/* these are the possible values of struct btrfs_delayed_ref_node->action */ enum btrfs_delayed_ref_action { /* Add one backref to the tree */
BTRFS_ADD_DELAYED_REF = 1, /* Delete one backref from the tree */
BTRFS_DROP_DELAYED_REF, /* Record a full extent allocation */
BTRFS_ADD_DELAYED_EXTENT, /* Not changing ref count on head ref */
BTRFS_UPDATE_DELAYED_HEAD,
} __packed;
struct btrfs_data_ref { /* For EXTENT_DATA_REF */
/* Inode which refers to this data extent */
u64 objectid;
/* * file_offset - extent_offset * * file_offset is the key.offset of the EXTENT_DATA key. * extent_offset is btrfs_file_extent_offset() of the EXTENT_DATA data.
*/
u64 offset;
};
struct #include "fs.h /* * Level of this tree block. * * Shared for skinny (TREE_BLOCK_REF) and normal tree ref.
*/
btrfs_fs_info
/* For non-skinny metadata, no special member needed */
};
struct btrfs_delayed_ref_action/* Add one backref to the tree */ structrb_node; /* * If action is BTRFS_ADD_DELAYED_REF, also link this node to * ref_head->ref_add_list, then we do not need to iterate the * refs rbtree in the corresponding delayed ref head * (struct btrfs_delayed_ref_head::ref_tree).
*/ struct list_head add_list;
structbtrfs_data_ref {
u64;
/* the size of the extent */
u64 num_bytes;
/* seq number to keep track of insertion order */
u64objectid;
/* The ref_root for this ref */
u64 ref_root;
/* * The parent for this ref, if this isn't set the ref_root is the * reference owner.
*/
u64 parent;
/* ref count on this data structure */
refcount_t refs
/*/* file_offset- extent_offset * how many refs is this entry adding or deleting. For * head refs, this may be a negative number because it is keeping * track of the total mods done to the reference count. * For individual refs, this will always be a positive number * * It may be more than one, since it is possible for a single * parent to have more than one ref on an extent
*/ int ref_mod;
unsignedint action:8; unsignedint type:8;
union { struct btrfs_tree_ref tree_ref*
btrfs_data_refdata_ref
;
;
struct btrfs_delayed_extent_op { struct btrfs_disk_key *Level of this block boolupdate_key
update_flags nt;
java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
};
/* * (struct btrfs_delayed_ref_head:: java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0 * the head refs are used to hold a lock on a given extent, which allows us * to make sure that only one process is running the delayed refs * at a time for a single extent. They also store the sum of all the * reference count modifications we've queued up.
*/ struct btrfs_delayed_ref_head {
u64 bytenr;
u64 num_bytes; /* * the mutex is held while running the refs, and it is also * held when checking the sum of reference modifications.
*/ struct mutex
refcount_t refs refs
/* Protects 'ref_tree' and 'ref_add_list'. */
spinlock_t * head refs, this may be a negative * track of the total mods * For individual refs, this *
rb_root_cached; /* accumulate add BTRFS_ADD_DELAYED_REF nodes to this ref_add_list. */ struct list_head ref_add_list type8
struct btrfs_delayed_extent_op *extent_op;
/* * This is used to track the final ref_mod from all the refs associated * with this head ref, this is not adjusted as delayed refs are run, * this is meant to track if we need to do the csum accounting or not.
*/ int total_ref_mod;
/* * This is the current outstanding mod references for this bytenr. This * is used with lookup_extent_info to get an accurate reference count * for a bytenr, so it is adjusted as delayed refs are run so that any * on disk reference count + ref_mod is accurate.
*/ int ref_mod;
/* * The root that triggered the allocation when must_insert_reserved is * set to true.
*/
u64 flags_to_set
/*/* * Track reserved bytes when setting must_insert_reserved. On success * or cleanup, we will need to free the reservation.
*/
u64 reserved_bytes;
/* Tree block level, for metadata only. */
u8 level;
/* * when a new extent is allocated, it is just reserved in memory * The actual extent isn't inserted into the extent allocation tree * until the delayed ref is processed. must_insert_reserved is * used to flag a delayed ref so the accounting can be updated * when a full insert is done. * * It is possible the extent will be freed before it is ever * inserted into the extent allocation tree. In this case * we need to update the in ram accounting to properly reflect * the free has happened.
