#include "xfs_metafile.h"
#include "xfs_trace.h"
#include "xfs_inode.h"
+#include "xfs_errortag.h"
+#include "xfs_alloc.h"
/* Set up an inode to be recognized as a metadata directory inode. */
void
ip->i_diflags2 &= ~XFS_DIFLAG2_METADATA;
xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
}
+
+/*
+ * Is the amount of space that could be allocated towards a given metadata
+ * file at or beneath a certain threshold?
+ */
+static inline bool
+xfs_metafile_resv_can_cover(
+ struct xfs_inode *ip,
+ int64_t rhs)
+{
+ /*
+ * The amount of space that can be allocated to this metadata file is
+ * the remaining reservation for the particular metadata file + the
+ * global free block count. Take care of the first case to avoid
+ * touching the per-cpu counter.
+ */
+ if (ip->i_delayed_blks >= rhs)
+ return true;
+
+ /*
+ * There aren't enough blocks left in the inode's reservation, but it
+ * isn't critical unless there also isn't enough free space.
+ */
+ return __percpu_counter_compare(&ip->i_mount->m_fdblocks,
+ rhs - ip->i_delayed_blks, 2048) >= 0;
+}
+
+/*
+ * Is this metadata file critically low on blocks? For now we'll define that
+ * as the number of blocks we can get our hands on being less than 10% of what
+ * we reserved or less than some arbitrary number (maximum btree height).
+ */
+bool
+xfs_metafile_resv_critical(
+ struct xfs_inode *ip)
+{
+ uint64_t asked_low_water;
+
+ if (!ip)
+ return false;
+
+ ASSERT(xfs_is_metadir_inode(ip));
+ trace_xfs_metafile_resv_critical(ip, 0);
+
+ if (!xfs_metafile_resv_can_cover(ip, ip->i_mount->m_rtbtree_maxlevels))
+ return true;
+
+ asked_low_water = div_u64(ip->i_meta_resv_asked, 10);
+ if (!xfs_metafile_resv_can_cover(ip, asked_low_water))
+ return true;
+
+ return XFS_TEST_ERROR(false, ip->i_mount,
+ XFS_ERRTAG_METAFILE_RESV_CRITICAL);
+}
+
+/* Allocate a block from the metadata file's reservation. */
+void
+xfs_metafile_resv_alloc_space(
+ struct xfs_inode *ip,
+ struct xfs_alloc_arg *args)
+{
+ int64_t len = args->len;
+
+ ASSERT(xfs_is_metadir_inode(ip));
+ ASSERT(args->resv == XFS_AG_RESV_METAFILE);
+
+ trace_xfs_metafile_resv_alloc_space(ip, args->len);
+
+ /*
+ * Allocate the blocks from the metadata inode's block reservation
+ * and update the ondisk sb counter.
+ */
+ if (ip->i_delayed_blks > 0) {
+ int64_t from_resv;
+
+ from_resv = min_t(int64_t, len, ip->i_delayed_blks);
+ ip->i_delayed_blks -= from_resv;
+ xfs_mod_delalloc(ip, 0, -from_resv);
+ xfs_trans_mod_sb(args->tp, XFS_TRANS_SB_RES_FDBLOCKS,
+ -from_resv);
+ len -= from_resv;
+ }
+
+ /*
+ * Any allocation in excess of the reservation requires in-core and
+ * on-disk fdblocks updates. If we can grab @len blocks from the
+ * in-core fdblocks then all we need to do is update the on-disk
+ * superblock; if not, then try to steal some from the transaction's
+ * block reservation. Overruns are only expected for rmap btrees.
+ */
+ if (len) {
+ unsigned int field;
+ int error;
+
+ error = xfs_dec_fdblocks(ip->i_mount, len, true);
+ if (error)
+ field = XFS_TRANS_SB_FDBLOCKS;
+ else
+ field = XFS_TRANS_SB_RES_FDBLOCKS;
+
+ xfs_trans_mod_sb(args->tp, field, -len);
+ }
+
+ ip->i_nblocks += args->len;
+ xfs_trans_log_inode(args->tp, ip, XFS_ILOG_CORE);
+}
+
+/* Free a block to the metadata file's reservation. */
+void
+xfs_metafile_resv_free_space(
+ struct xfs_inode *ip,
+ struct xfs_trans *tp,
+ xfs_filblks_t len)
+{
+ int64_t to_resv;
+
+ ASSERT(xfs_is_metadir_inode(ip));
+ trace_xfs_metafile_resv_free_space(ip, len);
+
+ ip->i_nblocks -= len;
+ xfs_trans_log_inode(tp, ip, XFS_ILOG_CORE);
+
+ /*
+ * Add the freed blocks back into the inode's delalloc reservation
+ * until it reaches the maximum size. Update the ondisk fdblocks only.
+ */
+ to_resv = ip->i_meta_resv_asked - (ip->i_nblocks + ip->i_delayed_blks);
+ if (to_resv > 0) {
+ to_resv = min_t(int64_t, to_resv, len);
+ ip->i_delayed_blks += to_resv;
+ xfs_mod_delalloc(ip, 0, to_resv);
+ xfs_trans_mod_sb(tp, XFS_TRANS_SB_RES_FDBLOCKS, to_resv);
+ len -= to_resv;
+ }
+
+ /*
+ * Everything else goes back to the filesystem, so update the in-core
+ * and on-disk counters.
+ */
+ if (len)
+ xfs_trans_mod_sb(tp, XFS_TRANS_SB_FDBLOCKS, len);
+}
+
+/* Release a metadata file's space reservation. */
+void
+xfs_metafile_resv_free(
+ struct xfs_inode *ip)
+{
+ /* Non-btree metadata inodes don't need space reservations. */
+ if (!ip || !ip->i_meta_resv_asked)
+ return;
+
+ ASSERT(xfs_is_metadir_inode(ip));
+ trace_xfs_metafile_resv_free(ip, 0);
+
+ if (ip->i_delayed_blks) {
+ xfs_mod_delalloc(ip, 0, -ip->i_delayed_blks);
+ xfs_add_fdblocks(ip->i_mount, ip->i_delayed_blks);
+ ip->i_delayed_blks = 0;
+ }
+ ip->i_meta_resv_asked = 0;
+}
+
+/* Set up a metadata file's space reservation. */
+int
+xfs_metafile_resv_init(
+ struct xfs_inode *ip,
+ xfs_filblks_t ask)
+{
+ xfs_filblks_t hidden_space;
+ xfs_filblks_t used;
+ int error;
+
+ if (!ip || ip->i_meta_resv_asked > 0)
+ return 0;
+
+ ASSERT(xfs_is_metadir_inode(ip));
+
+ /*
+ * Space taken by all other metadata btrees are accounted on-disk as
+ * used space. We therefore only hide the space that is reserved but
+ * not used by the trees.
+ */
+ used = ip->i_nblocks;
+ if (used > ask)
+ ask = used;
+ hidden_space = ask - used;
+
+ error = xfs_dec_fdblocks(ip->i_mount, hidden_space, true);
+ if (error) {
+ trace_xfs_metafile_resv_init_error(ip, error, _RET_IP_);
+ return error;
+ }
+
+ xfs_mod_delalloc(ip, 0, hidden_space);
+ ip->i_delayed_blks = hidden_space;
+ ip->i_meta_resv_asked = ask;
+
+ trace_xfs_metafile_resv_init(ip, ask);
+ return 0;
+}
projects / thirdparty / xfsprogs-dev.git / commitdiff
