| Message ID | 20180422162512.363154748@linutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Thomas, On Sun, 22 Apr 2018 18:23:46 +0200 Thomas Gleixner <tglx@linutronix.de> wrote: > > The rslib usage in dm/verity_fec is broken because init_rs() can nest in > GFP_NOIO mempool allocations as init_rs() is invoked from the mempool alloc > callback. > > Provide a variant which takes gfp_t flags as argument. > > Signed-off-by: Thomas Gleixner <tglx@linutronix.de> > Cc: Mike Snitzer <snitzer@redhat.com> > Cc: Alasdair Kergon <agk@redhat.com> > Cc: Neil Brown <neilb@suse.com> > --- > include/linux/rslib.h | 26 +++++++++++++++++++++++--- > lib/reed_solomon/reed_solomon.c | 36 ++++++++++++++++++++---------------- > 2 files changed, 43 insertions(+), 19 deletions(-) > > --- a/include/linux/rslib.h > +++ b/include/linux/rslib.h > @@ -77,10 +77,30 @@ int decode_rs16(struct rs_control *rs, u > #endif > > /* Create or get a matching rs control structure */ > -struct rs_control *init_rs(int symsize, int gfpoly, int fcr, int prim, > - int nroots); > +struct rs_control *init_rs_gfp(int symsize, int gfpoly, int fcr, int prim, > + int nroots, gfp_t gfp); > + > +/** > + * init_rs - Create a RS control struct and initialize it > + * @symsize: the symbol size (number of bits) > + * @gfpoly: the extended Galois field generator polynomial coefficients, > + * with the 0th coefficient in the low order bit. The polynomial > + * must be primitive; > + * @fcr: the first consecutive root of the rs code generator polynomial > + * in index form > + * @prim: primitive element to generate polynomial roots > + * @nroots: RS code generator polynomial degree (number of roots) > + * > + * Allocations use GFP_KERNEL. > + */ > +static inline struct rs_control *init_rs(int symsize, int gfpoly, int fcr, > + int prim, int nroots) > +{ > + return init_rs_gfp(symsize, gfpoly, fcr, prim, nroots, GFP_KERNEL); > +} > + The version of this patch that Kees has committed to his kspp tree in linux-next has #include <linux/slab.h> why not just #include <linux/types.h> /* for gpf_t */ #include <linux/gpf.h> /* for GFP_KERNEL */ ?
On Tue, Apr 24, 2018 at 6:16 PM, Stephen Rothwell <sfr@canb.auug.org.au> wrote: > Hi Thomas, > > On Sun, 22 Apr 2018 18:23:46 +0200 Thomas Gleixner <tglx@linutronix.de> wrote: >> >> The rslib usage in dm/verity_fec is broken because init_rs() can nest in >> GFP_NOIO mempool allocations as init_rs() is invoked from the mempool alloc >> callback. >> >> Provide a variant which takes gfp_t flags as argument. >> >> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> >> Cc: Mike Snitzer <snitzer@redhat.com> >> Cc: Alasdair Kergon <agk@redhat.com> >> Cc: Neil Brown <neilb@suse.com> >> --- >> include/linux/rslib.h | 26 +++++++++++++++++++++++--- >> lib/reed_solomon/reed_solomon.c | 36 ++++++++++++++++++++---------------- >> 2 files changed, 43 insertions(+), 19 deletions(-) >> >> --- a/include/linux/rslib.h >> +++ b/include/linux/rslib.h >> @@ -77,10 +77,30 @@ int decode_rs16(struct rs_control *rs, u >> #endif >> >> /* Create or get a matching rs control structure */ >> -struct rs_control *init_rs(int symsize, int gfpoly, int fcr, int prim, >> - int nroots); >> +struct rs_control *init_rs_gfp(int symsize, int gfpoly, int fcr, int prim, >> + int nroots, gfp_t gfp); >> + >> +/** >> + * init_rs - Create a RS control struct and initialize it >> + * @symsize: the symbol size (number of bits) >> + * @gfpoly: the extended Galois field generator polynomial coefficients, >> + * with the 0th coefficient in the low order bit. The