /* the extent lock is ordered inside the running * transaction */ lock_extent_bits(&BTRFS_I(inode)->io_tree, alloc_start, locked_end, 0, &cached_state); ordered = btrfs_lookup_first_ordered_extent(inode, alloc_end - 1); if (ordered && ordered->file_offset + ordered->len > alloc_start && ordered->file_offset < alloc_end) { btrfs_put_ordered_extent(ordered); unlock_extent_cached(&BTRFS_I(inode)->io_tree, alloc_start, locked_end, &cached_state, GFP_NOFS); /* * we can't wait on the range with the transaction * running or with the extent lock held */ ret = btrfs_wait_ordered_range(inode, alloc_start, alloc_end - alloc_start); if (ret) goto out; } else { if (ordered) btrfs_put_ordered_extent(ordered); break; } } cur_offset = alloc_start; while (1) { u64 actual_end; em = btrfs_get_extent(inode, NULL, 0, cur_offset, alloc_end - cur_offset, 0); if (IS_ERR_OR_NULL(em)) { if (!em) ret = -ENOMEM; else ret = PTR_ERR(em); break; } last_byte = min(extent_map_end(em), alloc_end); actual_end = min_t(u64, extent_map_end(em), offset + len); last_byte = ALIGN(last_byte, blocksize); if (em->block_start == EXTENT_MAP_HOLE || (cur_offset >= inode->i_size && !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) { ret = btrfs_prealloc_file_range(inode, mode, cur_offset, last_byte - cur_offset, 1 << inode->i_blkbits, offset + len, &alloc_hint); if (ret < 0) { free_extent_map(em); break; } } else if (actual_end > inode->i_size && !(mode & FALLOC_FL_KEEP_SIZE)) { /* * We didn't need to allocate any more space, but we * still extended the size of the file so we need to * update i_size. */ inode->i_ctime = CURRENT_TIME; i_size_write(inode, actual_end); btrfs_ordered_update_i_size(inode, actual_end, NULL); } free_extent_map(em); cur_offset = last_byte; if (cur_offset >= alloc_end) { ret = 0; break; } } unlock_extent_cached(&BTRFS_I(inode)->io_tree, alloc_start, locked_end, &cached_state, GFP_NOFS); out: mutex_unlock(&inode->i_mutex); if (root->fs_info->quota_enabled) btrfs_qgroup_free(root, alloc_end - alloc_start); out_reserve_fail: /* Let go of our reservation. */ btrfs_free_reserved_data_space(inode, alloc_end - alloc_start); return ret; } static int find_desired_extent(struct inode *inode, loff_t *offset, int whence) { struct btrfs_root *root = BTRFS_I(inode)->root; struct extent_map *em = NULL; struct extent_state *cached_state = NULL; u64 lockstart = *offset; u64 lockend = i_size_read(inode); u64 start = *offset; u64 len = i_size_read(inode); int ret = 0; lockend = max_t(u64, root->sectorsize, lockend); if (lockend <= lockstart) lockend = lockstart + root->sectorsize; lockend--; len = lockend - lockstart + 1; len = max_t(u64, len, root->sectorsize); if (inode->i_size == 0) return -ENXIO; lock_extent_bits(&BTRFS_I(inode)->io_tree, lockstart, lockend, 0, &cached_state); while (start < inode->i_size) { em = btrfs_get_extent_fiemap(inode, NULL, 0, start, len, 0); if (IS_ERR(em)) { ret = PTR_ERR(em); em = NULL; break; } if (whence == SEEK_HOLE && (em->block_start == EXTENT_MAP_HOLE || test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) break; else if (whence == SEEK_DATA && (em->block_start != EXTENT_MAP_HOLE && !test_bit(EXTENT_FLAG_PREALLOC, &em->flags))) break; start = em->start + em->len; free_extent_map(em); em = NULL; cond_resched(); } free_extent_map(em); if (!ret) { if (whence == SEEK_DATA && start >= inode->i_size) ret = -ENXIO; else *offset = min_t(loff_t, start, inode->i_size); } unlock_extent_cached(&BTRFS_I(inode)->io_tree, lockstart, lockend, &cached_state, GFP_NOFS); return ret; } static loff_t btrfs_file_llseek(struct file *file, loff_t offset, int whence) { struct inode *inode = file->f_mapping->host; int ret; mutex_lock(&inode->i_mutex); switch (whence) { case SEEK_END: case SEEK_CUR: offset = generic_file_llseek(file, offset, whence); goto out; case SEEK_DATA: case SEEK_HOLE: if (offset >= i_size_read(inode)) { mutex_unlock(&inode->i_mutex); return -ENXIO; } ret = find_desired_extent(inode, &offset, whence); if (ret) { mutex_unlock(&inode->i_mutex); return ret; } } offset = vfs_setpos(file, offset, inode->i_sb->s_maxbytes); out: mutex_unlock(&inode->i_mutex); return offset; } const struct file_operations btrfs_file_operations = { .llseek = btrfs_file_llseek, .read = new_sync_read, .write = new_sync_write, .read_iter = generic_file_read_iter, .splice_read = generic_file_splice_read, .write_iter = btrfs_file_write_iter, .mmap = btrfs_file_mmap, .open = generic_file_open, .release = btrfs_release_file, .fsync = btrfs_sync_file, .fallocate = btrfs_fallocate, .unlocked_ioctl = btrfs_ioctl, #ifdef CONFIG_COMPAT .compat_ioctl = btrfs_ioctl, #endif }; void btrfs_auto_defrag_exit(void) { if (btrfs_inode_defrag_cachep) kmem_cache_destroy(btrfs_inode_defrag_cachep); } int btrfs_auto_defrag_init(void) { btrfs_inode_defrag_cachep = kmem_cache_create("btrfs_inode_defrag", sizeof(struct inode_defrag), 0, SLAB_RECLAIM_ACCOUNT | SLAB_MEM_SPREAD, NULL); if (!btrfs_inode_defrag_cachep) return -ENOMEM; return 0; }