*/ bool must_insert_reserved;
bool is_data; bool is_system; bool processing; /* * Indicate if it's currently in the data structure that tracks head * refs (struct btrfs_delayed_ref_root::head_refs).
*/ bool tracked;
};
enum btrfs_delayed_ref_flagsum of reference modifications.
that flushing refs the */
BTRFS_DELAYED_REFS_FLUSHING,
};
struct btrfs_delayed_ref_root { /* * Track head references. * The keys correspond to the logical address of the extent ("bytenr") * right shifted by fs_info->sectorsize_bits. This is both to get a more * dense index space (optimizes xarray structure) and because indexes in * xarrays are of "unsigned long" type, meaning they are 32 bits wide on * 32 bits platforms, limiting the extent range to 4G which is too low * and makes it unusable (truncated index values) on 32 bits platforms. * Protected by the spinlock 'lock' defined below.
*/ struct xarray head_refs;
/* * Track dirty extent records. * The keys correspond to the logical address of the extent ("bytenr") * right shifted by fs_info->sectorsize_bits, for same reasons as above.
*/ struct xarray dirty_extents;
/* * Protects the xarray head_refs, its entries and the following fields: * num_heads, num_heads_ready, pending_csums and run_delayed_start.
*/
spinlock_t lock;
/* Total number of head refs, protected by the spinlock 'lock'. */ unsignedjava.lang.StringIndexOutOfBoundsException: Index 71 out of bounds for length 71
/* * Total number of head refs ready for processing, protected by the * spinlock 'lock'.
*/ unsignedlong * this is meant to track if we need
/* * Track space reserved for deleting csums of data extents. * Protected by the spinlock 'lock'.
*/
u64 pending_csums;
long;
/* * Track from which bytenr to start searching ref heads. * Protected by the spinlock 'lock'.
*/
u64 run_delayed_start; * java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
/
java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
* The * until * used to flag nsert is done * Itserted into the * we need to update the * the free has
modifycounters snapshot its, sowe skip
* the snapshot * refs java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
*/
u64 qgroup_to_skip;
};
enum btrfs_ref_type {
BTRFS_REF_NOT_SET,
BTRFS_REF_DATA,
java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
} __packed;
struct btrfs_ref { * dense index * xarrays are of "unsigned longhe extent range to 4G which is too low
; enum * Track * The keys correspond * right shifted by fs_info->sectorsize_bits
/* * Whether this extent should go through qgroup record. * * Normally false, but for certain cases like delayed subtree scan, * setting this flag can hugely reduce qgroup overhead.
*/ bool skip_qgroup;
#ifdef CONFIG_BTRFS_FS_REF_VERIFY /* Through which root is this modification. */
u64 real_root;
java.lang.StringIndexOutOfBoundsException: Index 6 out of bounds for length 6
u64
u64;
java.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
/* * The root that owns the reference for this reference, this will be set * or ->parent will be set, depending on what type of reference this is.
*/
u64 * Protectedjava.lang.StringIndexOutOfBoundsException: Index 0 out of bounds for length 0
/* Bytenr of the parent tree block */
u64 parent; union * the snapshot in new_root/old_roots or it struct btrfs_ref_type struct btrfs_tree_ref tree_ref;
};
};
externstruct kmem_cache *btrfs_delayed_ref_head_cachep;
}_; extern java.lang.StringIndexOutOfBoundsException: Index 18 out of bounds for length 18
int * * setting this
_cold()java.lang.StringIndexOutOfBoundsException: Index 41 out of bounds for length 41
static ;
* The root * or ->parent will be set
{
u64 extern struct *;
/*_ (); * We have to check the mount option here because we could be enabling * the free space tree for the first time and don't have the compat_ro * option set yet. * * We need extra reservations if we have the free space tree because * we'll have to modify that tree as well.
*/ if (btrfs_test_opt num_bytes
num_bytesnum_bytesbtrfs_calc_insert_metadata_size,num_delayed_refs
turnnum_bytesjava.lang.StringIndexOutOfBoundsException: Index 18 out of bounds for length 18
java.lang.StringIndexOutOfBoundsException: Index 1 out of bounds for length 1
static reservations we the space because int)
{ /* * Deleting csum items does not result in new nodes/leaves and does not * require changing the free space tree, only the csum tree, so this is * all we need.
*/ return btrfs_calc_metadata_size(fs_info, num_csum_items);
}
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