From 755d66b48fe5a1f2a07802fcc8704e8b9e775e7d Mon Sep 17 00:00:00 2001 From: Anton Vorontsov Date: Sat, 26 May 2012 06:20:22 -0700 Subject: [PATCH] pstore/ram: Factor ramoops_get_next_prz() out of ramoops_pstore_read() This will help make code clearer when we'll add support for other message types. The patch also changes return value from -EINVAL to 0 in case of end-of-records. The exact value doesn't matter for pstore (it should be just <= 0), but 0 feels more correct. Signed-off-by: Anton Vorontsov Acked-by: Kees Cook Signed-off-by: Greg Kroah-Hartman --- fs/pstore/ram.c | 41 ++++++++++++++++++++++++++++++++--------- 1 file changed, 32 insertions(+), 9 deletions(-) diff --git a/fs/pstore/ram.c b/fs/pstore/ram.c index 6b7676738493..d770d7266e96 100644 --- a/fs/pstore/ram.c +++ b/fs/pstore/ram.c @@ -85,6 +85,33 @@ static int ramoops_pstore_open(struct pstore_info *psi) return 0; } +static struct persistent_ram_zone * +ramoops_get_next_prz(struct persistent_ram_zone *przs[], uint *c, uint max, + u64 *id, + enum pstore_type_id *typep, enum pstore_type_id type, + bool update) +{ + struct persistent_ram_zone *prz; + int i = (*c)++; + + if (i >= max) + return NULL; + + prz = przs[i]; + + if (update) { + /* Update old/shadowed buffer. */ + persistent_ram_save_old(prz); + if (!persistent_ram_old_size(prz)) + return NULL; + } + + *typep = type; + *id = i; + + return prz; +} + static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type, struct timespec *time, char **buf, @@ -94,20 +121,16 @@ static ssize_t ramoops_pstore_read(u64 *id, enum pstore_type_id *type, struct ramoops_context *cxt = psi->data; struct persistent_ram_zone *prz; - if (cxt->dump_read_cnt >= cxt->max_dump_cnt) - return -EINVAL; - - *id = cxt->dump_read_cnt++; - prz = cxt->przs[*id]; + prz = ramoops_get_next_prz(cxt->przs, &cxt->dump_read_cnt, + cxt->max_dump_cnt, id, type, + PSTORE_TYPE_DMESG, 1); + if (!prz) + return 0; - /* Only supports dmesg output so far. */ - *type = PSTORE_TYPE_DMESG; /* TODO(kees): Bogus time for the moment. */ time->tv_sec = 0; time->tv_nsec = 0; - /* Update old/shadowed buffer. */ - persistent_ram_save_old(prz); size = persistent_ram_old_size(prz); *buf = kmalloc(size, GFP_KERNEL); if (*buf == NULL) -- 2.20.1