From 1e72c0f7c40e665d2ed40014750fdd2fa9968bcf Mon Sep 17 00:00:00 2001 From: Steven Whitehouse Date: Tue, 15 Sep 2009 20:42:56 +0100 Subject: GFS2: Clean up gfs2_adjust_quota() and do_glock() Both of these functions contained confusing and in one case duplicate code. This patch adds a new check in do_glock() so that we report -ENOENT if we are asked to sync a quota entry which doesn't exist. Due to the previous patch this is now reported correctly to userspace. Also there are a few new comments, and I hope that the code is easier to understand now. Signed-off-by: Steven Whitehouse --- fs/gfs2/quota.c | 82 ++++++++++++++++++--------------------------------------- 1 file changed, 26 insertions(+), 56 deletions(-) (limited to 'fs') diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c index db124af8998e..33e369f108b3 100644 --- a/fs/gfs2/quota.c +++ b/fs/gfs2/quota.c @@ -15,7 +15,7 @@ * fuzziness in the current usage value of IDs that are being used on different * nodes in the cluster simultaneously. So, it is possible for a user on * multiple nodes to overrun their quota, but that overrun is controlable. - * Since quota tags are part of transactions, there is no need to a quota check + * Since quota tags are part of transactions, there is no need for a quota check * program to be run on node crashes or anything like that. * * There are couple of knobs that let the administrator manage the quota @@ -66,13 +66,6 @@ #define QUOTA_USER 1 #define QUOTA_GROUP 0 -struct gfs2_quota_host { - u64 qu_limit; - u64 qu_warn; - s64 qu_value; - u32 qu_ll_next; -}; - struct gfs2_quota_change_host { u64 qc_change; u32 qc_flags; /* GFS2_QCF_... */ @@ -618,33 +611,19 @@ static void do_qc(struct gfs2_quota_data *qd, s64 change) mutex_unlock(&sdp->sd_quota_mutex); } -static void gfs2_quota_in(struct gfs2_quota_host *qu, const void *buf) -{ - const struct gfs2_quota *str = buf; - - qu->qu_limit = be64_to_cpu(str->qu_limit); - qu->qu_warn = be64_to_cpu(str->qu_warn); - qu->qu_value = be64_to_cpu(str->qu_value); - qu->qu_ll_next = be32_to_cpu(str->qu_ll_next); -} - -static void gfs2_quota_out(const struct gfs2_quota_host *qu, void *buf) -{ - struct gfs2_quota *str = buf; - - str->qu_limit = cpu_to_be64(qu->qu_limit); - str->qu_warn = cpu_to_be64(qu->qu_warn); - str->qu_value = cpu_to_be64(qu->qu_value); - str->qu_ll_next = cpu_to_be32(qu->qu_ll_next); - memset(&str->qu_reserved, 0, sizeof(str->qu_reserved)); -} - /** - * gfs2_adjust_quota + * gfs2_adjust_quota - adjust record of current block usage + * @ip: The quota inode + * @loc: Offset of the entry in the quota file + * @change: The amount of change to record + * @qd: The quota data * * This function was mostly borrowed from gfs2_block_truncate_page which was * in turn mostly borrowed from ext3 + * + * Returns: 0 or -ve on error */ + static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc, s64 change, struct gfs2_quota_data *qd) { @@ -656,8 +635,7 @@ static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc, struct buffer_head *bh; struct page *page; void *kaddr; - char *ptr; - struct gfs2_quota_host qp; + struct gfs2_quota *qp; s64 value; int err = -EIO; @@ -701,18 +679,13 @@ static int gfs2_adjust_quota(struct gfs2_inode *ip, loff_t loc, gfs2_trans_add_bh(ip->i_gl, bh, 0); kaddr = kmap_atomic(page, KM_USER0); - ptr = kaddr + offset; - gfs2_quota_in(&qp, ptr); - qp.qu_value += change; - value = qp.qu_value; - gfs2_quota_out(&qp, ptr); + qp = kaddr + offset; + value = (s64)be64_to_cpu(qp->qu_value) + change; + qp->qu_value = cpu_to_be64(value); + qd->qd_qb.qb_value = qp->qu_value; flush_dcache_page(page); kunmap_atomic(kaddr, KM_USER0); err = 0; - qd->qd_qb.qb_magic = cpu_to_be32(GFS2_MAGIC); - qd->qd_qb.qb_value = cpu_to_be64(value); - ((struct gfs2_quota_lvb*)(qd->qd_gl->gl_lvb))->qb_magic = cpu_to_be32(GFS2_MAGIC); - ((struct gfs2_quota_lvb*)(qd->qd_gl->gl_lvb))->qb_value = cpu_to_be64(value); unlock: unlock_page(page); page_cache_release(page); @@ -741,8 +714,7 @@ static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda) sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL); for (qx = 0; qx < num_qd; qx++) { - error = gfs2_glock_nq_init(qda[qx]->qd_gl, - LM_ST_EXCLUSIVE, + error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE, GL_NOCACHE, &ghs[qx]); if (error) goto out; @@ -797,8 +769,7 @@ static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda) qd = qda[x]; offset = qd2offset(qd); error = gfs2_adjust_quota(ip, offset, qd->qd_change_sync, - (struct gfs2_quota_data *) - qd); + (struct gfs2_quota_data *)qd); if (error) goto out_end_trans; @@ -829,8 +800,7 @@ static int do_glock(struct gfs2_quota_data *qd, int force_refresh, struct gfs2_sbd *sdp = qd->qd_gl->gl_sbd; struct gfs2_inode *ip = GFS2_I(sdp->sd_quota_inode); struct gfs2_holder i_gh; - struct gfs2_quota_host q; - char buf[sizeof(struct gfs2_quota)]; + struct gfs2_quota q; int error; struct gfs2_quota_lvb *qlvb; @@ -853,22 +823,23 @@ restart: if (error) goto fail; - memset(buf, 0, sizeof(struct gfs2_quota)); + memset(&q, 0, sizeof(struct gfs2_quota)); pos = qd2offset(qd); - error = gfs2_internal_read(ip, NULL, buf, &pos, - sizeof(struct gfs2_quota)); + error = gfs2_internal_read(ip, NULL, (char *)&q, &pos, sizeof(q)); if (error < 0) goto fail_gunlock; - + if ((error < sizeof(q)) && force_refresh) { + error = -ENOENT; + goto fail_gunlock; + } gfs2_glock_dq_uninit(&i_gh); - gfs2_quota_in(&q, buf); qlvb = (struct gfs2_quota_lvb *)qd->qd_gl->gl_lvb; qlvb->qb_magic = cpu_to_be32(GFS2_MAGIC); qlvb->__pad = 0; - qlvb->qb_limit = cpu_to_be64(q.qu_limit); - qlvb->qb_warn = cpu_to_be64(q.qu_warn); - qlvb->qb_value = cpu_to_be64(q.qu_value); + qlvb->qb_limit = q.qu_limit; + qlvb->qb_warn = q.qu_warn; + qlvb->qb_value = q.qu_value; qd->qd_qb = *qlvb; gfs2_glock_dq_uninit(q_gh); @@ -1126,7 +1097,6 @@ int gfs2_quota_refresh(struct gfs2_sbd *sdp, int user, u32 id) gfs2_glock_dq_uninit(&q_gh); qd_put(qd); - return error; } -- cgit v1.2.3-59-g8ed1b