polynomial >> + * must be primitive; >> + * @fcr: the first consecutive root of the rs code generator polynomial >> + * in index form >> + * @prim: primitive element to generate polynomial roots >> + * @nroots: RS code generator polynomial degree (number of roots) >> + * >> + * Allocations use GFP_KERNEL. >> + */ >> +static inline struct rs_control *init_rs(int symsize, int gfpoly, int fcr, >> + int prim, int nroots) >> +{ >> + return init_rs_gfp(symsize, gfpoly, fcr, prim, nroots, GFP_KERNEL); >> +} >> + > > The version of this patch that Kees has committed to his kspp tree in linux-next has > > #include <linux/slab.h> > > why not just > > #include <linux/types.h> /* for gpf_t */ > #include <linux/gpf.h> /* for GFP_KERNEL */ > > ? We could certainly switch to that. (Why doesn't gfp.h include types.h?) -Kees
On Tue, 24 Apr 2018, Kees Cook wrote: > On Tue, Apr 24, 2018 at 6:16 PM, Stephen Rothwell <sfr@canb.auug.org.au> wrote: > > On Sun, 22 Apr 2018 18:23:46 +0200 Thomas Gleixner <tglx@linutronix.de> wrote: > >> +static inline struct rs_control *init_rs(int symsize, int gfpoly, int fcr, > >> + int prim, int nroots) > >> +{ > >> + return init_rs_gfp(symsize, gfpoly, fcr, prim, nroots, GFP_KERNEL); > >> +} > >> + > > > > The version of this patch that Kees has committed to his kspp tree in linux-next has > > > > #include <linux/slab.h> > > > > why not just > > > > #include <linux/types.h> /* for gpf_t */ > > #include <linux/gpf.h> /* for GFP_KERNEL */ > > > > ? Sure > We could certainly switch to that. (Why doesn't gfp.h include types.h?) Excellent question. Thanks, tglx
--- a/include/linux/rslib.h +++ b/include/linux/rslib.h @@ -77,10 +77,30 @@ int decode_rs16(struct rs_control *rs, u #endif /* Create or get a matching rs control structure */ -struct rs_control *init_rs(int symsize, int gfpoly, int fcr, int prim, - int nroots); +struct rs_control *init_rs_gfp(int symsize, int gfpoly, int fcr, int prim, + int nroots, gfp_t gfp); + +/** + * init_rs - Create a RS control struct and initialize it + * @symsize: the symbol size (number of bits) + * @gfpoly: the extended Galois field generator polynomial coefficients, + * with the 0th coefficient in the low order bit. The polynomial + * must be primitive; + * @fcr: the first consecutive root of the rs code generator polynomial + * in index form + * @prim: primitive element to generate polynomial roots + * @nroots: RS code generator polynomial degree (number of roots) + * + * Allocations use GFP_KERNEL. + */ +static inline struct rs_control *init_rs(int symsize, int gfpoly, int fcr, + int prim, int nroots) +{ + return init_rs_gfp(symsize, gfpoly, fcr, prim, nroots, GFP_KERNEL); +} + struct rs_control *init_rs_non_canonical(int symsize, int (*func)(int), - int fcr, int prim, int nroots); + int fcr, int prim, int nroots); /* Release a rs control structure */ void free_rs(struct rs_control *rs); --- a/lib/reed_solomon/reed_solomon.c +++ b/lib/reed_solomon/reed_solomon.c @@ -59,19 +59,20 @@ static DEFINE_MUTEX(rslistlock); * @fcr: first root of RS code generator polynomial, index form * @prim: primitive element to generate polynomial roots * @nroots: RS code generator polynomial degree (number of roots) + * @gfp: GFP_ flags for allocations * * Allocate a control structure and the polynom arrays for faster * en/decoding. Fill the arrays according to the given parameters. */ static struct rs_control *rs_init(int symsize, int gfpoly, int (*gffunc)(int), - int fcr, int prim, int nroots) + int fcr, int prim, int nroots, gfp_t gfp) { struct rs_control *rs; int i, j, sr, root, iprim; /* Allocate the control structure */ - rs = kmalloc(sizeof (struct rs_control), GFP_KERNEL); - if (rs == NULL) + rs = kmalloc(sizeof(*rs), gfp); + if (!rs) return NULL; INIT_LIST_HEAD(&rs->list); @@ -85,15 +86,15 @@ static struct rs_control *rs_init(int sy rs->gffunc = gffunc; /* Allocate the arrays */ - rs->alpha_to = kmalloc(sizeof(uint16_t) * (rs->nn + 1), GFP_KERNEL); + rs->alpha_to = kmalloc(sizeof(uint16_t) * (rs->nn + 1), gfp); if (rs->alpha_to == NULL) goto errrs; - rs->index_of = kmalloc(sizeof(uint16_t) * (rs->nn + 1), GFP_KERNEL); + rs->index_of = kmalloc(sizeof(uint16_t) * (rs->nn + 1), gfp); if (rs->index_of == NULL) goto erralp; - rs->genpoly = kmalloc(sizeof(uint16_t) * (rs->nroots + 1), GFP_KERNEL); + rs->genpoly = kmalloc(sizeof(uint16_t) * (rs->nroots + 1), gfp); if(rs->genpoly == NULL) goto erridx; @@ -195,13 +196,14 @@ void free_rs(struct rs_control *rs) * in index form * @prim: primitive element to generate polynomial roots * @nroots: RS code generator polynomial degree (number of roots) + * @gfp: GFP_ flags for allocations */ static struct rs_control *init_rs_internal(int symsize, int gfpoly, - int (*gffunc)(int), int fcr, - int prim, int nroots) + int (*gffunc)(int), int fcr, + int prim, int nroots, gfp_t gfp) { - struct list_head *tmp; - struct rs_control *rs; + struct list_head *tmp; + struct rs_control *rs; /* Sanity checks */ if (symsize < 1) @@ -236,7 +238,7 @@ static struct rs_control *init_rs_intern } /* Create a new one */ - rs = rs_init(symsize, gfpoly, gffunc, fcr, prim, nroots); + rs = rs_init(symsize, gfpoly, gffunc, fcr, prim, nroots, gfp); if (rs) { rs->users = 1; list_add(&rs->list, &rslist); @@ -247,7 +249,7 @@ static struct rs_control *init_rs_intern } /** - * init_rs - Find a matching or allocate a new rs control structure + * init_rs_gfp - Find a matching or allocate a new rs control structure * @symsize: the symbol size (number of bits) * @gfpoly: the extended Galois field generator polynomial coefficients, * with the 0th coefficient in the low order bit. The polynomial @@ -256,11 +258,12 @@ static struct rs_control *init_rs_intern * in index form * @prim: primitive element to generate polynomial roots * @nroots: RS code generator polynomial degree (number of roots) + * @gfp: GFP_ flags for allocations */ -struct rs_control *init_rs(int symsize, int gfpoly, int fcr, int prim, - int nroots) +struct rs_control *init_rs_gfp(int symsize, int gfpoly, int fcr, int prim, + int nroots, gfp_t gfp) { - return init_rs_internal(symsize, gfpoly, NULL, fcr, prim, nroots); + return init_rs_internal(symsize, gfpoly, NULL, fcr, prim, nroots, gfp); } /** @@ -279,7 +282,8 @@ struct rs_control *init_rs(int symsize, struct rs_control *init_rs_non_canonical(int symsize, int (*gffunc)(int), int fcr, int prim, int nroots) { - return init_rs_internal(symsize, 0, gffunc, fcr, prim, nroots); + return init_rs_internal(symsize, 0, gffunc, fcr, prim, nroots, + GFP_KERNEL); } #ifdef CONFIG_REED_SOLOMON_ENC8
The rslib usage in dm/verity_fec is broken because init_rs() can nest in GFP_NOIO mempool allocations as init_rs() is invoked from the mempool alloc callback. Provide a variant which takes gfp_t flags as argument. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Mike Snitzer <snitzer@redhat.com> Cc: Alasdair Kergon <agk@redhat.com> Cc: Neil Brown <neilb@suse.com> --- include/linux/rslib.h | 26 +++++++++++++++++++++++--- lib/reed_solomon/reed_solomon.c | 36 ++++++++++++++++++++---------------- 2 files changed, 43 insertions(+), 19 deletions(-)